ACES Publication Search
There are 1584 search results for: Triangular Grids: A Review of Waveguide Analysis with Classical FIT and Some Reflections on Yee-like FIT- and FEM- Schemes
| Title: | Vector Hysteresis Modeling in Arbitrarily Shaped Objects Using an Energy Minimization Approach |
| Abstract: | It is known that proper and efficient modeling of vector hysteresis is crucial to the precise design and performance estimation of electric power devices and magnetic recording processes. Recently, discrete Hopfield neural networks have been successfully utilized in the construction of vector hysteresis models. This paper presents a novel energy-minimization Hopfield neural network approach to implement Stoner-Wohlfarthlike vector hysteresis operators in triangular sub-regions. Advantages of the approach stem from the nonrectangular nature of such operators, which could mimic major hysteresis loops as well as their implementation in the most commonly used triangular discretization subdomains. Details of the approach are given in the paper. |
| Author(s): | A. A. Adly, S. K. Abd-El-Hafiz |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 7 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1305 KB |
| Title: | Tunable Band-Notched UWB Antenna from WLAN to WiMAX with Open Loop Resonators using Lumped Capacitors |
| Abstract: | The proposed antenna in this paper is compact UWB monopole antenna with a rectangular patch consists of stepped cuts and triangular slot. A two open loop resonators are designed and added near microstrip feed line to achieve sufficient band rejection from 5.1 GHz to 6.5 GHz for avoiding interference with WLAN frequency bands. The proposed antenna has low profile and compact size, its size equals 3.2 x 3.2 cm2. It has bandwidth from 3.1 GHz to 19.3 GHz with voltage standing wave ratio (VSWR) < 2, except the undesired band of 5.1–6.5 GHz. Two-lumped capacitors are inserted in order to investigate the ability of tuning the resonance frequency of the band-notched structures from 5.6 GHz to 3.5 GHz. Finally, the layout of the proposed UWB monopole antenna with the notched band is experimentally fabricated and measured to verify the simulation results. Furthermore, the return loss and far-field measurements of the fabricated antenna exhibit good match with simulation predictions. |
| Author(s): | W. A. E. Ali, A. A. Ibrahim |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 6 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2018 KB |
| Title: | Triangular-Arranged Planar Multiple-Antenna for UWB-MIMO Applications |
| Abstract: | A triangular-arranged (TA) planar multiple-antenna is proposed. It consists of three ultra-wideband (UWB) planar monopole antenna elements, with the centers and the ports of the elements arranged at the vertexes of two regular triangles, thus the polarization of each element is 120° different. The performance of the TA multiple-antenna is investigated by simulation and measurement, and the measured results agree with the simulated ones in reasonable precision. Within the ultra-wide bandwidth of 3.4 GHz – 12 GHz, the return loss at each port is better than 10 dB, and the isolation between any two ports is higher than 20 dB. Furthermore, good omni-directional radiation pattern is obtained over the interesting frequency band. A linear-arranged (LA) threeelement multiple-antenna is compared with the proposed TA antenna. Comparison between the TA antenna and the LA antenna validates the advantages of the proposed one, which consequently is suitable for UWB-MIMO applications. |
| Author(s): | X.-S. Yang, S.-G. Qiu, J.-L. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 1 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 2389 KB |
| Title: | Triangular Ring Patch Antenna Analysis: Neuro-Fuzzy Model for Estimating of the Operating Frequency |
| Abstract: | In this study, a neuro-fuzzy (NF) analysis method is suggested for the estimation of the operating frequency of triangular ring patch antennas (TRPAs) that operate at ultra high band applications. Although the analysis of regular-shaped patch antennas (PAs) such as rectangular, triangle, and circle is easy, analysis of irregularly shaped patch antennas is difficult and time consuming. Here, this great effort and time has been eliminated by using an artificial intelligence technique such as NF. To create a data set for NF, 100 TRPAs with different physical and electrical properties (L, l, h, and er) are simulated by using an electromagnetic simulator program. The currency and accuracy of the proposed approach is then confirmed on the measurement results of a prototype TRPA fabricated in this study. The results of NF model are compared with the simulation/ measurement results and previously the method published in the literature. |
| Author(s): | A. Kayabasi |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 11 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 4601 KB |
| Title: | Triangular Patch Yagi Antenna with Reconfigurable Pattern Characteristics |
| Abstract: | A pattern reconfigurable Yagi patch antenna is proposed. The antenna is composed of three triangular microstrip patches, i.e., one driven patch and two parasitic patches. By controlling switches, which are installed on the parasitic patches, the radiation pattern of the antenna can point to three different directions, covering an elevation range from -61° to +63° in the E-plane. The simulated and measured results are presented and they agree with each other in reasonable precision. |
| Author(s): | J. Zhang, X. S. Yang, J. L. Li, B. Z. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 11 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 899 KB |
| Title: | Triangular Grids: A Review of Waveguide Analysis with Classical FIT and Some Reflections on Yee-like FIT- and FEM-Schemes |
| File Type: | Conference Paper |
| Issue: | Volume: Time Domain Numerical Modeling Beyond FDTD Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 738 KB |
| Title: | Triangular Grids: A Review of Resonator and Waveguide Analysis with Classical FIT and Some Reflections on Yee-like FIT- and FEM-Schemes |
| Abstract: | Abstract—The focus of this paper is on the solution of Maxwell's equations on triangular orthogonal grids for timeharmonic elds in cylindrically symmetric resonators and general time dependant elds in length-homogeneous waveguides, respectively. The method is based on the Finite Integration Technique (FIT) [1], [2]. The 2D simulation on a structured triangular grid combines the advantages of FIT, as e.g. the consistency of the method or the numerical advantage of banded system matrices, with the geometrical exibility of noncoordinate grids. FIT on triangular grids was rst introduced in [3], [4]1. This paper presents a review describing the underlying theory in FIT operator notation rst introduced in [2] and puts this classical approach for FIT on triangular grids in relation to actual research in the eld. |
| Author(s): | URSULA VAN RIENEN, URSULA VAN RIENEN |
| File Type: | Journal Paper |
| Issue: | Volume: 19 Number: 1 Year: 2004 |
| Download Link: | Click here to download PDF File Size: 973 KB |
| Title: | Transmission through an Arbitrarily Shaped Aperture in a Conducting Plane Separating Air and a Chiral Medium |
| Abstract: | The analysis of chiral materials has been an important subject in computational electromagnetics. In this paper, the method of moments technique is used to solve the problem of transmission through an arbitrarily shaped aperture separating air and a chiral medium. The aperture is in an infinite PEC (perfect electric conductor) plane. The excitation is assumed to be a plane wave in air. The equivalence principle is used to replace the aperture with a conducting surface with an equivalent magnetic current on each side of it. By enforcing the continuity of the tangential components of the total electric and magnetic fields across the aperture, coupled integral equations are obtained. The aperture has been modeled by triangular patches. The equivalent magnetic currents are approximated by linear combinations of expansion functions. The mixed potential formulation for a homogeneous chiral medium is used to obtain the electric and the magnetic fields produced by these expansion functions. The coefficients of these expansion functions are obtained by using the method of moments to solve the coupled integral equations. |
| Author(s): | S. T. Imeci, F. Altunkilic, J. R. Mautz, E. Arvas |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 7 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 747 KB |
| Title: | Transient Electromagnetic Scattering from Dielectric Objects Using Time-Domain Integral Equation |
| File Type: | Conference Paper |
| Issue: | Volume: Computational Techniques Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 197 KB |
| Title: | Transient Analysis of Electromagnetic Scattering using Marching-on-in-Order Time-Domain Integral Equation Method with Curvilinear RWG Basis Functions |
| Abstract: | In this paper, a modified marching-onin- order time-domain integral equation method is utilized to analyze transient electromagnetic scattering from arbitrarily shaped objects. The spatial and temporal testing procedures are separate, and both of them are performed with the Galerkin’s method. The curvilinear RWG basis functions are used as spatial basis functions with curved triangular patch modeling. It gives a remarkable reduction to the number of unknowns, also the memory requirement and CPU time, without sacrificing the accuracy. The use of the weighted Laguerre polynomials as temporal basis functions ensures an absolutely stable solution even in late time. Several numerical results, including the single ogive and NASA almond, are given to demonstrate the accuracy and efficiency of the proposed method. |
| Author(s): | Q. Q. Wang, C. Yan, Y. F. Shi, D. Z. Wang, R. S. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 5 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 989 KB |
| Title: | THE LINEAR-PHASE TRIANGULAR FACET APPROXIMATION IN PHYSICAL OPTICS ANALYSIS OF REFLECTOR ANTENNAS |
| Abstract: | Numerical analysis of reflector antennas uses a discrete approximation of the radiation integral. The calculation replaces the actual reflector surface with a triangular facet representation. The physical optics current is then approximated within each facet. This paper provides analytical details of the method based on the assumption of a constant magnitude and linear-phase approximation of the physical optics current. Example calculations are provided for parabolic, elliptical, and shaped subreflectors. The computed results are compared with calculations made using a constant-phase approximation. These results show that the linear-phase approximation is a significant improvement over the constant-phase approximation in that the solution converges over a larger angular region of space. This improvement can significantly reduce storage requirements and possibly execution speed. [Vol. 6, No. 2, pp. 74-85 (1991)] |
| Author(s): | W. A. Imbriale, R. E. Hodges, W. A. Imbriale, R. E. Hodges |
| File Type: | Journal Paper |
| Issue: | Volume: 6 Number: 2 Year: 1991 |
| Download Link: | Click here to download PDF File Size: 409 KB |
| Title: | The Combination of GPU and CPU Techniques to Fast Calculate High Frequency Scattered Fields from 3-D Realistic Scatterers |
| File Type: | Conference Paper |
| Issue: | Volume: 10-TE-3 Recent Advances on Electromagnetics Modeling and Simulation Techniques II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 609 KB |
| Title: | The analysis of transient scattering for rectangular incident waves using the discrete Laguerre transforms |
| File Type: | Conference Paper |
| Issue: | Volume: Higher Order Methods Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 188 KB |
| Title: | SURFACE MODELLING FOR EM INTERACTION ANALYSIS |
| Abstract: | This paper deals with the numerical modelling of the surface of a structure with a wire grid or a surface patch for Electromagnetic (EM) interaction analysis. Surface currents and fields on a wire grid model are computed using the Numerical Electromagnetics Code (NEC). The results are compared with those obtained on a triangular surface patch model using an Electric Field Integral Equation (EFIE) formulation. Simple structures such as a square plate as well as complicated structures such as an aircraft are considered. Good agreement is obtained in most cases. [Vol. 6, No. 2, pp. 38-52 (l99l)] |
| Author(s): | S. Kashyap, A. Loule, S. Kashyap, A. Loule |
| File Type: | Journal Paper |
| Issue: | Volume: 6 Number: 2 Year: 1991 |
| Download Link: | Click here to download PDF File Size: 587 KB |
| Title: | Subdividing Distorted Prisms into Tetrahedra |
| File Type: | Conference Paper |
| Issue: | Volume: Finite Element Method and Applications Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 133 KB |
| Title: | Square Shape Patch Antenna with Triangular Slot |
| File Type: | Conference Paper |
| Issue: | Volume: S10 EM Simulations using Sonnet I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 722 KB |
| Title: | Spherical Aperture-Coupled Antennas with Parasitic Element |
| Abstract: | Theory and experiment of spherical aperture-coupled antennas with parasitic elements are presented in this paper. Current distributions on slot and conformal patches are calculated using spatial domain electric and magnetic Dyadic Green's Functions (DGFs). Electromagnetic fields for such a structure have been calculated with the aid of linear Rao-Wilton-Glisson (RWG) triangular basis functions and by converting spherical DGFs to Cartesian DGFs. In order to validate the proposed method, a prototype of this antenna is fabricated and tested. The effect of parasitic element on antenna characteristics such as gain and radiation pattern is investigated. Good agreement between the results shows accuracy and high convergence speed of the presented method. |
| Author(s): | J. S. Meiguni, M. Kamyab, A. Hosseinbeig |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 12 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 476 KB |
| Title: | Slotted Triangular Monopole Antenna for UHF RFID Readers |
| Abstract: | A new compact slotted triangular monopole antenna for ultra-high frequency (UHF) radio frequency identification (RFID) applications is presented. The antenna exhibits an omnidirectional radiation pattern and has a bandwidth (BW) of more than 13%. It covers the global UHF RFID band and has a maximum gain of around 2.6 dBi. An overview of the antenna design along with the full wave simulation is provided. A prototype of the antenna is fabricated and tested. Good agreement is obtained between simulated and measured results. Moreover, the antenna is used with a UHF RFID reader in real use cases where read range and read rate with different commercial tags are used to evaluate the antenna performance. |
| Author(s): | K. ElMahgoub |
| File Type: | Express Journal Paper |
| Issue: | Volume: 1 Number: 1 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 367 KB |
| Title: | Slotted Triangular Monopole Antenna for UHF RFID Readers |
| Abstract: | A new compact slotted triangular monopole antenna for ultra-high frequency (UHF) radio frequency identification (RFID) applications is presented. The antenna exhibits an omnidirectional radiation pattern and has a bandwidth (BW) of more than 13%. It covers the global UHF RFID band and has a maximum gain of around 2.6 dBi. An overview of the antenna design along with the full wave simulation is provided. A prototype of the antenna is fabricated and tested. Good agreement is obtained between simulated and measured results. Moreover, the antenna is used with a UHF RFID reader in real use cases where read range and read rate with different commercial tags are used to evaluate the antenna performance. |
| Author(s): | K. ElMahgoub |
| File Type: | Express Journal Paper |
| Issue: | Volume: 32 Number: 12 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1842 KB |
| Title: | Slotted Triangular Monopole Antenna for UHF RFID Readers |
| Abstract: | A new compact slotted triangular monopole antenna for ultra-high frequency (UHF) radio frequency identification (RFID) applications is presented. The antenna exhibits an omnidirectional radiation pattern and has a bandwidth (BW) of more than 13%. It covers the global UHF RFID band and has a maximum gain of around 2.6 dBi. An overview of the antenna design along with the full wave simulation is provided. A prototype of the antenna is fabricated and tested. Good agreement is obtained between simulated and measured results. Moreover, the antenna is used with a UHF RFID reader in real use cases where read range and read rate with different commercial tags are used to evaluate the antenna performance. |
| Author(s): | K. ElMahgoubb |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 12 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1842 KB |
| Title: | Size-Reduced Equilateral Triangular Metamaterial Patch Antenna Designed for Mobile Communications |
| Abstract: | A size-reduced equilateral triangular metamaterial patch antenna (ETMPA) is proposed for the 5G mobile communications. The new ETMPA is formed from a conventional equilateral triangular patch antenna (ETPA) by additionally loading triangular-shaped mushroom metamaterials. One ETMPA is experimentally demonstrated. It is shown to resonate at 3.488GHz. The side length is only 0.483λg, which is much smaller than that for a conventional ETPA with a length of 0.66λg. Despite its compactness, the ETMPA has an acceptable bandwidth of 2.1% and antenna gain of 6.3dBi in measurement. These performances make the compact ETMPA proposing to be used in the wireless communications at 3.5GHz. |
| Author(s): | G. Dai, X. Xu, X. Deng |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 8 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 2135 KB |
| Title: | SIMPLIFIED ANALYTICAL SOLUTIONS FOR MAGNETIC SIMULATION OF NEURONS |
| Abstract: | Strong pulses of magnetic field are used to stimulate peripheral nerves and motor neurons in the cerebral cortex,. Such stimulation is used in neurology for numerous diagnostic purposes. The electric field induced in tissue along the neuron and its spatial derivative are the parameters determining neural response. Another important parameter influencing the efficiency of stimulation is the inductance of a coil producing the magnetic field, as it defines the current time derivative for a given pulse generator. For arbitrarily located coils of arbitrary shapes, a semi-analytical solution is presented to calculate spatial distributions of the electric field and its spatial derivatives in a semi-infinite tissue model. Analytical solutions are given for coils composed of linear segments parallel or perpendicular to the air- tissue interface. Expressions for inductance of coils having suitable geometries for neural stimulation are derived. Coils can be optimized for stimulation of nerves at given orientation and distance from the air-tissue interface. In the optimization, coil dimensions and shape are considered as they affect both the induced field and inductance. A quadruple coil consisting of triangular sections appears to offer some advantages over other shapes for stimulation of shallow nerves. For deep nerves spaces quadruple square and three-dimensional coils are preferred. Analyses described are useful in evaluating various options, gaining an insight into the physical phenomena involved, and as the first step before undertaking a numerical analysis of models more closely representing the tissue electrical and geometrical complexities. [Vol. 7, No. 2, pp. 162-178 (1992), Special Issue on Bioelectromagnetic Computations] |
| Author(s): | Karu P. Esselle, Maria A. Stuchly, Karu P. Esselle, Maria A. Stuchly |
| File Type: | Journal Paper |
| Issue: | Volume: 7 Number: 2 Year: 1992 |
| Download Link: | Click here to download PDF File Size: 914 KB |
| Title: | Simple and Efficient Design of Reconfigurable FSS with Triangular Patch Elements |
| File Type: | Conference Paper |
| Issue: | Volume: S13 Advances in EM Modeling and Optimization From Theory to Applications II Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 307 KB |
| Title: | Resolution of 2D Time Domain Electric Field Integral Equation: Novel formulation of RWG associated to Laguerre Polynomials |
| File Type: | Conference Paper |
| Issue: | Volume: S20 Integration Equation Techniques & Applications Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 267 KB |
| Title: | Receiver Sites for Accurate Indoor Position Location Systems |
| File Type: | Conference Paper |
| Issue: | Volume: Technologies for Ultra-Wideband Communication Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 230 KB |
| Title: | RCS Estimation of 3D Metallic Targets Using the Moment Method and Rao-Wilton-Glisson Basis Functions |
| Abstract: | This work deals on the estimation of the radar cross section (RCS) of five three-dimensional conductive objects: the metallic sphere, NASA almond, single ogive, double ogive and conesphere, using the Moment Method. The Rao-Wilton-Glisson (RWG) basis functions were used to expand the surface current of targets inside the Electric Field Integral Equation (EFIE). Triangular domains of RWG basis functions were constructed using MATLAB tessellation capabilities and a MATLAB code was developed and run to solve the electromagnetic scattering problem. As a result five RCS graphs, one for each target, were obtained. The accuracy of the program was validated by comparing the obtained results with those reported in the Literature. |
| Author(s): | G. K. Carvajal, D. J. Duque, A. J. Zozaya |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 5 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 474 KB |
| Title: | Preconditioning Effect of Multiple-Scattering-Based Macro Basis Function Approach |
| File Type: | Conference Paper |
| Issue: | Volume: Advanced Integral Equation Methods Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 324 KB |
| Title: | Performance analysis of MoM patch antenna simulations - RWG basis functions |
| File Type: | Conference Paper |
| Issue: | Volume: Advanced Computational Techniques for System Design Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 1009 KB |
| Title: | Patch Antenna with Triangular Slitted Corners |
| Abstract: | In this paper, a microstrip patch antenna with triangular slits was designed, simulated, fabricated and tested. The proposed patch antenna, with operating frequency of 9.5 GHz, is targeted. Simulation is carried out using Sonnet Suites. Antenna has 9.68 dB gain at 9.5 GHz with corresponding reflection coefficient of -19 dB. Proposed antenna introduces size reduction for patch antennas. The measurements of the fabricated patch antenna well corroborate the simulation results. |
| Author(s): | A. Elakas, G. A. Irmak, M. Sencan, S. T. Imeci, T. Durak |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 2 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1586 KB |
| Title: | New Basis Functions for the Electromagnetic Solution of Arbitrarily-shaped, Three Dimensional Conducting Bodies Using Method of Moments |
| File Type: | Conference Paper |
| Issue: | Volume: MoM and Applications Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 221 KB |
| Title: | New Antennas Based on Triangular Patch as a Solution for RFID Application |
| Abstract: | This paper covers the design of a new antenna for RFID applications at microwave frequencies. Five antennas are studied. The first three structures are inspired from a triangular patch, whereas the fourth and the fifth are inspired from a Sierpenski fractal antenna. The size reduction is more than 80%, which explains the utility of the proposed antennas. |
| Author(s): | A. Ferchichi, N. Sboui, A. Gharsallah, H. Baudrand |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 3 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 477 KB |
| Title: | Multiband Multipolarized Planar Antenna for WLAN/WiMAX Applications |
| File Type: | Conference Paper |
| Issue: | Volume: S19 Finite-Difference Time-Domain Method: Theory and Applications Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 232 KB |
| Title: | Modeling of Surface Roughness Effects on the Performance of Rectangular u-Coaxial Lines |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Finite Element Technique and its Applications Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 466 KB |
| Title: | Modeling Corner Singularities in Triangular Cells with Hierarchical Bases |
| File Type: | Conference Paper |
| Issue: | Volume: Higher Order CEM: Development and Applications Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 475 KB |
| Title: | Miniaturized Microstrip Lowpass Filter with Ultra-Wide Stopband |
| Abstract: | A new microstrip lowpass filter with compact size and ultra-wide stopband is presented. Using triangular patch resonators and butterfly resonator with four 45° radial “wing” patches, the introduced filter can successfully realize compact design and ultra-wide stopband. To further reduce the circuit size of the filter, the meander transmission lines are also adopted in the design. A demonstration filter with 3 dB cutoff frequency at 1.6 GHz has been designed, fabricated, and measured. Measured results show that the lowpass filter has an ultra-wide stopband bandwidth of 153.9 %, which is able to suppress the 11th harmonic response. Furthermore, it also has a small size of 14 ? 15 mm2, which corresponds to 0.114 ?g ? 0.122 ?g, where ?g is the guided wavelength at 1.6 GHz. |
| Author(s): | Y. Dou, J. Wang, H. Cui, J. L. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 805 KB |
| Title: | Microstrip Patch Antenna with Triangular Slits |
| File Type: | Conference Paper |
| Issue: | Volume: S57 Design Simulation and Build Microwave Devices using Sonnet Suites Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 420 KB |
| Title: | Low-Profile Broadband Top-Loaded Triangular Antenna with Folded Rim |
| Abstract: | This paper presents the impedance matching technique and the bandwidth characteristics of a low-profile top-loaded triangular antenna with oblique shorting pins. The folded rim is arranged at the edge of the finite ground plane. The bandwidth diagrams for various antenna heights, finite sizes of the ground plane, and the widths of the folded rim are obtained through the moment-method simulation. The maximum bandwidth of 43 % is achieved with 0.05 ? height. For the low-profile configuration, the bandwidth of 17 % is obtained with 0.03 ? height. |
| Author(s): | N. Michishita, W. J. Kim, Y. Yamada |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 2 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 991 KB |
| Title: | Isosceles Right Triangular Waveguides |
| File Type: | Conference Paper |
| Issue: | Volume: 2-4-B Novel Antenna Design and Analysis Method for Remote Sensing and Other Related Applications Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 341 KB |
| Title: | Improper Integrals Calculations for Fourier Boundary Element Method |
| Abstract: | This paper presents a method of regularization for the numerical calculation of improper integrals used in different formulations of Boundary Element Method (BEM). The main attention of the readers we would like to focus on Fourier Formulation of BEM. The singular integrals arise when for discretization the elements of a higher order than zero are used. Very often in the Diffusive Optical Tomography for infant head modeling, triangular or square curvilinear boundary elements of the second order are used [12,14], hence, our interest in the subject of effective and accurate calculation of singular integrals. Even for the classical formulation of BEM such a problem is extremely difficult [1]. Some authors believe that the practical application possesses only flat triangular boundary elements of zero-order, and although there is some truth in this statement, the elements of the second order show a significant advantage [10,12] in Diffusion Optical Tomography (DOT) for example. This issue becomes even more interesting when we deal with the Galerkin BEM formulation offering the possibility of matrix of coefficients symmetrisation, which has fundamental importance for inverse problems. This matter becomes critical when we start to consider the Fourier BEM formulation, introduced by Duddeck [5]. His approach provides the possibility of a solution in the case which has no fundamental solution. The light propagation, which is described by the Boltzmann equation (see Arridge [2]) is such a case. Currently and most commonly, the Boltzmann equation is approximated by the diffusion equation in strongly light scattering media [10]. In the author’s opinion, the problem of numerical integration of improper integrals has not yet been fully exhausted in the classic and Galerkin BEM formulation but the Fourier BEM formulation still expects the proposals of the effective solutions. Such an offer we would like to present in this paper. |
| Author(s): | J. Sikora, K. Polakowski, B. Panczyk |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 9 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 2000 KB |
| Title: | High-order Chebyshev-based Nystrom Methods for Electromagnetics |
| File Type: | Conference Paper |
| Issue: | Volume: S05 Locally Corrected Nystrom Method and its Applications Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 3313 KB |
| Title: | High Frequency Radiation Pattern Analysis for Antennas Mounted on Material-Coated Conducting Platforms of General Shape |
| File Type: | Conference Paper |
| Issue: | Volume: Higher Order Methods Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 159 KB |
| Title: | Hierarchical Vector Basis Functions for Meshes with Hexahedra, Tetrahedra, and Triangular Prism Cells |
| File Type: | Conference Paper |
| Issue: | Volume: 30 Years of RWG Basis Functions Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 96 KB |
| Title: | Hierarchical Divergence-Conforming Basis Functions for Meshes with Hexahedra, Tetrahedra, and Triangular Prism Cells |
| File Type: | Conference Paper |
| Issue: | Volume: Advanced Integral Equation Methods Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 176 KB |
| Title: | Genetic-Algorithm Optimization of an Array for Near-Field Plane Wave Generation |
| Abstract: | An alternative approach to the design of an array antenna to be used to generate plane waves in the near field is presented. The original array was designed on the basis of a triangular grid of seven elements arranged in a hexagon, to minimize the number needed to achieve approximately uniform illumination of the test zone, under the assumption of isotropic element radiation patterns. In the alternative approach, a genetic algorithm was used to discover more economical distributions of elements which could still generate acceptable approximations to a plane wave zone. It was found that considerable simplifications from the 'common sense' approach were possible. |
| Author(s): | Neil N. Jackson, Peter S. Excell, Neil N. Jackson, Peter S. Excell |
| File Type: | Journal Paper |
| Issue: | Volume: 15 Number: 2 Year: 2000 |
| Download Link: | Click here to download PDF File Size: 9694 KB |
| Title: | Gain-Enhanced Wideband Circularly Polarized Antenna with a Non-Uniform Metamaterial Reflector |
| Abstract: | In this paper, a gain-enhanced wideband circularly polarized (CP) antenna with a non-uniform metamaterial (NUM) reflector is presented, which is composed of a modified wide S-shaped slot antenna and a NUM reflector. To achieve a wideband CP operation, a modified S-shaped slot is fed by an L-shaped microstrip feedline that ends with a triangular patch to improve axial ratio (AR) bandwidth and impedance bandwidth. A NUM reflector composed of rectangular metal units with different sizes is employed and its units are unevenly distributed. The proposed CP antenna is designed, fabricated, and measured. The measured results show that the impedance bandwidth covers 3.0-6.0 GHz (66.7%) and a 3-dB AR bandwidth covers 3.1-5.6 GHz (57.4%). A peak gain of 6.0 dBi is obtained at 3.8 GHz by using the reflector. The advantages of the proposed antenna are the simple structure, high gain, and broad CP bandwidth. |
| Author(s): | B. Qiu, Y. Xia, Y. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 3 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 1400 KB |
| Title: | Fast EM Scattering Analysis for the Hard Targets in a Layered Medium by Using the Hierarchical Vector Basis Functions |
| Abstract: | This paper presents an efficient algorithm combining a higher order method of moments (MoM) with the adaptive cross approximation-singular value decomposition (ACA-SVD) algorithm for the threedimensional perfect electric conductor (PEC) targets located in a planar layered medium. An efficient set of hierarchical divergence-conforming vector basis functions based on curved triangular mesh is used to expand the induced surface electric current density on the metal surface of the target in layer medium. A three level discrete complex images methods (DCIM) is applied to efficiently obtain the closed form spatial Green’s functions. To be able to solve the electrically large problems, the ACA-SVD algorithm is proposed to accelerate the matrix-vector multiplication and reduce the memory requirements when the corresponding matrix equation is solved by a Krylov-subspace iterative method. The electromagnetic scattering from the practical model of hard targets buried in a lossy medium is analyzed in this paper, and numerical examples demonstrate the accuracy and efficiency of the proposed technique for the electrically large scattering problems in layered medium. |
| Author(s): | L. Zha, R. Chen, T. Su |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 11 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 595 KB |
| Title: | Evaluation of the Contour Integral on Curved Edges in Time Domain Equivalent Edge Currents |
| File Type: | Conference Paper |
| Issue: | Volume: S03 Advances in Curved Patch Modeling Number: Year: 2019 |
| Download Link: | Login To Download (For Members) File Size: 618 KB |
| Title: | EM Analysis of PEC Object above Halfspace by Using Higher-Order Hierarchical Vector Basis Functions |
| File Type: | Conference Paper |
| Issue: | Volume: 4-P4-A Electromagnetic Thoery and Computational Methods Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 550 KB |
| Title: | Electromagnetic Transmission Through an Aperture in a Conducting Plane Between Air and a Chiral Medium |
| File Type: | Conference Paper |
| Issue: | Volume: Guided Waves in Non-Standard Media Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 85 KB |
| Title: | ELECTROMAGNETIC SCATTERING BY AN ARBITRARILY SHAPED SURFACE WITH AN ANISOTROPIC IMPEDANCE BOUNDARY CONDITION |
| Abstract: | The problem of electromagnetic scattering from arbitrarily shaped, imperfectly conducting surfaces that can be represented by an anisotropic impedance boundary condition is solved numerically using the electric field integral equation and a triangular patch model for the surface. The anisotropic impedance boundary condition function is described by a constant surface dyadic within each triangular face. The procedure is validated by comparison of numerical results obtained with the triangular patch model with body of revolution model results for problems involving scattering by spheres and cylinders having uniform or anisotropic impedance boundary conditions. [Vol. 10, No. 3 (1995), Special Issue on Advances in the Application of Method of Moments to Electromagnetic Radiation and Scattering Problems, pp 93-106] |
| Author(s): | Allen W. Glisson, Mark Orman, Frank Falco, Donald Koppel, Allen W. Glisson, Mark Orman, Frank Falco, Donald Koppel |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 3 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 1128 KB |
| Title: | Electromagnetic Coupling Analysis of Transient Excitations of Rectangular Cavity through Slot using TD-EFIE with Laguerre Polynomials as Temporal Basis Functions |
| Abstract: | This paper presents an electromagnetic coupling analysis of transient waves excited a rectangular cavity containing an interior scatterer coupled to an external scatterer through a slot. Based on the equivalence principle, time domain integral equations are established by enforcing the boundary conditions on the internal and external scatterers, the slot and the cavity walls. The method of moments is applied in space and time domains to solve the developed system of integral equations. The unknown coefficients of the electric and magnetic currents are approximated by the triangular piecewise functions associated with Dirac function as space basis. To obtain accurate and stable solutions, the Laguerre functions are used as temporal basis. Numerical results involving the coupling effects between the cavity components are investigated. The numerical results are found to be in good agreement with EM theory and literature. |
| Author(s): | D. Omri, T. Aguili |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1645 KB |
| Title: | Electric Field Distribution in a Biological Cell for Various Electrode Configurations-A Simulation Study |
| Abstract: | Electroporation or electropermeabilization (EP) is a non-viral physical process of inducing and/or increasing permeability of biological membranes by the application of high intensity and short duration electrical pulses. The resulting high field strength in the membrane can lead to the formation of regions of increased permeability, often called pores that allow transmembrane transport of macromolecules, such as DNA and chemo drugs. The efficacy of EP depends on a number of parameters, such as electric field strength, duration, number of pulses, size of target cell, and type of drug or DNA to be fed, to mention a few parameters. While electric field strength, duration, and number of pulses are the dominant parameters for the electroporation effect, the electric field distribution also depends on the shape, the size, and the material of electrodes used. The various electrodes used in practice are the parallel plate electrodes, the needle electrodes, the needle array electrodes, and the caliper electrodes. Both six needle array and parallel plate electrodes were used in the skin cancer trials. The electric field distribution varies with the type of electrode. The choice of electrodes depends upon the type of application. For example, parallel plate electrodes produce good results in human clinical trials and the distance between the electrodes can be easily varied. Needle electrodes are the simplest, but due to their configuration, the field distribution is highly nonlinear; there is higher field strength around the needle tip. That is one of the reasons for using multiple needles or needle arrays to make the field distribution as uniform as possible. It is of practical interest to study the electric field distribution of various electrodes to make a more informed choice of which electrodes to use. This paper presents the results of a study of the electric field distribution in biological tissues for various electrode configurations. Magwel was used in this study. For the same voltage applied, the triangular and arc electrode configuration developed the highest electric field strength. Specifically, we develop simulation results that enhance or enable the acquisition of information from cells. |
| Author(s): | M. O. Goni |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 5 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 910 KB |
| Title: | Efficient Time Integration Strategies for High Order Discontinuous Galerkin Time Domain Methods |
| File Type: | Conference Paper |
| Issue: | Volume: Finite-Volume and Discontinuous Galerkin Time-Domain Techniques Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 2163 KB |
| Title: | Efficient Evaluation of the Logarithmic Singularity on Elongated Triangles With a 16 Nodes Polynomial Quadrature |
| File Type: | Conference Paper |
| Issue: | Volume: Recent Advances in Integral Equations and Fast Methods Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 2160 KB |
| Title: | Dual-band (28/38 GHz) Yagi–Uda Antenna with Corrugated Radiator and Triangular Reflectors for 5G Mobile Phones |
| Abstract: | A novel printed design of a Yagi–Uda antenna is introduced for dual-band operation at 28/38 GHz. A corrugated strip dipole with a capacitively end-coupled extension strip is employed as the driven element. The proposed antenna has two triangular-shaped reflectors and one director. The driven dipole is fed through a coaxial feed line constructed as three unequal length transition strips. A four-port MIMO antenna system constructed using the proposed Yagi–Uda is suggested for mobile phones. CSTr simulator is used to study the effect of the different design parameters on the antenna gain and the operating bands. Numerical and experimental investigations are achieved to assess the performance of both the single-element antenna and the four-port MIMO antenna system. It is shown that the simulation results agree with the experimental measurements and both show good performance of the single antenna as well as the MIMO antenna system. The bandwidths achieved around 28 GHz and 38 GHz are about 4 GHz and 1.4 GHz, respectively. The gain of the antenna is about 9 and 10 dB at 28 and 38 GHz, respectively. The four-antenna configuration shows radiation pattern diversity required for MIMO system. The envelope correlation coefficient (ECC) and the diversity gain (DG) are calculated and the results show that the proposed MIMO antenna system is suitable for the forthcoming 5G mobile communications. |
| Author(s): | A. E. Farahat, K. F. A. Hussein |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 10 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 14915 KB |
| Title: | Design of a Planar UWB Antenna with New Band Enhancement Technique |
| Abstract: | A planar antenna and a technique for enhancing its bandwidth for UWB applications have been proposed in this paper. The proposed antenna which has a compact structure and the total size of 30 × 22 mm2 consists of a square patch and a partial ground plane. Numerical study shows that the bandwidth of the proposed antenna can be controlled mainly by the patch size and width of the feeding line. The cutting triangular shape slots on the top edge of the ground plane help to increase the bandwidth by 43.6% (3.89 GHz). The measured -10 dB return loss bandwidth of the proposed antenna ranges from 2.95 GHz to 15.45 GHz which covers the entire UWB band. The nearly stable radiation pattern with a maximum gain of 5.9 dBi makes the proposed antenna suitable for being used in UWB communication. |
| Author(s): | R. Azim, M. T. Islam, N. Misran |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 10 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 386 KB |
| Title: | Design and Analysis of EBG Antenna for Wi-Fi, LTE, and WLAN Applications |
| Abstract: | A non-planar electromagnetic band gap (EBG) structured antenna is proposed in this paper for wireless communication applications. The proposed design consists of coplanar waveguide (CPW) fed square patch antenna embedded with triangular EBG backing on FR-4 substrate material for 2.4 GHz (Wi-Fi, LTE) and 5.2 GHz (WLAN) applications. Gain is improved from 2.8 dB to 13.9 dB by adding EBG structure in the proposed antenna and the parametric analysis is done for optimizing the antenna performance characteristics. The proposed antenna provides a maximum efficiency of 82.5% in the resonating frequencies. The prototyped antenna is having good correlation with the simulation results obtained from Finite Element Method (FEM) based Anyss-HFSS. High Frequency Structure Simulator is used to analyze the antenna parameters and the simulated and measured results are correlating well with each other with a slight change in frequencies. |
| Author(s): | P. Bora, P. Pardhasaradhi, B. T. P. Madhav |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 9 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 2284 KB |
| Title: | Compact W-Band Antipodal Fin-Line Transition from SIW to Rectangular Waveguide |
| File Type: | Conference Paper |
| Issue: | Volume: 4-1-C Passive/Active Microwave and Terahertz Devices Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 295 KB |
| Title: | Coalescing Tetrahedral TLM cells into Higher Order Elements for Improved Efficiency |
| File Type: | Conference Paper |
| Issue: | Volume: Recent Developments and Applications with Time-domain Modeling Techniques Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 63 KB |
| Title: | Blind Separation of Human Motions Based on Independent Component Analysis |
| File Type: | Conference Paper |
| Issue: | Volume: 1-P1-A Student Paper Contest Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 625 KB |
| Title: | Beyond RWG/Galerkin Solutions of the EFIE: Investigations into Pointmatched, Discontinuous, and Higher Order Discretizations |
| File Type: | Conference Paper |
| Issue: | Volume: 30 Years of RWG Basis Functions Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 365 KB |
| Title: | Barycentric Quadrilateral Basis on Triangular and Quadrilateral Meshes for Stable Surface Integral Equations |
| File Type: | Conference Paper |
| Issue: | Volume: Fast Integral Equation Methods and Stable Discretization Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 509 KB |
| Title: | Babinet’s Principle Applied to Distributed Arrays |
| File Type: | Conference Paper |
| Issue: | Volume: S15 Antenna Arrays and Applications Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 497 KB |
| Title: | Array Pattern Reconfiguration Using Pixel Method |
| Abstract: | In this paper, the array elements are considered as pixels and their magnitude excitations are assigned to the values of 1 (i.e., active or turned ON) or 0 (i.e., inactive or turned OFF). Thus, each element either exists at its position in the considered array or not. The proposed pixel method can be applied to different planar array configurations such as square, rectangular, triangular, circular, or any other shape to achieve the required pattern reconfigurability. Moreover, by turning OFF some of the selected elements, the main beam of the array pattern can be switched to specify directions without using any phase shifters or any other RF components. Therefore, its practical implementation is simpler and cheaper than any other existing method. However, when comparing with arrays in which all their elements are turned ON, the gain of the considered arrays will be reduced when some selected elements are turned OFF. The array pattern reconfiguration using the pixel method has been designed and its parameters have been optimized using computer simulation Technology (CSTMWS), which uses the Finite Integration Technique (FIT). It’s also verified by High-Frequency Surface Structure (HFSS) commercial software (based on the FEM method). Numerical results obtained under fullwave modeling CST environment demonstrate the effectiveness of the described method. |
| Author(s): | K. M. Younus, J. R. Mohammed |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 3 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1743 KB |
| Title: | Arbitrary Shaped Homogeneous Invisible Ground Cloak |
| Abstract: | A general approach is introduced to design an arbitrary shaped invisible ground cloak with homogeneous constitutive parameters. The proposed homogenous ground cloak design method facilitates the fabrication process and achieves a variety of choices for choosing the cloak shape. In this approach, an arbitrary polygonal 2D cloak with any number of sides can be designed by dividing the polygonal cloak cross section into triangular segments and applying the proposed method on each one. The full wave simulations results confirm the idea performance, properly. Finally, a homogeneous ground invisible cloak for an object, which its contour is very similar to the lateral cross section of a car is designed and simulated to validate the capability and generality of the proposed idea. |
| Author(s): | M. Fazeli, S. H. Sedighy, H. R. Hassani |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 11 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1706 KB |
| Title: | APPLICATION OF EQUIVALENT EDGE CURRENTS TO CORRECT THE BACKSCATTERED PHYSICAL OPTICS FIELD OF FLAT PLATES |
| Abstract: | In the microwave case the physical optics (PO) method is frequently used for the analysis of complex structures which are modeled by flat plates of triangular or quadrangular shape. The study of the radar cross section (RCS) of an isolated panel, however, reveals deviations from experimental results which are due to edge diffraction effects not considered by PO. In order to correct the PO-field by an additive field term, the equivalent fringe currents (EC) of Michaeli have been used to derive the backscattering matrix of an isolated edge. By adding the matrices of the individual edges to the PO-matrix the RCS of a square flat plate with zero and finite thickness is analysed and the result is compared with measurements. The efficiency of the method is demonstrated for objects modeled by a higher number of panels and edges, namely a cylinder and a double dihedral. All computations were performed with the computer code SIG5 of the Institute. [Vol. 7, No. 1, pp. 24-47 (1992)] |
| Author(s): | V. Stein, V. Stein |
| File Type: | Journal Paper |
| Issue: | Volume: 7 Number: 1 Year: 1992 |
| Download Link: | Click here to download PDF File Size: 1217 KB |
| Title: | Analyzing PEC Scattering Structure Using an IE-FFT Algorithm” |
| Abstract: | In this paper a fast integral equation method, termed IE-FFT, is developed, analyzed and applied to the electromagnetic (EM) solution of scattering problems. The methodology is developed for the Method of Moments (MoM) solution of the Electric Field Integral Equation (EFIE) on electrically large Perfect Electric Conducting (PEC) structures. Similar to other Fast Fourier Transform (FFT) based algorithms, IEFFT uses a Cartesian grid to drastically decrease memory storage and speed up the matrix-vector multiplication. The IE-FFT algorithm employs two discretizations, one for the unknown current on an unstructured triangular mesh and the other on a uniform Cartesian grid for interpolating the Green’s function. The uniform interpolation of the Green’s function allows the fast computation of well-separated MoM interaction terms with the aid of a global FFT. Nevertheless, the coupling between near-interaction terms should be adequately corrected. The major contribution of this paper lies on the Lagrangian interpolation of the Green’s function. This not only allows simple and efficient algorithmic implementation, but also naturally suggests a rigorous error analysis of the algorithm. The efficiency of the method is based on the Toeplitz structure of the interpolated Green’s function. Therefore, it is applicable on both asymptotically-smooth and oscillatory kernels arisen in static and wave propagation problems, respectively. Through numerical simulations of electromagnetic wave scattering from a PEC sphere, the complexity of the IE-FFT algorithm is found to scale as O(N1.5) and O(N1.5logN) for memory and CPU time, respectively. Various numerical results verify the high accuracy and efficiency of the method. |
| Author(s): | S. M. Seo, C. Wang, J. F. Lee |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 2 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 595 KB |
| Title: | Analytical Evaluation of Matrix Elements of Electromagnetic Integral Equations with RWG basis Functions for Arbitrarily Oriented Pairs of Triangular Surface Elements |
| File Type: | Conference Paper |
| Issue: | Volume: S51 Integral Equation Solvers for Real-Life Applications II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 207 KB |
| Title: | Analysis of Transient Scattering From Conductors Using Laguerre Polynomials as Temporal Basis Functions |
| File Type: | Journal Paper |
| Issue: | Volume: 19 Number: 2 Year: 2004 |
| Download Link: | Click here to download PDF File Size: 409 KB |
| Title: | Analysis and Synthesis of Equilateral Triangular Ring Microstrip Antenna using Support Vector Machine |
| Abstract: | A support vector machine (SVM) based analysis and synthesis models are presented for the equilateral triangular ring microstrip antennas (ETRMAs) that operate at ultrahigh band applications. The analysis and synthesis of irregularly shaped microstrip antennas (MAs) require complex, lengthy and time consuming mathematical procedures and artificial intelligence techniques such as SVM eliminate great effort and time. In this paper, two models based on SVM are constructed for analysis and synthesis of ETRMAs. The number of 100 ETRMAs with various geometrical and electrical parameters (L, l, h and epsilon r) are simulated in terms of resonant frequency (fr) with the aid of an electromagnetic simulator program to obtain the data set. Two different SVM models are designed to obtain the resonant frequency and slot dimension of ETRMAs by using the simulation data set. The obtaining the resonant frequency and slot size are analysis and synthesis processes, respectively. The SVM models are trained with the simulated data set of 75 ETRMAs and tested with remainders 25 ETRMAs. A prototype of ETRMA is then fabricated to verify the proposed models in this paper. The testing results of the SVM are compared with the simulation/measurement results and the models are found to be successful. Antenna designers can use the proposed models quickly and simply in analysis and synthesis process of ETRMAs without the need for complex processes. |
| Author(s): | A. Kayabasi |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 6 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2028 KB |
| Title: | An MoM Solution for Dielectric Rods of Arbitrary Cross-Section |
| File Type: | Conference Paper |
| Issue: | Volume: Guided Waves in Non-Standard Media Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 58 KB |
| Title: | An Irregular Ground Oriented Miniaturized Antenna for UWB Industrial Applications |
| Abstract: | In this paper, a new small UWB antenna for different UWB industrial applications is presented. The proposed prototype comprises of a simple structure with a modified triangular patch and a sawtooth ground plane. The electrical size of the proposed antenna is 0.15lambda× 0.13lambda×0.014lambda, at lower end frequency. The patch and ground plane is optimized and analyzed. The antenna shows 116% of VSWR<2 impedance bandwidth from 2.8 to 10.5 GHz with a peak gain of 5.6 dBi and 75% of the average radiation efficiency. The proposed design established a nearly omnidirectional radiation characteristic over the operating frequency band. The proposed antenna was successfully simulated, prototyped, and measured. The uniqueness of the proposed antenna is the miniaturization of the antenna for the UWB frequency band, which can be applied for different portable and convenient UWB applications. |
| Author(s): | M. Z. Mahmud, T. Alam, M. Samsuzzaman, A. Ullah, M. T. Islam |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2522 KB |
| Title: | An Efficient Finite-Element Time-Domain Method via Hierarchical Matrix Algorithm for Electromagnetic Simulation |
| Abstract: | An efficient finite-element timedomain (FETD) method based on the hierarchical (H-) matrix algorithm is presented. The FETD method is on the basis of the second-order vector wave equation, obtained by eliminating one of the field variables from Maxwell’s equations. The time-dependent formulation employs the Newmark-beta method which is known as an unconditional stable time-integration method. H- matrix algorithm is introduced for the direct solution of a large sparse linear system at each time step, which is a serious handicap in conventional FETD method. H-matrix algorithm provides a data-sparse way to approximate the LU triangular factors of the FETD system matrix. Using the H-matrix arithmetic, the computational complexity and memory requirement of H-LU decomposition can be significantly reduced to almost logarithmic-linear. Once the H-LU factors are obtained, the FETD method can be computed very efficiently at each time step by the H-matrix formatted forward and backward substitution (H- FBS). Numerical examples are provided to illustrate the accuracy and efficiency of the proposed FETD method for the simulation of three-dimension (3D) electromagnetic problems. |
| Author(s): | T. Wan, R. Chen, J. She, D. Ding, Z. Fan |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 7 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 1082 KB |
| Title: | An Efficient 2D/3D Hybrid DGTD Transient Analysis for Arbitrarily Shaped Anti-Pads in Power-Ground Plate-Pair |
| File Type: | Conference Paper |
| Issue: | Volume: S18 Computational Electromagnetics Advanced Algorithms and Emerging Applications I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 744 KB |
| Title: | An Adaptive and Highly Accurate FDTD Mesh Generation Technique for Objects with Complex Edge Structures |
| Abstract: | In this paper, a triangular facets based, highly accurate, and adaptive finite-difference time-domain (FDTD) mesh generation technique is presented. There are two innovations in the implementation of this technique. One is adaptive mesh lines placement method. The mesh lines are automatically set to be dense where the object has fine structure and sparse where the object has rough structure based on the incremental placement of the triangular mesh vertices. The other is ray column tracing method. Ray columns in the normal direction of the coordinate plane are employed to intersect the surface facets to make the mesh generation results highly accurate. The generating FDTD results of the numerical examples show that the proposed technique can well-restore objects with complex edge structures. The simulation results are in good agreement with the theoretical results. |
| Author(s): | C. Mou, J. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 1 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 7117 KB |
| Title: | Adding a Reproducible Airplane Model tothe Austin RCS Benchmark Suite |
| File Type: | Conference Paper |
| Issue: | Volume: S18 Numerical Methods: Validation, Errors and Accuracy Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 584 KB |
| Title: | Adding a Reproducible Airplane Model to the Austin RCS Benchmark Suite |
| Abstract: | A full-size airplane model (the EXPEDITE-RCS model) was developed as part of a benchmark suite for evaluating radarcross- section (RCS) prediction methods. To generate accurate reference data for the benchmark problems formulated using the model, scale-model targets were additively manufactured, their material properties and RCS were measured, and the measurements were validated with a surface-integral-equation solver. To enable benchmarking of as many computational methods as possible, the following data are made available in a version-controlled online repository: (1) Exterior surface (outer mold line) of the CAD model in two standard file formats. (2) Triangular surface meshes. (3) Measured and predicted monostatic RCS data. |
| Author(s): | J. T. Kelley, A. Maicke, D. A. Chamulak, C. C. Courtney , A. E. Yilmaz |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 11 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1343 KB |
| Title: | A Wideband Circularly Polarized GNSS Antenna for Satellite Platforms |
| File Type: | Conference Paper |
| Issue: | Volume: S46 Physically Reconfigurable Antennas and Arrays: Design, Modeling and Materials II Number: Year: 2019 |
| Download Link: | Login To Download (For Members) File Size: 601 KB |
| Title: | A STUDY OF TWO NUMERICAL SOLUTION PROCEDURES FOR THE ELECTRIC FIELD INTEGRAL EQUATION AT LOW FREQUENCY |
| Abstract: | The numerical solution of the Electric Field Integral Equation (EFIE) using two different lowfrequency formulations is investigated. The two procedures are implemented for the triangular patch modeling procedure and results obtained for both methods are compared with the original triangular patch EFIE solution. The comparisons are made on the basis of the computed current values and the inverse condition number of the moment matrix. It is observed that the condition number of the matrix can be significantly different between the two low frequency formulations and that the method used to evaluate the forcing function can affect the results both in the low and high frequency ranges. [Vol. 10, No. 3 (1995), Special Issue on Advances in the Application of Method of Moments to Electromagnetic Radiation and Scattering Problems, pp 69-80] |
| Author(s): | Wen-Liang Wu, Allen W. Glisson, Darko Kajfez, Wen-Liang Wu, Allen W. Glisson, Darko Kajfez |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 3 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 841 KB |
| Title: | A Straight-Forward Method of Moments Procedure to Solve the Time Domain Integral Equation Applicable to PEC Bodies via Triangular Patch Modeling |
| Abstract: | In this work, a simple and straight-forward method of moments solution (MOM) procedure is presented to obtain the induced current distribution on an arbitrarily-shaped conducting body illuminated by a Gaussian plane wave directly in the time domain using a patch modeling approach. The method presented in this work, besides being stable, is also capable of handling multiple excitation pulses of varying frequency content incident from different directions in a trivial manner. The method utilizes standard Rao-Wilton-Glisson (RWG) functions and simple triangular functions for the space and time variables, respectively, for both expansion and testing. The method adopts conventional MOM and requires no further manipulation invariably needed in standard time-marching methods. The moment matrix generated via this scheme is a block-wise Toeplitz matrix and, hence, the solution is extremely efficient. The method is validated by comparing the results with the data obtained from the frequency domain solution. Several simple and complex numerical results are presented to validate the procedure. |
| Author(s): | S. M. Rao |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 8 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 3321 KB |
| Title: | A Simple Model to Compute Resonant Frequency of an Equilateral Triangular Patch Antenna Backed by Equilateral Triangular Cavity |
| File Type: | Conference Paper |
| Issue: | Volume: S38 EM Modeling and Applications - I Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 255 KB |
| Title: | A Second-Order Stabilized Control Volume Finite Element Method for Self-Heating Effects Simulation of Semiconductor Devices based on Triangular Elements |
| Abstract: | A second-order control volume finite element method combined with the multiscale flux approximation (CVFEM-MS) based on triangular elements is proposed to numerically investigate the selfheating effects of semiconductor devices. The multiscale fluxes are combined with a selected set of second-order vector basis functions to stabilize the discretization of carrier continuity equations with respect to triangular elements. Numerical results reveal that the proposed method is robust and accurate, even on the mesh of low-quality, where the detrimental impacts caused by the severe self-heating on the terminal currents can be obviously observed for a bipolar transistor model. |
| Author(s): | D.-M. Yu, X.-M. Pan, X.-Q. Sheng |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 5 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1344 KB |
| Title: | A Novel Switchable Double Band-Notch Antenna for Ultra-Wideband Application |
| Abstract: | A novel microstrip-fed planar monopole antenna is proposed that is miniaturized in size and provides reconfigurable band-notch properties. The antenna's impedance bandwidth is 150% for VSWR < 2 across 2.6-18.3 GHz, thus satisfying FCC's frequency requirement for UWB systems defined between 3.1-10.6 GHz. To circumvent interference issues resulting from existing nearby communications systems within the UWB operating frequency, the antenna includes an inverted open-loop triangular slot embedded in the hexagonal shaped radiation patch to realize a band-notch response between 3.1 to 3.9 GHz necessary to reject the WiMax band, and open-end resonator structures at both sides of the patch to create a band-notch response between 5.1 to 5.9 GHz, thus enabling band rejection of WLAN and Hyperlink systems. Furthermore, it is demonstrated the band-notch can be electronically controlled without compromising the antenna's characteristic features. This is achieved by strategically located PIN diodes on the antenna. |
| Author(s): | M. N. Moghadasi, S. F. Qotolo |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 10 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 753 KB |
| Title: | A Novel Ray Tracing Method of Creeping Waves on Triangular Mesh Surfaces |
| File Type: | Conference Paper |
| Issue: | Volume: 3-4-A Multi-Physics Modelling and Time-Domain and Frequency-Domain Computational Methods Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 806 KB |
| Title: | A Novel Domain Decomposition Method Decoupled Hybrid 2D/Q-2D Finite Element Method for Power/Ground Plate-Pair Analysis |
| File Type: | Conference Paper |
| Issue: | Volume: 3-MA-3 Advances in Numerical Modeling and Design Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 83 KB |
| Title: | A Novel Dielectric Loaded Vivaldi Antenna with Improved Radiation Characteristics for UWB Application |
| Abstract: | In this paper, a compact (40×50×0.8mm3) Vivaldi antenna with trapezoidal corrugation and a triangular director element is proposed for high gain performance. The exponential slot with diamond slot stub is designed to broaden the bandwidth. The measured bandwidth is 11.3 GHz from 2.9 to 14.2 GHz under the condition of Voltage Standing Wave Ratio (VSWR) less than 2. The simulated gain is 5.5-9 dBi at the full bandwidth. The measured gain is 5-7.6 dBi from 3 to 5.8 GHz. In addition, the measured group delay of the proposed antenna is around 2±0.8 ns. The simulated and measured results agree well. |
| Author(s): | H. Zhu, X. Li, L. Yao, J. Xiao |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 4 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2058 KB |
| Title: | A New UWB Slot Antenna with Rejection of WiMax and WLAN Bands |
| Abstract: | This paper presents a compact coplanar waveguide (CPW) fed ultra wideband (UWB) planar slot antenna with the characteristics of dual band rejection. The antenna consists of a rectangular slot with triangular tuning stub. The band notching of WiMax (3.2-3.8 GHz, with VSWR 68 at 3.5 GHz) is achieved by inserting a ‘U’ slot in the ground plane and band-notching of WLAN 802.11a (5.1-5.9 GHz, with VSWR 14 at 5.5 GHz) is obtained by embedding a ‘U’ type slot in the triangular tuning stub. The characteristics of the proposed antenna are studied both numerically and experimentally, and the design parameters for achieving optimal operation of the antennas are also analyzed extensively. The size of the antenna is around 28mm (L) × 21mm (W) × 1.6mm (T). The prototype of the proposed antenna is fabricated for its optimal values and tested. The VSWR, radiation pattern and gain are measured and agree well with the simulation results. The proposed antenna is simple, easy to fabricate and can be integrated into any UWB system, which can work without interference from WiMax, WLAN, and HYPERLAN/2 systems. |
| Author(s): | J. William, R. Nakkeeran |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 9 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 646 KB |
| Title: | A Mortar Element Method for the Modelling of Scattering by Penetrable Objects |
| File Type: | Conference Paper |
| Issue: | Volume: Fast Integral Equation Methods and Stable Discretization Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 673 KB |
| Title: | A General Framework for Mixed Structured/Unstructured PEEC Modelling |
| Abstract: | The paper proposes a re-formulation of PEEC modeling in terms of dual discretization of surface conductors. The result is a precise formalization of the PEEC tessellation and gives the possibility of handling general meshes, both structured and unstructured. This fact allows the use of triangular meshes only where necessary, leaving orthogonal discretization whenever possible and improving computational performances. The method, referred to as dual-PEEC, is validated by solving a structure referenced in literature and finally applied to the computation of the input impedance of a spiral inductor. |
| Author(s): | F. Freschi, M. Repetto, F. Freschi, M. Repetto |
| File Type: | Journal Paper |
| Issue: | Volume: 23 Number: 3 Year: 2008 |
| Download Link: | Click here to download PDF File Size: 608 KB |
| Title: | A General Framework for Mixed Structured/Unstructured PEEC Modelling |
| File Type: | Conference Paper |
| Issue: | Volume: Advanced EMC Modeling Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 645 KB |
| Title: | A Finite-Element Contrast Source Inversion Method for Microwave Tomography |
| File Type: | Conference Paper |
| Issue: | Volume: Efficient Solutions to Inverse Electromagnetic Problems Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 2157 KB |
| Title: | A Comprehensive 2D FE-SIBC Model for Calculating the Eddy Current Losses in a Transformer Tank-Wall |
| Abstract: | The calculation of the eddy-current losses is one of the most important aspects that must be considered in the design of transformers and electrical machines. In this paper, a comprehensive 2D finite element (FE) model for calculating the eddy-current losses in a tank-wall of the transformer is presented. The FE model takes into account the Surface Impedance Boundary Condition (SIBC). A detailed 2D-SIBC formulation in terms of the magnetic vector potential is described. The SIBC is incorporated into the FE formulation by using the Galerkin method. An axi-symmetric electromagnetic model of the transformer is solved by applying the SIBC formulation for calculating the loss intensity distribution along the vertical tank-wall. To demonstrate the validity of the SIBC formulation, the results are compared against those computed with a model based on first-order triangular elements. The advantages of using the SIBC formulation in the modeling of power transformers are highlighted. |
| Author(s): | J. M. Díaz-Chacón, C. Hernandez, M. A. Arjona |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 8 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 759 KB |
| Title: | A Comparison Among Fast Visibility Algorithms Applied to Computational Electromagnetics |
| Abstract: | This paper presents a set of fast algorithms developed for solving the visibility problem in large complex geometric scenarios. The implemented algorithms are: Binary Space Partitioning (BSP) –based on a binary tree structure- and three new ones: Trimming Method – facets which are partially occluded are trimmed –, Cone Method – a cone emerges from the point of view to discard shadowed facets – and Pyramid Method – a pyramid is used to eliminate non-lit patches – . All the proposed algorithms are tested on a pair of scenarios for determining the field of view of electromagnetic waves in order to calculate the corresponding induced currents on the surfaces. The scenarios consist of two electrically large spheres and two PEC plates respectively where the surfaces are meshed with a variable number of flat triangular patches. The first reflection contribution is calculated using Physical Optics (PO) for both cases. The results show that the computational time can be drastically reduced by assuming small percentage of error in the computed scattered fields. |
| Author(s): | J. G. Meana, F. Las-Heras, J. Á. Martínez-Lorenzo |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 3 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 597 KB |
| Title: | A Compact UWB Printed Monopole Antenna with Triple-Band Notched Characteristics |
| Abstract: | A compact triple band-notched printed monopole antenna for ultra-wideband (UWB) application is presented. By inserting two triangular-shaped notches in both sides of the ground plane of microstrip feed line, additional resonances are excited and the bandwidth is increased up to 160%. Three sharp notched frequency bands at 3.8 GHz, 5.5 GHz, and 7.5 GHz are achieved by embedding a pair of rectangularshaped slits in the ground plane and two pairs of modified bow-shaped slits in the patch. This novel monopole antenna has ultra-wide frequency bandwidth for input impedance, compact size (24 mm × 20 mm), low cost fabrication and Omnidirectional H-plane radiation pattern which makes it suitable for ultra-wideband applications. The measured results reveal that the presented triple band-notched monopole antenna is a promising candidate for UWB communication systems to avoid interference with WiMax band (3.3-3.7 GHz), some C-band (3.7-4.2 GHz), WLAN (5.15- 5.825 GHz) bands and some C-band satellite communication systems (7-8 GHz). |
| Author(s): | A. Abdollahvand, A. Pirhadi, M. R. Hosseinnezhad, H. Ebrahimian |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 4 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 2540 KB |
| Title: | A Compact High Gain Multiband Bowtie Slot Antenna with Miniaturized Triangular Shaped Metallic Ground Plane |
| Abstract: | This paper presents a new compact, high gain and multiband planar bowtie slot antenna. The antenna structure comprises of dielectric substrate, copper conducting sheet, fillet triangular-shaped slots, and a chamfered metallic ground plane. The proposed antenna model is fed with the 50 Ω standard grounded coplanar waveguide (GCPW) feedline. The designed antenna is low profile with compact dimensions of 0.379λ×0.186λ×0.012λ at 2.39 GHz frequency. Stable multi-resonant behavior of frequencies is obtained with the material selection, slots dimensions and position. Moreover, the parametric study has been carried out in order to validate the frequency tuning mechanism and impedance matching control. The novelty of designed antenna lies in high performance features which have been achieved with ultra-compact (0.039λ×0.022λ) modified triangular shaped metallic ground plane. The proposed antenna is fabricated and experimentally verified. The antenna key features in terms of return loss, surface current distribution, peak gain, radiation efficiency and radiation patterns have been analyzed and discussed. The designed radiator exhibits the excellent performance including strong current density, peak realized gain of 6.3 dBi, 95% radiation efficiency, wide fractional bandwidth of 39.5% and good radiation characteristics at in-band frequencies. The simulation and measured results are in good agreement and hence make the proposed antenna a favorable candidate for the advanced heterogeneous wireless communication applications. |
| Author(s): | Z. A. Dayo, Q. Cao, Y. Wang, P. Soothar, I. A. Khoso, G. Shah, M. Aamir |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 7 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1933 KB |
| Title: | A Compact Frequency Reconfigurable Split Ring Monopole Antenna for WLAN/WAVE Applications |
| Abstract: | A novel frequency reconfigurable dual band monopole antenna based on the triangular split ring element is proposed for wireless communications. The antenna with an overall compact size of 25×25×1.6 mm3 is designed for the operating frequencies of wireless local area network (WLAN) 2.4/5.0 GHz standard and wireless access for vehicular environments (WAVE) 5.90 GHz standard. The parametric study is carried out for tuning the upper resonant frequency. The reconfigurability between the WLAN and WAVE frequency bands is achieved by using a pair of PIN diode. The design considerations for the proposed antenna are described and the experimental results are validated. The antenna exhibits almost uniform radiation characteristics and good gain at each frequency band with the -10 dB impedance bandwidth of 44.1%, 5.8% and 10.1% at 2.45/5.30/5.90 GHz WLAN and WAVE bands respectively. |
| Author(s): | V. Rajeshkumar, S. Raghavan |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 3 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 598 KB |
| Title: | A Compact Design and New Structure of Monopole Antenna with Dual Band Notch Characteristic for UWB Applications |
| Abstract: | In this paper, a compact design and new structure of monopole antenna with dual band notch characteristics for UWB applications has been presented. The antenna consists of a triangular patch with C-shaped slot, two L-shaped and one split ring shaped parasitic backplane elements structure. By inserting three slots in the rectangular truncated ground plane as defected ground structures (DGSs), much wider impedance bandwidth can be produced, and moreover to improve the input matching quality of the antenna at all its operating bands which are spread in a vast frequency range, a modified stepped feed-line is employed. These changes much improves the antenna’s impedance bandwidth by 112% which covers the entire UWB bandwidth range. In order to generate single band notch characteristic, split ring shaped parasitic element backplane structure is utilized on the ground plane side of the substrate. In addition, by etching a C-shaped slot on the radiating patch, a dual band notch function is achieved. The measured frequency results show an impedance bandwidth of 3.15-10.78 GHz for a Voltage Standing Wave Ratio (VSWR) less than 2 with two eliminated bands placed at 3.49-3.81 GHz (320 MHz, 8.8%) and 5.24-6.22 GHz (980 MHz, 17%), which reject the WiMAX band, and Wireless Local Area Network (WLAN) band, respectively. A prototype was fabricated and measured based upon optimal parameters and experimental results show consistency with simulation results. The measured radiation patterns of proposed antenna for most frequencies are omnidirectional and this antenna as wide impedance bandwidth. |
| Author(s): | S. Hoseyni, J. Nourinia, C. Ghobadi, S. Masumina, B. Mohammadi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 7 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2108 KB |
| Title: | A Broadband Reflectarray Antenna using the Triangular Array Configuration |
| Abstract: | A novel broadband reflectarray cell element is designed for use in several offset-fed reflectarray antennas based on square and triangular lattice. The proposed double-layer element consists of two stacked rectangular patches having two slots in non-radiating edges. Reflection phase curves are obtained by changing simultaneously the slot’s length of top and bottom patch. The designed element exhibits a large phase-shift range in excess of 360o.This wideband cell element is designed to be used in a triangular lattice that eliminates the grating lobes for wideband reflectarrays composed of unit-cell larger than half-wavelength. Two 529-element square reflectarrays and two 518-element triangular reflectarray antennas were designed and simulated using CST and HFSS, for producing 20o and 35o off-broadside E-plane beams using a 20o offset feed. The 1-dB gain-bandwidth is about 30% at the center frequency of 14 GHz, and the maximum simulated gain is about 31 dBi which is equivalent to 51.5% aperture efficiency for a 20o off-broadside reflectarray based on triangular lattice configurations. |
| Author(s): | M. Mohammadirad, N. Komjani, A. R. Sebak, M. R. Chaharmir |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 8 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 880 KB |
| Title: | 25 Years of Progress and Future Challenges in Higher Order Computational Electromagnetics |
| File Type: | Conference Paper |
| Issue: | Volume: 25 Years of Progress and Future Challenges in Applied Computational Electromagnetics II Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 179 KB |
| Title: | VERIFYING WIRE-GRID MODEL INTEGRITY WITH PROGRAM 'CHECK' |
| Abstract: | A wire-grid model of a complex surface such as an aircraft consists of hundreds of "vertex" points joined by hundreds of wires or "links". A wire antenna analysis program such as NEC is used to find the currents on the wires. The formulation within NEC imposes restrictions on the geometry of the wires, which limit the length of "segments" compared to the wavelength, the radius compared to the wavelength, the ratio of the segment length to the radius, and so forth. This paper collects these limitations together into a set of "modeling guidelines". The"integrity" of a wire-grid is its ability to represent the electrical behaviour of the continuous surface that it models. An important aspect of integrity is conformance to the "modeling guidelines". Gross errors creep into complex grids: repeated wires, omitted wires, wires of zero length. More subtle errors which violate the "modeling guidelines" can lead to incorrect current distributions and misleading radiated or scattered fields form the wire-grid when solved with the NEC code. This paper describes a program called CHECK which examines an input geometry file for the NEC program for conformance to the "modeling guidelines" by each individual wire, by wires forming junctions, and by pairs which do not join but are closely spaced. CHECK tabulates "notes", "warnings" and "errors" to aid the user in assessing the degree to which the model satisfies the guidelines. CHECK systematically finds all the guideline violations in a model. CHECK produces lists of wires for display with computer graphics to show the location of each type of problem that CHECK finds. The guideline violations found by CHECK inherently suggest improvements that can be made to the wire-grid. [Vol. 5, No. 2. pp. 17-42 (1990)] |
| Author(s): | C. W. Trueman, S. J. Kubina, C. W. Trueman, S. J. Kubina |
| File Type: | Journal Paper |
| Issue: | Volume: 5 Number: 2 Year: 1990 |
| Download Link: | Click here to download PDF File Size: 1753 KB |
| Title: | \"Introduction to Antennas\" – an antenna training DVD |
| File Type: | Conference Paper |
| Issue: | Volume: CEM for Applied Analysis and Synthesis Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 350 KB |
| Title: | \"Capacity estimation of HF ionospheric Channel\" |
| File Type: | Conference Paper |
| Issue: | Volume: Posters Session 2 Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 352 KB |
| Title: | Zooming into the Near-fields: Embedding Generalized- and Pseudo-functions in the Solution Space of Maxwell's Equations |
| File Type: | Conference Paper |
| Issue: | Volume: Mathematical Aspects of CEM Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 330 KB |
| Title: | Z-diagonalized Planewave/FD Approach for Analyzing TE Polarized Waves in 2D Photonic Crystals |
| File Type: | Conference Paper |
| Issue: | Volume: FDTD Methods and Applications Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 300 KB |
| Title: | Yee-based 3D electromagnetic algorithm for discontinuous anisotropic dielectrics with global 2nd-order error |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Finite Difference Time Domain Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 138 KB |
| Title: | X-Band Linear Dielectric Resonator Antenna Array Fed by Dielectric Resonator Power Divider Array |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Phased Array Modeling Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 486 KB |
| Title: | X-Band Isoflux Concentric Circular Antenna Arrays for Image Data Download from LEO Satellites to Ground Stations |
| Abstract: | A circularly polarized isoflux beam synthesized by concentric circular arrays of printed microstrip patch antennas is proposed for X-band transmission of image data from land-imaging LEO satellites to the ground stations. This beam has a wide coverage angle of about 100° of uniform illumination. The paper introduces a novel design of a compact righthand circularly polarized microstrip patch as an element for the concentric circular arrays. The patch antenna has impedance matching bandwidth of about 600 MHz and axial ratio bandwidth of about 170 MHz at 8.1 GHz. A prototype of the proposed patch antenna is fabricated for experimental measurements. The electromagnetic simulation and experimental results show good agreement. A computationally efficient particle swarm optimization (PSO) procedure is developed and applied to find the distribution of the excitation magnitudes over the array elements so as to generate an isoflux beam in all the elevation planes with circular symmetry in the azimuth planes. The phase of excitation is the same for all the array elements. The method proposed to apply the PSO reduces the computational resources to about 6.5% of those required by the conventional method of application. Moreover, the proposed iterative PSO procedure is shown to be very fast convergent. |
| Author(s): | M. A. El-Hassan, K. F. A. Hussein, A. E. Farahat, K. H. Awadalla |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1802 KB |
| Title: | Wrapping Existing Electromagnetic Code into an Object-Oriented Scripting Programming Language |
| File Type: | Conference Paper |
| Issue: | Volume: Object Oriented Computational Electromagnetics Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 151 KB |
| Title: | Women’s History Month Special Article: Interview with “Professor Ozlem Kilic” |
| Abstract: | The month of March is Women’s History Month. We all have heard and know that only a small percentage of electrical engineers are female. This percentage is even smaller for those that are experts in the field of applied computational electromagnetics. In this article, we are focusing on Dr. Ozlem Kilic, one of the well-known and established intellectuals in the field of computational electromagnetics. Dr. Kilic not only has been a role model for young students as an excellent researcher, a technical leader, and a prolific writer in this field, but also she has extensive experience in teaching and has taken many academic administration roles. |
| Author(s): | S. Noghanian |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 3 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 398 KB |
| Title: | WLP-FDTD Implementation of CFS-PML for Plasma Media |
| File Type: | Conference Paper |
| Issue: | Volume: S19 Finite-Difference Time-Domain Method: Theory and Applications Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 181 KB |
| Title: | WLAN Based Indoor Positioning in Building Halls by Using Trilateral |
| File Type: | Conference Paper |
| Issue: | Volume: S23 RF/Microwave Electromagnetics - Computational Modeling and Experiments Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 309 KB |
| Title: | Wireless Propagation in Non Line of Sight Urban Areas using Uniform Theory of Diffraction |
| Abstract: | This paper describes a three-dimensional electromagnetic propagation model for signal power prediction in a non line of sight urban area located in Singapore. The model, which is implemented using the Ohio State NEC-BSC V4.2 basic scattering code and is based on ray theory and uniform theory of diffraction (UTD) takes into account first, second, and third order effects including triple reflections and diffractions. The simplified propagation model of Raffles Place, the central business district of Singapore, uses more than 360 geometrical structures and is compared with data measured at 937.6 MHz along a drive route at the site. The results from the propagation model produced reasonable agreement with the measurements showing that a simplified model using UTD can be used to simulate the gross features of electromagnetic scatter in an urban area. It is shown that use of penetrable dielectric building walls are also necessary for accurate prediction of radio wave propagation in urban areas under non line of sight conditions. It is also found that third order scattering effects can be dominant in non line of sight situations and may be necessary for accurate predictions. |
| Author(s): | G. A. Ellis, G. A. Ellis |
| File Type: | Journal Paper |
| Issue: | Volume: 18 Number: 3 Year: 2003 |
| Download Link: | Click here to download PDF File Size: 126 KB |
| Title: | Wireless Power Transfer via Negative Permittivity Metamaterials as Resonating Elements |
| File Type: | Conference Paper |
| Issue: | Volume: S42 Wireless Power Transfer Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 252 KB |
| Title: | Wireless Power Transfer Using Magneto-Electric Dipoles |
| File Type: | Conference Paper |
| Issue: | Volume: S37 Wireless Power Transfer and Energy Harvesting: Advances in Modelling and Practice Number: Year: 2019 |
| Download Link: | Login To Download (For Members) File Size: 245 KB |
| Title: | Wireless Power Transfer to Closely Coupled Loop Antennas Embedded in Concrete for Sensing |
| File Type: | Conference Paper |
| Issue: | Volume: Wireless Powering of Devices & Energy Harvesting Number: Year: 2014 |
| Download Link: | Login To Download (For Members) File Size: 235 KB |
| Title: | Wireless Energy Harvesting Using a Negatively Charged UV Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: 3-3-D Wireless Power Transfer and Harvesting Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 230 KB |
| Title: | Wireless Communication Applications of the Continuous Transverse Stub (CTS) Array at Microwave and Millimeter Wave Frequencies. |
| File Type: | Conference Paper |
| Issue: | Volume: Phased Array and Active Antennas Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 915 KB |
| Title: | Wireless Communication Antennas: Special Requirements And New Designs of Dielectric Resonator Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: Poster Sessions 1 Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 108 KB |
| Title: | Wireless Body Area Networks: UWB Antenna design and Channel Modeling |
| File Type: | Conference Paper |
| Issue: | Volume: S19 Biomedical Applications Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 2905 KB |
| Title: | WIREGRID: A NEC2 PRE-PROCESSOR |
| Abstract: | WIREGRID is a pre-processor for the widely used public domain method of moments computer code NEC2. WIREGRID was developed for modelling metallic structures using a mesh of wires. In particular, it has powerful facilities for controlling the density of the mesh, permitting the same basic model to be used for different frequencies, with the code automatically generating a suitable mesh for a particular frequency. WIREGRID is not limited to generating wire meshes: it can also be usefully applied to true thin-wire modelling, for instance for Yagi-Uda and log-periodic antennas. In this paper, the basic philosophy of the code is described, and the code capabilities are detailed. Sufficient detail is presented so that the paper can serve as a reference for code users. The meshing algorithm is briefly described. An example is shown of the automatic mesh generation capabilities applied to an automobile. WIREGRID is available in the public domain via anonymous ftp; details of the ftp sites and hardware requirements are given in the appendices. [Vol. 10, No. 1 (1995), pp 31-39] |
| Author(s): | C. F. du Toit, D.B. Davidson, C. F. du Toit, D.B. Davidson |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 1 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 844 KB |
| Title: | WIRE-GRID MODELING OF SLOT ANTENNAS |
| Abstract: | The ability of a computer code to model slot antennas is investigated. A comparison of experimental and numerically calculated antenna data is presented. [Vol. 1, No. 1, pp.6-14 (1986)] |
| Author(s): | Jimmy L. Funke, Jimmy L. Funke |
| File Type: | Journal Paper |
| Issue: | Volume: 1 Number: 1 Year: 1986 |
| Download Link: | Click here to download PDF File Size: 1140 KB |
| Title: | Wire Realization of a Tapered Slot Antenna with Reconfigurable Elements |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Simulation using FEKO Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 504 KB |
| Title: | Wire Grid Moment Method (NEC) Models of a Patch Antenna |
| Abstract: | Wire grid models of an air-loaded resonant circular patch antenna are used to calculate several observable quantities. The resonant frequency, input reactance, and bandwidth are accurately calculated, but the input resistance is underestimated by the grid models due to the existence of separate currents on both the top and bottom of the measured solid patch. The Lawrence Livermore (NEC3) Method of Moments computer program was used to generage the grid models. Averge wire lengths of about 0.03 wavelengths are required for accurate results. A comparison with other studies suggests that the 0.03 wavelength segmentation may be required because the patch is close to the ground plane (0.0175 wavelengths), and/or because errors in the near field calculation are compounded by the large fraction of energy stored in the near field since the patch is a high Q resonator. |
| Author(s): | P.G. Elliot, S.T. McBride, P.G. Elliot, S.T. McBride |
| File Type: | Journal Paper |
| Issue: | Volume: 4 Number: 3 Year: 1989 |
| Download Link: | Click here to download PDF File Size: 703 KB |
| Title: | Wire Fault Diagnosis Using Time-Domain Reflectometry and Backtracking Search Optimization Algorithm |
| File Type: | Conference Paper |
| Issue: | Volume: S43 Inverse Finite Element Optimization in Electromagnetic Product Design and Non-Destructive Evalutation II Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 251 KB |
| Title: | Wire Fault Diagnosis Based on Time-Domain Reflectometry and Backtracking Search Optimization Algorithm |
| Abstract: | The development of a robust and accurate fault diagnosis approach under various system and fault conditions is a research area of great interest. The objective of this paper is to develop a new non-destructive approach for wiring diagnosis based on Time Domain Reflectometry (TDR) in one hand and on Backtracking Search Optimization Algorithm (BSA) in the other hand. Real-world case studies are investigated to demonstrate the effectiveness and robustness of the proposed approach. Simulation results evaluated from experimental data demonstrate that the proposed approach can be used for effective diagnosis of complex wiring networks. |
| Author(s): | H. Boudjefdjouf, H. R. E. H. Bouchekara, F. de Paulis, M. K. Smail, A. Orlandi, R. Mehasni |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 4 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 723 KB |
| Title: | WIPL-D Results and Time Domain Response for an Impulse Radiating Antenna (IRA) |
| File Type: | Conference Paper |
| Issue: | Volume: Special Session: Electromagnetic Modeling by WIPL-D Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 0 KB |
| Title: | WIPL-D Results and Time Domain Response for an Impulse Radiating Antenna (IRA) |
| File Type: | Conference Paper |
| Issue: | Volume: Special Session: Electromagnetic Modeling by WIPL-D Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 193 KB |
| Title: | WIPL-D Parallelization Effort |
| File Type: | Conference Paper |
| Issue: | Volume: Special Session: Electromagnetic Modeling by WIPL-D Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 117 KB |
| Title: | WIPL-D Optimization of a Harmonic RF Tag |
| File Type: | Conference Paper |
| Issue: | Volume: EM Applications Using WIPL-D Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 340 KB |
| Title: | WIPL-D Model and Simulation Results for a 6ft Diameter Impulse Radiating Antenna (IRA) |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Electromagnetic Modeling by WIPL-D Software Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 148 KB |
| Title: | WIPL-D Compared to Other EM Codes for the Analysis of Printed Antennas |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Modeling by WIPL-D Code Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 431 KB |
| Title: | WIPL Code Validation for Metallic Structures |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Modeling by WIPL-D Code Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 253 KB |
| Title: | Wind Turbine RCS Modeling and Validation* |
| File Type: | Conference Paper |
| Issue: | Volume: Topics in Radar Scattering Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 201 KB |
| Title: | Wind Power Axial-Flux PM Generator Loss Computation Using Quasi-3D FEA |
| File Type: | Conference Paper |
| Issue: | Volume: S07 Low Frequency Magnetics Number: Year: 2016 |
| Download Link: | Login To Download (For Members) File Size: 779 KB |
| Title: | Wideband, Scanning Array for Simultaneous Transmit and Receive |
| File Type: | Conference Paper |
| Issue: | Volume: S19 Broadband Antennas and Applications Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 322 KB |
| Title: | Wideband Single Arm Spiral Antennas |
| File Type: | Conference Paper |
| Issue: | Volume: S14 EM Modeling using FEKO - II Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 478 KB |
| Title: | Wideband Self-adjoint Jacobian Computation with Time-domain Field Solutions |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Modeling with QuickWave/Concerto Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 210 KB |
| Title: | Wideband Quasi-Yagi Antenna with Broad-Beam Dual-Polarized Radiation for Indoor Access Points |
| Abstract: | This paper presents a wideband, broad beamwidth, dual-polarized antenna for the indoor access points. Its primary radiating elements are two quasi-Yagi antennas, which are arranged orthogonally. The antenna element employs two balanced directors to broaden bandwidth and avoid the structural conflict of the orthogonal installation. A microstrip-slotline transformer is used in the feeding structure for allowing the wideband operation and high port-to-port isolation. The dualpolarized quasi-Yagi antenna is incorporated with a metallic cavity in order to improve the unidirectional radiation in terms of gain, front-to-back ratio, and beamwidth. The final prototype has been fabricated and tested. The antenna yielded a wide impedance bandwidth covering a frequency range from 1.64 to 3.0 GHz (60%) for both ports with port-to-port isolation of a higher than 25 dB. In addition, at both ports, the antenna achieves stable unidirectional radiation with broad beamwidth, high front-to-back ratio, and high radiation efficiency. |
| Author(s): | S. X. Ta, C. D. Bui, T. K. Nguyen |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 5 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1560 KB |
| Title: | Wideband Printed Lotus Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: Wideband Antennas Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 283 KB |
| Title: | Wideband Printed CPW-fed Binomial Curved Slot Antennas |
| File Type: | Conference Paper |
| Issue: | Volume: Antenna Modeling and Small Antennas Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 250 KB |
| Title: | Wideband Printed Antipodal Vivaldi Antenna using Straight Slots for UHF DVB-T/T2 Applications |
| Abstract: | This paper presents a wideband printed antipodal Vivaldi antenna using straight slots for UHF DVB-T/T2 applications covering a frequency range of 470–862 MHz. The proposed antenna consists of two radiation flares with straight slots and a feeding line. A wideband impedance matching was achieved by inserting the slots between the flares and the feeding line. For the experimental verification of the proposed antenna, it was fabricated on a flat circular printed circuit board (PCB) substrate with a radius of 0.25 λ0, where λ0 is the wavelength at 0.74 GHz (the center frequency of the operating band). The measured −10 dB impedance bandwidth and maximum gain were approximately 72.1% (0.47–1.00 GHz) and 2.57 dBi, respectively. Due to the addition of the slots, the impedance bandwidth of the proposed antenna was improved by approximately 212% compared with the Vivaldi antenna without slots. |
| Author(s): | N.-R. Kwon, S.-H. Ahn, W.-S. Lee |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 6 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 4821 KB |
| Title: | Wideband Power Divider Using Novel Split-Ring Resonator |
| Abstract: | A set of novel split-ring resonator basic block Hybrid-Microwave Integrated-Circuit (HMIC) components (transmission line, open and short stubs) is presented with applications to the RF/Microwave power divider. This new open and short LH HMIC resonators have compact sizes of 0.81 and 1.44 mm2 , respectively. The prototypes of an LH power divider constructed from these basic components have been designed, fabricated, and characterized. The LH power divider including two LH branches shows equal power split from 1 to 7 GHz. The proposed power divider benefit from the miniaturized LH HMIC components and have compact sizes of 2.205 mm2 , respectively. There is a good agreement between the full-wave simulations and measurement results with 0.254-mm thick RT5880 substrate. While maintaining similar performance, a 50% reduction in impedance transformer is achieved in comparison to a conventional design. |
| Author(s): | T. Huang, D. Jiang, H. Hu |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 2 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 235 KB |
| Title: | Wideband Planar Slot Antennas |
| File Type: | Newsletter Paper |
| Issue: | Volume: 19 Number: 1 Year: 2004 |
| Download Link: | Click here to download PDF File Size: 363 KB |
| Title: | Wideband Open Sleeve Dipole Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: S45 UWB and Multi-Band Antennas II Number: Year: 2016 |
| Download Link: | Login To Download (For Members) File Size: 720 KB |
| Title: | Wideband Octagonal Dual Circularly Polarized Sub-array Antenna for Ku-Satellite Systems |
| Abstract: | In this paper the analysis and design of a dual circularly polarized 4×4 antenna array operating in Ku-band are discussed with emphasis on its sequential feeding network. The dual circular polarization is achieved by feeding a stacked octagonal patches with a wideband branch line coupler. The proposed 4×4 antenna array is based on two separate sequential feeding networks for LH and RH circular polarizations. The advantage of the proposed feeding network is that it is implemented on a single layer. Simulation results by using both HFSS and CST are presented for comparison. In addition, experimental verifications are presented. |
| Author(s): | K. M. Ibrahim, W. M. Hassan, E. A. Abdallah, A. M. Attiya |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 12 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1254 KB |
| Title: | Wideband Multi-Port Network Integrated by 3-dB Branch-Line Couplers |
| Abstract: | The design of a multi-port network integrated by symmetrical alignment of four 3-dB branch-line couplers (BLCs) for wideband communication applications is presented. The BLC is designed with the implementation of stub impedance at each port’s transmission line and defect ground structure (DGS) underneath the shunt branches of BLC to improve bandwidth. The designs of the BLC and the multi-port network are performed by using CST Microwave Studio, a three-dimensional (3D) electromagnetic wave simulator. The designed wideband BLC and multi-port are fabricated, and their wideband performances of 2.3 to 5.3 GHz are verified. |
| Author(s): | N. A. M. Shukor, N. Seman, T. A. Rahman |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 7 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2248 KB |
| Title: | Wideband MIMO Directional Antenna Array with a Simple Meta-material Decoupling Structure for X-Band Applications |
| Abstract: | In this paper, a compact wideband MIMO directional antenna array with a single-layered meta-material is proposed to realize high isolation. The meta-material decoupling structure, which is composed of a modified split-rings and a square loop structure, is suspended over the two antenna elements to reduce the mutual coupling. The achieved results show that the proposed antenna array owns a −10 dB impedance bandwidth ranging from 8.5 GHz to 11.5 GHz. Furthermore, by loading the proposed meta-material superstrate over the two-element MIMO antenna, the designed MIMO antenna array not only has good performance but also enhances the isolation to be more -15 dB within the operating frequency band. In addition, the performances of the proposed antenna array are also tested by radiation pattern, gain, envelope correlation coefficient, diversity gain, total active reflection coefficient and so on. Therefore, these simulation results prove that the proposed wideband MIMO directional antenna array is a suitable candidate for X-band communication. |
| Author(s): | J. Jiang, Y. Li, L. Zhao, X. Liu |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 5 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 21801 KB |
| Title: | Wideband Microstrip Patch Antennas with Transverse Electric Modes |
| Abstract: | A wideband microstrip patch antenna, exciting the fundamental transverse electric (TE) mode, is investigated. The excitation of the TE mode is facilitated through replacing both of the patch and ground plane of a conventional microstrip antenna with artificial magnetic conductors (AMC), consisting of unipolar compact photonic bandgap (UC-PBG) unit cells. The AMC patch and the ground plane of this antenna behave as magnetic conductors within the bandgap region of the unit cells. Similar to conventional patch antennas, it is shown that by cutting a U-shaped slot in the AMC patch, wideband characteristics are realized. The antenna shows a 40% impedance bandwidth and operates at the TE10 mode. Moreover, the width of the patch is 1.75 times smaller than its length, reducing the overall size of the antenna by about 60%, compared with the conventional U-slot PEC antenna supporting the transverse magnetic (TM) mode. |
| Author(s): | T. Mitha, M. Pour |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 8 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1356 KB |
| Title: | Wideband Microstrip Patch Antennas with Transverse Electric Modes |
| Abstract: | A wideband microstrip patch antenna, exciting the fundamental transverse electric (TE) mode, is investigated. The excitation of the TE mode is facilitated through replacing both of the patch and ground plane of a conventional microstrip antenna with artificial magnetic conductors (AMC), consisting of unipolar compact photonic bandgap (UC-PBG) unit cells. The AMC patch and the ground plane of this antenna behave as magnetic conductors within the bandgap region of the unit cells. Similar to conventional patch antennas, it is shown that by cutting a U-shaped slot in the AMC patch, wideband characteristics are realized. The antenna shows a 40% impedance bandwidth and operates at the TE10 mode. Moreover, the width of the patch is 1.75 times smaller than its length, reducing the overall size of the antenna by about 60%, compared with the conventional U-slot PEC antenna supporting the transverse magnetic (TM) mode. |
| Author(s): | T. Mitha, M. Pour |
| File Type: | Express Journal Paper |
| Issue: | Volume: 35 Number: 8 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 410 KB |
| Title: | Wideband Microstrip Patch Antenna at 7 GHz |
| File Type: | Conference Paper |
| Issue: | Volume: Student Microwave Design Projects with Sonnet Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 211 KB |
| Title: | Wideband Microstrip Endfire Antenna based on SIW and Magnetic Dipole |
| File Type: | Conference Paper |
| Issue: | Volume: 1-P1-C Wideband and Multiband Antennas Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 420 KB |
| Title: | Wideband LTCC Vertical-Fed Dipole Antenna for Millimeter-Wave Applications |
| File Type: | Conference Paper |
| Issue: | Volume: 2-2-B Millimeter Wave and Terahertz Antennas Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 529 KB |
| Title: | Wideband Low Profile Multi-Polarization Reconfigurable Antenna with Quasi-cross-shaped Coupling Slot |
| Abstract: | A wideband low profile multi-polarization reconfigurable antenna with quasi-cross-shaped coupling slot is proposed. The antenna consists of an upper oval radiating patch, the quasi-cross-shaped coupling slot, fork-shaped folded feed lines and a reconfigurable Wilkinson power divider network with four pairs of p-in diodes. The antenna reconfigurable polarization modes change among ±45° Linear polarization (LP), dual-LP, left-hand circular polarization (LHCP) and right-hand circular polarization (RHCP) by controlling the ON/OFF states of the p-i-n diodes. The designed prototype has been fabricated and measured. Good agreement between the measured and simulated results is achieved. Measured results show that the antenna has wide impedance bandwidth (over 21.35% for LP and 17.70% for CP) and axial ratio (AR) bandwidth (16.13% for LHCP and 16.88% for RHCP). The average realized gains are about 7.6 dBi for different polarization modes. The proposed antenna has the advantages of multi-polarization reconfigurable ability, wide bandwidth, low profile, and high gains, which make it possible to be applied to wireless communication systems. |
| Author(s): | Q. Xu, Z. Liu, S. Liu, X. Kong, Z. Huang, B. Bian, Q. Yu, J. Qin |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 3 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1903 KB |
| Title: | Wideband High-Gain Fabry-Perot Resonator Antenna with Small Footprint Dielectric Superstrates and a Conical Short Horn |
| File Type: | Conference Paper |
| Issue: | Volume: 2-1-B Modeling, Optimization and Design of Antennas Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 421 KB |
| Title: | Wideband Hexagonal Fractal Antenna on Epoxy Reinforced Woven Glass Material |
| Abstract: | In this paper a novel hexagonal-circular Fractal antenna is proposed for wideband applications. The proposed antenna is made of iterations of a circular slot inside a hexagonal metallic patch with a transmission line and is fabricated on low cost epoxy matrix reinforced woven glass material. Measurement shows that with a dimension of 0.36?0×0.36?0×0.0071?0 (where ?0 is the lower edge frequency of the operating band), the proposed antenna achieves a wide impedance bandwidth ranging from 1.34 GHz to 3.44 GHz (88%). The proposed antenna also achieves high gain and exhibits a stable radiation pattern which makes it suitable for many wireless communications such as DCS-1800, PCS-1900, IMT-2000/UMTS, ISM (including WLAN), Wi-Fi and Bluetooth. |
| Author(s): | M. A. Dorostkar, R. Azim, M. T. Islam, Z. H. Firouzeh |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 6 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 902 KB |
| Title: | Wideband GCPW-Fed Dielectric Resonator Antenna for WLAN Applications |
| File Type: | Conference Paper |
| Issue: | Volume: S19 Broadband Antennas and Applications Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 412 KB |
| Title: | Wideband Filtering Crossover Based on Ring Resonator with Sharp Rejection |
| Abstract: | A wideband filtering crossover based on ring resonators with sharp rejection is proposed in this paper. Four transmission zeros near the crossover passband can be adjusted conveniently by the even/odd-mode characteristic impedance of the coupled lines. A high selectivity wideband filtering crossover located at 3.0 GHz is designed and fabricated for verification. Good filtering performance and high selectivity for the crossover are realized and experimentally verified. |
| Author(s): | W. Yang, W. Feng, W. Che |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 10 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 2101 KB |
| Title: | Wideband Fabry-Perot Cavity Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: 2-1-B Modeling, Optimization and Design of Antennas Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 350 KB |
| Title: | Wideband Equivalent Circuit Model and Parameter Computation of Automotive Ignition Coil Based on Finite Element Analysis |
| Abstract: | This paper presents a coupled fieldcircuit method to predict the wideband characteristic of ignition coils. A lumped circuit model is proposed, which separates the winding of ignition coil into individual sections. In this circuit model, the capacitance between sections, turn-toturn series capacitance of each single section and inductance of winding are calculated by Finite Element Analysis (FEA). This parameter identification is based on the energy principle. In addition, this paper analyzes the influence of frequency on the magnetic-flux distribution and the inductance, using the finite-element model with T- ? formulation. The parameter inductance applied to the circuit model is classified into high frequency inductance and low frequency inductance. Through contrasting the measured and calculated result in frequency and time domain, reliability and feasibility of the presented method in this paper is verified. |
| Author(s): | J. Jin, W. Quan-di, Y. Ji-hui, Z. Ya-li |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 7 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 1059 KB |
| Title: | Wideband Dual-polarized Vivaldi Antenna with Gain Enhancement |
| Abstract: | A wideband dual-polarized Vivaldi antenna covering 1.85-18.3 GHz band with enhanced gain is presented in this letter. The proposed antenna consists of two Vivaldi antenna elements (VAEs), which are designed based on the conventional Vivaldi antenna. Dual-slot structure is employed to improve the gain of the conventional Vivaldi antenna. As a result, sphericallike waves across the slot aperture of the conventional Vivaldi antenna can be transformed to be plane-like waves and thus gain enhancement can be achieved. In order to extend lower frequency limit of the VAE, elliptical slots are adopted. The proposed dual-polarized Vivaldi antenna is obtained by combining two VAEs in a cross-shaped form. The prototype is simulated, fabricated, and measured. A good agreement between EM simulated and measured results evidently validates the proposed antenna. |
| Author(s): | H. Lv, Q. Huang, J. Hou, J. Liu |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2769 KB |
| Title: | Wideband Dielectric Resonator Antenna with Parasitic Strip |
| File Type: | Conference Paper |
| Issue: | Volume: Dielectric Resonator Antennas Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 270 KB |
| Title: | Wideband Dielectric Resonator Antenna Excited by a Closed Circular Loop GCPW Slot for WLAN 5.5 GHz Applications |
| Abstract: | A dielectric resonator antenna is designed for WLAN 5.5 GHz band applications in this study. The dielectric resonator antenna is fabricated on a cheap FR4 substrate with grounded CPW (GCPW) structure. A new closed circular loop GCPW slot structure is employed to obtain wideband impedance matching. Results of the designed dielectric resonator antenna show that good agreement between simulated and measured reflection coefficients, radiations, and antenna gains is observed. The measured -10 dB bandwidth of the dielectric resonator antenna is 1.6 GHz (28.5%, 4.8 – 6.4 GHz), which covers the WLAN 5.5 GHz band. |
| Author(s): | W.-C. Weng, M.-C. Chang, M.-S. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 2 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1811 KB |
| Title: | Wideband Compact Antenna with Partially Radiating Coplanar Ground Plane |
| Abstract: | Many of today's portable communication applications require antennas that are compact, broadband, and easily integrable in a big variety of terminal geometries. This paper presents a compact wideband antenna with partially radiating coplanar ground plane. The prototype of the antenna shows a wide bandwidth (VSWR ? 2) of 92% (from 3.53GHz to 9.5GHz). The antenna also exhibits maximum gain of 3.5dBi and stable radiation patterns over the whole bandwidth. Nevertheless, in this paper the significance of the ground planes on the operating bandwidth are examined with the help of current distribution and discussed in detail with supporting parametric analysis. |
| Author(s): | A. T. Mobashsher, M. T. Islam, N. Misran |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 1 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 608 KB |
| Title: | Wideband Bow-Tie Slot Antennas with Tapered Tuning Stubs |
| File Type: | Conference Paper |
| Issue: | Volume: Advanced Computational Techniques for Antenna Design Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 113 KB |
| Title: | Wideband and High Gain Shared-Aperture Fabry-Perot Resonator Microstrip Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: 2-P2-E Antennas with Advanced/Artificial Materials and Processes Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 386 KB |
| Title: | Wideband and Dual-Band Loaded Monopole Dielectric Resonator Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: Recent Antenna Applications Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 195 KB |
| Title: | Wide-Angle Claerbout Scheme for Three-Dimensional Time Domain Parabolic Equation and its CN, ADI, AGE Solutions |
| Abstract: | The wide-angle Claerbout scheme of three-dimensional time domain parabolic equation (Claerbout-TDPE) is derived in this paper, which can provide accurate results at angles within 25° of the paraxial direction. At first, the Crank-Nicolson (CN) type is introduced to discretize the Claerbout-TDPE. In this way, a three-dimensional EM scattering problem can be divided into a series of two-dimensional ones. Moreover, the alternating direction implicit (ADI) type is utilized to the Claerbout-TDPE. In this way, a three-dimensional EM scattering problem can be further reduced to a series of one-dimensional ones. Furthermore, the alternating group explicit (AGE) type is introduced to the Claerbout- TDPE for higher computational efficiency. Comparisons are made among the CN, ADI and AGE types in the numerical results. |
| Author(s): | Z. He, H.-C. Yin, R.-S. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 3 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1847 KB |
| Title: | Wide-Angle Absorbing Boundary Conditions for Low and High-Order FDTD Algorithms |
| Abstract: | Wide-angle performance of the perfectlymatched- layer absorbing boundary conditions for the finite-difference time-domain (FDTD) method is investigated for efficient modeling of electrically large structures. The original split-field, uniaxial and convolutional perfectly-matched-layer formulations are all optimized to produce near-flat absorption for incidence angles up to 87 degrees. Optimized wide-angle parameters are derived for both the standard FDTD method and a high-order finite-volumes-based variant. The investigated high-order algorithm in particular is shown to produce improved wide-angle performance over standard FDTD for all three perfectly-matched-layer variants even when they are optimized for normal wave incidence. In all cases, optimization is managed through appropriate choices of modeling parameters which can be directly and unobtrusively applied to existing FDTD codes. |
| Author(s): | Mohammed F. Hadi |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 1 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 113 KB |
| Title: | Wide Stop-Band Microstrip Lowpass Filter with Sharp Roll-off Using Hairpin Resonators |
| Abstract: | A compact microstrip lowpass filter with wide stop-band and sharp roll-off skirt is presented. The structure consists of a combination of modified Hairpin units. The cut-off frequency is 3.1 GHz. The proposed low-pass filter has a very good performance such as extended stop-band bandwidth from 3.36 GHz to 21.5 GHz with the insertion-loss higher than -20.0 dB, sharp roll-off, low insertion-loss, and high return-loss in the passband. The filter is designed, fabricated, and tested and the measured results are in good agreement with the EM-simulation results. |
| Author(s): | M. Hayati, H. S. Vaziri |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 10 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1113 KB |
| Title: | Wide Bandwidth Endfire Antenna with Log-Period Directors |
| Abstract: | This paper presents the design and implementation of a novel wide bandwidth endfire antenna with log-periodic directors. The feeding structure of the proposed antenna includes a balun which is formed using a pair of microstrip-to-slotline transitions. The proposed antenna has three resonant frequencies in the operating frequency band. Both simulation and measurement results show that the operating frequency band of the antenna for S11 < -10 dB covers the wide bandwidth (5 GHz – 10 GHz), and the relative bandwidth is 67%. Far field measurements in azimuth plane and elevation plane show that the radiation patterns are stable and end fire within the operating band at frequencies of 5 GHz, 7 GHz, 8 GHz, 10 GHz. The proposed antenna radiates a well-defined endfire beam, with a front-to-back ratio > 18 dB and cross polarization level below -28 dB. The dimension of the proposed antenna is 26 mm × 27 mm. Good return loss and radiation pattern characteristics are obtained and measured results are presented to validate the usefulness of the proposed antenna structure for wide bandwidth endfire applications. |
| Author(s): | Y. Sun, G. Wen, H. Jin, P. Wang, Y. Huang, J. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 11 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 957 KB |
| Title: | Wide Band Wide Scanning Angle Phased Array Antenna Design in Ku-band |
| File Type: | Conference Paper |
| Issue: | Volume: 1-P1-C Wideband and Multiband Antennas Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 242 KB |
| Title: | Wide Band Implantable Antenna Operating at MedRadio Band for MBAN Devices |
| File Type: | Conference Paper |
| Issue: | Volume: 1-4-D EM, Antennas and Wireless Power for Biomedical Applications Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 295 KB |
| Title: | Wide Band Flexible Terahertz Metasurface Wave Plate |
| File Type: | Conference Paper |
| Issue: | Volume: 1-SP-4 Metasurfaces/Metamaterials Theory, Design and Applications I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 388 KB |
| Title: | Wide Band Antenna with Ultra-smooth Spectral Characteristics |
| File Type: | Conference Paper |
| Issue: | Volume: S09 Advances in Electromagnetic Modeling by WIPL-D - I Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 389 KB |
| Title: | Wide Band Antenna with Ultra-smooth Spectral Characteristics |
| Abstract: | Understanding the evolution of Universe is, in the forefront of, the modern day observational cosmology. It requires precise and accurate measurement of cosmological signal, orders of magnitude weaker than the bright sky background. Detection of such a signal having distinct spectral signature, needs an antenna with frequency independent characteristics over more than an octave bandwidth. A spherical monopole antenna has been designed to operate in the frequency range 50-200 MHz with a spectral smoothness of about few parts in 104. The structure has been modeled and optimized using WIPL-D, to minimize spectral features arising out of abrupt reflections of surface currents and frequency dependent radiation patterns. A prototype has been built to validate the design. This paper presents the methodology adopted in the overall antenna design, experiences in its prototyping and simulation and the measurement results. |
| Author(s): | A. Raghunathan, B. S. Girish, R. Somashekar, K. S. Srivani, S. Singh, R. Subrahmanyan, N. U. Shankar, M. S. Rao, J. Nambissan T. |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 11 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1331 KB |
| Title: | Why does SBVH outperform KD-tree on parallel platforms? |
| File Type: | Conference Paper |
| Issue: | Volume: S41 Parallel and GPU Computations Number: Year: 2016 |
| Download Link: | Login To Download (For Members) File Size: 191 KB |
| Title: | Whistler Mode Wave Refractive Index in a Finite Temperature Anisotropic Plasma Medium |
| Abstract: | Whistler mode waves, which exist in a magnetized plasma, are prevalent in the Earth's magnetosphere in the extremely low frequency (ELF) and very low frequency (VLF) bands (100 Hz - 30 kHz). Due to the impact of whistler mode waves on space weather processes, it is important to accurately predict the propagation trajectory of these waves and their properties. Numerical raytracing determines the power flow path of the whistler mode waves in the anisotropic medium of the magnetosphere based on local calculation of the refractive index. In the majority of previous work, magnetospheric raytracing has been implemented assuming a cold background plasma (0 K). However, a more accurate description of the magnetospheric plasma includes a background temperature of about 1 eV (11600 K). We present solutions to the dispersion relation that include the effects of finite electron and ion temperatures on the wave refractive index using a warm plasma formulation. Finite temperature effects of the background plasma are shown to be most significant for highly oblique wave normal angles where the refractive index is bounded to smaller values than in the ideal cold plasma approximation. |
| Author(s): | M. Golkowski, A. Maxworth |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 10 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1848 KB |
| Title: | Whistler Mode Wave Numerical Raytracing in a Finite Temperature Anisotropic Plasma Medium |
| File Type: | Conference Paper |
| Issue: | Volume: S39 Modeling Electromagnetic Waves in Plasma Environments Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 273 KB |
| Title: | Whispering Gallery Mode Laser in an Elliptical Microring |
| Abstract: | Studies on whispering gallery mode (WGM) laser in microrings have been limited to circular geometry. Elliptical microring lasers, despite their potential engineering use, have not been analyzed to guide experiments. This paper introduces a computationally efficient method for determining the WGM laser resonance and the laser field distribution in an elliptical microring. An analytical method is applied to avoid computing high order Mathieu functions. Both WGM resonant frequencies and electromagnetic (EM) field distributions are computed and presented in this paper. Computed results clearly show that the WGM laser field is concentrated on the outer surface of the microring. Results also show that the eccentricity of the ellipse affects the distribution of resonant frequencies and the laser field. |
| Author(s): | R. Baktur, L. W. Pearson, J. M. Ballato |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 2 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 419 KB |
| Title: | Where Intangibles Collide |
| File Type: | Newsletter Paper |
| Issue: | Volume: 20 Number: 2 Year: 2005 |
| Download Link: | Click here to download PDF File Size: 214 KB |
| Title: | Where does the radiation come from? |
| File Type: | Conference Paper |
| Issue: | Volume: Poster Session 1 Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 89 KB |
| Title: | What Do You Mean By a Solution to an Operator Equation? |
| Abstract: | The main thrust of this presentation is to illustrate that for many electromagnetic field problems the quality of the solution is very subjective and not objective at all. Therefore to classify solutions on a subjective criteria which is not scientific will create more problems than it would solve. The underlying feature to all this is what do "we mean" by a solution. |
| Author(s): | T.K. Sarkar, E. Arvas, T.K. Sarkar, E. Arvas |
| File Type: | Journal Paper |
| Issue: | Volume: 4 Number: 3 Year: 1989 |
| Download Link: | Click here to download PDF File Size: 333 KB |
| Title: | Well-Conditioned CFIE for Scattering from Dielectric Coated Conducting Bodies above a Half-Space |
| Abstract: | In this paper, a well-conditioned coupled combined-field integral equation called the electric and magnetic current combined-field integral equation (JCFIE-JMCFIE) is proposed for the analysis of electromagnetic scattering from coated targets above a lossy half-space. The halfspace multilevel fast multipole algorithm (MLFMA) is used to reduce computational complexity. The inner-outer flexible generalized minimal residual method (FGMRES) was used as the iterative solver to further speed up the convergence rate. Numerical results were presented to demonstrate the accuracy and efficiency of the proposed method. |
| Author(s): | D. Ding, J. Ge, R. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 11 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 401 KB |
| Title: | Well-Conditioned 2D Models of Rod Arrays for Accelerating 3D Simulations of Photonic Crystals and Plasmonic Structures |
| File Type: | Conference Paper |
| Issue: | Volume: S06 Advanced Methods for Numerical Electromagnetic Analysis - I Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 1009 KB |
| Title: | Wearable Textile Fabric Based 3D Metamaterials Absorber in X-Band |
| Abstract: | In this paper, a new wearable (flexible) textile fabric-based 3D metamaterials absorber (MMA) structure is proposed. The proposed MMA was created from three layers; weft-knitted fabric, silicone, and plain weave fabric and then, it was simulated in Computer Simulation Technology (CST). It was obtained maximum absorption power (99.66%) at 9.38 GHz, and the average absorption power of 81-95% was obtained in the frequency range of 8 to 12 GHz depending on the incident angle in the simulation. The effect of the wearable textile structure on absorption was investigated. When compared with other materials, it can be said that the proposed MMA is broadband, incident angle independent, TE and TM polarization-independent, flexible, breathable, wearable, ease of fabrication, practical, low weight, and cost advantage. With this designed the textile fabric-based MMA, it can be obtained both low reflection coefficients and low transmission coefficients at broadband X-band frequencies. This provides a good solution for the cloaking of radar systems. |
| Author(s): | E. Delihasanlar, A. H. Yuzer |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 2 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1722 KB |
| Title: | Wearable Radar Antenna Array Design on Flexible PCB for Visually Impaired People |
| File Type: | Conference Paper |
| Issue: | Volume: S47 Advanced Antenna Designs for Emerging Wireless Applications Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 304 KB |
| Title: | Wearable Panda-Shaped Textile Antenna with Annular Ring-Defected Ground Structure for Wireless Body Area Networks |
| Abstract: | This research presents a compact pandashaped wearable antenna with a defected ground structure (DGS). It is fabricated using a flexible material to work at 2.4-GHz industrial scientific medical (ISM) band, confirming the wireless body area network (WBAN) application requirements. The annular ring DGS and circular and elliptical slots in the patch aid in achieving the operating frequency. Good impedance bandwidth is maintained during on-body and bending analysis. Furthermore, this antenna exhibits a peak gain of 7.3 dB and a minimum specific absorption rate (SAR) of 0.0233 W/kg for 1 g tissue and 1.02 W/kg for 10 g tissue. The investigation shows that an antenna with good robustness, compact, high flexibility, and very low SAR makes it a strong candidate for WBAN applications. |
| Author(s): | T. Annalakshmi, S. Ramesh |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 5 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 3568 KB |
| Title: | Wearable Graphene Based Curved Patch Antenna for Medical Telemetry Applications |
| Abstract: | In order to explore the expediency of graphene for biotelemetry in Wireless Body Area Network (WBAN), conformal square patch antenna design has been presented in this paper. The operational efficiency of the antenna is attributed to the incredible properties of graphene as patch conductor. The proposed antenna designed for operating in band from 1-4.88 GHz is fed with microstrip line and quarter wave transformer for impedance matching. The antenna however achieves best performance at 2.4 GHz in ISM band with good impedance matching, reasonable dB gain and high radiation efficiency for the wideband of frequencies in GHz range. The proposed wearable conformal graphene based antenna is optimally positioned at distance from body to make it suitable for Ultra Wide Band (UWB) health monitoring systems fulfilling the requirements of wideband operation, high gain and improved radiation efficiency at reduced SAR. |
| Author(s): | R. Bala, R. Singh, A. Marwaha, S. Marwaha |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 798 KB |
| Title: | Wearable Antennas for Body-Centric Communications: Design and Characterization Aspects |
| Abstract: | Wearable antennas exhibit numerous challenges in terms of design and optimization due to the specific environment in which they operate. Therefore, the design of such antennas is a non-trivial task, as multiple constraints have to be satisfied. We present an algorithm for design-and-optimization of flexible wearable antennas with high radiation efficiency and low specific absorption rate, that takes into account the dielectric loading of the human body. It provides a list of feasible antenna designs, not just a single solution, and identifies the optimal wearable antenna design. Numerical examples on the design and optimization of a wearable antenna (based on a dipole structure with a reflector) to demonstrate the validity and efficiency of the proposed algorithm are given. The optimal antenna design shows robust on-body performance and provides a suitable balance between small antenna size (antenna surface is 2214 mm2), high radiation efficiency (57.73%), and low value of the maximum 10 g average SAR (0.112 W/kg) on a homogeneous semisolid phantom. Finally, the optimal antenna design is fabricated. The antenna performance is studied under different conditions: on a homogeneous semisolid phantom, on a liquid phantom, on a three-layer semisolid phantom, on a human arm and in the free space. A good agreement between simulated and measured antenna performance is observed. |
| Author(s): | A. G. Al-Sehemi, A. A. Al-Ghamdi, N. T. Dishovsky, N. T. Atanasov, G. L. Atanasova |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 8 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1835 KB |
| Title: | Wearable and implantable RFIDs for Human-body Sensing |
| File Type: | Conference Paper |
| Issue: | Volume: RFIday 2010 Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 149 KB |
| Title: | Ways to Improve Computational Efficiency of GRE |
| File Type: | Conference Paper |
| Issue: | Volume: High Frequency Techniques Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 437 KB |
| Title: | Waveport Modeling for DGTD Method and Its Applications |
| File Type: | Conference Paper |
| Issue: | Volume: 2-SE-3 Advances in Electromagnetic Theory and Simulation Techniques II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 7 KB |
| Title: | Wavelet Packet Transform with Iterative Technique based on Method of Moments |
| File Type: | Conference Paper |
| Issue: | Volume: MoM and Applications Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 211 KB |
| Title: | Wavelet Packet Transform of the Method of Moments Matrix for Large-Scale Problems |
| File Type: | Conference Paper |
| Issue: | Volume: MoM and Applications Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 191 KB |
| Title: | Wavelet Model of Multivariate Prior Covariance |
| File Type: | Conference Paper |
| Issue: | Volume: S59 Uncertainty Quantification and Modeling for Complex Applications Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 397 KB |
| Title: | Wavelet Analysis of Permanent Magnet Synchronous Machine Flux Density Harmonic Content With Different Pole Number Designs |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in CEM Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 372 KB |
| Title: | Waveguides with Hyperbolic Metasurface Claddings |
| File Type: | Conference Paper |
| Issue: | Volume: Student Paper Competition Number: Year: 2014 |
| Download Link: | Login To Download (For Members) File Size: 588 KB |
| Title: | Waveguides with Hyperbolic Metasurface Claddings |
| File Type: | Conference Paper |
| Issue: | Volume: Computational Methods in Nanoelectromagnetics Number: Year: 2014 |
| Download Link: | Login To Download (For Members) File Size: 588 KB |
| Title: | Waveguides with Exceptional Points of Degeneracy of Order 2, 3, 4 and 6 without Loss and Gain |
| File Type: | Conference Paper |
| Issue: | Volume: S33 Complex Meta-Structures and Applications - II Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 1967 KB |
| Title: | Waveguide Mode Computation through Smoothed Particle Electromagnetics |
| File Type: | Conference Paper |
| Issue: | Volume: Modeling, Design and Optimization of Complex Electromagnetic Systems Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 160 KB |
| Title: | Waveguide Microwave Imaging: Solids Volume Fraction of Particulate Materials |
| Abstract: | An original modeling-based microwave imaging technique for determining the volume fraction of solid material in dielectric powders is described. The desired characteristic is determined by analyzing S-parameter measurements in a waveguide containing the sample with the help of an artificial neural network trained by data from 3D FDTD simulation. The powder sample is represented by a mixture of air and millimeter-scale particles reproduced in the FDTD model. Computational tests with 20 to 40 mm cubic samples of SiC and ZrO2 powders in WR340 show that the solids volume fraction is determined with less than 5% error. |
| Author(s): | A. V. Brovko, E. K. Murphy, V. V. Yakovlev |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 11 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 2551 KB |
| Title: | Waveguide Filter Modeling and Simulation using Mode-matching, Fullwave Network Analysis and Swarm Optimization |
| Abstract: | This paper presents the modeling of waveguide bandpass filter synthesis. It consists of a combination of the most appropriate and reliable methods and techniques of analysis, simulation and optimization used in determined order and leading to a fast and accurate method of filter synthesis. An example of a forth-order filter synthesis is given, employing a symmetric configuration and symmetric response. The obtained results, reference measurement and commercial software simulator results are compared for validation. |
| Author(s): | I. Bouchachi, J. Mateu, M. L. Riabi |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 2 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1964 KB |
| Title: | Wavefront Reconstruction Using a Dispersive Propagation Model |
| File Type: | Conference Paper |
| Issue: | Volume: Inverse Scattering in Medicine and Biology - State of the Art, Recent Advances and Future Trends Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 146 KB |
| Title: | Waveform of Class E Power Amplifiers with PI Network |
| File Type: | Conference Paper |
| Issue: | Volume: 4-1-C Passive/Active Microwave and Terahertz Devices Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 242 KB |
| Title: | Wave Propagation on Two Dimensional Doubly-Periodic Guiding Structures. |
| File Type: | Conference Paper |
| Issue: | Volume: Computer Simulation of Electromagnetic-System Testing Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 168 KB |
| Title: | Wave Propagation on a Circular Chiral Rod |
| File Type: | Conference Paper |
| Issue: | Volume: Guided Waves in Non-Standard Media Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 84 KB |
| Title: | Wave Propagation and Radio Network Planning Software WinProp added to the Electromagnetic Solver Package FEKO |
| File Type: | Conference Paper |
| Issue: | Volume: S19 Modeling with FEKO Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 972 KB |
| Title: | Wave Propagation Along a Thin Vertical Wire Antenna Placed in a Horizontally Layered Medium |
| File Type: | Conference Paper |
| Issue: | Volume: Fundamental Electromagnetics: Materials and Boundaries Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 261 KB |
| Title: | Wave Concept Iterative Process Merges with Modal Fast Fourier Transformation to Analyze Microstrip Filters. |
| Abstract: | A novel iterative method based on the concept of waves is reported for use in the field theory, computer aided design and optimization of high frequency integrated circuits. It consists of a recursive relationship between a given source and reflected waves from the discontinuity plane which is divided into cells. A high computational speed has been achieved by using Modal Fast Fourier Transformation (MFFT). The theory as well as its procedure implementation is described. Numerical results are succussfully compared with published data. |
| Author(s): | A. Gharsallah, R. Garcia, A. Gharbi, H. Baudrand, A. Gharsallah, R. Garcia, A. Gharbi, H. Baudrand |
| File Type: | Journal Paper |
| Issue: | Volume: 16 Number: 1 Year: 2001 |
| Download Link: | Click here to download PDF File Size: 459 KB |
| Title: | Wave Concept in MoM-GEC Formalism |
| File Type: | Conference Paper |
| Issue: | Volume: S34 Computational Electromagnetics Advanced Algorithms and Emerging Applications IV Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 173 KB |
| Title: | Wave Characteristics Of Layered Anisotropic Media for Remote Sensing Applications |
| File Type: | Conference Paper |
| Issue: | Volume: S49 EM Modeling and Applications - II Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 169 KB |
| Title: | Water-based Metamaterial Absorber for Broadband Electromagnetic Wave Absorption |
| File Type: | Conference Paper |
| Issue: | Volume: 2-1-C Properties, Modelling and Novel Concepts of Artificial Electromagnetic Structures I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 521 KB |
| Title: | Water Extraction of SAR Image Based on Region Merging Algorithm |
| File Type: | Conference Paper |
| Issue: | Volume: 2-1-E Synthetic Aperture Radar Techniques and Applications I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 314 KB |
| Title: | Water Content and Tissue Composition Effects on Microwave Tomography Results |
| File Type: | Conference Paper |
| Issue: | Volume: Microwave Imaging and Inverse Problems Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 310 KB |
| Title: | Waffle Iron Filter Design using WIPL-D |
| File Type: | Conference Paper |
| Issue: | Volume: S20 Advances in Electromagnetic Modeling by WIPL-D - II Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 914 KB |
| Title: | W-Band Longitudinal-Slot Coupling Four-Way SIW Power Combiner/Divider |
| File Type: | Conference Paper |
| Issue: | Volume: 3-P3-H Passive/Active Microwave and Terahertz Devices Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 352 KB |
| Title: | W-band High-Gain Antenna Arrays with Low-Loss Gap Waveguide Feeding Network |
| File Type: | Conference Paper |
| Issue: | Volume: 2-1-B Modeling, Optimization and Design of Antennas Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 832 KB |
| Title: | W-band Electronic Focus-Scanning by a Reconfigurable Transmitarray for Millimeter-Wave Imaging Applications |
| Abstract: | A w-band electronic focus-scanning function, which is desired for high-resolution fast-speed millimeterwave imaging systems, is realized by a reconfigurable transmitarray antenna (RTA). As a two-layer structure, each RTA element is integrated with two packaged PIN diodes symmetrically within a limited area (1.6×1.6mm2). When a linearly polarized electromagnetic wave incidents on this reconfigurable element, an orthogonally polarized transmission wave is generated, with the ability of 1-bit phase adjustment (0°/180°). Using this element, a 32×2 reconfigurable transmitarray is designed and fabricated to realize 1-D steerable focal points in a near-distance focal plane. The measured focal points agree well with the design, illustrating the feasibility of the proposed RTA for w-band microwave imaging systems. |
| Author(s): | X. Pan, F. Yang, S. Xu, M. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 5 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 21801 KB |
| Title: | Voxel-Based Inverse Methods |
| File Type: | Conference Paper |
| Issue: | Volume: Nondestructive Evaluation and Materials Characterization Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 97 KB |
| Title: | Vortex Beam Optimization Design of Concentric Uniform Circular Array Antenna with Improved Array Factor |
| Abstract: | In this paper, an improved array factor of the concentric uniform circular array (CUCA) antenna is proposed for the orbital angular momentum (OAM) vortex beam optimization design. From the perspective of the radiation pattern’s power conservation principle, a correction factor is introduced to the conventional array factor of CUCA. Then, based on the improved array factor, by adjusting the rings’ radii parameters of the CUCA, we optimize the vortex beam’s sidelobe level through the generic algorithm (GA). Two different CUCA antenna model are calculated as examples to further illustrate the effectiveness of the improved array factor. Subsequently, an electromagnetic simulation model of two rings CUCA antenna is built at C band for generating low sidelobe vortex beam carrying OAM mode. The electromagnetic simulation model of the designed CUCA antenna is also fabricated and measured. The corresponding antenna far-field vortex beam radiation pattern and near-field vortex wave electric field distributions are measured. The simulation results and the measurement results are in good agreement. The proposed designs of antenna and OAM vortex beam regulation are expected to be used for 5G and 6G communications applications. |
| Author(s): | Q. Feng, Y. Lin, Y. Zheng, L. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 7 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1726 KB |
| Title: | VOLUME LOADING -- A NEW PRICIPLE FOR SMALL ANTENNAS |
| Abstract: | Volume loading means placing conductively enclosed volumes at the ends of the arms of a short linear antenna to increase and control the capacitance of the structure. This technique allows tuning the antenna to make it series-resonant at a design frequency for which it is electrically small. This paper describes the discovery and development of the concept, gives some computed examples to illustrate the relation between shape and performance, and describes some experimental work, including a 900 MHx corless phone demonstration design. |
| Author(s): | D.B. Miron, D.B. Miron |
| File Type: | Journal Paper |
| Issue: | Volume: 14 Number: 2 Year: 1999 |
| Download Link: | Click here to download PDF File Size: 662 KB |
| Title: | Voltage Parameter Identification of AC Overhead Transmission Lines by Using Measured Electric Field Data |
| Abstract: | With the development of smart power grids, the demand for real-time voltage monitoring along overhead transmission lines (OTLs) has been growing. However, the existing voltage measurement of OTLs by using potential transformers involves formidable difficulties. This study proposes a non-contact measurement method in which the voltages on AC OTLs are inversely calculated on the basis of the measured data of the power frequency electric field under OTLs. To improve the accuracy and stability of the inverse calculation, an accurate mathematical model and modified inverse algorithms are investigated and then a set of feasible approaches are proposed. First, considering an overhead conductor’s actual physical form and the meteorological conditions of its operating environment, a 3-D catenary model is built, and the mathematical relations between 3-D electric fields and the voltages on OTLs are identified. Second, the improved particle swarm algorithm is used to search the optimal measurement positions of the electric field to improve the ill-posedness of inverse problems. Third, the iterative Tikhonov regularization method, in which the number of iterations is considered as the variable, is adopted to further improve the ill-posedness of inverse problems and reduce the susceptibility of regular solutions to regularization parameter alpha. Fourth, root mean square values and phase parameters of AC voltages are identified from the sinusoidal fitting curves obtained by the real-time inverse calculation. Results of the simulation and experiment examples show that inverse solutions of high precision can be obtained under the condition with relatively high errors of electric field measurement. Moreover, the advantages of the proposed inversion method, such as fast computing speed and good stability, are demonstrated. |
| Author(s): | D. Xiao, Q. Zheng, Y. Xie, Q. Ma, Z. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1840 KB |
| Title: | Voltage and Current Analysis for Arcing Detection on AC Overhead Electrified Railways |
| File Type: | Conference Paper |
| Issue: | Volume: Numerical Techniques for Electromagnetic Applications Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 135 KB |
| Title: | Vivaldi Antenna for GPR |
| File Type: | Conference Paper |
| Issue: | Volume: Novel Antennas Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 156 KB |
| Title: | Visualizing Time-Domain Distributed Electromagnetic Fields Using Sonnet |
| File Type: | Conference Paper |
| Issue: | Volume: EM Applications in Sonnet Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 755 KB |
| Title: | Visualization of Electric Field Amplitudes inside Porous Spherical Cavity Resonators |
| File Type: | Conference Paper |
| Issue: | Volume: EM Applications using WIPL-D Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 1752 KB |
| Title: | Virtual Source Modeling of the High-Frequency Scattering of the Infinite Conducting Strip under Cylindrical Wave Excitation |
| File Type: | Conference Paper |
| Issue: | Volume: Macromodeling for EMC and SI Complex Systems Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 136 KB |
| Title: | Virtual Design of Insulation Elements Based on FEM and Automated Optimization Process |
| File Type: | Conference Paper |
| Issue: | Volume: Hybrid CEM Techniques Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 201 KB |
| Title: | Vibration Isolation of Magnetic Suspended Platform with Double Closed-loop PID Control |
| Abstract: | In magnetic vibration isolation field, magnetic force is used for the isolation, while the whole isolation system is always supported passively, which have non-control shortcomings. Aimed at this problem, a novel active control strategy with a double closed-loop PID algorithm was designed in this paper. The double closed-loop strategy includes an internal and external loop control, which was designed to fulfill the magnetic levitation and isolation, respectively. Firstly, the vibration isolation strategy proposed in this paper was simulated in both time and frequency domain. The simulation results showed that this method possesses good performance of vibration isolation. Then, an active levitation and vibration isolation control experiment was designed. The experimental results showed that the control algorithm has a good vibration control effect under periodic vibration and random vibration conditions. |
| Author(s): | M. Tang, J. Zhou, C. Jin, Y. Xu |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 8 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 2261 KB |
| Title: | Via Modeling in Multi-Gbits/s Signal Analysis |
| File Type: | Conference Paper |
| Issue: | Volume: Black Box Modeling Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 334 KB |
| Title: | VHF-UHF Monocone Antenna for Ground Penetrating Radar Application |
| Abstract: | This paper introduces a VHF-UHF monocone antenna for ground penetrating radar GPR application. The proposed antenna covers different bandwidths through only changing the cone geometry. Same ground plane shape and feeding system are used. Firstly, both conventional and proposed monocone antennas are designed, simulated and their simulated results are compared. One antenna cone is fabricated and measured for verification purpose. Good agreement is obtained between measured and simulated bandwidths. The measured bandwidth extends from 73 MHz to 500 MHz. Secondly, another antenna cone is designed and simulated without altering the upper or the lower cone radii. The second cone antenna bandwidth extends from 130 MHz to 1000 MHz. The receiver antenna of the commercial SIR 2000 impulse GPR is replaced by the proposed VHF-UHF first monocone antenna and the field test results are recorded and discussed. |
| Author(s): | T. G. Abouelnaga, E. A. Abdallah |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 5 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1931 KB |
| Title: | VHF Antennas on Unmanned Air Vehicles (UAV) for a Simplified Synthetic Aperture Radar (SAR) |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Simulation using FEKO Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 506 KB |
| Title: | VHF Antenna Modeling for Rocket Application |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Modeling using FEKO – I Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 182 KB |
| Title: | VFD Approach to the Computation TE and TM Modes in Elliptic Waveguide on TM Grid |
| File Type: | Conference Paper |
| Issue: | Volume: Finite Difference Methods Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 351 KB |
| Title: | VFD Approach to the Computation TE and TM Modes in Elliptic Waveguide on TM Grid |
| Abstract: | We describe here a vector finite difference approach (VFD) to the evaluation of eigenvalues and modes of elliptical waveguides. The FD is applied using a 2D elliptical grid in the waveguide section. A suitable Taylor expansion of the vector mode function allows to take exactly into account the boundary condition. To prevent the raising of spurious modes, our FD approximation results in a constrained eigenvalue problem, that we solve using a decomposition method. This approach has been evaluated comparing our results to known data for the elliptic case. |
| Author(s): | A. Fanti, G. Montisci, G. Mazzarella, G. A. Casula |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 12 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 515 KB |
| Title: | Versatile Nanoparticle Manipulation with Designer Thermoplasmonic Metasurface |
| File Type: | Conference Paper |
| Issue: | Volume: S48 Computational Nanophotonics: Advanced Numerical Methods and Applications II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 1011 KB |
| Title: | Verifying Received Power Predictions of Wireless InSite Software in Indoor Environments at WLAN Frequencies |
| Abstract: | This paper introduces a study on verifying received power at WLAN frequencies in indoor environments, Wireless InSite is a popular electromagnetic ray-tracing software which is widely used for predicting channel behaviour in indoor and outdoor environments. The study compares software-generated data with measurements collected through 3rd floor Chesham Building, University of Bradford, at WLAN frequencies, the paper also investigates the effect of changing settings on results accuracy and computational time, and finally, the paper presents a comparison between simulation results with empirical models. |
| Author(s): | H. A. Obeidat, O. A. Obeidat, M. F. Mosleh, A. A. Abdullah, R. A. Abd-Alhameed |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 10 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1903 KB |
| Title: | Verify Microstrip Antenna Using Feature Selective Verification Method |
| File Type: | Conference Paper |
| Issue: | Volume: 4-3-B Antenna Design and Optimization Techniques I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 463 KB |
| Title: | Verification Testing of Multi-Dynamical Solver for Multiferroic Antennas |
| File Type: | Conference Paper |
| Issue: | Volume: S42 Computational Methods Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 433 KB |
| Title: | Verification of the CADRCS RCS tool for NCTR work |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Modeling, Inversion and Applications Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 228 KB |
| Title: | VERIFICATION OF SOFTWARES FOR ELECTROMAGNETIC FIELD ANALYSIS USING MODELS PROPOSED BY INVESTIGATION COMMITTEES IN IEE OF JAPAN |
| Abstract: | In order to investigate methods for analyzing electromagnetic fields and to compare the accuracy and the CPU time of various codes and so on, investigation committees were set up in IEE of Japan. In this paper, the activities of various investigation committees relating electromagnetic field analysis are described from the viewpoint of the verification of software. [Vol. 12, No. 3 (1997), pp 50-61 |
| Author(s): | Norio Takahashi, Norio Takahashi |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 3 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 793 KB |
| Title: | Verification of Nonlinear Characteristics of Radar Angular Glint by Surrogate Data Method |
| Abstract: | In this paper, we present a nontrivial verification of nonlinear characteristics of angular glint by the surrogate data method. Glint is a key cause of target loss in radar detections. Prediction and suppression of glint is a hot topic. Firstly, glint data of a typical target are calculated by GRECO method for two motions. As glint is calculated by quadric surface calculations, it is nonlinear in mathematical nature. The surrogate data method is explained and workflow is summarized to verify the nonlinear traits of glint. Surrogate methods of phase randomized Fourier transform and amplitude adjusted Fourier transform are illustrated. Test statistics of higher order moments and time reversibility are given. Lorenz model is simulated as a standard nonlinear model to verify effectiveness of workflow, and nonlinear verification criteria are drawn. A new parameter is designed to measure the powerfulness of nonlinearity. Finally, nonlinear verifications for the two angular glint series are given. Results are illustrated in figures and data and they agree with nonlinear criterion. This paper lays the foundations for chaotic verifications of glint. |
| Author(s): | J. Zhang, Z. Li, C. zheng, J. Miao |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 10 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 997 KB |
| Title: | Vectorial GO and Diffraction Decomposition of Physical Optics Scattering of Dipole Wave from Planar Surfaces in Terms of Modified Edge Representation Line Integrals |
| File Type: | Conference Paper |
| Issue: | Volume: Asymptotic and High Frequency Techniques Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 467 KB |
| Title: | Vector Parabolic Equation Modeling of Wireless Propagation in Tunnels with Statistically Rough Surface Walls |
| File Type: | Conference Paper |
| Issue: | Volume: S59 Uncertainty Quantification and Modeling for Complex Applications Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 524 KB |
| Title: | Vector Parabolic Equation Modeling of Wireless Propagation in Tunnels with Statistically Rough Surface Walls |
| File Type: | Conference Paper |
| Issue: | Volume: S10 Student Paper Competition II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 524 KB |
| Title: | Vector Parabolic Equation Method for the EM Scattering from PEC Objects in Half-Space |
| Abstract: | The vector parabolic equation method was widely used to analyze the electromagnetic scattering from electrically large PEC objects in free space. In this paper, it is applied for the analysis of the electromagnetic scattering from PEC objects in halfspace. By introducing both the incident field and the reflected field to illuminate the objects, the vector parabolic equation method can be used to efficiently calculate the radar cross-section of PEC objects with electrically large size in half-space. The numerical results demonstrate that the proposed method can efficiently give reasonably accurate results. |
| Author(s): | Z. He, T. Su, R. S. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 8 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 1155 KB |
| Title: | Vector Control of PMSM Take Over by Photovoltaic Source |
| Abstract: | This article established with the modeling and the field oriented control of permanent magnet synchronous machines, with a focus on their applications in variable speed domain in photovoltaic source. |
| Author(s): | T. Yuvaraja, K. Ramya |
| File Type: | Express Journal Paper |
| Issue: | Volume: 1 Number: 6 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2266 KB |
| Title: | Vector Control of PMSM Take Over by Photovoltaic Source |
| Abstract: | This article established with the modeling and the field oriented control of permanent magnet synchronous machines, with a focus on their applications in variable speed domain in photovoltaic source. |
| Author(s): | T. Yuvaraja, K. Ramya |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 2 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1641 KB |
| Title: | Vector Control of PMSM Take Over by Photovoltaic Source |
| Abstract: | This article established with the modeling and the field oriented control of permanent magnet synchronous machines, with a focus on their applications in variable speed domain in photovoltaic source. |
| Author(s): | T. Yuvaraja, K. Ramya |
| File Type: | Express Journal Paper |
| Issue: | Volume: 33 Number: 2 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1641 KB |
| Title: | VARIOUS APPROACHES TO TORQUE CALCULATIONS BY FEM AND BEM |
| Abstract: | Different algorithms for the torque calculation by Maxwell stress method (MSM) are dealt with in the paper. The aim of designing these algorithms was to reduce the influence of the choice of the integration path and discretization of the air gap between the stator and rotor on the accuracy of the results. In some of these algorithms the connection between the stator and rotor is released For the magnetic field calculation the finite element method (FEM), boundary element method (BEM), and hybrid finite element - boundary element method (HM) were used. The calculation results were tested on a permanent magnet DC motor and a single phase brushless motor. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 127-130] |
| Author(s): | Mladen Trlep, Anton Hamler, Bozidar Hribernik, Mladen Trlep, Anton Hamler, Bozidar Hribernik |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 321 KB |
| Title: | Variational Analysis of Substrate-Integrated Waveguides with Longitudinal Slot |
| File Type: | Conference Paper |
| Issue: | Volume: S43 Advanced Applications I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 290 KB |
| Title: | Variable Phase-Shifter/Down Converter for Active Microstrip Phased Array Antenna Applications |
| File Type: | Conference Paper |
| Issue: | Volume: Poster Sessions 1 Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 1063 KB |
| Title: | Validity of Approximate Boundary Conditions in Analysis of Strip-Loaded Planar and Curved Surfaces |
| File Type: | Conference Paper |
| Issue: | Volume: Poster Sessions 1 Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 286 KB |
| Title: | Validation, Verification and Calibration in Applied Computational Electromagnetics |
| Abstract: | Model validation, data verification, and code calibration (VV&C) in applied computational electromagnetics is discussed. The step by step VV&C procedure is given systematically through canonical scenarios and examples. Propagation over flat-Earth with linearly decreasing vertical refractivity profile, having an analytical exact solution, is taken into account as the real-life problem. The parabolic wave equation (PWE) is considered as the mathematical model. MatLab-based numerical simulators for both the split step Fourier and finite element implementations of the PWE are developed. The simulators are calibrated against analytical exact and high frequency asymptotic solutions. Problems related to the generation of reference data during accurate numerical computations are presented. |
| Author(s): | G. Apaydin, L. Sevgi |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 12 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 1225 KB |
| Title: | Validation, Verification and Calibration in Applied Computational Electromagnetics |
| File Type: | Conference Paper |
| Issue: | Volume: CEM for EM Education Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 755 KB |
| Title: | VALIDATION OF, AND LIMITATIONS ON, THE USE OF NEC-4 FOR RADIATION FROM ANTENNAS BURIED WITHIN A HOMOGENEOUS HALF-SPACE |
| Abstract: | The use of the computer program NEC-4 for the simulation of radiation from buried antennas is considered. NEC-4 uses the “exact” Sommerfield integral formulation for stratified media (in NEC-4, re-stricted to an homogeneous half-space). Although the formulation is rigorous, certain approximations have to be made for numerical implementation. The formu-lation, and some of these issues, is outlined in the paper. Several validation examples comparing results computed using NEC-4 and results available in the lit-erature are presented for antennas buried in various typical media, including ground, fresh water, and the sea. Satisfactory agreement has generally been obtained; where differences have been noted, we have able to explain most in terms of approximate implementa-tion issues. |
| Author(s): | David B. Davidson, H. du Toit Mouton, David B. Davidson, H. du Toit Mouton |
| File Type: | Journal Paper |
| Issue: | Volume: 13 Number: 3 Year: 1998 |
| Download Link: | Click here to download PDF File Size: 554 KB |
| Title: | Validation of Wind Turbine Doppler Signatures in a Passive Bistatic Radar with a Point Scatterer Model |
| File Type: | Conference Paper |
| Issue: | Volume: S06 Advanced Radar Technologies and Techniques I Number: Year: 2019 |
| Download Link: | Login To Download (For Members) File Size: 961 KB |
| Title: | VALIDATION OF THE NUMERICAL ELECTROMAGNETICS CODE (NEC) FOR ANTENNA WIRE ELEMENTS IN PROXIMITY TO EARTH |
| Abstract: | This paper summarizes recent MITRE efforts to validate the NEC-3 and NEC-GS versions of the Numerical Electromagnetics Code (NEC) developed by Lawrence Livermore National Laboratory for predicting the performance of antenna wire elements in close proximity to flat earth. In an early version (NEC-l), the effect of the air-ground interface was included by applying a plane-wave Fresnel rei:lection coefficient approximation to the field of a point source. The NEC-2 version, while still retaining the Fresnel reflection coefficient model as an option, provides a more accurate ground model by numerically evaluating Sommerfeld integrals. The version NEC-3 extends the NEC-2 version to cases for bare wire segments below the air-earth interface. Version NEC-GS utilizes rotational symmetry to provide a more efficient version of NEC-3 for the case of a monopole element with a uniform radial wire ground-screen (GS). Results of the various versions are compared with each other and with other mndels. The input-output format of the NEC-GS version is discussed. It is concluded that the NEC-3 Sommerfeld integral option in the NEC-GS version is the best available model for monopole elements with electrically small radial-wire ground planes. [Vol. 8, No. 2 (1993), pp 44-71] |
| Author(s): | M. M. Weiner, M. M. Weiner |
| File Type: | Journal Paper |
| Issue: | Volume: 8 Number: 2 Year: 1993 |
| Download Link: | Click here to download PDF File Size: 1395 KB |
| Title: | VALIDATION OF THE MININEC3 CODE FOR COMPLEX RADIATING STRUCTURES |
| Abstract: | The ability of the MININEC3 code to accurately model complex radiating structures was previously unknown because computer compiler constraints limited the size of analyzable configuration. With the conversion of the code from BASIC to FORTRAN however it is now feasible to use it to simulate such structures. This paper presents the results of a validation exercise aimed at assessing the code's suitability for modelling configurations which involve hundreds of segments. [Vol. 9, No. 1 (1994), pp 58-66] |
| Author(s): | K.P. Murray, B.A. Austin, K.P. Murray, B.A. Austin |
| File Type: | Journal Paper |
| Issue: | Volume: 9 Number: 1 Year: 1994 |
| Download Link: | Click here to download PDF File Size: 771 KB |
| Title: | Validation of Fast Site-Specific Mean-Value Models for Indoor Propagation |
| Abstract: | A fast assessment of the local mean value of the electric field strength throughout a floor plan is useful for the design of local-area networks. Site-specific models require coding the location of walls, doorways, and other features and modelling their structure and electrical properties. Using ray tracing to find the field strength throughout the floor plan is slow and expensive because a grid of closely-spaced points is needed to trace the rapid variations called fast fading; then the raytracing local area average is found by explicit spatial averaging, to obtain the slow fading behavior. The raytracing mean value is obtained by combining the amplitudes of the fields associated with the rays on an energy basis; widely-spaced grid points can be used because the local mean value varies slowly with position, making the calculation fast and inexpensive. The Sabine method provides a energy-balance approach for an inexpensive estimate of the local mean value field strength. This paper tests the accuracy of the fast methods (the ray-tracing mean value and the Sabine mean value) against the local area average found from dense ray tracing, and against measurements. In a 40 m2 room of roughly square floor plan, the fields from the fast methods were close to those of dense ray tracing and to the measurements. But it is shown that in a long corridor, the ray-tracing mean value and the Sabine mean value were low compared to dense ray tracing, and so these fast methods should be used with caution. |
| Author(s): | C. W. Trueman, D. Davis, B. Segal, W. Muneer |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 3 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 264 KB |
| Title: | Validation of a Z-Matrix Finite Element Program for Analyzing Electrostatic Fields |
| Abstract: | Modern electrical equipment designs demand more compact, complex geometries and require more strigent analyses of the associated three-dimensional electrostatic fields. Analytical solutions of such fields are limited to relatively simple geometries. Numerical solutions using the finite element method are limited by available computer storage and processing time. Lauber posed an economical method for solving three-dimensional finite element electrostatic fields by forming the finite element system matrix using Brown's Z-matrix techniques. (Lauber, 1982) (Brown, 1975) This method was implemented by a FORTRAN computer program. (Barber and Lauber, 1986) (Barber, 1988) The purpose of this paper is to briefly describe the present version of the program called FEWZ (Finite Elements using a Windown and the Z-matrix) and to show how it was validated. |
| Author(s): | P.F. Barber, T.S. Lauber, E.D. Patterson, P.F. Barber, T.S. Lauber, E.D. Patterson |
| File Type: | Journal Paper |
| Issue: | Volume: 4 Number: 3 Year: 1989 |
| Download Link: | Click here to download PDF File Size: 945 KB |
| Title: | VALIDATION AND DEMONSTRATION OF FREQUENCY APPROXIMATION METHODS FOR MODELING DISPERSIVE MEDIA IN FDTD |
| Abstract: | Recently, digital signal processing techniques were used to design, analyze and implement discrete models of polarization dispersion for the Finite-Difference Time-Domain (FDTD) method. The goals of the present work are to illustrate the FDTD update equations for these techniques and to validate and demonstrate these techniques for one-dimensional problems involving reflections from dispersive dielectric half-spaces. Numerical results are compared with several other dispersive medial FDTD implementations. |
| Author(s): | J.H. Beggs, J.H. Beggs |
| File Type: | Journal Paper |
| Issue: | Volume: 14 Number: 2 Year: 1999 |
| Download Link: | Click here to download PDF File Size: 484 KB |
| Title: | Validating the Magnetostatic Frill Source with WIPL-D |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Simulation using Wipl-D Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 267 KB |
| Title: | Validating Numerical Models – Quantifying Error |
| Abstract: | |
| Author(s): | |
| File Type: | Newsletter Paper |
| Issue: | Volume: 19 Number: 1 Year: 2004 |
| Download Link: | Click here to download PDF File Size: 107 KB |
| Title: | Valence Electron High-harmonic Generation Analysis by the Finite Difference Time Domain Method |
| File Type: | Conference Paper |
| Issue: | Volume: 2-2-A Multiphysics Modeling and Simulation Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 162 KB |
| Title: | V-Band Frequency Reconfigurable Cavity-Based Bandpass Filters |
| File Type: | Conference Paper |
| Issue: | Volume: S55 Nanotechnology Number: Year: 2016 |
| Download Link: | Login To Download (For Members) File Size: 410 KB |
| Title: | V Transmission lines Frequency Operation Band |
| File Type: | Conference Paper |
| Issue: | Volume: Microwave, Optical Devices, and Propagation Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 384 KB |
| Title: | UWB-MIMO Quadruple with FSS-Inspired Decoupling Structures and Defected Grounds |
| Abstract: | In this paper, a quad element Ultra Wideband Multiple-Input Multiple-Output (UWB-MIMO) antenna system is presented. The proposed design is compact as it has four semielliptical shaped antennas along with the decoupling structures, fabricated on a compact substrate. The substrate employed is a low cost FR-4 laminate. The antenna elements are decoupled by employing Defected Ground Structures (DGS) and structures inspired from Frequency Selective Surfaces. An enhanced impedance match over lower to medium band is achieved by introducing dipole-like parasitic stubs on rear sides of the antennas. Measured results show that the isolation achieved by the proposed design is more than 20 dB over desired frequency band. |
| Author(s): | T. Shabbir, R. Saleem, A. Akram, F. Shafique |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 2 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 1186 KB |
| Title: | UWB Square Monopole Antenna with Omni-Directional Radiation Patterns for Use in Circular Cylindrical Microwave Imaging Systems |
| Abstract: | In this paper, a novel ultra-wideband printed monopole antenna (PMA) for the use in a circular cylindrical microwave imaging system is presented. The proposed antenna consists of a square radiating patch and a ground plane with a pair of L-shaped slots and two L-shaped conductor back plane, which provides a wide usable fractional bandwidth of more than 130 % (3.02 GHz - 15.21 GHz). By cutting two modified Lshaped slots with variable dimensions on the ground plane corners and also by inserting two Lshaped conductor back plane on the other side of the substrate, additional resonances are excited and hence much wider impedance bandwidth can be produced, especially at the higher band. The proposed antenna has an ordinary square radiating patch, therefore displays a good omni-directional radiation pattern even at higher frequencies, and also its radiation efficiency is greater than 82% across the entire radiating band. The designed antenna has a small size of 12 × 18 mm2. Simulated and measured results are presented to validate the usefulness of the proposed antenna structure for circular cylindrical microwave imaging system. |
| Author(s): | N. Ojaroudi, M. Ojaroudi, N. Ghadimi, M. Mehranpour |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 2 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 542 KB |
| Title: | UWB Slot Antenna with Band-Stop Operation by Using H-Shaped Parasitic Structures for UWB Applications |
| Abstract: | A novel ultra wideband (UWB) printed slot antenna with band-notched performance is designed and manufactured. In order to increase the impedance bandwidth of the slot antenna, we use a rectangular slot with an H-shaped parasitic structure inside the rectangular slot on the feedline that with this structure UWB frequency range can be achieved. Additionally, by using a square ring radiating stub with a rotated H-shaped parasitic structure inside the square ring, a frequency band-stop performance has been obtained. The designed antenna has a small size of 20 × 20 mm2 while showing the radiation performance in the frequency band of 2.97 GHz to over 12.39 GHz with a band rejection performance in the frequency band of 5.01 GHz to 5.98 GHz. Simulated and experimental results obtained for this antenna show that it exhibits good radiation behavior within the UWB frequency range. |
| Author(s): | M. Ojaroudi, N. Ojaroudi, N. Ghadimi |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 12 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 448 KB |
| Title: | UWB Slot Antenna with Band-Notched Property with Time Domain Modeling based on Genetic Algorithm Optimization |
| Abstract: | This paper presents a kind of band-notched slot antenna with time domain designing method for ultra-wideband (UWB) applications. The proposed antenna consists of a square radiating stub with a defected mircostrip feed-line using an M-shaped step impedance resonator (SIR) slot and a defected ground plane with a pair of inverted U-shaped slots. By cutting two inverted U-shaped slots in the ground plane, a new resonance at the higher frequencies is excited and hence much wider impedance bandwidth can be produced that. To generate a band-notched characteristic, we use an M-shaped slot at the feed-line. The proposed antenna can operate from 3.03 to 13.21 GHz with frequency band-notched function in 7.28-7.79 GHz to avoid interference from downlink of X-band satellite communication systems. To verify the validation of the proposed antenna an equivalent circuit based on time domain reflectometry (TDR) analysis is presented. In addition, the accuracy of the equivalent circuit models have been improved using Genetic algorithm optimization (GAP). Detailed simulation and numerical investigations are conducted to understand their behaviors and optimize for broadband operation. The proposed antenna exhibits almost omni-directional radiation patterns in UWB frequency range and could be used in wireless systems. |
| Author(s): | J. Zolghadr, Y. Cai, N. Ojaroudi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 8 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1770 KB |
| Title: | UWB Sampler for Wireless Communications and Radar |
| File Type: | Conference Paper |
| Issue: | Volume: Technologies for Ultra-Wideband Communication Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 167 KB |
| Title: | UWB Monopole Antenna with WLAN Frequency Band-Notched Performance by using a Pair of E-Shaped Slits |
| Abstract: | In this paper an ultra-wideband monopole antenna with frequency band-stop performance is designed and manufactured. The proposed antenna consists of square radiating patch with two E-shaped slits and a ground plane with a protruded T-shaped strip inside the rectangular slot. In the proposed structure, by inserting a rectangular slot with a T-shaped strip protruded inside the slot on the ground plane, additional resonance is excited and hence, much wider impedance bandwidth can be produced, especially at the higher band. In order to create band-rejected function we use two E-shaped slits in the square radiating patch. The fabricated antenna has the frequency band of 3 GHz to over 12.7 GHz with a rejection band around 5 GHz – 6 GHz. Good VSWR and radiation pattern characteristics are obtained in the frequency band of interest. Simulated and measured results are presented to validate the usefulness of the proposed antenna structure for UWB applications |
| Author(s): | N. Ojaroudi, M. Ojaroudi, N. Ghadimi |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 12 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 403 KB |
| Title: | UWB Monopole Antenna with Switchable Band-Notch Characteristic Using a Novel MEMS Afloat |
| Abstract: | In this paper, a novel microelectro-mechanical system (MEMS) U-shaped afloat is designed and used instead of a simple slot to activate and deactivate the band notch characteristic of an ultra wideband (UWB) monopole antenna at the WLAN band (5.15-5.825 GHz) without extra DC bias lines. The novelty of this work is design of MEMS afloat that can stay in down state permanently. When the dc actuation voltage, about 20 volts, is applied to the microstrip center line, the ?/2 long U-shaped afloat moves down and creates a slot (resonating element) in its vacant place. Whereas no voltage is applied, the afloat remains in the up position and serves as a part of the antenna, which eliminates the resonance. The proposed design for MEMS afloat has least negative effect on gain, reflection coefficient, and pattern of the antenna. The gain of the antenna is about 3.2 dBi over the entire UWB frequency band (3.1-10.6 GHz), while it decreases sharply over 7 dB at the rejection band. More-over, the time-domain characteristics of the antenna is investigated, which shows 1 ns delay over the UWB frequency band for 20 cm. Due to a novel afloat design, the addition of the resonance element does not affect on the radiation performance, reflection coefficient, gain, and group delay of the antenna outside of notched band frequencies. |
| Author(s): | A. Nemati, B. A. Ganji |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 12 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 1070 KB |
| Title: | UWB Monopole Antenna with Dual Band-Stop Performance Using G-Shaped SRR and SIR Structures at Feed Line |
| Abstract: | This article presents a new design of ultra-wideband monopole antenna with the characteristics of dual band rejection .The antenna consists of a circular radiating patch, a feed-line with G-shaped Step-Impedance Resonator (SIR) slot and Split-Ring Resonator (SRR) structure, and a ground plane which provides a wide usable fractional bandwidth of more than 120% with two notch bands around 5.15-5.35 GHz and 7.25-7.75 GHz, to avoid interferences from High Performance Radio Local Area Networks (HIPERLAN) and downlink frequency of X-band satellite systems. The simulated and measured results show that the antenna design exhibits an operating bandwidth (VSWR<2) from 2.86 to 12.92 GHz, excluding the rejected bands. The proposed antenna configuration is simple, easy to fabricate and can be integrated into any UWB system. The antenna has an ordinary circular-disc radiating patch, therefore displays good omnidirectional radiation patterns, even at higher frequencies. |
| Author(s): | S. Ojaroudi, Y. Ojaroudi, N. Ghadimi, N. Ojaroudi |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 10 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 761 KB |
| Title: | UWB Monopole Antenna with Dual Band-Notched Function |
| Abstract: | In this letter, an Ultra-Wideband (UWB) monopole antenna with dual frequency band-stop performance is designed and manufactured. In the proposed structure, by inserting an S-shaped parasitic structure inside a square slot in the ground plane a new resonance at higher frequencies can be achieved, which provides a wide usable fractional bandwidth of more than 125%. In order to generate dual bandnotched function, we use four L-shaped strips protruded inside square ring. The measured results reveal that the antenna offers a very wide bandwidth from 2.63 to 14.2 GHz with two notched bands covering all the 5.2/5.8 GHz WLAN, 3.5/5.5 GHz WiMAX and 4 GHz C bands. Good VSWR and radiation pattern characteristics are obtained in the frequency band of interest. |
| Author(s): | Y. Ojaroudi, S. Ojaroudi, N. Ojaroudi |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 2 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 523 KB |
| Title: | UWB Monopole Antenna with Compact Polygon-Shaped Patch for Portable Devices |
| Abstract: | In this paper, a small ultra wideband (UWB) antenna with co-planar waveguide (CPW) feed, consisting of a polygon-shaped design on the patch and a ground plane truncated with two mirror rectangular–shaped notches is designed for ultra wideband (UWB) applications. In this proposed antenna, through increasing the number of cuts inside the initial patch, a proper control on the upper frequency of the band can be achieved. The overall dimension of the antenna is 19×19 ×1 mm3 and fed by 50 ? coplanar waveguide. The proposed antenna is developed and its VSWR is compared with the simulated result. The proposed antenna operates in the adopted bandwidth (3.1 GHz-10.6 GHz) with VSWR < 2, and covers it very well from 3 GHz to 14.9 GHz, which provides fractional bandwidths of more than 132%. The effect of the ground plane notch on the optimization of the VSWR is discussed in detail. |
| Author(s): | T. Sedghi, V. Rafii, M. Moosazadeh |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 1 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 900 KB |
| Title: | UWB MIMO Antenna with Decoupling Strip for 5G Applications |
| File Type: | Conference Paper |
| Issue: | Volume: S47 Advanced Antenna Designs for Emerging Wireless Applications Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 624 KB |
| Title: | UWB MIMO Antenna for High Speed Wireless Applications |
| Abstract: | The paper proposes a MIMO antenna composed of two elements in the form of UWB monopole antennas. Polarization diversity of the proposed antenna is obtained locating the two elements perpendicularly on a common substrate. Also the isolation between elements is accomplished without using any extra decoupling structures. The two monopoles antennas with half elliptical shape are fed with asymmetric coplanar strip (ACS). The presented antenna is located on substrate 48 × 28 mm2 in total size. The distance between the two elements is 15 mm that is 0.15λ0 at 3GHz. The antenna was designed to work effectively from 3 to 11.5 GHz with reflection coefficient better than -10 dB and isolation lower than 18 dB. In addition, antenna with elements located in parallel was designed to show the advantage of the original design. Envelope correlation coefficient, diversity gain and channel capacity loss document the antennas behavior. The antenna was fabricated and measured. Measurement validated the simulation and showed that the designed antenna can be well applied in UWB MIMO systems. |
| Author(s): | A. A. Ibrahim, J. Machac, R. M. Shubair |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 9 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1778 KB |
| Title: | UWB Microstrip-Fed Slot Antenna with Band-Rejection Performance Using an SRR Conductor-Backed Plane |
| Abstract: | In this article, a novel and compact ultra-wideband (UWB) slot antenna with bandnotched function is presented. This antenna consist of a square radiating stub, a 50? microstrip feedline, a ground plane with a pair of rotated Tshaped strips protruded inside square slots and a Split Ring Resonator (SRR) conductor-backed plane. In this design, by cutting a pair of modified square slots with rotated T-shaped strips protruded inside slots, additional resonance is excited and hence much wider impedance bandwidth can be produced. In order to achieve a band-notched function, an SRR parasitic structure was inserted in the ground plane. The measured results show that the proposed antenna can achieve the Voltage Standing Wave Ratio (VSWR) requirement of less than 2.0 in frequency range from 3.1 GHz to 13.15 GHz, with band-rejection performance of 5.08 GHz to 6 GHz, to avoid interference from WLAN communications. The presented microstrip-fed slot antenna exhibits good radiation behavior. The antenna has a small size. |
| Author(s): | N. Ojaroudi, N. Ghadimi, Y. Ojaroudi |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 3 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 691 KB |
| Title: | UWB Gain Enhancement of Horn Antennas Using Miniaturized Frequency Selective Surface |
| Abstract: | In this work, enhancement of the radiation performances of horn antennas are worked out within their operation bandwidth by placing the miniaturized Frequency Selective Surface (FSS)s perpendicularly into the inner part of their flares. Here each FSS consists of only a single miniaturized double-sided inverted Tshaped square unit cell designed on the low-cost FR4 with relative permittivity 4.4, loss tangent 0.0035 and thickness 1.58 mm in 3D CST environment so that it is able to focus the propagating electromagnetic waves to increase the directivity properties like a dielectric lens, while keeping the mismatching characteristics with less size and low manufacturing cost compared to its counter parts. Herein an exponentially tapered TEM horn with the operation bandwidth of 5-13 GHz is taken as an example horn antenna for measurements. From the measured results of the prototyped module, it can be observed that the proposed module keep mismatching characteristics of the horn antenna, meanwhile the gain and beam widths are enhanced to amplify the signal in the operation band without any increase in the total volume of the module or making the design bulky. Thus, it is expected that this methodology can be implemented to horn antennas effectively reducing volume and cost of communication systems. |
| Author(s): | M. A. Belen, F. Gunes, P. Mahouti, A. Belen |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2272 KB |
| Title: | UWB Compact TEM Ridged Horn Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: Application of Electromagnetic Simulation for Designing and Analysis of Antennas and Radio Propagations Part I Number: Year: 2014 |
| Download Link: | Login To Download (For Members) File Size: 322 KB |
| Title: | Utilizing Particle Swarm Optimization in the Field Computation of Non-Linear Magnetic Media |
| Abstract: | It is well known that the computation of magnetic fields in nonlinear magnetic media my be carried out using various techniques. In the case of problems involving complex geometries or magnetic media, numerical approaches become especially more appealing. The purpose of the paper is to present an automated particle swarm optimization approach using which field computations may be carried out |
| Author(s): | A. A. Adly, S. K. Abd-El-Hafiz, A. A. Adly, S. K. Abd-El-Hafiz |
| File Type: | Journal Paper |
| Issue: | Volume: 18 Number: 3 Year: 2003 |
| Download Link: | Click here to download PDF File Size: 222 KB |
| Title: | Utilizing Hybrid Dielectric-Metal and Mesh Refinement Techniques When Modeling a MMIC in Concerto Quickwave |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Modeling with QuickWave/Concerto Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 344 KB |
| Title: | Utilization of Protruded Strip Resonators to Design a Compact UWB Antenna with WiMAX and WLAN Notch Bands |
| Abstract: | In this paper, a new design of ultrawideband (UWB) microstrip monopole antenna is presented. The main novelty of the proposed structure is the using of protruded strips as resonators to design an UWB antenna with dual band-stop property. In the proposed design, by cutting the rectangular slot with a pair of rotated Y-shaped strips in the ground plane, additional resonance is excited and much wider impedance bandwidth can be achieved. To make a single band-notched function, the square radiating patch is converted to the square-ring structure with a pair of protruded fork-shaped strips. Finally, by cutting a rectangular slot with a protruded M-shaped strip at the feed line, a desired dual band-notched function is achieved. The measured results reveal that the presented dual band-notched antenna offers a very wide bandwidth from 2.8 to 11.6 GHz, with two notched bands, around of 3.3-3.7 GHz and 5-6 GHz covering all WiMAX and WLAN bands. |
| Author(s): | J. Mazloum, N. Ojaroudi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 684 KB |
| Title: | UTD Shooting-and-Bouncing Extension to a PO/PTD Ray Tracing Algorithm |
| Abstract: | This paper deals with the efficient combination of three well-established electromagnetic modeling methods, a Shooting-and-Bouncing-Rays (SBR) algorithm on the basis of the Geometrical Optics (GO), a source-based calculation of scattered field strengths using Physical Optics (PO) and Physical Theory of Diffraction (PTD), and diffraction calculation on the basis of the Uniform Theory of Diffraction (UTD). While the conventional GO-PO/PTD methods are able to accurately calculate wedge contributions to scattered fields, the further propagation of diffracted rays is generally not considered in SBR approaches. Thus, the aim of this paper is to describe the implementation of diffracted rays according to the UTD concept into an SBR code. This novel implementation allows for the modeling of double diffraction and reflected-diffractedreflected paths in complex scenarios consisting of a very large number of surface elements as well as the accurate simulation of cavities. The comparison with numerically exact reference simulations proves that the proposed hybrid GO/UTD-PO/PTD algorithm yields excellent results and that the UTD-SBR extension definitely improves the simulations of the ray tracing algorithm also for realistic objects. |
| Author(s): | F. Weinmann |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 3 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 526 KB |
| Title: | UTD Ray and Beam Methods for Analysis of Large EM Wave Problems Abstract |
| File Type: | Tutorial Abstract |
| Issue: | Volume: S35 UTD Ray and Beam Methods for Analysis of Large EM Wave Problems Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 92 KB |
| Title: | Using YATPAC for Modeling of a Marchand Balun |
| File Type: | Conference Paper |
| Issue: | Volume: MEFiSTo Modeling and Analysis Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 189 KB |
| Title: | Using Transfer Function Approach To Develop MRI Visible and Low RF Heating Sleeve for Cardiac Applicaion |
| File Type: | Conference Paper |
| Issue: | Volume: S54 Computational Electromagnetic Modeling in EMC Applications Number: Year: 2016 |
| Download Link: | Login To Download (For Members) File Size: 300 KB |
| Title: | Using Time-domain Codes to Find RF Cavity Eigenmodes |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Finite Difference Time Domain Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 29 KB |
| Title: | Using the Feature Selective Validation Technique to Compare Data Sets |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Numerical EM and Propagation Tools Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 655 KB |
| Title: | USING THE FDTD METHOD TO MODEL THE REFLECTION COEFFICIENT OF A VIVALDI TAPERED SLOT ANTENNA FED THROUGH A PLANAR BALUN |
| Abstract: | In this paper, the Time-Domain (FDTD) method was used to determine the reflection coefficient vs. frequency of a Vivaldi Tapered Dual-Slot Antenna fed through a planar balun. The reflection coefficient at the input port of the feed stripline was determined through the separate computation of the reflection coefficient of representation of the antenna section and the scattering matrix of the balun, assuming that the electromagnetic coupling between these sections was negligible. Experimental results, which were obtained on a prototype of this structure, confirmed the validity of the proposed approach and demonstrate that the coupling of the model. [Vol. 12, No. 3 (1997), pp 26-30] |
| Author(s): | G. Biffi Gentili, R Braccini, M. Leoncini, G. Biffi Gentili, R Braccini, M. Leoncini |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 3 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 308 KB |
| Title: | Using the Best Uniform Approximation with Compression for Efficient Computation of Monostatic Scattering |
| Abstract: | The best uniform approximation method hybridized with Singular Value Decomposition (SVD) is proposed to reduce the time requirement for computation of monostatic Radar Cross Section (RCS). In contrast to our previous work, the traditional best uniform approximation technique is applied to compute the key excitation vectors instead of electric current vectors. Reduction of the number of multiple excitation vectors can lead to significantly reduced computation time. Furthermore, with low-rank property, the key excitation vectors could be further compressed by SVD, resulting in a more efficient method. Numerical results demonstrate that the proposed method is efficient for monostatic RCS calculation with high accuracy. |
| Author(s): | Z. Liu, S. He, X. Zhang, Y. Liu, Y. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 11 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 603 KB |
| Title: | Using System-Theoretical Consideration for Calculating Coupling Effects in Packages |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in CEM Applications I Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 421 KB |
| Title: | Using Superformula to Miniaturize CPW Rat Race Coupler |
| Abstract: | This paper proposes a new CPW rat race coupler whose shape has been meandered using the superformula for size reduction. The coupler operates at a center frequency of 1.8 GHz. The size reduction in the proposed design is about 74% as compared to conventional ring rat race coupler. The bandwidth of the proposed coupler defined by |S11| < -15 dB is about 31.6%. |
| Author(s): | A. A. Omar, N. I. Dib |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 12 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1901 KB |
| Title: | USING NONUNIFORM SEGMENTS LENGTHS WITH NEC TO ANALYZE ELECTRICALLY LONG WIRE ANTENNAS |
| Abstract: | In this paper an electrically long monopole is analyzed using the Numerical Electromagnetics Code, version two (NEC-2). Due to the electrical length of the monopole and the segment length requirement established for the NEC-2 program, the computer memory requirement and computational time become excessive. By successively increasing the segment length with distance from the source, very large structures can be analyzed accurately and efficiently. Various schemes for selecting the segment lengths are considered, and the results are compared to those obtained by using a large number of electrically short segments. This technique of grading segment lengths allows one to employ NEC-2 to analyze other electrically long wire antennas. [Vol. 5, No. 2, pp. 2-16 (l990)] |
| Author(s): | Saad N. Tabet, J. Patrick Donohoe, Clayborne D. Taylor, Saad N. Tabet, J. Patrick Donohoe, Clayborne D. Taylor |
| File Type: | Journal Paper |
| Issue: | Volume: 5 Number: 2 Year: 1990 |
| Download Link: | Click here to download PDF File Size: 689 KB |
| Title: | Using Near Field Equivalent Sources in Combination with Large Element Physical Optics to Model a Slant 45 Degree Omni Directional Antenna over Ground |
| File Type: | Conference Paper |
| Issue: | Volume: S03 EM Modeling using Feko/WinProp Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 426 KB |
| Title: | Using Near Field Equivalent Sources in Combination with Large Element Physical Optics to Model a Slant 45 Degree Omni Directional Antenna over Ground |
| Abstract: | This paper compares the theoretical and measured antenna patterns of a slant 45-degree antenna on a rolled edge ground plane. Advantages of using sampled nearfield currents in combination with large element physical optics in determining the reflected far fields will be described. |
| Author(s): | K. Snyder |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 11 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1397 KB |
| Title: | 3B-SPLINES IN THE INTEGRAL EQUATION SOLUTION FOR SCATTERING FROM BODIES OF REVOLUTION |
| Abstract: | The use of B-Splines functions is investigated in conjunction with the Method of Moments integral-equation solution to the problem of scattering from conducting bodies of revolution. Its computational performance in terms of relative accuracy and storage/CPU time requirements is evaluated against entire-domain and sampling-like basis functions. Particular attention is given to the description of current near edges. Questions of time (space) and frequency (wavenumber) localization are also addressed. A simple scheme devised to enforce boundary conditions a priori is shown to potentially capable to stgabilize otherwise spurious solutions |
| Author(s): | F.L. Teixeira, J.R. Bergmann, F.L. Teixeira, J.R. Bergmann |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 532 KB |
| Title: | ELECTROMAGNETIC PROPERTIES OF A CHIRAL-PLASMA MEDIUM |
| Abstract: | The theoretical properties of a composite chiral-plasma medium are devel- oped. Using the reaction theorem, we obtain the proof of nonreciprocity based upon the constitutive relationships between the electromagnetic vectors E, B, H, D. Using the Maxwell's equations and the proposed constitutive relations for a chiral- plasma medium, we derive the E, and H, vector equations and from these equations, dispersion relations and E-field polarizations are found. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 14-18] MTRT - A MODIFIED TRANSVERSE RESONANCE TECHNIQUE |
| Author(s): | Hector Torres-Silva, Norma Reggiani, Paulo H. Sakanaka, Hector Torres-Silva, Norma Reggiani, Paulo H. Sakanaka |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 283 KB |
| Title: | MTRT - A MODIFIED TRANSVERSE RESONANCE TECHNIQUE |
| Abstract: | In this work a modified formulation of the transverse resonance technique (TRT) is presented. The difference between the usual TRT and the formulation presented here, MTRT, is the equivalent network considered. With the MTRT proposed formulation, mode solution identification requires less arduous work. The complete equation set is described. Numerical results are presented for dispersion characteristics of microstrip lines, coupled microstrip lines and conductor-backed coplanar waveguides (CBCW). When compared to results obtained by other methods, a good agreement is observed. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 19-25] |
| Author(s): | Alfredo Gomes Neto, Creso S. da Rocha, Herve' Aubert Aubert, D. Bajon, H. Baudrand, Alfredo Gomes Neto, Creso S. da Rocha, Herve' Aubert Aubert, D. Bajon, H. Baudrand |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 303 KB |
| Title: | EFFECT OF THE MAGNETIC ANISOTROPY ON THE CHARACTERISTICS OF MICROSTRIP ANTENNAS WITH SEVERAL LAYERS |
| Abstract: | The main objective of this work is to show how the properties of a ferrimagnetic material change the characteristics of a microstrip patch with several layers. Particularly, it is investigated how the resonant frequency and the radiation pattern are changed by varying the ferrimagnetic layer thickness or the magnitude and/or direction of the external applied magnetic field. The analysis is carried on by using Hertz potentials and Galerkin method. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 26-29] |
| Author(s): | Jose de Ribamar Silva Oliveira, Adaildo Gomes d'Assunc o, Jose de Ribamar Silva Oliveira, Adaildo Gomes d'Assunc o |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 244 KB |
| Title: | DISPERSIVE ANALYSIS OF CIRCULAR CYLINDRICAL MICROSTRIPS AND BACKED SLOTLINES |
| Abstract: | In this work, the full-wave analysis of circular cylindrical microstrips and backed slotlines is performed, by using a combination of Hertz vector potentials and Galerkin method. The analysis is developed in the spectral domain. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 30-33] |
| Author(s): | Laercio Martins de Mendonca, Adaildo Gomes d'Assunc o, Laercio Martins de Mendonca, Adaildo Gomes d'Assunc o |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 268 KB |
| Title: | FINITE ELEMENT ANALYSIS AND EVALUATION OF ELECTROMAGNETIC FIELDS GENERATED BY ATMOSPHERIC DISCHARGES |
| Abstract: | A lightning return stroke channel is modeled by a high loss transmission line. The differential equations that represent its dynamic behavior are solved by the application of the one-dimensional finite element method (FEM). By the combination of FEM results with the use of Maxwell equations applied to the dipole method, electric and magnetic (EM) fields are evaluated at various positions in space. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 34-38] |
| Author(s): | E.H.R Coppoli, R.R. Saldanha, A. Konrad, E.H.R Coppoli, R.R. Saldanha, A. Konrad |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 318 KB |
| Title: | POINT-MATCHED TIME DOMAIN FINITE ELEMENT METHOD APPLIED TO MULTI-CONDUCTOR ELECTROMAGNETIC TRANSIENTS ANALYSIS. |
| Abstract: | A point-matched time domain finite element method (TDFE) applied to the analysis of electromagnetic transients in multi-conductor transmission line network is presented. The TDFE method solves the partial differential transmission line equations based on a semi-discrete approximation using the finite element method and leap-frog scheme. Some oscillations can occur due to the stability condition of the technique. Using the modal analysis these oscillations can be eliminated. A surge propagation in a simple multi-conductor network is presented and the results are compared with the Electromagnetic Transients Program (EMTP) simulations. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 39-43] |
| Author(s): | Glassio Costa de Miranda, Glassio Costa de Miranda |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 319 KB |
| Title: | ERROR ESTIMATORS IN SELF-ADAPTIVE FINITE ELEMENT FIELD CALCULATION |
| Abstract: | The aim of this paper is to present different error estimates to improve accuracy in linear and nonlinear self-adaptive finite element field calculation. The first estimator is based on the polynomial theory, the second one makes an estimation of the flux density divergence, the third one is linked to a magnetomotive force associated to elements sides, and the fourth one is based on the use of the bilinear element. All methods were implemented in our software named LMAG2D developed at "Escola Politecnica da Universitade de S o Paulo", Brazil. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 44-49] |
| Author(s): | L. Lebensztajn, J.R. Cardoso Cardoso, L. Lebensztajn, J.R. Cardoso Cardoso |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 386 KB |
| Title: | TRANSIENT VOLTAGE AND ELECTRIC FIELD DISTRIBUTIONS IN AIR CORE REACTORS |
| Abstract: | This work presents a computational model for the evaluation of transient voltage and longitudinal electric field distributions in single layer air core reactors. The influence of a grounded shielding concentric to the reactor is considered. The validity of the model is verified by comparing computed and measured voltage responses at three taps of a test reactor. Analyses showing the influence of the grounded shielding, front time and front wave shape of the applied voltage on the maximum longitudinal electric stresses along the reactor winding are presented. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 50-55] |
| Author(s): | S. L. Varricchio, N. H. C. Santiago, S. L. Varricchio, N. H. C. Santiago |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 324 KB |
| Title: | CALCULATION OF ELECTRIC FIELD CREATED BY TRANSMISSION LINES, BY 3D-FE METHOD USING COMPLEX ELECTRIC SCALAR POTENTIAL |
| Abstract: | This paper presents a methodology for tridimensional analysis of the electric field produced by transmission lines. It utilizes the complex electric scalar potential, which makes it possible to consider variation of module and phase in the voltages of supply lines. The Finite Element Method (FEM) is applied to solve the differential equation that describes the phenomenon in the domain of this study. Finally, a comparison is established between the results obtained applying the proposed methodology and the values reached through the classical method of charge simulation. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 56-60] |
| Author(s): | Ricardo Marcal Matias, Adroaldo Raizer, Ricardo Marcal Matias, Adroaldo Raizer |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 330 KB |
| Title: | ADAPTIVE FINITE ELEMENT MESH REFINEMENT AND 'A POSTERIORI' ERROR ESTIMATION PROCEDURES FOR ELECTROMAGNETIC FIELD COMPUTATION |
| Abstract: | Adaptive Finite Element (FE) mesh refinement combined with a robust and functionally reliable error estimate provides nearly optimal solution accuracy. The efficiency of adaptivity depends on the effectiveness of the mesh refinement algorithm and also on the availability of a reliable and computationally inexpensive error estimation strategy. An adaptive mesh refinement algorithm utilizing a hierarchical minimal tree based data structure for 2D and 3D problems is discussed in this paper. Two different 'a posteriori' error estimation schemes, one based on the local element by element method and the other using the gradient of field approach are also presented. The usefulness of the mesh refinement algorithm and the error estimation strategies are demonstrated by adaptively solving a set of 2D and 3D linear boundary value problems. The performance of the error estimates is also verified for adaptive modeling of a nonlinear problem involving the design of a permanent magnet synchronous machine. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 61-68 |
| Author(s): | K.C. Chellamuthu, Natan Ida, Q.k. Zhang, K.C. Chellamuthu, Natan Ida, Q.k. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 656 KB |
| Title: | DESIGN OF ELECTRICAL MACHINES AIDED BY FIELD CALCULATION AND FACTORIAL EXPERIMENTS METHOD |
| Abstract: | An approach for electrical machines design by using magnetic field computation coupled to factorial experiments is presented in this paper. Principles of factorial experiments are briefly reviewed and their application to design optimisation is explained. In this application experiments are replaced by magnetic field calculations. The procedure, which performs automatically all the numerical field calculations required, is described. The whole procedure is applied to a typical problem concerning permanent magnets synchronous motor with polar pieces. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 69-73] |
| Author(s): | C. Pertusa, S.Astier, Y.Lefevre, M.Lajoie-Mazenc, C. Pertusa, S.Astier, Y.Lefevre, M.Lajoie-Mazenc |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 317 KB |
| Title: | LIMITATIONS OF THE CONVENTIONAL METHODS OF FORCE AND TORQUE PREDICTION |
| Abstract: | The calculation of forces and torques developed in electromechanical devices, and their variation with changes in position or excitation, is often what the designer is, ultimately, interested in. This paper addresses some of the problems associated with the force and torque calculations based on numerical field solutions for 2-D magnetostatic problems. The problem of calculating the cogging torque characteristic of a neodymium-iron-boron permanent-magnet motor is considered and the technique of torque measurement is described briefly. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 74-79] |
| Author(s): | Antonio Flavio Licari o Nogueira, Antonio Flavio Licari o Nogueira |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 480 KB |
| Title: | COMPARISON OF CONVERGENCE RATES OF EDGE AND NODAL FINITE ELEMENTS FOR MAGNETOSTATIC PROBLEMS |
| Abstract: | Mathematical theory is used to obtain convergence estimations for magnetostatic formulations using nodal and edge elements. Numerical results of two closed boundary problems that confirm the theory are presented. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 80-83] |
| Author(s): | M. L. y Gonzalez, R. C. MesquitaM. L. y GonzalezMesquita, J. P. A. Bastos, M. L. y Gonzalez, R. C. MesquitaM. L. y GonzalezMesquita, J. P. A. Bastos |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 231 KB |
| Title: | FINITE ELEMENT SIMULATION OF AN OUT-OF-PHASE SYNCHRONIZATION OF A SYNCHRONOUS MACHINE |
| Abstract: | This paper presents the finite element simulations of the out-of-phase synchronization of a synchronous machine with an external electric system. Two cases were analysed regarding to the phase angle: 120 and 180 . Computed results are analysed and compared to analyticalvalues.[Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 84-89] |
| Author(s): | Silvio Ikuyo Nabeta, Albert Foggia, Jean-Louis Coulomb, Gilbert Reyne, Silvio Ikuyo Nabeta, Albert Foggia, Jean-Louis Coulomb, Gilbert Reyne |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 306 KB |
| Title: | A 3D FINITE-ELEMENT COMPUTATION OF STATOR END-WINDING LEAKAGE INDUCTANCE AND FORCES AT STEADY STATE OPERATING CONDITIONS IN LARGE HYDROGENERATORS |
| Abstract: | The forces acting on the stator end windings of a hydrogenerator at steady state operating conditions, as well as the end-winding leakage inductance, are calculated using a 3D finite element package. A more realistic representation for the geometry of the windings and boundaries is considered. The effects of different representations for the stator core end surface are outlined. The computed values of the inductance from time harmonic and static simulations are presented and compared with classical analytical methods. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 90-96] |
| Author(s): | Viviane Cristine Silva, Albert Foggia, Viviane Cristine Silva, Albert Foggia |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 520 KB |
| Title: | IMPROVING THE CHARGE SIMULATION METHOD FOR THE COMPUTATION OF HIGH VOLTAGE ELECTRIC FIELDS WITH EFFICIENT LEAST SQUARES TECHNIQUES |
| Abstract: | The well known Charge Simulation Method, which is commonly used for electric field calculations, is shown to be a particular and ill-conditioned case of the Least Squares Charge Simulation Method. By solving a practical problem, it is shown how to efficiently handle a least squares problem, thus obtaining results of higher precision if compared to the traditional Charge Simulation Method For the solution of the resulting linear system, several mathematical methods are analyzed and compared, being stated that the optimum combination of higher precision, lesser error propagation, lesser CPU time and lesser computer RAM are simultaneously reached when applying the Least Squares Charge Simulation Method, solved with the QR decomposition and Householder transformations. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 97-102] |
| Author(s): | J. N. Hoffmann, P. Pulino, J. N. Hoffmann, P. Pulino |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 467 KB |
| Title: | A HYBRID FINITE DIFFERENCES, AND CHARGE SIMULATION METHOD FOR THE COMPUTATION OF HIGH VOLTAGE ELECTRIC FIELDS |
| Abstract: | A new treatment is proposed to the hybrid method of Finite Differences and Charge Simulation for the computation os electric fields, entirely applicable to the similar hybrid method of Finite Element and Charge Simulation. The resulting system of linear equations is solved by using the fixed point theory, the QR decomposition and the Conjugate Gradients Squared method with a preconditioning technique. New procedures are suggested for the discretization of the boundary conditions, which lead to results with higher precision. Case studies are included. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 103-110] |
| Author(s): | J. N. Hoffmann, P. Pulino, J. N. Hoffmann, P. Pulino |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 593 KB |
| Title: | FINITE ELEMENT MODELING OF ELECTRICAL MACHINES BY SIMULTANEOUS RESOLUTION OF FIELDS AND ELECTRIC CIRCUITS EQUATIONS |
| Abstract: | In this work, we present a methodology for solving simultaneously the equations of magnetic fields and electric circuits of electrical machines. To consider the magnetic phenomena the Finite Element method is used. The machines are voltage fed and, thus, the electric circuit equations are present in the matricial system which takes into account both physical aspects. A time stepping technique is employed to simulate the steady and transient states. As result, we obtain the magnetic vector potential describing the magnetic behavior of the machine and the current established in the exciting coils. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 111-116] |
| Author(s): | N. Sadowski, R. Carlson, J. P. A. Bastos, M. Lajoie-Mazenc, N. Sadowski, R. Carlson, J. P. A. Bastos, M. Lajoie-Mazenc |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 443 KB |
| Title: | SHAPE DESIGN OPTIMIZATION OF POWER FREQUENCY ELECTROMAGNETIC DEVICES USING NUMERICAL METHODS |
| Abstract: | This paper presents the mathematical formulation concerning the solution of inverse electromagnetic problems, i.e. the shape optimization of power frequency electromagnetic devices, based on a combination of numerical methods. The optimization problem is solved using deterministic methods in which the electromagnetic field problem is treated as a subproblem of the optimization process. The field problem is calculated using the finite element (FE) method. Three deterministic approaches are studied in detail, the quadratic extended penalty method (QUA), the augmented Lagrange multiplier (ALM) method and the constrained quasi-Newton method (PLBA-CR). The work highlights the advantages and drawbacks of each approach. The search direction for the optimization is found by two distinct methods, the direct differentiation of the FE matrices and the finite difference (FD) method. In total, three problems are discussed in order to show the power and applicability of the theory presented. The PLBA-CR, when combined with the direct differentiation of the FE matrices, appears to offer important advantages over the other methods. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 117-124] |
| Author(s): | Jaime A. Ramirez, Ernest M. Freeman, C. Chat-uthai, Jo o A. Vasconcelos, Jaime A. Ramirez, Ernest M. Freeman, C. Chat-uthai, Jo o A. Vasconcelos |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 485 KB |
| Title: | DETERMINATION AND ANALYSIS OF CAUSES OF INDUCTION MOTOR MAGNETIC NOISE |
| Abstract: | This paper presents the causes of the acoustic noise magnetically generated by three-phase induction electric motors and some results of tests and calculation are discussed. The influence of the rotor slots skewing on the reduction of the magnetic noise is also analysed through calculated values. The paper gives a general view about how the magnetic noise in induction motors is generated and how much its prevision is important during the design stage. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 125-131] |
| Author(s): | Sebasti o Lauro Nau, Solon Brum Silveira, Sebasti o Lauro Nau, Solon Brum Silveira |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 459 KB |
| Title: | GROUND-3D LINKED TO LINE PARAMETERS: A METHOD TO FAULT CURRENT DISTRIBUTION AND EARTH POTENTIAL DETERMINATION |
| Abstract: | In previous work [1,2] the author presents a methodology, based on finite elements method (FEM), to calculate the potential distribution influence on the grounding area. At that time the input of the solver admits as known the split of the system. The aim of this article is to demonstrate the advantages of finite element method (FEM) associated with power systems equations with lumped parameters to intrinsically obtain the distribution of fault current in several offered conductor ways and the potential distribution on the ground, simultaneously. To solve the complex equations system, the methodology adopted was that described by Mesquita [3]. . [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 132-135] |
| Author(s): | H. O. Brodskyn, M. C. Costa, J. R.Cardoso, N. M. Abe, A. Passaro, H. O. Brodskyn, M. C. Costa, J. R.Cardoso, N. M. Abe, A. Passaro |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 307 KB |
| Title: | AN INVESTIGATION OF THE SCATTERING OF SURFACE WAVES AT DIELECTRIC SLAB WAVEGUIDE WITH AXIAL DISCONTINUITY |
| Abstract: | This paper introduces a technique for studying the radiation due to an abrupt axial discontinuity in the geometry of a planar dielectric waveguide (Slab waveguide) when an even TM surface wave strikes the discontinuity. The mode matching technique is applied at the discontinu- ity giving rise to formally exact integral equations which are solved by the Method of Moments. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 136-141] |
| Author(s): | Creso S. Da Rocha, Creso S. Da Rocha |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 394 KB |
| Title: | ADAPTIVE MESHING IN TWO-VARIABLE STATIC PROBLEMS WITH FIELD BASED ERROR ESTIMATORS USING EDGE AND FACET ELEMENTS |
| Abstract: | In this paper a family of field-based error estimators for Finite Element analysis of electrostatic and magnetostatic problems in plane and axisymmetric geometries is presented. For the error estimation in magnetostatics, each element is divided in three sub-elements using an edge element approach, whereas for electrostatic problems a subdivision using facet elements is used. The methods and the numerical techniques are described, comparisons with known solutions are performed, some examples of application in cases of practical interest are reported and the obtained results are briefly discussed. . [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 142- 147] |
| Author(s): | P. Girdinio, P. Molfino, G. Molinari, M. Nervi, P. Girdinio, P. Molfino, G. Molinari, M. Nervi |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 491 KB |
| Title: | FINITE ELEMENT MODELLING SCHEMES FOR THE DESIGN AND ANALYSIS OF ELECTRICAL MACHINES |
| Abstract: | Electrical machines are complex objects. We have found that a variety of numerical techniques are required in order to model them using finite elements. We concentrate here on the different formulations which are useful in modelling such devices. Examples of modelling some of these machines using the MEGA package are described. . [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 148- 152] |
| Author(s): | D.Rodger, P.J. Leonard, H.C. Lai, N. Allen, D.Rodger, P.J. Leonard, H.C. Lai, N. Allen |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 494 KB |
| Title: | THREE DIMENSIONAL MAGNETOSTATICS USING THE MAGNETIC VECTOR POTENTIAL WITH NODAL AND EDGE FINITE ELEMENTS |
| Abstract: | In this paper, the three dimensional vector potential magnetostatic problem is solved using nodal and edge finite elements. The influence of the gauge condition A.w=0 in the characteristics of the edge-element generated matrix is analyzed. Three gauge conditions are studied: no gauge, the complete A.w=0 gauge and the incomplete A.w=0 gauge condition. [Vol. 12, No. 1 (1997), Special Issue on International Computational Electromagnetics, pp 153-156] |
| Author(s): | E. J. Silva, R. C. Mesquita Mesquita, E. J. Silva, R. C. Mesquita Mesquita |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 261 KB |
| Title: | A NEW ITERATIVE MOMENT METHOD SOLUTION FOR CONDUCTING BODIES OF REVOLUTION |
| Abstract: | An iterative solution of the combined field integral equation (CFIE) has been obtained for perfectly conducting bodies. The proposed technique avoids the inversion of the moment method (MoM) matrix by using an iterative algorithm which shows fast convergence properties, mainly for large bodies. The algorithm is applied to several 3D problems involving bodies of revolution (BOR). Accurate currents are computed with important speedups over direct MoM solutions. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 6-10] |
| Author(s): | F. Obelleiro, J. L. Rodriguez, A. G. Pino, F. Obelleiro, J. L. Rodriguez, A. G. Pino |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 1 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 319 KB |
| Title: | CALCULATION OF THE FREQUENCY CHARACTERISTICS OF MICROSTRIPS DISCONTINUITIES ON NON-DIAGONAL ANISOTROPIC SUBSTRATES USING FDTD |
| Abstract: | This paper describes modifications of the conventional finite-difference time-domain (FDTD) method to the full-wave analysis of frequency dependent characteristics of microstrips discontinuities on non-diagonal anisotropic substrates. The application of the conventional FDTD is limited to materials with diagonal-anisotropic material matrices. In this paper it is shown that this restriction can be removed: First, steps for obtaining the FDTD equations for the analysis of microstrips discontinuities on substrates with fully anisotropic permittivity matrices are derived. Then, using the Fourier transform of the computed results in the time-domain, the scattering parameters as functions of the frequency are calculated for several examples. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 11-15] |
| Author(s): | S. M. Chehrehrazi, A. R. Baghai-Wadji, S. M. Chehrehrazi, A. R. Baghai-Wadji |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 351 KB |
| Title: | ELECTROMAGNETIC WAVES IN A NONLINEAR DISPERSIVE SLAB |
| Abstract: | The electromagnetic scattering of a normal incident plane wave from a strongly nonlinear and dispersive dielectric slab is considered. The dynamics of the polarization density vector are described through a forced nonlinear ordinary differential equation of Duffing type, which takes both dispersive and nonlinear effects into account. The aim of the paper is to study the behaviour of the electromagnetic fields by using the Galerkin method. In particular it is shown that shock waves with infinite slope cannot be developed in real media because of the dispersion . [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering pp 16-19] |
| Author(s): | G. Miano, C. Serpico, L. Verolino, G. Panariello, G. Miano, C. Serpico, L. Verolino, G. Panariello |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 281 KB |
| Title: | SENSITIVITY ANALYSIS USING HIGH ORDER DERIVATIVES |
| Abstract: | In this article, we present a method of sensitivity analysis based on high order derivatives and Taylor expansion. The principle is to find a polynomial approximation of the finite element solution in terms of the sensitivity parameters. We present this method on two dimensional linear magnetostatic and linear magnetodynamic problems. The sensitivity parameters can be either physical parameters or geometric ones. Once the high order derivatives are found, the Taylor expansion allows evaluations for a new set of parameters. The time needed to obtain a new solution is negligible compared to a standard finite element re-analysis. This implies a dramatic change in the use of computational tools. Moreover, the availability of fast evaluations allows a wide use of optimization algorithms. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 20-25] |
| Author(s): | J. L. Coulomb, P. Petin, L. Saludjian, N. Nguyen Thanh, R. Pacaut, J. L. Coulomb, P. Petin, L. Saludjian, N. Nguyen Thanh, R. Pacaut |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 499 KB |
| Title: | SELF ADAPTIVE FUZZY SETS IN MULTI OBJECTIVE OPTIMIZATION USING GENETIC ALGORITHMS |
| Abstract: | Optimization in electrical engineering has attracted an increasing attention over the last few years. Various strategies to solve electromagnetic optimization problems have been introduced, amongst them stochastic, deterministic and hybrid ones. Most of today's real world applications, however, involve multiple conflicting objectives which should be considered simultaneously. The aim of this paper is to introduce self adaptive fuzzy sets to treat vector optimization problems. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 26-31] |
| Author(s): | Ch. Magele, G. Furntratt, B. Brandstatter, K.R. Richter, Ch. Magele, G. Furntratt, B. Brandstatter, K.R. Richter |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 428 KB |
| Title: | OPTIMISATION OF THE SHAPE OF THE FERROMAGNETIC CORE OF FLUXSET TYPE MAGNETIC FIELD SENSORS |
| Abstract: | A method is presented for the optimisation of the shape of the ferromagnetic core of fluxset type magnetic filed sensors. The objective of the optimisation is to find a core shape that guarantees the most homogeneous magnetisation of the core due to a given external magnetic field. By finding the optimal shape of the core the sensitivity of the sensor is improved. Since the thickness of the ferromagnetic conducting ribbon core used for fluxset sensors is considerably smaller than its other dimensions, the presence of the core is modelled by magnetic and conducting surface currents flowing in a mathematical surface representing the core. The electromagnetic field is calculated by solving an integral equation derived from the assumption of impedance type boundary conditions on the two sides of this surface. The core shape is optimised by minimising the magnetisation differences at different locations of the core. Simulated annealing procedure is used for the optimisation. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 32-37] |
| Author(s): | Jozsef Pavo, Jozsef Pavo |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 671 KB |
| Title: | NUMERICAL TECHNIQUES FOR THE INVERSION OF EDDY CURRENT TESTING DATA |
| Abstract: | In this paper, we discuss two techniques for the reconstruction of conductivity profiles in the low frequency limit. The first one is based on the second order approximation of the scattered field operator. In the second procedure, the problem is linearized at the expense of an increase in the number of unknowns including, in this case, the current density and the electric field. Some simple 2D examples are presented to point out and compare the main features of the two approaches. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 38-43] |
| Author(s): | Guglielmo Rubinacci, Antonello Tamburrino, Guglielmo Rubinacci, Antonello Tamburrino |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 573 KB |
| Title: | MAGNETIC MATERIAL PROPERTY IDENTIFICATION USING NEURAL NETWORKS |
| Abstract: | In the numerical solution of field problems for many devices, the modeling of the hysteresis properties of a material is extremely important. While considerable work has been published on models for handling this behavior, it is still difficult to obtain the parameters for these models from measured data. This paper proposes the use a neural network for this operation. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 44-49] |
| Author(s): | Hamadou H. Saliah, David A. Lowther, Hamadou H. Saliah, David A. Lowther |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 561 KB |
| Title: | OPTIMIZATION OF A SMES DEVICE UNDER NONLINEAR CONSTRAINTS |
| Abstract: | In this paper a method to calculate the gradients for the TEAM 22 problem is presented. Furthermore an objective function different from the one proposed in the benchmark is used where the energy requirement was handled as an equality constraint. The so derived gradients of the objective function and the constraints together with a standard optimization routine are used to solve the problem. In the last section some new results concerning the presence of local minima for the problem are given. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 50-53] |
| Author(s): | B. R. Brandstatter, Wolfgang Ring, B. R. Brandstatter, Wolfgang Ring |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 383 KB |
| Title: | RECONSTRUCTION OF INHOMOGENEOUS LOSSY DIELECTRIC OBJECTS IN ONE DIMENSION |
| Abstract: | The 1D inverse scattering problem of reconstructing the material properties of an inhomogeneous lossy dielectric slab is considered. The material properties are reconstructed using scattering data from time harmonic electromagnetic plane waves. The incident plane waves are either TE or TM polarized. The inverse scattering problem formulated as a nonlinear optimization problem by means of integral equations is numerically solved using an iterative scheme and Tikhonov regularization. Numerical examples with both types of polarization are presented. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 54-59] |
| Author(s): | W. Rieger, M. Haas, C. Huber, G. Lehner, W.M. Rucker, W. Rieger, M. Haas, C. Huber, G. Lehner, W.M. Rucker |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 506 KB |
| Title: | LAGRANGIAN BEM-FEM SOLUTION OF ELECTROMAGNETIC-MECHANICAL COUPLED PROBLEMS |
| Abstract: | In the framework of the electro-mechanical coupled problems, the coupling between the magnetic diffusion and the elastic deformation equations is treated numerically. A mixed BEM-FEM approach for the electromagnetic part, and a FEM approach for the mechanical part, are proposed. Advantages are taken from a Lagrangian formulation of the problem. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 60-65] |
| Author(s): | A. Formisano, R. Martone, F. Villone, A. Formisano, R. Martone, F. Villone |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 436 KB |
| Title: | MODELLING OF DEGAUSSING COILS EFFECTS ON SHIPS |
| Abstract: | This paper presents our work on magnetic modelling of ships, especially their degaussing coils. We first focus on these coils effects in the FEM computations. The main reason of bad results is a locally inadequate mesh. We propose a method named " reduced potential jump" to avoid the use of a very fine mesh. Then, comparison of results is presented for a simple geometry. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 66-70] |
| Author(s): | F. Le Dorze, J. P. Bongiraud, J. L. Coulomb, G. Meunier, X. Brunotte, F. Le Dorze, J. P. Bongiraud, J. L. Coulomb, G. Meunier, X. Brunotte |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 302 KB |
| Title: | A THREE-DIMENSIONAL ANALYSIS OF MAGNETIC SHIELDING WITH THIN LAYERS |
| Abstract: | This paper describes a numerical method for the analysis of the magnetic shielding with thin layers in three dimensional, time-harmonic magnetic fields. In this method, FEM is employed to solve a couple of differential equations which express the surface impedance of the thin shielding materials. The magnetic fields in air regions are modeled by means of BEM. The above formulations are coupled to evaluate the shielding properties. The resultant matrix equation includes unknowns of two times the number of nodal points. This method can analyze not only a shielding system with closed surfaces but also that with open surfaces without |
| Author(s): | H. Igarashi, T. Honma, A. Kost, H. Igarashi, T. Honma, A. Kost |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 288 KB |
| Title: | A C.A.E. TOOL TO UNDERSTAND MAGNETOSTATICS |
| Abstract: | We present in this paper a Computer Aided Education package allowing to visualize the magnetostatic field in and around the magnetic circuit of a double-U shaped contactor. The modeling of this device is performed by solving in real time a non-linear finite element problem. The imple- mentation of this method is optimized greatly in order to allow to animate field patterns in real time in reaction to any user interaction. An evaluation of the improvements brought by this technique to the learning capabilities of students is presented. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 81-84] |
| Author(s): | F. Buret, D. Muller, A. Nicolas, L. Nicolas, F. Buret, D. Muller, A. Nicolas, L. Nicolas |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 414 KB |
| Title: | NUMERICAL MODELLING OF AN AXIAL-FIELD SOLID DISK INDUCTION MACHINE |
| Abstract: | In this paper a method for the steady-state analysis of an axial-field induction motor with a solid disk rotor is proposed. The boundary condition for the axial component of the magnetic flux density has been calculated by means of an analytical procedure. Accordingly the simulation region is restricted to the air-gap and the rotor. Then the axial component of the diffusion equation is solved for by using a finite difference scheme. Subsequently the azimuthal component of the magnetic flux density and the current density induced in the rotor come out from the field's laws. The validity of the proposed method has been tested by comparing the numerical results with data measured on a double-stator prototype. Finally the numerical procedure has been used for the analysis of the performance of a motor for light vehicle propulsion and the results of the simulation are shown. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 85- 89] |
| Author(s): | Marco Angeli, Nunzio Esposito, Antonino Musolino, Bernardo Tellini, Marco Angeli, Nunzio Esposito, Antonino Musolino, Bernardo Tellini |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 340 KB |
| Title: | MODELLING DYNAMIC HYSTERESIS IN FERROMAGNETIC SHEETS UNDER TIME-PERIODIC SUPPLY CONDITIONS |
| Abstract: | This paper presents an application of the Dynamic Preisach Model as proposed by Bertotti, to the analysis of electromagnetic phenomena inside a ferromagnetic lamination subject to imposed time-periodic magnetic flux. The field problem, considered as one dimensional, is formulated in terms of magnetic field and the Fixed Point technique is used for the treatment of the hysteretic nonlinearity. The solution is carried out in the harmonic domain by means of the Finite Element method. The original implementation of the Dynamic Preisach Model is detailed and comparisons with measurements are presented in the case of sinusoidal excitations. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 90-95] |
| Author(s): | Oriano Bottauscio, Mario Chiampi, Maurizio Repetto, Oriano Bottauscio, Mario Chiampi, Maurizio Repetto |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 463 KB |
| Title: | DYNAMIC OPERATION OF COILS WITH FERROMAGNETIC CORES TAKING MAGNETIC HYSTERESIS INTO ACCOUNT |
| Abstract: | The computation of electromagnetic field diffusion in ferromagnetic and conductive media is coupled to circuit analysis problems, involving coils with iron cores. The classical Preisach model provides the relationship between magnetic field intensity and flux density at the local level, inside the core. Combined with a 2D eddy current simulation, carried out by a time stepping method, the dynamic operation of the core is modelled. The circuit equations are solved taking the effects of hysteresis and skin effects caused by eddy currents induced in core sheets into account. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 96-101] |
| Author(s): | Janos Fuzi, Janos Fuzi |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 433 KB |
| Title: | A STRONG COUPLING MODEL FOR THE SIMULATION OF MAGNETOMECHANICAL SYSTEMS USING A PREDICTOR/MULTI-CORRECTOR ALGORITHM |
| Abstract: | A recently developed modeling scheme for the numerical simulation of coupled magnetomechanical systems is presented. The scheme allows the calculation of dynamic rigid motions as well as deformations of magnetic and anti-magnetic materials in a magnetic field. The equations governing the magnetic and mechanical field quantities are solved using a combined Finite Element /Boundary-Element-Method (FEM-BEM). To circumvent the nonlinear system of equations resulting from a direct coupling of the magnetic and mechanical systems, the calculation of the magnetic forces is based on predictor values of the magnetic quantities. Therewith, a decoupling into a magnetic and mechanical matrix equation can be achieved. To ensure the strong coupling between the magnetic and mechanical quantities, a sophisticated Predictor/Multicorrector Algorithm is used resulting in an efficient iteration between the two matrix equations within a single time step. Computer simulations of an electromagnetic forming system and a magnetomechanical transducer immersed in an acoustic fluid (acoustic power source) show good agreement between simulation results and measured data. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 102-106] |
| Author(s): | M. Kaltenbacher, H. Landes, R. Lerch, M. Kaltenbacher, H. Landes, R. Lerch |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 347 KB |
| Title: | RESULTS OF PARALLELISATION OF EXISTING ELECTROMAGNETIC FINITE ELEMENT CODES ON SOME DIFFERENT PARALLEL ARCHITECTURES |
| Abstract: | In this paper the results obtained from the parallelisation of some 3D industrial electromagnetic Finite Element codes within the ESPRIT Europort 2 project PARTEL are presented. The basic guidelines for the parallelisation procedure, based on the Bulk Synchronous Parallel approach, are presented and the encouraging results obtained in terms of speed-up on some selected test cases of practical design significance are outlined and discussed. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 107-112] |
| Author(s): | M. Dracopoulos, K. Palrot, G. Molinari, M. Nervi, J. Simkin, M. Dracopoulos, K. Palrot, G. Molinari, M. Nervi, J. Simkin |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 617 KB |
| Title: | THE NEWTON-RAPHSON METHOD FOR COMPLEX EQUATION SYSTEMS |
| Abstract: | A formulation for the complex Newton-Raphson method is proposed. The derivation is obtained on the assumption of a non-analytical system. The method is applied to the finite element calculation of shielding problems with sinusoidal ex-citation and ferromagnetic material. An application example for which measurement data are available is given in order to judge the convergence characteristics and the reliability of the proposed method. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 113-116] |
| Author(s): | Dieter Lederer, Hajime Igarashi, Arnulf Kost, Dieter Lederer, Hajime Igarashi, Arnulf Kost |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 319 KB |
| Title: | SOME ASPECTS OF MAGNETIC FORCE COMPUTATION USING BEM-FEM COUPLING |
| Abstract: | For the calculation of magnetic forces with the Maxwell stress tensor the normal and the tangential derivatives of the vector potential A have to be known. We choose Co-continuous elements, therefore A and its tangential derivatives are continuous. In contrast, the normal derivative A/ n calculated with the finite element method is continuous only in a weak sense. When BEM-FEM coupling is used however, the value of A/ n is uniquely available on the coupling surfaces from the BEM formulation. Two methods of magnetic force computation using A/ n either from FEM or from BEM data will be presented. Their accuracy will be compared by means of several examples. [Vol. 12, No. 2 (1997), pp Special Issue on Numerical Field Calculations in Electrical Engineering, 117-120] |
| Author(s): | Joachim Fetzer, Stefan Kurz, Gunther Lehner, Wolfgang M. Rucker, Joachim Fetzer, Stefan Kurz, Gunther Lehner, Wolfgang M. Rucker |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 270 KB |
| Title: | THE NUMERICAL TREATMENT OF SINGULAR INTEGRALS IN BOUNDARY ELEMENT CALCULATIONS |
| Abstract: | In this paper a general method for the evaluation of singular boundary element integrals over three-dimensional isoparametric boundary elements of higher order is presented. This method permits an efficient integration of strongly singular kernels of order O(1/r2) and of nearly strong singular kernels on curved surfaces. For numerical examples the proposed integration scheme is compared with analytical test examples showing high efficiency and accuracy. This new method has full generality and, therefore, can be applied in any field of electromagnetics. The actual computation can be easily included in any existing computer code, e. g. for the solution of electromagnetic scattering problems. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 121-126] |
| Author(s): | C.J. Huber, W. Rieger. M. Haas, W.M. Rucker, C.J. Huber, W. Rieger. M. Haas, W.M. Rucker |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 416 KB |
| Title: | MODELLING EDDY CURRENTS INDUCED BY ROTATING SYSTEMS |
| Abstract: | As part of a Japanese funded project, a transient eddy current code is being extended to allow for rotational systems. By allowing the system to rotate, induced eddy currents must be modelled. The system being developed uses the "lock-step" approach to model the rotation. As other facilities are included (non-linear materials for example), the solution time of the final code becomes sufficiently large that special care must be taken, and investigations into using parallel hardware becomes necessary. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 131-134] |
| Author(s): | C. R. I. Emson, C. P. Riley, D. A. Walsh, C. R. I. Emson, C. P. Riley, D. A. Walsh |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 412 KB |
| Title: | BEM-FEM COUPLING IN ELECTROMECHANICS: A 2-D WATCH STEPPING MOTOR DRIVEN BY A THIN WIRE COIL |
| Abstract: | This paper deals with the transient numerical analysis of 2-d electromechanical devices driven by thin wire coils. Their dynamical behavior is described by the Maxwell equations, by the constitutive relations, and by the equations of motion. For the solution of the electromagnetic problem the BEM-FEM coupling method is used. A two- dimensional watch stepping motor is presented as an example. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 135-139] |
| Author(s): | Stefan Kurz, Joachim Fetzer, Thomas Kube, Gunther Lehner, Wolfgang M. Rucker, Stefan Kurz, Joachim Fetzer, Thomas Kube, Gunther Lehner, Wolfgang M. Rucker |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 389 KB |
| Title: | HYBRID FORMULATIONS FOR 3D MAGNETOSTATIC AND EDDY CURRENT PROBLEMS |
| Abstract: | Hybrid formulations for solving nonlinear 3D magnetostatic and eddy current problems in terms of magnetic field H are presented. In the pro- posed formulations integral operators are utilized as if the boundary conditions for a partial differential equation were solved within the system of equations. A good correspondence between the results of the presented methods and measurements or other methods is obtained for some test problems. [Vol. 12, No. 2 (1997), Special Issue on Numerical Field Calculations in Electrical Engineering, pp 140-144] |
| Author(s): | Kimmo Forsman, Lauri Kettunen, Kimmo Forsman, Lauri Kettunen |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 2 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 470 KB |
| Title: | DOMAIN DECOMPOSITION STRATEGIES FOR SOLVING THE MAXWELL EQUATIONS ON DISTRIBUTED PARALLEL ARCHITECTURES |
| Abstract: | Domain decomposition strategies for solving hyperbolic systems of partial differential equations on distributed-memory parallel computing platforms are investigated. The logically-rectangular computational domain is divided either one, two, or three dimensionally into a series of computational blocks, and each block is assigned to a single processor. Theoretical predictions using standard parallel performance models indicate that higher-dimensional decompositions provide superior parallel program performance in terms of scalability. The theory is tested using a finite-volume time-domain (FVTD) Maxwell equations solver to compute the electromagnetic fields inside a rectangular waveguide using various grid sizes and processor numbers on three different parallel architectures- the Intel Paragon, the IBM SP2, and the Cray T3D. The specific performance of the FVTD algorithm on the three machines is investigated, the relation between processor connection topology and message passing performance of a typical grid-based hyperbolic equation solver are identified, and the results are used to augment the classical parallel performance model. Although clear performance trends emerge in terms of the dimensionality of the decomposition, results indicate that higher-dimensional decompositions do not always provide superior parallel performance. [Vol. 12, No. 3 (1997), pp 4-15] |
| Author(s): | Douglas C. Blake, Thomas A. Buter, Douglas C. Blake, Thomas A. Buter |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 3 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 892 KB |
| Title: | MOMENT METHOD SURFACE PATCH AND WIRE GRID ACCURACY IN THE COMPUTATION OF NEAR FIELDS |
| Abstract: | The accuracy of surface patch and wire grid moment method models for the of near fields is investigated. A sphere and a flat plate with plane wave illumination are examined. It is found that wire grids exhibit stronger near field anomalies than surface patches, which have the current more distributed over the surface. Nevertheless, good results can be obtained with a wire grid, provided that a small distance from the wire grid surface is maintained The surface patch results are obtained using the Junction code. Wire grid results are with both the MBC and NEC codes. Validation the sphere is by comparison with an exact solution obtained from the NECBSC code. [Vol. 12, No. 3 (1997), pp 16-25] |
| Author(s): | Robert Paknys, Leslie R. Raschkowan, Robert Paknys, Leslie R. Raschkowan |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 3 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 578 KB |
| Title: | FINITE-DIFFERENCE TIME-DOMAIN MODELING OF LIGHT-TRAPPING IN SOLAR CELLS |
| Abstract: | To maximize light-trapping, the absorption of light in the solar cell is maximized. The ways to increase light-trapping are to texture the surfaces of the solar cell and to use anti-reflection coatings. The power spectrum of sunlight also plays an important role in light-trapping. In general, a solar cell consists of multiple layers of dielectric materials. Each dielectric has a complicated surface texture geometry to increase light-trapping. This paper concentrates on solving Maxwell's equations for the general solar cell configuration under illumination from the sun. The absorption and maximum achievable current density are calculated and used to quantify light-trapping in a given solar cell design. Thin solar cells promise to yield higher current collection than thick solar cells at a lower cost [1]. Low cost solar cells are usually characterized by short diffusion length semiconductors. Most minority carriers created within the distance equal to the diffusion length contribute to the electrical current of a solar cell. Hence, the solar cell must be thin when low quality materials are used. As solar cells decrease in size, the ray-trace model becomes inaccurate as previously demonstrated in [2]. A full-wave Finite-Difference Time-Domain (FDTD) light-trapping model is demonstrated to accurately study light-trapping of thin-film solar cells. [Vol. 12, No. 3 (1997), pp 31-42] |
| Author(s): | Todd Marshall, Melinda Piket-May, Todd Marshall, Melinda Piket-May |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 3 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 872 KB |
| Title: | MODELLING EDDY CURRENTS IN UNBOUNDED STRUCTURES USING THE IMPEDANCE METHOD |
| Abstract: | In this paper extensions to the impedance network method are presented. In particular the method has been applied to problems with boundaries extending to infinity. The infinite boundary condition can also be applied to lines of symmetry in the given geometry. Two dimensional surface models have been verified by comparison of numerical and experimental results in which the potential was measured along the edge of copper sheeting of various shapes located in a uniform, quasi-static magnetic field. The method has potential for modelling three dimensional structures including anisotropic earth planes, arbitrarily shaped buried objects, and both finite and infinitely long faults, dykes, pipes, cylinders and cracks. [Vol. 12, No. 3 (1997), pp 43-49] |
| Author(s): | Daniel James Daniel James, David V. Thiel, Daniel James Daniel James, David V. Thiel |
| File Type: | Journal Paper |
| Issue: | Volume: 12 Number: 3 Year: 1997 |
| Download Link: | Click here to download PDF File Size: 479 KB |
| Title: | CALCULATION OF ELECTROMAGNETIC SCATTERING VIA VARIATIONS AND ANALYTIC CONTINUATION |
| Abstract: | In this paper we review a numerical method we introduced recently for the solution of problems of electromagnetic scattering. Based on variations of the boundaries of the scatterers and analytic continuation, our approach yields algorithms which are applicable to a wide variety of scattering configurations. We discuss some recent applications of this method to scattering by diffraction gratings and by large two-dimensional bounded bodies, and we present results of new applications to three-dimensional gratings containing corners and edges. In many cases of practical interest our algorithms give nu- merical results which are several orders of magnitude more accurate than those given by classical methods. [Vol. 11, No. 1 (1996), pp 17- 31, Special issue on Applied Mathematics: Meeting the challenges presented by computational electromagnetics] |
| Author(s): | Oscar P. Bruno, Fernando Reitich, Oscar P. Bruno, Fernando Reitich |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 1 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 1314 KB |
| Title: | ERROR CONTROL IN NUMERICAL SOLUTIONS OF BOUNDARY INTEGRAL EQUATIONS |
| Abstract: | A method of estimating the error committed in numerical solutions of integral equations is presented. It is shown how the error can be computed in spaces other than L^2, why this is reasonable and sometimes necessary. The appropriate function spaces are also shown to lead to bounded condition numbers even for first kind equations. [Vol. 11, No. 1 (1996), pp 32-36, Special issue on Applied Mathematics: Meeting the challenges presented by computational electromagnetics] |
| Author(s): | G . C . HSIAO, R. E . R. E . KLEINMAN, G . C . HSIAO, R. E . R. E . KLEINMAN |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 1 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 386 KB |
| Title: | CALCULATIONS IN MATHEMATICA ON LOW-FREQUENCY DIFFRACTION BY A CIRCULAR DISK |
| Abstract: | This paper is devoted to the symbolic calculation of the scattering coefficient in diffraction by a circular disk, by the use of Mathematica. Three diffraction problems are considered: scalar diffraction by an acoustically soft disk, scalar diffraction by an acoustically hard disk, and electromagnetic diffraction by a perfectly conducting disk. In the low-frequency approximation, the solutions of these problems are in the form of expansions in powers of ka, where a is the radius of the disk and k is the wave number. The emphasis is on the low-frequency expansion for the scattering coefficient, of which several terms are determined exactly with the help of Mathematica. [Vol. 11, No. 1 (1996), pp 47-56, Special issue on Applied Mathematics: Meeting the challenges presented by computational electromagnetics] |
| Author(s): | J. Boersma, M. J. H. Anthonissen, J. Boersma, M. J. H. Anthonissen |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 1 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 597 KB |
| Title: | SCATTERING BY LARGE STRUCTURES WITH PERIODIC SURFACES: A PROTOTYPE PROBLEM |
| Abstract: | A hybrid method which uses both numerical and asymptotic techniques is described and applied to the scattering of an electromagnetic wave off a large corrugated circular cylinder. The radius of the cylinder is large compared to the wavelength of the incident radiation, but the corrugation height and period are of the same order as the wavelength. This problem is a prototype of a more general situation where the surface of a target is covered with a periodic coating. The method of attack essentially blends boundary layer theory, which describes the local scattering behavior of the surface, and the theory of geometrical optics which gives a global description of the scattering. Although the hybrid method is only developed here for this simple model, its applicability for other targets is clear. [Vol. 11, No. 1 (1996), pp 57-62, Special issue on Applied Mathematics: Meeting the challenges presented by computational electromagnetics] |
| Author(s): | G.A. Kriegsmann, G.A. Kriegsmann |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 1 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 428 KB |
| Title: | MONO-STATIC RCS COMPUTATION WITH A BLOCK GMRES ITERATIVE SOLVER |
| Abstract: | We present a new method of computing mono-static radar cross sections using a preconditioned Block GMRES iterative algorithm. The convergence properties of this algorithm are analyzed using RCS error, equation residual error and solution error. It is found that this method is nearly an order of magnitude faster than direct methods (LINPACK) for realistic method of moment problems. [Vol. 11, No. 1 (1996), pp 63-69, Special issue on Applied Mathematics: Meeting the challenges presented by computational electromagnetics] |
| Author(s): | William E. Boyse, Andrew A. Seidl, William E. Boyse, Andrew A. Seidl |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 1 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 617 KB |
| Title: | MODERN KRYLOV SUBSPACE METHODS IN ELECTROMAGNETIC FIELD COMPUTATION USING THE FINITE INTEGRATION THEORY |
| Abstract: | A theoretical basis for numerical electromagnetics, the so-called Finite Integration Theory, is described. Based upon Maxwell's equations in their integral form, it results in a set of matrix equations, each of which is a discrete analogue of its original analytical equation. Applications of this discretization process are described here in the context of the numerical simulation of electroquasistatic problems and of time-harmonic field computations including a new type of waveguide boundary condition, which is presented here for the first time. In both fields the process of mathematical modelling and discretization yields large systems of complex linear equations which have to be solved numerically. For this task several modern Krylov subspace methods are presented such as BiCG, CGS and their more recent stabilized variants CGS2, BiCGSTAB(I) and TFQMR. They are applied in connection with efficient preconditioning methods. The applicability of these modern methods is shown for a number of examples for both problem types. [Vol. 11, No. 1 (1996), pp 70-84, Special issue on Applied Mathematics: Meeting the challenges presented by computational electromagnetics] |
| Author(s): | Markus Clemens, Rolf Schuhmann, Ursula van Rienen, Thomas Weiland, Markus Clemens, Rolf Schuhmann, Ursula van Rienen, Thomas Weiland |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 1 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 1195 KB |
| Title: | FINITE DIFFERENCE METHODS FOR THE NONLINEAR EQUATIONS OF PERTURBED GEOMETRICAL OPTICS |
| Abstract: | Finite difference methods are developed to solve the nonlinear partial differential equations approximating solutions of the Helmholtz equation in high frequency regime. Numerical methods are developed for solving the geometrical optics approximation, the classical asymptotic expansion, and a new perturbed geometrical optics system. We propose a perturbed geometrical optics system to recover diffraction phenomena that are lost in geometrical optics approximations. We discuss techniques we have developed for recovering multivalued solutions and we present numerical examples computed with finite difference approximations of the above systems. [Vol. 11, No. 1 (1996), pp 90-98, Special issue on Applied Mathematics: Meeting the challenges presented by computational electromagnetics] |
| Author(s): | E. Fatemi, B. Engquist, and S. Osher, E. Fatemi, B. Engquist, and S. Osher |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 1 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 661 KB |
| Title: | ANALYSIS OF THE FINITE ELEMENT RADIATION MODEL CODE FOR ANTENNA MODELING |
| Abstract: | The Finite Element Radiation Model (FERM) code is applied to examine radiation patterns and input impedance of various antenna con- figurations on complex helicopters. This paper addresses the strengths and weaknesses of the FERM code when applied in antenna analysis and is compared with other national codes, such as the Numerical Electromagnetics Code (NEC). In addition, guidelines are outlined for various applications of the code. [Vol. 11, No. 2 (1996), pp 4-13] |
| Author(s): | Marcos C. Medina, Constantine A. Balanis, Jian Peng, Panayiotis A. Tirkc Panayiotis A. Tirkc, Marcos C. Medina, Constantine A. Balanis, Jian Peng, Panayiotis A. Tirkc Panayiotis A. Tirkc |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 2 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 702 KB |
| Title: | ACCURACY OF THE FINITE ELEMENT METHOD WITH SECOND ORDER ABSORBING BOUNDARY CONDITIONS FOR THE SOLUTION OF APERTURE RADIATION PROBLEM |
| Abstract: | The Finite Element Method with second order Absorbing Boundary Condition is a recently developed computational technique that finds use in antenna design and Electromagnetic Compatibility simulation. To determine the accuracy of this new procedure, the problem of aperture radiation was studied. The near zone and aperture fields of a waveguide antenna computed using the Finite Element Method are compared with published data and results found using other simulation techniques. These comparisons show that the new method is accurate even when the ABC boundary conforms to the problem geometry and is placed as near as /2pi to the aperture. [Vol. 11, No. 2 (1996), pp 14-23] |
| Author(s): | John Silvestro, Xingchao Yuan, Zoltan Cendes, John Silvestro, Xingchao Yuan, Zoltan Cendes |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 2 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 580 KB |
| Title: | A MOMENT METHOD FORMULATION FOR THE ANALYSIS OF WIRE ANTENNAS ATTACHED TO ARBITRARY CONDUCTING BODIES DEFINED BY PARAMETRlC SURFACE |
| Abstract: | A Moment Method (MM) technique for the analysis of wire antennas on board resonant-sized bodies modelled with parametric surfaces is presented. The approach may have useful applications for the study of the behaviour of wire antennas on board complex conducting structures like aircrafts. The current is represented by curved rooftop functions on the body, piecewise linear functions on the wires and a new junction function in the attachment region between the body and the antenna. The bodies are precisely defined by means of a small number of NURBS surfaces (Non Uniform Rational B-Splines) and Bezier patches (BP). In addition the new junction function that can be defined over any BP allows the antenna to be attached to any part of the body. Radiation patterns and input impedance calculations for several geometries are presented to show the accuracy of the method. The results are successfully validated when comparisons with measurements or results from other methods are carried out. [Vol. 11, No. 2 (1996), pp 32-39 |
| Author(s): | F. Rivas, L. Valle, M.F. Catedra, F. Rivas, L. Valle, M.F. Catedra |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 2 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 534 KB |
| Title: | A POSTERIORI ERROR ESTIMATES FOR TWO-DIMENSIONAL ELECTROMAGNETIC FIELD COMPUTATIONS: BOUNDARY ELEMENTS AND FINITE ELEMENTS |
| Abstract: | A brief summary of the variational boundary-value problem formulation of the 2D finite element/boundary element (FE/BE) method is presented. >From this a posteriori error estimates and error indicators for the FE/BE method are developed and applied to electromagnetic scattering and radiation problems. The results obtained indicate that these error estimates and indicators can be obtained within negligible computational times and can be used successfully to obtain valuable a posteriori accuracy and convergence information regarding the reliability of the FE/BE method solutions. [Vol. 11, No. 2 (1996), pp 40-54] |
| Author(s): | F.J.C. Meyer, D.B. Davidson, F.J.C. Meyer, D.B. Davidson |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 2 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 1233 KB |
| Title: | MODELLING OF AN ARBITRARILY-ORIENTED MOBILE TELEPHONE HANDSET IN THE FINITE-DIFFERENCE TIME-DOMAIN FIELD COMPUTATION METHOD |
| Abstract: | The implementation of a generic mobile telephone handset model in the Finite Difference Time Domain (FDTD) method for computation of electromagnetic field distributions is described. The handset can be rotated about the principal FDTD axes to achieve any orientation. The 'thin wire' technique is used to model the antenna in a way that ensures that its correct electrical length is maintained despite the 'staircasing' effect of the FDTD grid. Computed predictions from the model agree with near-field measurements on a physical realisation of the handset, and accurate near and far fields are calculated for arbitrary orientations of the handset. It is concluded that this wire rotation technique has broad application to problems involving components that are required to move in relation to fixed structures. [Vol. 11, No. 2 (1996), pp 55-65] |
| Author(s): | P.S. Excell, P. Olley, N.N. Jackson, P.S. Excell, P. Olley, N.N. Jackson |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 2 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 886 KB |
| Title: | A MAGNETIC FIELD ITERATIVE TECHNIQUE FOR IMPROVING HIGH FREQUENCY PREDICTION METHODS |
| Abstract: | A Magnetic Field Iterative Technique (MFIT) is developed as a technique for improving the results from high frequency based prediction methods. The technique combines the accuracy of low frequency methods with the speed of high frequency methods to develop a contraction mapping based, iterative solver, which is directly parallelizable on current massively parallel processing machines. In this paper, the MFIT is developed from a Magnetic Field Integral Equation (MFIE) and its contraction discussed. Results obtained mapping properties are using the technique and convergence properties are three dimensional perfect illustrations of the technique's presented for both two and electrically conducting (PEC) targets. [Vol. 11, No. 2 (1996), pp 66-71] |
| Author(s): | Daniel D. Reuster, Gary A. Thiele, Paul W. Eloe, Daniel D. Reuster, Gary A. Thiele, Paul W. Eloe |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 2 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 1171 KB |
| Title: | MODELING OF REMOTE FIELD EDDY CURRENT TRANSIENT PHENOMENA |
| Abstract: | An integral formulation is presented and used for the analysis of the Remote Field Eddy Current (RFEC) transient phenomena. The model presented allows simple and accurate modeling of RFEC systems in the presence of axisymmetric defects. The method has been validated first by comparison of the computed results with results obtained with an analytical model. Then the method was used to show that the Remote Field effect is mainly due to a direct induction effect rather than propagation effects. The Remote Field effect phenomena are usually analysed using a steady state domain. However, the results obtained here have shown that detection of defects is not due to a steady state phenomenon, but depends mainly on the transient signal. [Vol. 11, No. 2 (1996), pp 72- 75] |
| Author(s): | M. Raugi, N. Ida, M. Raugi, N. Ida |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 2 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 297 KB |
| Title: | SOLUTION OF LAPLACE'S EQUATION USING MULTIPLE PATHS METHOD (MPM) |
| Abstract: | A probabilistic method called the multiple paths method (MPM) is presented to solve the potential equation. Unlike other probabilistic techniques there is no need for the generation of a grid resulting in less computation time and simplicity. The method is based on the calculation of the probability of absorption of a particle at a point on the boundary. The random walk is along a "path" which is a line passing through the starting point, where the potential is to be determined. The results show good agreement with other probabilistic methods and numerical techniques. [Vol. 11, No. 3 (1996), pp 4-8 |
| Author(s): | J. Rashed-Mohasselel, M. Fasih, J. Rashed-Mohasselel, M. Fasih |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 3 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 349 KB |
| Title: | A NEW DESIGN METHOD FOR LOW SIDELOBE LEVEL LOG-PERIODIC DIPOLE ANTENNAS |
| Abstract: | A new design procedure for log-periodic dipole arrays is presented in this paper. In this method, either the scale factor or the number of dipole elements is selected, after the boom length, and the operating frequency region are specified. The procedure is applied iteratively, in conjunction to the Numerical Electromagnetic Code, to produce a design with low sidelobe levels. With this new procedure, the antenna designer has more control over the boom length; in older techniques, the boom length and the element spacing were dependent on previous calculations, which frequently resulted on unreasonable values Results for several designs are presented, showing the peak gain to peak-sidelobe level ratio, and the antenna gain as a function of frequency, for different scale factors and boom lengths, for a frequency range of 13 to 30 MHz. [Vol. 11, No. 3 (1996), pp 9-15] |
| Author(s): | James K. Breakall, Rafael A. Rodriguez Solis, James K. Breakall, Rafael A. Rodriguez Solis |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 3 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 445 KB |
| Title: | NUMERICAL EVALUATION OF SINGULAR INTEGRANDS IN THE APPLICATION OF THE CHARGE SIMULATION METHOD WITH DISTRIBUTED CHARGE DENSITY |
| Abstract: | As it is well known the Charge Simulation Method is a numerical method for the computation of the electric field in three-dimensional problems, based on the concept of the substitution of the electrodic geometry with a series of elementary charge suitably arranged. In this paper we will show a possible, useful way to overpass the difficulties arising in the numerical computations on the integral expression of the electric potential in the contour points where the boundary conditions are imposed, when distributed surface charges are used in the simulation. The numerical approach presented here allows us to evaluate with accuracy the potential coefficients on the metallic surfaces, avoiding the presence of oscillatory numerical solutions in the computation of the electric potential and of the electric field strength around the electrodes, that generally occurs when discrete charges are used in the simulation. [Vol. 11, No. 3 (1996), pp 16-24] |
| Author(s): | Ermanno Cardelli, Loris Faina, Ermanno Cardelli, Loris Faina |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 3 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 482 KB |
| Title: | MEASURED RCS POLAR CONTOUR MAPS FOR CODE VALIDATION |
| Abstract: | Measured radar cross-section (RCS) data as a function of the angle of incidence and of the frequency over a wide range provide an excellent basis for code validation. This paper examines the RCS of six targets measured as a function of the angle of incidence of the plane wave, and of the frequency, through and beyond the resonance range of target size. The RCS is presented as a function of frequency and incidence angle using a color contour map in a polar format, with the radius proportional to the frequency. Such polar contour maps exhibit striking patterns to the underlying scattering mechanisms and target geometry. The RCS as a function of incidence angle and frequency is available from the authors for an extensive collection of targets. [Vol. 11, No. 3 (1996), pp 25-43] |
| Author(s): | C.L. Larose, C.W. Trueman, C.L. Larose, C.W. Trueman |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 3 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 2808 KB |
| Title: | AN EFFICIENT METHOD OF ANALYSIS OF CO-PLANAR DIPOLE ARRAY ANTENNAS |
| Abstract: | Generalized impedance formulas for non-uniform array configurations based on the improved Circuit Theory (ICT) are presented for the first time in an English text. To further enhance the ICT as an accurate and fast method for evaluations, a new and more com pact closed-form formula is derived to replace a function requiring time intensive numerical integration during the implementation of the of the ICT algorithm in co-planar dipole array antenna evaluations. The resulting ICT computational scheme reduces the required CPU time by a factor of two and has the same order of accuracy as the conventional MoM. The new ICT implementation would be of considerable use as a Computer Aided Design (CAD) tool of co-planar dipole array antennas. [Vol. 11, No. 3 (1996), pp 44-54] |
| Author(s): | A. I. Imoro, N. Inagaki, N. Kikuma, A. I. Imoro, N. Inagaki, N. Kikuma |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 3 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 848 KB |
| Title: | AN ALGORITHM FOR SOLUTION OF THE INVERSE ELECTROMAGNETIC LIQUID METAL CONFINEMENT PROBLEM |
| Abstract: | The design of an electromagnetic levitation system for large amounts of liquid metal requires the solution of an inverse field problem. The objective is to calculate the electromagnetic pressure distribution which corresponds to a specific metallo-static head. This paper describes an algorithm for the design of coil systems which will produce the desired pressure distribution. The technique is illustrated by the design of a torroidal levitation system. [Vol. 11, No. 3 (1996), pp 55-62] |
| Author(s): | G.J. Bendzsak, G.J. Bendzsak |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 3 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 687 KB |
| Title: | COMPARISON OF MAGNETICALLY INDUCED ELF FIELDS IN HUMANS COMPUTED BY FDTD AND SCALAR POTENTIAL FD CODES |
| Abstract: | This paper presents a detailed numerical comparison of the magnetically-induced extremely low-frequency electric field and current density within an anatomically realistic model of the full human body, as computed using two different numerical techniques. The first technique is a recently-described full-wave quasi-static finite-difference time-domain (FDTD) method. The use of a time-ramped excitation involving pairs of oppositely-directed plane waves allows for the calculation of decoupled magnetic and electric induction in complex heterogeneous bodies, in relatively short (5 ns) simulation times. The second method is an implementation of Stevenson's method applied for isolated conducting bodies. With the lowest-order external magnetic field represented by a vector potential, the lowest-order internal electric field can be represented by a scalar conduction potential, and the magnetically-induced contribution can be calculated in isolation. Both methods have an underlying similarity in their finite-difference approach, but are nevertheless very distinct. Each code was used to calculate the fields, induced by three orthogonal uniform magnetic fields, in a 7.2 mm-resolution human full-body model. Three-dimensional correlation coefficients of better than 99.9998% were observed between current densities computed by the two methods. Individual edge electric fields typically agree to 3 significant digits. [Vol. 11, No. 3 (1996), pp 63-71] |
| Author(s): | Trevor W. Dawson, Jan De Moerloose, Maria A. Stuchly, Trevor W. Dawson, Jan De Moerloose, Maria A. Stuchly |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 3 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 693 KB |
| Title: | ANALYTIC VALIDATION OF A THREE-DIMENSIONAL SOLAR-POTENTIAL FINITE- DIFFERENCE CODE FOR LOW-FREQUENCY MAGNETIC INDUCTION |
| Abstract: | This paper presents a detailed comparison of numerical and analytical calculations of the low-frequency electric and current density fields, induced by an applied uniform axial magnetic field, in an equatorially stratified sphere having the conductivity distribution Rho (_)=Rho0e- cos( _) with p {1,2} and > 0. As shown by the analytic solution, the resulting induced fields are fully three-dimensional, and the model therefore serves as a rigorous test of numerical codes The numerical method is a scalar-potential finite-difference scheme based on Stevenson's method for isolated conducting bodies. This computer code was recently shown to provide excellent agreement with results computed independently by a modified Finite-Difference Time-Domain method. Nevertheless, both codes share some underlying similarities, such as their common use of parallelepiped material voxels to represent the conductivity distribution, and of an edge-based staggered to model the electric fields. Therefore, it is of value to compare the numerical results with analytic ones The analytic model has a freely adjustable contrast parameter, and supports both pi and 2pi-periodic conductivity distributions. Numerical and analytical results are compared for several configurations. Full three-dimensional volumetric correlation coefficients are typically of the order of 99% or better. As might be expected, the main differences occur at the surface of the sphere, where the true circumferential fields are most poorly approximated by the staircasing approximation inherent the numerical approximation. [Vol. 11, No. 3 (1996), pp 72-81] |
| Author(s): | Trevor W. Dawson, Maria A. Stuchly, Trevor W. Dawson, Maria A. Stuchly |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 3 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 767 KB |
| Title: | THE GRADIENT ASSOCIATED CONJUGATE DIRECTION METHOD |
| Abstract: | A new conjugate direction (CD) based method, GaCD by name, is addressed with its full derivations. Comparison with some commonly used CD methods is made, concluding that the GaCD method is among the best of them, in terms of an assessment number. A practical example is presented in which a waveguide-microstrip transition section is optimized with respect to its transmission parameter S2l. The measurement of the transition agrees very well with the numerical results. [Vol. 11, No. 3 (1996), pp 82-96] |
| Author(s): | Min Zhang, Min Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 3 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 1873 KB |
| Title: | THE NEC2 RADIATION PATTERNS OF UNDER-SEGMENTED WIRE GRID MODELS OF A FIGHTER AIRCRAFT COMPARED TO MEASUREMENTS |
| Abstract: | This paper presents results of a NEC2 method of moments evaluation of VHF/UHF antennas on a wire grid model of a fighter aircraft. The study shows that practically useful radiation patterns results can be obtained when the grid model is considerably under-segmented in aircraft regions which are electrically far removed from the antennas. Normal modelling guide-lines requires approximately 35000 segments for the fighter grid model at 400 MHz; judicious under-segmentation gave useful results using a model comprising 5000 segments. This reduction in segments reduced computer time by a factor of 343 and memory requirements is reduced by a factor of 18. NEC2 radiation patterns are compared to measurements on a l/lOth scale model which was performed in an anechoic chamber compact range. [Vol. 10, No. 1 (1995), pp 5-14] |
| Author(s): | 0. Givati, A.P.C. Fourie, 0. Givati, A.P.C. Fourie |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 1 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 667 KB |
| Title: | A SURFACE INTEGRAL EQUATION FORMULATION FOR LOW CONTRAST SCATTERERS BASED ON RADIATION CURRENTS |
| Abstract: | A new surface integral equation formulation based on radiation currents is presented. Numerical problems have been observed when treating low contrast scatterers with surface integral equation formulations based on the total equivalent currents. These problems result because the total equivalent currents are large compared with the radiation currents for low contrast materials. The surface integral equation formulation presented here avoids this problem by solving directly for the radiation currents. [Vol. 10, No. 1 (1995), pp 15-18] |
| Author(s): | Paul M. Goggans, Allen W. Glisson, Paul M. Goggans, Allen W. Glisson |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 1 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 423 KB |
| Title: | THE MEASURED EQUATION OF INVARIANCE METHOD APPLIED TO RANDOMLY ROUGH SURFACES |
| Abstract: | The Measured Equation of Invariance (MEI) method has received considerable attention recently. Unlike more traditional numerical techniques, MEI solutions are obtained by inversion of a relatively small and sparse matrix. Therefore, the MEI method can potentially provide a solution much more quickly than other techniques. To date, the MEI method has been applied primarily to discrete objects. In this paper, bistatic radar cross sections for one-dimensional, perfectly conducting, randomly rough surfaces are obtained using the MEI method. The implementation suitable for this problem requires some modification and enhancement of the original algorithm to achieve the desired accuracy. These algorithmic changes can be applied to the discrete scattering problem as well. Monte Carlo results for the bistatic scattering cross section for surfaces with Gaussian statistics and satisfying a Gaussian roughness spectrum are compared to those from another technique and excellent agreement is obtained. [Vol. 10, No. 1 (1995), pp 19-30] |
| Author(s): | John B. Schneider, Shira Lynn Broschat, John B. Schneider, Shira Lynn Broschat |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 1 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 1519 KB |
| Title: | A GUIDE TO IMPLEMENTATIONAL ASPECTS OF THE SPATIAL DOMAIN INTEGRAL EQUATION ANALYSIS OF MICROSTRIP ANTENNAS |
| Abstract: | In the analysis of microstrip radiating structures integral equation methods rate among the more accurate approaches. By far the most demanding part in the use of these methods is the actual numerical implementation. This paper presents a detailed illustrated description of the numerical implementation of a spatial domain mixed-potential integral equation analysis of microstrip radiating structures. [Vol. 10, No. 1 (1995), pp 40-51] |
| Author(s): | Louis T. Hildebrand, Derek A. McNamara, Louis T. Hildebrand, Derek A. McNamara |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 1 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 1533 KB |
| Title: | PERFORMANCE OF A CHARACTERISTIC-BASED, 3-D, TIME-DOMAIN MAXWELL EQUATIONS SOLVER ON THE INTEL TOUCHSTONE DELTA |
| Abstract: | A characteristic-based, windward numerical procedure for solving three-dimensional Maxwell equations in the time domain has been successfully ported to the Intel Touchstone Delta multicomputer. The numerical results by concurrent computation duplicated the earlier simulations of an oscillating electric dipole on a vector processor and compared well with the exact solutions. The parallelized code is scalable up to 512 nodes and incurs only up to 7.6% performance degradation. The sustained data processing rate is clocked at 6.551 Gigaops. However, the data I/O process is unscalable on the shared memory system. [Vol. 10, No. 1 (1995), pp 52-62] |
| Author(s): | J. S. Shang, Kueichien C. Hill, Donald A. Calahan, J. S. Shang, Kueichien C. Hill, Donald A. Calahan |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 1 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 1094 KB |
| Title: | ON THE APPLICABILITY OF THE BICONJUGATE GRADIENT FFT METHOD FOR THE THIN CONDUCTING PLATE PROBLEM |
| Abstract: | The application of the Biconjugate Gradient FFT method to the thin conducting plate problem is investigated. Upon comparing with a Conjugate Gradient FFT method, it is found that the Biconjugate Gradient solution requires a relatively larger error tolerance to achieve a comparatively well-behaved current distribution. Coupled with the requirement of only one matrix-vector product per iteration, the computational cost of the Biconjugate Gradient method is, thus, much smaller than those previously reported in the literature. Of particular importance is the use of the incident electric field as a starting estimate to alleviate the non-convergence behaviour which is usually associated with the application of a Biconjugate Gradient approach to conducting plates at grazing angle. For other angles of incidence, it is shown that this procedure also accelerates the resulting convergence rates as compared to those obtained by simply using zero as an initial estimate. [Vol. 10, No. 1 (1995), pp 63-68] |
| Author(s): | T. V. TRAN, A. McCOWEN, T. V. TRAN, A. McCOWEN |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 1 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 702 KB |
| Title: | REVISED INTEGRATION METHODS IN A GALERKIN BOR PROCEDURE |
| Abstract: | Several relatively simple numerical changes improve the speed and accuracy of the early Mautz and Harrington discretization procedure for boundary element method calculations of scattering from axially symmetric bodies. This method is still in common use in programs such as CICERO and GRMBOR. For a fixed set of geometry points, changes in the azimuthal (o) integration reduce computer time, especially when lossy materials are involved. Changes in the integration along the generating curve (t) improve accuracy. The most interesting of these is the use of the equal area rule from parallel wire modeling of solid surfaces to answer the old question of the optimal constant for dealing with an integrable singularity in some of the t integrals. Some of these changes are applicable to a variety of integral equations and boundary conditions. Most of them can be implemented with little programming effort. Tests are shown for difficult cases involving spheres, and Mie series calculations are used for comparison. [Vol. 10, No. 2 (1995), pp 5-16] |
| Author(s): | David R. Ingham, David R. Ingham |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 2 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 886 KB |
| Title: | HIGHER-ORDER FDTD METHODS FOR LARGE PROBLEMS |
| Abstract: | The Finite-Difference Time-Domain (FDTD) algorithm provides a simple and efficient means of solving Maxwell's equations for a wide variety of problems. In Yee's uniform grid FDTD algorithm the derivatives in Maxwell's curl equations are replaced by central difference approximations. Unfortunately, numerical dispersion and grid anisotropy are inherent to FDTD methods. For large computational domains, e.g., ones that have at least one dimension forty wavelengths or larger, phase errors from dispersion and grid anisotropy in the Yee algorithm (YA) can be significant unless a small spatial discretization is used. For such problems, the amount of data that must be stored and calculated at each iteration can lead to prohibitive memory requirements and high computational cost. To decrease the expense of FDTD simulations for large scattering problems two higher-order methods have been derived and are reported here. One method is second-order in time and fourth-order in space (2-4); the other is second-order in time and sixth-order in space (2-6). Both methods decrease grid anisotropy and have less dispersion than the YA at a set discretization. Also, both permit a coarser discretization than the YA for a given error bound. To compare the accuracy of the YA and higher-order methods both transient and CW simulations have been performed at a set discretization. In general, it has been found that the higher-order methods are more accurate than the YA due to the reduced grid anisotropy and dispersion. However, the higher-order methods are not as accurate as the YA for the simulation of surface waves. This is attributed to the larger spatial stencil used in calculating the fields for the higher-order methods. More research is needed to examine the accuracy of higher-order methods at material boundaries. [Vol. 10, No. 2 (1995), pp 17-29] |
| Author(s): | Charles W. Manry Jr, Shira L. Broschat, John B. Schneider, Charles W. Manry Jr, Shira L. Broschat, John B. Schneider |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 2 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 1102 KB |
| Title: | RADAR CROSS SECTION OF A RECTANGULAR CAVITY- A MASSIVELY PARALLEL CALCULATION |
| Abstract: | A sequential code that calculates the radar cross section of a rectangular waveguide cavity was modified to execute on a MasPar MP-l massively parallel computer with a SIMD architecture. The code uses the mode matching method of analysis to produce a set of matrix equations. Steps taken to accomplish the parallelization are discussed and some specific examples of program modification are presented. Timing results for wideband data are given that demonstrate the power of parallel computers for this type of application. Suggestions are made for further improvements as increased memory space becomes available. [Vol. 10, No. 2 (1995), pp 30-45] |
| Author(s): | L. D. Vann, L.T. Willet, J.S. Bagby, H.F. Helmken, L. D. Vann, L.T. Willet, J.S. Bagby, H.F. Helmken |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 2 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 835 KB |
| Title: | A NUMERICAL TECHNIQUE TO DETERMINE ANTENNA PHASE CENTER LOCATION FROM COMPUTED OR MEASURED PHASE DATA |
| Abstract: | In many antenna applications, it is a requirement to have knowledge of the antenna phase center properties. Many interpretations of antenna phase center and its apparent location exist. This paper will present a formulation for determination of antenna phase center location derived using the antenna phase response. A fortran program, developed from the formulations, is used to calculate phase center location for several examples which include both computed and simulated measured phase data. A simple numerical technique is presented that processes measured phase data allowing accurate phase center determination. [Vol. 10, No. 2 (1995), pp 46-62] |
| Author(s): | Steven R. Best, James M. Tranquilla, Steven R. Best, James M. Tranquilla |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 2 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 1044 KB |
| Title: | CONFORMAL ARRAY DESIGN SOFTWARE |
| Abstract: | A powerful conformal array design computer program can be developed by modification of a physical optics based array fed reflector analysis computer program. [Vol. 10, No. 2 (1995), pp 63-74] |
| Author(s): | H.K. Schuman, H.K. Schuman |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 2 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 556 KB |
| Title: | COMPARISON OF THE INPUT IMPEDANCE OF MONOPOLE ANTENNAS OBTAINED BY NEC, MINlNEC, AND MEASUREMENTS |
| Abstract: | This paper compares the input impedance of monopole antennas numerically calculated by NEC and MININEC with experimental results. This comparison determines the limitation of these two computer codes used for modeling more complicated structures. Two groups of monopoles are considered. The first group consists of eight electrically thin monopoles of length .28 meters (.235 wavelengths at 252 MHz) and radii of .4064, . 7874, 1.168, 1.562, 2.390, 3.162, 6.350, and 7.920 millimeters (.341E-3, .661E-3, .981E-3, 1.31E-3, 2.01E-3, 2.66E-3, 5.33E-3, and 6.65E-3 wavelengths at 252 MHz). For this group, impedance calculations were compared to measurements over the band of 237-267 MHz. The second group consists of five electrically thick monopoles of length .2 wavelengths and radii of .0509, .0635, .0847, .1129, and .1270 wavelengths. For the second group impedance calculations were compared with measurements of tubular monopoles with flat ends. The results of this paper show that the extended kernel option of NEC predicted measured monopole impedance measurements more accurately than MININEC. [Vol. 10, No. 2 (1995), pp 75-85] |
| Author(s): | R. J. Bauerle, J. K. Breakall, R. J. Bauerle, J. K. Breakall |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 2 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 745 KB |
| Title: | ACCURATE MODELING OF STEPPED-RADII ANTENNAS |
| Abstract: | The LP8, eight element, log periodic antenna made by M2 Enterprises has recently been modeled at Penn State University using both Version 2 and 4 of the Numerical Electromagnetics Code (NEC). The antenna has a steppedradii element construction and operates from 10 to 30 MHz. The stepped-radii element construction is difficult to model using NEC Version 2. To model a stepped-radii antenna with this version, equivalent lengths of constant radii are calculated using another method of moments program called ELNEC. These equivalent lengths replaced the original stepped radii elements of the log periodic antenna during the modeling. Fortunately, NEC Version 4 can simulate the stepped-radii elements directly, which makes the modeling procedure much easier and accurate. Both NEC models show good agreement with the measurements when compared to VSWR measurements. The authors hope that this paper will help others with similar modeling problems who cannot yet obtain NEC Version 4. [Vol. 10, No. 2 (1995), pp 86-95] |
| Author(s): | A. I. Bauerle, J. K. Breakall, A. I. Bauerle, J. K. Breakall |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 2 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 726 KB |
| Title: | MUTUAL VALIDATION OF THREE PROGRAMS FOR NUMERIC ANTENNA COMPUTATIONS |
| Abstract: | The numerical results obtained by three different codes, GALNEC, WARAN and NEC-2 are compared for thin dipoles and thick ones with hemispherical end caps and for arrays of such collinear dipoles. The electric field integral equation and Galerkin's method are used in the code GALNEC where solid thick dipole bodies are implemented. Mei's (1965) integral equation and collocation technique are wed in the code WARAN, where thick dipoles are simulated as arrays of thin wires. Good agreement has been obtained for current distri- butions and input and mutual impedances. [Vol. 10, No. 2 (1995), pp 96-101] |
| Author(s): | Andrew A. Efanov, Harald Schopf, Bernhard Schnizer, Andrew A. Efanov, Harald Schopf, Bernhard Schnizer |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 2 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 421 KB |
| Title: | Using GPUs for Accelerating Electromagnetic Simulations |
| Abstract: | The computational power and memory bandwidth of graphics processing units (GPUs) have turned them into attractive platforms for general-purpose applications at significant speed gains versus their CPU counterparts [1]. In addition, an increasing number of today's state-ofthe- art supercomputers include commodity GPUs to bring us unprecedented levels of performance in terms of raw GFLOPS and GFLOPS/cost. Inspired by the latest trends and developments in GPUs, we propose a new paradigm for implementing on GPUs some of the major aspects of electromagnetic simulations, a domain traditionally used as a benchmark to run codes in some of the most expensive and powerful supercomputers worldwide. After reviewing related achievements and ongoing projects, we provide a guideline to exploit SIMD parallelism and high memory bandwidth using the CUDA programming model and hardware architecture offered by Nvidia graphics cards at an affordable cost. As a result, performance gains of several orders of magnitude can be attained versus threadlevel methods like pthreads used to run those simulations on emerging multicore architectures |
| Author(s): | M. Ujaldon |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 4 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 309 KB |
| Title: | Unconditionally Stable Locally One-Dimensional FDTD Methods for Efficient Electromagnetic Simulations |
| File Type: | Conference Paper |
| Issue: | Volume: Optoelectronic modeling Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 77 KB |
| Title: | Tuning Space Mapping for Microwave Design Optimization |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Simulations using Sonnet Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 336 KB |
| Title: | Time Domain Modeling of Active Materials |
| File Type: | Conference Paper |
| Issue: | Volume: S48 Computational Nanophotonics: Advanced Numerical Methods and Applications II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 339 KB |
| Title: | The Way from Natural to Artificial |
| File Type: | Conference Paper |
| Issue: | Volume: 2-1-C Properties, Modelling and Novel Concepts of Artificial Electromagnetic Structures I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 235 KB |
| Title: | The Validationof EM Modelling Codes. A User Viewpoint |
| Abstract: | Computer codes for solving radiation and scattering problems have becomed powerful and widely available. The user of such a code must initially convince himself that his copy of the code executes correctly on his specific computer with his particular compiler. He must then build up expertise in constructing models for solution by the code which obey the restrictions imposed by the "modelling guildelines" accompanying the code in a user's manual. Users often want to solve "real" problems that do not conform to the problem geometry envisaged by the code writer. The user replaces the "real" structure with a computer model solvable by the code, and which obeys the modelling guidelines. The user must then carry out a "model validation" in which the computer model is tested against full-scale or scale model measurements. A successful "model validation" contributes to the user community's "experience base" and lends confidence to both the computer code and to the modelling process. Sometimes an unsuccessful attempt at modeling exposes a genuine limitation of the code. Then a new "modelling guideline" can be formulated to aid other users in avoiding the same difficulties. This paper reviews code development to highlight the origin of "modelling guidelines", and how they are extended by the user community. From the user's point of view, the "experience base" is augmented whenever a successful "model validation" is carried out and reported. Several examples are presented of the difficulties that may be encountered in computer modelling, and how such difficulties lead to further "modelling guidelines" aimed at aiding others in solving similar problems. |
| Author(s): | S.J. Kubina, C.W. Trueman, S.J. Kubina, C.W. Trueman |
| File Type: | Journal Paper |
| Issue: | Volume: 4 Number: 3 Year: 1989 |
| Download Link: | Click here to download PDF File Size: 731 KB |
| Title: | The Success of GPU Computing in Applied Electromagnetics |
| Abstract: | In the field of electromagnetic modeling, whether it is the complex designs for engineered materials or devices and components integrated within their natural environments, there is a big drive for highly efficient numerical techniques to model the performance of complex structures. This often cannot be achieved by conventional computer systems, but rather through using the so-called high performance computing (HPC) systems that utilize hardware acceleration. We review recent General Purpose Graphics Processing Units (GPGPU) computing strategies introduced in four fields of computational electromagnetics: Finite-Difference Time-Domain (FDTD), Finite Elements Method (FEM), Method of Moments (MoM) and ElectroMagnetic Ray Tracing (EMRT). |
| Author(s): | A. Capozzoli, O. Kilic, C. Curcio, A. Liseno |
| File Type: | Express Journal Paper |
| Issue: | Volume: 1 Number: 4 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1478 KB |
| Title: | The Success of GPU Computing in Applied Electromagnetics |
| Abstract: | In the field of electromagnetic modeling, whether it is the complex designs for engineered materials or devices and components integrated within their natural environments, there is a big drive for highly efficient numerical techniques to model the performance of complex structures. This often cannot be achieved by conventional computer systems, but rather through using the so-called high performance computing (HPC) systems that utilize hardware acceleration. We review recent General Purpose Graphics Processing Units (GPGPU) computing strategies introduced in four fields of computational electromagnetics: Finite-Difference Time-Domain (FDTD), Finite Elements Method (FEM), Method of Moments (MoM) and ElectroMagnetic Ray Tracing (EMRT). |
| Author(s): | A. Capozzoli, O. Kilic, C. Curcio, A. Liseno |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 2 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1501 KB |
| Title: | The Success of GPU Computing in Applied Electromagnetics |
| Abstract: | In the field of electromagnetic modeling, whether it is the complex designs for engineered materials or devices and components integrated within their natural environments, there is a big drive for highly efficient numerical techniques to model the performance of complex structures. This often cannot be achieved by conventional computer systems, but rather through using the so-called high performance computing (HPC) systems that utilize hardware acceleration. We review recent General Purpose Graphics Processing Units (GPGPU) computing strategies introduced in four fields of computational electromagnetics: Finite-Difference Time-Domain (FDTD), Finite Elements Method (FEM), Method of Moments (MoM) and ElectroMagnetic Ray Tracing (EMRT). |
| Author(s): | A. Capozzoli, O. Kilic, C. Curcio, A. Liseno |
| File Type: | Express Journal Paper |
| Issue: | Volume: 33 Number: 2 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1501 KB |
| Title: | The Locally-corrected Nystrom Method: Progress and Challenges |
| File Type: | Conference Paper |
| Issue: | Volume: S05 Locally Corrected Nystrom Method and its Applications Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 188 KB |
| Title: | THE COMPUTATION OF LINEAR DISPERSIVE ELECTROMAGNETIC WAVES |
| Abstract: | Numerical solutions of the equations describing electromagnetic pulse propagation in geometrically complex Debye-dispersive dielectrics are used in the development of safety standards for human exposure to non-ionizing radiation. Debye dispersion is a relaxation process, a phenomenon which occurs when the underlying material is forced into non-equilibrium due to the passing waves. This relaxation is typically stiff in applications, and the system of equations is then singularly perturbed. Such systems are notoriously expensive to solve with standard numerical methods. We review previous work related to the numerical solution of such problems, and consider a representative numerical scheme in order to elucidate the nature of the challenge posed to Computational Electromagnetics by the stiffness. Further. an analysis of the stiffness leads us to propose a scheme that seems "natural" for the problem at hand. [Vol. 11, No. 1 (1996), pp 8-16, Special issue on Applied Mathematics: Meeting the challenges presented by computational electromagnetics] |
| Author(s): | Peter G. Petropoulos, Peter G. Petropoulos |
| File Type: | Journal Paper |
| Issue: | Volume: 11 Number: 1 Year: 1996 |
| Download Link: | Click here to download PDF File Size: 708 KB |
| Title: | Teaching Electromagnetics via Virtual Tools and a New Electromagnetic Engineering Program (EMEP) |
| File Type: | Conference Paper |
| Issue: | Volume: CEM for EM Education Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 144 KB |
| Title: | Spoof Surface Plasmons for Guiding and Radiating Electromagnetic Waves |
| File Type: | Conference Paper |
| Issue: | Volume: 6-ME-1 Advanced Plate Antenna and Array Technologies II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 182 KB |
| Title: | Simulation and Optimization of Photonic Crystal Structures |
| File Type: | Conference Paper |
| Issue: | Volume: Computational Electromagnetics for Photonics Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 337 KB |
| Title: | Self-adjoint S-parameter Sensitivities for TLM problems |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Computer-Aided Design of Electromagnetic Structures and Devices Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 80 KB |
| Title: | Scalability of Hybrid Full Wave/Asymptotic EM Solver Techniques for Naval Antennas |
| File Type: | Conference Paper |
| Issue: | Volume: S32 Recent Advances in Asymptotic Methods Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 2554 KB |
| Title: | Review of the Latest Feature Additions to the Electromagnetic Solver FEKO |
| File Type: | Conference Paper |
| Issue: | Volume: S44 EM Modeling Using FEKO I Number: Year: 2016 |
| Download Link: | Login To Download (For Members) File Size: 1179 KB |
| Title: | Review of Six-Port Interferometer Technology |
| File Type: | Conference Paper |
| Issue: | Volume: Six Port Technology in Software Radio Wireless Communication Systems Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 198 KB |
| Title: | Review of SIW Power Capacity and Verification on Multi-Physics Simulation |
| File Type: | Conference Paper |
| Issue: | Volume: 6-ME-3 Multi-physics Simulation of Coupled Field-Circuit Problems Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 364 KB |
| Title: | Review of Selected New Features in FEKO 2018 |
| File Type: | Conference Paper |
| Issue: | Volume: S23 EM Modeling Using FEKO I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 258 KB |
| Title: | Review of RF Cloaking Techniques for Antenna Applications |
| Abstract: | This paper reviews the background phenomenon of various cloaking techniques such as transformation optics, transmission line network, microwave network cloak, scattering cancellation techniques in the applications of antenna field particularly in hiding the obstacle from the electromagnetic source and reducing the mutual coupling between two antennas that was placed closed to each other. Cloaking at multiple frequencies in each cloaking techniques are also compared. The comparative study showed that the scattering cancellation technique based on aperiodic Frequency Selective Surfaces (FSS) structure will dominate the electromagnetic cloaking field in near future. |
| Author(s): | N. Kumutha, K. Hariharan, N. Amutha, B. Manimegalai |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1886 KB |
| Title: | Review of Recent Advances and Future Challenges in Antenna Measurement |
| Abstract: | This paper reviews the last advances in Antenna Measurement Field that took place during the previous years in order to analyse the challenges for the antenna measurement community, both industrial and academic, for the future years. The paper begins with an introductory review of the antenna measurement methodologies innovations, continuing with measurement systems technical improvements and concluding with the challenges for the antenna measurement community in the close future. |
| Author(s): | M. Sierra-Castañer |
| File Type: | Express Journal Paper |
| Issue: | Volume: 1 Number: 2 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 370 KB |
| Title: | Review of Recent Advances and Future Challenges in Antenna Measurement |
| Abstract: | This paper reviews the last advances in Antenna Measurement Field that took place during the previous years in order to analyse the challenges for the antenna measurement community, both industrial and academic, for the future years. The paper begins with an introductory review of the antenna measurement methodologies innovations, continuing with measurement systems technical improvements and concluding with the challenges for the antenna measurement community in the close future. |
| Author(s): | M. Sierra-Castañer |
| File Type: | Express Journal Paper |
| Issue: | Volume: 33 Number: 1 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1558 KB |
| Title: | Review of Recent Advances and Future Challenges in Antenna Measurement |
| Abstract: | This paper reviews the last advances in Antenna Measurement Field that took place during the previous years in order to analyse the challenges for the antenna measurement community, both industrial and academic, for the future years. The paper begins with an introductory review of the antenna measurement methodologies innovations, continuing with measurement systems technical improvements and concluding with the challenges for the antenna measurement community in the close future. |
| Author(s): | M. Sierra-Castañer |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 1 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1558 KB |
| Title: | Review of Complex Looped FDTD and its new applications |
| File Type: | Conference Paper |
| Issue: | Volume: Modeling Techniques for Periodic Structures and Metamaterial Applications - I Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 224 KB |
| Title: | Review of Advanced EM Modeling Techniques in the Computer Code FEKO |
| File Type: | Newsletter Paper |
| Issue: | Volume: 18 Number: 2 Year: 2003 |
| Download Link: | Click here to download PDF File Size: 709 KB |
| Title: | Review -- Grid Computing for Electromagnetics |
| File Type: | Newsletter Paper |
| Issue: | Volume: 20 Number: 1 Year: 2005 |
| Download Link: | Click here to download PDF File Size: 227 KB |
| Title: | Retrospect of Space Solar Power Stations History |
| File Type: | Conference Paper |
| Issue: | Volume: 8-TP-4 In Celebration of 70th Birthday of Prof. Jia-dong Xu II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 1161 KB |
| Title: | Retrospect of Space Solar Power Stations History |
| File Type: | Conference Paper |
| Issue: | Volume: 10-TE-4 In Celebration of 70th Birthday of Prof. Jia-dong Xu III Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 1161 KB |
| Title: | Response Correction Techniques for Microwave Design Optimization |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic-Simulation-Driven-Design: Modeling and Optimization Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 275 KB |
| Title: | Reconfigurable Origami Antennas |
| File Type: | Conference Paper |
| Issue: | Volume: S42 Physically Reconfigurable Antennas and Arrays: Design, Modeling and Materials I Number: Year: 2019 |
| Download Link: | Login To Download (For Members) File Size: 837 KB |
| Title: | Recent Advances in Sensitivity Analysis with Frequency-Domain Full-Wave EM Solvers |
| Abstract: | This paper introduces recent developments in efficient sensitivity analysis with numerical electromagnetic solvers in the frequency domain. We start by reviewing our original discrete approaches for sensitivity analysis. We then propose and investigate, for the first time, two new discrete approaches which enhance the accuracy of the estimated derivatives. All four introduced approaches are based on the adjointvariable method and target solvers on structured grids. Discussion and comparison of the accuracy and convergence for the different approaches are also given. Examples include waveguide and printed structures. |
| Author(s): | S. M. Ali, N. K. Nikolova, M. H. Bakr, S. M. Ali, N. K. Nikolova, M. H. Bakr |
| File Type: | Journal Paper |
| Issue: | Volume: 19 Number: 3 Year: 2004 |
| Download Link: | Click here to download PDF File Size: 256 KB |
| Title: | RAY-TRACING TECHNIQUES FOR MOBILE COMMUNICATIONS |
| Abstract: | In this paper an application for mobile communication of several ray-tracing techniques is presented. The techniques work in combination with deterministic propagation models based on GTD/UTD techniques. Several ray-tracing techniques are reviewed and some results applying one of them, the Angular Zeta Buffer (AZB) method for urban and indoor scenarios are shown, obtaining in all the cases good results comparing with measurements. |
| Author(s): | O. Gutierrez, F. Saez de Adana, I. Gonzalez, J. Perez, M. E. Cetedra, O. Gutierrez, F. Saez de Adana, I. Gonzalez, J. Perez, M. E. Cetedra |
| File Type: | Journal Paper |
| Issue: | Volume: 15 Number: 3 Year: 2000 |
| Download Link: | Click here to download PDF File Size: 2460 KB |
| Title: | Ray-Launching Geometrical Optics in FEKO: A Summary of the Last Four Years of Intensive Development |
| File Type: | Conference Paper |
| Issue: | Volume: 10-TE-3 Recent Advances on Electromagnetics Modeling and Simulation Techniques II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 490 KB |
| Title: | Radar cross section of exhaust ions in HF region |
| File Type: | Conference Paper |
| Issue: | Volume: High Frequency Techniques Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 251 KB |
| Title: | Progress on Microwave Devices Fabricated Using Stereolithography 3-D Printing Technique |
| File Type: | Conference Paper |
| Issue: | Volume: 2-3-C Advanced Manufacturing Technologies for Microwave Devices Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 390 KB |
| Title: | Progress of Tensor-Based High-Dimensional Uncertainty Quantification of Process Variations |
| File Type: | Conference Paper |
| Issue: | Volume: S05 Locally Corrected Nystrom Method and its Applications Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 214 KB |
| Title: | Progress and Future Work on the NS-FDTD Method |
| File Type: | Conference Paper |
| Issue: | Volume: Finite Difference Methods Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 464 KB |
| Title: | Physics-Based Aggregate-Functions Approaches to Large Mom Problems |
| Abstract: | Aggregate functions approaches construct efficient MoM basis functions by suitably grouping standard (e.g. Rao-Wilton- Glisson) functions. The application domains, objectives and related means of achieving them can be significantly different. In this paper we review some recent advances in aggregatefunctions methods, putting them in a unifying perspective. We address matrix compression, multi-resolution sets, low- and high-frequency constructs. They can reduce the degrees of freedom of the problem so as to allow a direct, iteration-free solution, or can accelerate the convergence rate of iterative methods. We analyze compressive methods in more detail, providing general discussion and specific implementation examples. |
| Author(s): | L. Matekovits, G. Vecchi, F. Vico |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 2 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 941 KB |
| Title: | PARALLEL MATRIX SOLVERS FOR MOMENT METHOD CODES FOR MIMD COMPUTERS |
| Abstract: | Parallel algorithms are presented that are suitable for the solution of the system of linear equations generated by moment method problems on local memory Multiple Instruction, Multiple Data (MIMD) parallel computers. The two most widely used matrix solution algorithms in moment method codes are described, namely the conjugate gradient (CG) method and LU decomposition. The underlying philosophy of parallelism is briefly reviewed. Suitable parallel algorithms are then described, presented in pseudo-code, their timing behaviour analyzed the- oretically, and timing results measured on a particular MIMD computer- -a transputer array --are presented and compared to the theoretical timing models. It is concluded that efficient parallel algorithms for both the CG and LU exist and that MIMD computers offer an attractive computational platform for the solution of moment method problems with large numbers of unknowns. [Vol. 8, No. 2 (1993), pp 144-175] |
| Author(s): | David B. Davidson, David B. Davidson |
| File Type: | Journal Paper |
| Issue: | Volume: 8 Number: 2 Year: 1993 |
| Download Link: | Click here to download PDF File Size: 1827 KB |
| Title: | PARALLEL COMPUTATION OF LARGE-SCALE ELECTROMAGNETIC FIELD DISTRIBUTIONS |
| Abstract: | Some experience of the use of high-frequency electromagnetics software on parallel computers is reported. Types of such computers are reviewed and approaches to the parallelisation of existing serial software are discussed. A practical large-scale problem is presented involving the modelling in very fine detail of electromagnetic penetration into biological systems. This was tested on state-of-the-art parallel computers and important practical and strategic aspects of the experience derived are discussed. It was found that considerable programmer effort was required to optimise the software to use the computer architecture effectively, but that efficient acceleration of the run-times of typical computational tasks could be achieved, provided that the tasks were large and were partitioned optimally. |
| Author(s): | Peter S. Excell, Adam D. Tinniswood, Kathleen Haigh-Hutchinson, Peter S. Excell, Adam D. Tinniswood, Kathleen Haigh-Hutchinson |
| File Type: | Journal Paper |
| Issue: | Volume: 13 Number: 2 Year: 1998 |
| Download Link: | Click here to download PDF File Size: 2818 KB |
| Title: | Overview of Mesh Truncation Algorithms in PDEs for Maxwell Equations |
| File Type: | Conference Paper |
| Issue: | Volume: In Tribute To Dr. Zoltan Cendes Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 100 KB |
| Title: | Overview of Inverse Scattering, Imaging, and Parallel Computing |
| File Type: | Conference Paper |
| Issue: | Volume: Efficient Numerical Solutions of Large Multi-dimensional Inverse Scattering Problems Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 182 KB |
| Title: | Optimizing the Parallel Implementation of a Finite Difference Time Domain Code on a Multi-user Network of Workstations |
| Abstract: | The implementation of a parallel, three dimensional, finite difference time domain (FDTD) computer program is considered and applied to a test scattering problem on a multi-user network of desktop workstations. The computation has primarily been done on a local area network (LAN) using six identical HP 9000/715 workstations (i.e. a homogeneous environment) with the Parallel Virtual Machine (PVM) software being employed as the communications harness.In this paper the sequential and parallel FDTD approaches are reviewed. We investigate the factors which cause a reduction in efficiency in the latter, such as host allocation and load balancing. We propose a task migration process, which is efficient for the FDTD algorithm, as a partial solution. The advantages of this approach are discussed and further developments based on available computational resources are suggested |
| Author(s): | J. V. Mullan, C. J. Gillan, V. F. Fusco, J. V. Mullan, C. J. Gillan, V. F. Fusco |
| File Type: | Journal Paper |
| Issue: | Volume: 13 Number: 2 Year: 1998 |
| Download Link: | Click here to download PDF File Size: 710 KB |
| Title: | Optimizing Multiple GPU FDTD Simulations in CUDA |
| File Type: | Conference Paper |
| Issue: | Volume: Parallel and Hardware Acceleration for Computational Electromagnetics Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 44 KB |
| Title: | On the numerical modeling of graphene and silicene for EM solvers |
| File Type: | Conference Paper |
| Issue: | Volume: Computational Methods in Nanoelectromagnetics Number: Year: 2014 |
| Download Link: | Login To Download (For Members) File Size: 301 KB |
| Title: | On the Discretization of Fredholm Integral Equations of First Kind Using Compactly Supported Wavelets |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Integral Equation Techniques Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 452 KB |
| Title: | Numerical Validation of a Boundary Element Method with Electric Field and Its Normal Derivative as the Boundary Unknowns |
| Abstract: | We recently developed a surface integral equation method where the electric field and its normal derivative are chosen as the boundary unknowns. After reviewing this formulation, we present preliminary numerical calculations that show good agreement with the known results. These calculations are encouraging and invite the further development of the numerical solution. |
| Author(s): | J. Markkanen, A. J. Yuffa, J. A. Gordon |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 2 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2963 KB |
| Title: | Numerical Validation of a Boundary Element Method With E and @E @N as the Boundary Unknowns |
| File Type: | Conference Paper |
| Issue: | Volume: S28 Computational Methods for Complex EM Domains, Integral Equation Methods Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 188 KB |
| Title: | Numerical Simulation Approaches for Phased Array Design |
| Abstract: | Abstract - This paper reviews the two well-known numerical simulation techniques that are widely used in antenna modeling; the finite-difference time-domain (FDTD) and the Method of Moments (MoM). The packages FDANT (prepared in Fortran language by using FDTD) and NEC2 (public domain code for the MoM) are used to model various types of antenna arrays, their advantages/disadvantages are discussed on characteristic design examples, and they are calibrated one against the other. Also, a simple Matlab package (ANTEN_GUI) for the visualization of radiation patterns, beam forming and beam steering capabilities of user-designed planar arrays of isotropic radiators (which can be used to test the above mentioned packages and as an educational tool, in e.g., antennas and propagation lectures) is introduced1. |
| Author(s): | L. Sevgi, L. Sevgi |
| File Type: | Journal Paper |
| Issue: | Volume: 21 Number: 3 Year: 2006 |
| Download Link: | Click here to download PDF File Size: 1360 KB |
| Title: | Neural Network Based Methods for Nonlinear Behavioral Modeling of RF and Microwave Circuits |
| File Type: | Conference Paper |
| Issue: | Volume: Microwave Modeling and CAD Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 202 KB |
| Title: | Near-field RCS Measurement and Microwave Imaging Diagnosis-A Review of NWPU Work |
| File Type: | Conference Paper |
| Issue: | Volume: 9-P-2 Poster Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 181 KB |
| Title: | Multiple Beam Antenna Technology for Satellite Communications Payloads |
| Abstract: | Abstract—This paper reviews multiple beam antenna (MBA) technologies that are applicable for satellite communications payloads. It provides design, performance analysis, and hardware implementation aspects of various types of MBAs that include reflector MBAs, phased array MBAs, and lens MBAs. Parametric design of these MBAs and RF analysis for coverage gain and inter-beam isolation are given. Recent advances and trends in MBA technologies for space applications are discussed. |
| Author(s): | S. Rao, M. Tang, C. Hsu, S. Rao, M. Tang, C. Hsu |
| File Type: | Journal Paper |
| Issue: | Volume: 21 Number: 3 Year: 2006 |
| Download Link: | Click here to download PDF File Size: 1464 KB |
| Title: | Multi-Layer LCP Technology for Millimetre Wave Applications |
| File Type: | Conference Paper |
| Issue: | Volume: System-on-Package (SoP) Wireless Components Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 137 KB |
| Title: | Modeling and Analysis of a Dual-Band Dual-Polarization Radiator Using FEKO |
| Abstract: | A dual-band hybrid antenna element comprising of microstrip and waveguide radiating elements is theoretically investigated through computer simulations. The low band radiator is a Shorted Annular Ring (SAR) microstrip antenna and the high band antenna is an open ended circular waveguide. First, the characteristics of a SAR patch antenna are presented and reviewed. Then the dual-band antenna configuration is described, which is realized by forming a waveguide radiator in the shorted region of the SAR microstrip antenna. Modeling and analysis of the SAR patch antenna and the hybrid element are investigated using the method-of-moment-based software package FEKO. The analysis includes return loss computations showing the element bandwidth at different frequency bands and the radiation patterns in the E- and H- planes. Feeding the element in phase quadrature produces circular polarizations (CP). The radiation patterns of the CP dual-band element are also analyzed using FEKO and the axial ratio performance is subsequently assessed |
| Author(s): | Amir I. Zaghloul, C. Babu Ravipati, M. T. Kawser, Amir I. Zaghloul, C. Babu Ravipati, M. T. Kawser |
| File Type: | Journal Paper |
| Issue: | Volume: 22 Number: 1 Year: 2007 |
| Download Link: | Click here to download PDF File Size: 617 KB |
| Title: | Metamaterial Enhanced Antenna Systems: A Review |
| File Type: | Conference Paper |
| Issue: | Volume: S08 Design, Analysis and Applications of EM Metasurfaces I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 415 KB |
| Title: | MERCURY MOM: An Applied RWG EM Scattering Code for Electrically Large Bodies |
| File Type: | Conference Paper |
| Issue: | Volume: 30 Years of RWG Basis Functions Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 99 KB |
| Title: | Inverse Scattering and Information Management – Trends and Envisaged Strategies |
| File Type: | Conference Paper |
| Issue: | Volume: 4-MP-5 Inverse Scattering - Theory, Methods and Applications I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 254 KB |
| Title: | Introduction to Genetic Algorithms in Electromagnetics |
| Abstract: | This special issue of the ACES Journal is devoted to nev developments in Genetic Algorithm (GA) applications in computational electromagnetics. Genetic Algorithms have become extremely popular in the computational electromagnetics literature. The papers included in this special issue are very arcane, so I decided to include an unreviewed tutorial overview at the last minute as an introduction for those of you who are at a more basic level. GAs model natural selection and genetics on a computer to optimize a wide range of problems. |
| Author(s): | Randy L. Haupt, Randy L. Haupt |
| File Type: | Journal Paper |
| Issue: | Volume: 15 Number: 2 Year: 2000 |
| Download Link: | Click here to download PDF File Size: 2442 KB |
| Title: | Higher-order (LT/QN) vector finite elements for waveguide analysis |
| Abstract: | The finite element (FE) formulation for waveguide discontinuity analysis is reviewed and extended to multiple, arbitrarily-oriented ports. Several higher-order vector elements - specifically hierarchal linear tangential/quadratic normal (LT/QN) - are compared, and the extensions required to incorporate LT/QN elements in the formulation are presented. The improved accuracy afforded by LT/QN elements compared to constant tangential/linear normal (CT/LN) elements is investigated by considering energy conservation in an empty waveguide. Results obtained using both CT/LN and LT/QN elements are also shown for a problem of engineering interest: an E-plane bend. Results for the LT/QN elements compare especially well to approximate analytical results using quite coarse meshes. The paper concludes with a discussion of the use of iterative solvers and possible convergence problems encountered when using higher-order elements. |
| Author(s): | David B Davidson, David B Davidson |
| File Type: | Journal Paper |
| Issue: | Volume: 17 Number: 1 Year: 2002 |
| Download Link: | Click here to download PDF File Size: 152 KB |
| Title: | Genetic Algorithm Applications for Phased Arrays |
| Abstract: | Abstract—Analytical approaches to phased array optimization started in the mid 1940s and transitioned to numerical techniques that can find a local minimum. Computers spurred the development of many different local optimization algorithms that worked well for a few variables and a cost function with a single minimum. In the 1990s, the genetic algorithm (GA) emerged as a competent optimization algorithm for a wide range of complex cost functions. This paper reviews phased array optimization and lays the foundation for the use of the GA. An extensive reference list is provided and some future research areas are discussed. |
| Author(s): | R. L. Haupt, R. L. Haupt |
| File Type: | Journal Paper |
| Issue: | Volume: 21 Number: 3 Year: 2006 |
| Download Link: | Click here to download PDF File Size: 340 KB |
| Title: | GA-MoM Optimization of Slot Arrays |
| File Type: | Conference Paper |
| Issue: | Volume: S33 Electromagnetic Simulation for RF and Microwave Design Optimization Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 447 KB |
| Title: | Fundamental Limitations on the Use of Open-Region Boundary Conditions and Matched Layers to Solve the Problem of Gratings in Metallic Screens |
| Abstract: | Interest in accurate modeling of the electromagnetic wave scattering from grating surfaces has been renewed due to recent advances in the manipulation and localization of the light in novel application of plasmonic resonance. This work briefly reviews the frequency-domain finite methods that have been used extensively to solve the grating problem. Emphasis will be placed on the finite methods that use local boundary operators or matched layers to truncate the computational boundary. It is shown that significant errors can be generated when using either of these two mesh truncation techniques even if the truncation boundaries are receded to avoid any evanescent waves emanating from the gratings. To quantify the error, the solutions obtained using the boundary condition or matched layers are compared to the solutions obtained using either mode matching or the surface integral equation method, both of which are devoid of truncation boundary related approximations and errors. Additionally, limitations on the use of the periodic boundary condition to truncate the mesh for periodic problems are also addressed. |
| Author(s): | B. Alavikia, O. M. Ramahi |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 8 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 1492 KB |
| Title: | Flammer’s Exact Solution for the Circular Conducting Disk: A Benchmark Problem for EM Software Validation |
| File Type: | Conference Paper |
| Issue: | Volume: S03 Computational Electromagnetics, Advanced Algorithms and Emerging Applications Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 319 KB |
| Title: | FINITE ELEMENTS IN ELECTROMAGNETICS: A JUBILEE REVIEW |
| Abstract: | This review describes the historical origins and the present state of the finite element method in electromagnetics. The foundation principles of finite elements are briefly reviewed. Applications are mainly to two and three dimensional problems of microwave and optical structures. The major types of scalar element are noted, and edge-interpolative vector elements are reviewed, firstly for the waveguide problem and then in three dimensions. An extensive bibliography is given, particularly stressing review papers. [Vol. 9, No. 2 (1994), Special Issue on The Numerical Computation of Low Frequency Electromagnetic Fields, pp 10-24] |
| Author(s): | J. Brian Davies, Peter P. Silvester, J. Brian Davies, Peter P. Silvester |
| File Type: | Journal Paper |
| Issue: | Volume: 9 Number: 2 Year: 1994 |
| Download Link: | Click here to download PDF File Size: 1459 KB |
| Title: | FDTD Modeling of Electromagnetic and Thermal Dosimetry in Human for Microwave Exposures |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Finite Difference Time Domain Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 111 KB |
| Title: | EVOLUTION OF A SUITE OF COMPUTATIONAL MODELING TOOLS FOR MOBILE TELEPHONE DOSIMETRY STUDIES AT THE UNIVERSITY OF BRADFORD, U.K. |
| Abstract: | The evolution of a set of software and skills for the computational simulation of the interaction of mobile telephones with the human body is reviewed. These have been developed and applied in the authors' research group over the past decade. The work has aimed at maximization of realism in the representation of the body components and the telephone through use of MRI images, use of resolutions down to 1mm, incorporation of a hand into the model, development of a rotation algorithm for the telephone, development of techniques for modeling helical antennas, and development of hybrid techniques to allow the Method of Moments to be used to model the telephone, combined with finite difference methods for the human tissues. Generic experience and specimen results are presented. It is argued that the policy of pursuing realism in the simulation, beyond the level that is sufficient on physical grounds, is essential to convince the non-specialist public of the trustworthiness of the work. |
| Author(s): | Peter S. Excell, John A. Vaul, Peter S. Excell, John A. Vaul |
| File Type: | Journal Paper |
| Issue: | Volume: 16 Number: 2 Year: 2001 |
| Download Link: | Click here to download PDF File Size: 1082 KB |
| Title: | Estimation of Mutual Coupling in Irregular Planar Arrays |
| File Type: | Conference Paper |
| Issue: | Volume: S14 Numerical Methods for Analysis, Design and Measurement of Antennas I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 755 KB |
| Title: | Energy Paradigms of Augmented Tags for the Internet of Things Deployment |
| File Type: | Conference Paper |
| Issue: | Volume: S33 Electromagnetic Techniques for the Internet of Things I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 312 KB |
| Title: | EMX: Overcoming Silicon Chip EM Simulation Challenges for Passive Circuit Analysis and Model Development |
| File Type: | Conference Paper |
| Issue: | Volume: S23 Electromagnetic Modeling for Electronic Design Automation Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 405 KB |
| Title: | Electromagnetic Stimuli in Therapeutics and Resuscitation |
| File Type: | Conference Paper |
| Issue: | Volume: S53 Biological Effects of Electric, Magnetic and Electromagnetic Fields I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 428 KB |
| Title: | Electromagnetic Diffraction Modeling: High Frequency Asymptotics vs. Numerical Techniques |
| Abstract: | Electromagnetic diffraction modelling and recent numerical simulation approaches, on the canonical 2D non-penetrable wedge scattering problem, are reviewed in this introduction paper. |
| Author(s): | L. Sevgi |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 7 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 2024 KB |
| Title: | Development of Wideband L-Probe Coupled Patch Antenna |
| Abstract: | The patch antenna fed by an L-shaped probe was proposed in 1998. This feeding method, and its modified version, the meandering strip, has led to the development of a new class of wideband patch antennas which can be operated in linear, circular or dual polarization with excellent performance characteristics. L-probe coupled patch antennas are simple in structure and low in material and production costs. Moreover, it can be designed with dual wideband performance which is very attractive for modern mobile communications. This paper presents a review of the general designs for linearly and circularly polarized L-probe patch antennas. Comparisons between measured and simulated results are presented. Methods for gain enhancement and cross polarization suppression are also introduced. The designs and performances of two dual-band wideband L-probe fed patch antennas are also described. |
| Author(s): | Kwai Man Luk, Kai Fong Lee, Hau Wah Lai, Kwai Man Luk, Kai Fong Lee, Hau Wah Lai |
| File Type: | Journal Paper |
| Issue: | Volume: 22 Number: 1 Year: 2007 |
| Download Link: | Click here to download PDF File Size: 546 KB |
| Title: | Development of the Incremental IEMF Method as an Analycital Proof for the Validity of FARS (Far-field Analysis of Radiation Sources) |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Integral Equation Based Techniques II Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 283 KB |
| Title: | Detect and Pointing Algorithm's Performance for a Planar Smart Antenna Array: A Review |
| Abstract: | An adaptive antenna array combines the signal of each element, using some constraints to produce the radiation pattern of the antenna, while maximizing the performance of the system. Direction of arrival (DOA) algorithms are applied to determine the directions of impinging signals, whereas beamforming techniques are employed to determine the appropriate weights for the array elements, to create the desired pattern. In this paper, a detailed analysis of both categories of algorithms is made, when a planar antenna array is used. Several simulation results show that it is possible to point an antenna array in a desired direction based on the DOA estimation and on the beamforming algorithms. A comparison of the performance in terms of runtime and accuracy of the used algorithms is made. These characteristics are dependent on the SNR of the incoming signal. |
| Author(s): | T. Varum, J. N. Matos, P. Pinho |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 8 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 3692 KB |
| Title: | Coupled EM-Structural Analysis in Convected Coordinates |
| File Type: | Conference Paper |
| Issue: | Volume: S47 Integral Equation Solvers for Real-Life Applications I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 226 KB |
| Title: | COMPUTER-BASED ELECTROMAGNETlC EDUCATION |
| Abstract: | Computers provide an exciting opportunity for boosting electromagnetic education and corporate training. Animated graphics of the wave propagation phenomenon, visualization of the abstract and highly mathematical subjects, one-on-one and self-paced tutoring, and the ability to mimic often unavailable and expensive laboratory experiments are among the often-cited benefits of a computer-based electromagnetic education. In this paper, we review the activities of the NSF/IEEE Center for Computer Applications in Electromagnetic Education (CAEME). This Center was established to stimulate and accelerate the use of computers and software tools in EM education. A reflection on the extensive software package developed and distributed by the CAEME Center is described and examples of the developed software are presented. To help integrate available EM software in classroom teaching and corporate training, CAEME developed four multimedia lessons for instruction. These interactive media lessons integrate and allow individuals to interactively manipulate information from multimedia sources such as video, software, and animated graphics and also include instructional information such as quizzes and tutorials to help evaluate the students' performance. Features of these lessons are presented, and future developments in the Center's activities are described. [Vol. 8, No. 1, (1993), Special Issue on Computer Applications in Electromagnetics Education, pp 77-107] |
| Author(s): | Magdy F. Iskander, Magdy F. Iskander |
| File Type: | Journal Paper |
| Issue: | Volume: 8 Number: 1 Year: 1993 |
| Download Link: | Click here to download PDF File Size: 4497 KB |
| Title: | Computational Electromagnetics for the Evaluation of EMC Issues in Multi-Component Energy Systems |
| Abstract: | This paper reviews the physics based modeling based on the electromagnetic stray fields and interference in the electric power network. The low frequency as well as high frequency equivalent source modeling of the power components for the study of radiated and conducted electromagnetic compatibility were implemented. The 3-D finite element analysis with some modification were applied in the solution method, as well as meshing strategies for the simulation of large scale components. Moreover, the stray field of the components was utilized for improving the control of the machine-drive system using hardware in loop method. The optimization in the design of the components such as the power converter based on the EMC compliance was also applied. This was achieved by coupling MATLAB with 3-D finite element technique for applying the numerical optimization techniques. The results were verified experimentally. |
| Author(s): | M. R. Barzegaran, O. A. Mohammed |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 12 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 3709 KB |
| Title: | COMPUTATION OF MULTIPOLE MOMENTS FOR SHORT THIN WIRE CHIRAL STRUCTURES |
| Abstract: | This paper considers the computation of the multipole moments of small chiral wire structures. The multipole moments are reviewed and it is shown that the charge induced on the wire must be accurately computed. A quasistatic thin-wire Galerkin Method of Moments formulation has been developed to numerically compute the charge distribution. The chiral structures under consideration are on the borderline of "thin" and a Body of Revolution Method of Moments formulation has also been developed for use as a check on the accuracy of the thin-wire approximations. It is shown that the "standard" thin-wire formulation is not sufficiently accurate, but the relatively simple addition of an end-cap greatly improves the convergence and accuracy of the formulation with acceptable computation cost. Finally, the formulation is extended to include bent wires, permitting the electric and magnetic dipole moments as well as the electric quadrupole moment to be calculated for a small chiral structure. [Vol. 10, No. 3 (1995), Special Issue on Advances in the Application of Method of Moments to Electromagnetic Radiation and Scattering Problems, pp 129-138] |
| Author(s): | Isak Petrus Theron, David Bruce Davidson, Johannes Hendrik Cloete, Isak Petrus Theron, David Bruce Davidson, Johannes Hendrik Cloete |
| File Type: | Journal Paper |
| Issue: | Volume: 10 Number: 3 Year: 1995 |
| Download Link: | Click here to download PDF File Size: 905 KB |
| Title: | Compressive Processing for Computational Electromagnetics – Theoretical Basics, Current Trends and Advances |
| File Type: | Conference Paper |
| Issue: | Volume: 7-TA-5 Compressive Sensing in Applied Computational Electromagnetics - Trends and Advances Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 591 KB |
| Title: | Comparison and Analyzing of Propagation Models with Respect to Material, Environmental and Wave Properties |
| Abstract: | This paper presents a study on a class of algorithms based on Uniform Theory of Diffraction (UTD) for multiple diffractions. Within this context Slope UTD with Convex Hull (S-UTD-CH) model based on Slope UTD and Fresnel zone concept was reviewed. S-UTD-CH model can be used for fast and more accurate field prediction for multiple diffractions in transition zone. An extensive simulation results for comparison of UTD based algorithms with respect to the computation time and accuracy was provided. Furthermore, the study shows how relative permittivity constant, conductivity and inner angle of wedge and polarization type affect the relative path loss. |
| Author(s): | M. B. Tabakcioglu, D. Ayberkin, A. Cansiz |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 6 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 424 KB |
| Title: | Comparative Study on Improved and Traditional Equivalent Circuit of Long Primary Double-Sided Linear Induction Motor |
| Abstract: | Based on the quasi-two-dimensional (2D) field model of long primary double-sided linear induction motor (LPDLIM), an improved equivalent circuit model is proposed. First, the traditional equivalent circuit of LPDLIM is reviewed. Second, the skin effect correction coefficients for the secondary equivalent resistance and excitation reactance, and the secondary leakage inductance are derived. Moreover, an improved equivalent circuit model for LPDLIMs is presented, in which the leakage reactance of the secondary is considered, and the excitation reactance and secondary resistance are modified by the correction coefficients independently. Then, the slip frequency characteristics of various effect forces and variations of forces under different operations and mechanical air gap width are presented. Finally, the calculated forces by the proposed equivalent circuit are validated by the finite element method results and also compared with that of the traditional equivalent circuit model. |
| Author(s): | Q. Zhang, H.-J. Liu, Z.-Y. Zhang, T.-F. Song, Y. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 11 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1780 KB |
| Title: | Cloud Computing Simulation Tools for Nanophotonics at nanoHUB.org |
| File Type: | Conference Paper |
| Issue: | Volume: Computational Nanophotonics: Time – Domain Multiphysics, Meshless Methods and Non – Linear Optics Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 413 KB |
| Title: | Cloud Computing for the Science of Light: Nanophotonics Tools at nanoHUB.org |
| File Type: | Conference Paper |
| Issue: | Volume: Modeling of Metamaterials and Transformation Based Devices Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 4202 KB |
| Title: | Characterization of a Planar Two-Arm Self-Complementary Square Spiral Antenna Using the Numerical Electromagnetics Code (NEC) |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic-Simulation-Driven-Design: Modeling and Optimization Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 604 KB |
| Title: | Characteristic Basis Function Method (CBFM)—An Iteration-free Domain Decomposition Approach in Computational Electromagnetics |
| Abstract: | In this paper we review a novel Domain Decomposition (DD) approach, called the Characteristic Basis Function Method (CBFM), which tackles large-scale electromagnetic problems by generalizing the concept of principle of localization that forms the cornerstone of asymptotic methods. The paper shows that the problem of having to deal with large matrices that arise in the conventional formulation of large problems with the Method of Moments (MoM) can be obviated, by dividing the original large problem into a number of smaller sub-problems that are more manageable to handle. However, unlike the conventional DD approaches that typically rely upon iteration algorithms to account for the inter-coupling between the subdomains, the CBFM tackles the problem with direct solvers instead. It is possible to do this in the context of CBFM, because it reduces the original large system matrix into one whose size is orders of magnitude smaller, and is appropriately called the “reduced matrix.” Furthermore, an important salutary feature of CBFM is that the algorithm is naturally parallelizable, an attribute that distinguishes it from many other CEM solvers, and makes it well suited for parallel platforms that have become ubiquitous in recent years. This, in turn, enables us to take advantage of the power of these platforms and to solve, numerically efficiently, large problems that were well beyond our reach in the past. The paper also shows that the basic concepts of CBFM are quite general, and they not only apply to MoM, but can also be tailored for both FEM and FDTD. Index Terms─ Characteristic Basis Function Method (CBFM), Domain Decomposition, Method of Moments (MoM), Finite element Method (FEM), Finite Difference Time Domain (FDTD). |
| Author(s): | R. Mittra |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 2 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 1733 KB |
| Title: | Calculator of WPT Efficiency between Transmitting and Receiving Elements |
| File Type: | Conference Paper |
| Issue: | Volume: 1-3-D Wireless Power Transfer Supported by Computational Electromagnetics Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 530 KB |
| Title: | Beam Scanning Reflectarray Antennas: A Technical Review |
| File Type: | Conference Paper |
| Issue: | Volume: Student Paper Competition Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 52 KB |
| Title: | Beam Scanning Reflectarray Antennas: A Technical Review |
| File Type: | Conference Paper |
| Issue: | Volume: Latest Developments of Reflect/Transmit Array Antennas Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 52 KB |
| Title: | Avoiding the Time-static Simplification in the Simulation of Time-varying Materials |
| File Type: | Conference Paper |
| Issue: | Volume: S07 Advances in Electromagnetics of Complex Media and Metamaterials - I Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 637 KB |
| Title: | Artificial Intelligence Technology and Engineering Applications |
| Abstract: | There has been sixty-year development of the artificial intelligence (AI) and the maturation of AI techniques is now leading to extensive applications and industrialization. In this paper, authors review the connotation and evolution of AI techniques and engineering applications. A four-layer framework of the AI technology system is summarized in this paper to help readers understand AI family. Engineering applications of AI techniques have made remarkable progress in the recent years, for instance, applications in fault diagnosis, medical engineering, petroleum industry and aerospace industry. By introducing the state-of-the-art of AI technologies, it can help the researchers in both engineering and science fields get ideas on how to apply AI techniques to solve application-related problems in their own research areas. |
| Author(s): | X. Li, H. Jiang |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 5 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1659 KB |
| Title: | Application of the Radial Point Interpolation Method as Meshless Time-Domain Technique in Electromagnetics |
| File Type: | Conference Paper |
| Issue: | Volume: Student Paper Competition Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 0 KB |
| Title: | Application of the Radial Point Interpolation Method as Meshless Time-Domain Technique in Electromagnetics |
| File Type: | Conference Paper |
| Issue: | Volume: Recent Developments and Applications with Time-domain Modeling Techniques Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 3213 KB |
| Title: | APPLICATION OF NUMERICAL MODELING TECHNIQUES IN ELECTROMAGNETIC HYPERTHERMIA |
| Abstract: | Electromagnetic hyperthermia has been demonstrated to be a safe and useful adjuvant to ionizing radiation in the treatment of malignant tumors. However, applicators and systems for delivering the optimum treatment prescribed by the physicians are far from being available at present. Computer modeling can play a significant role in the design of better heating equipment and in improving the quality of the hyperthermia treatments currently being administered. There is an active ongoing research to develop suitable calculational models using a variety of numerical techniques. But several gaps exist in the current knowledge regarding the validity of these numerical simulations in the clinical context. The development of treatment planning systems similar to those used for radiation therapy requires resolution of these issues. Of the different numerical modeling approaches currently being developed, the finite-difference time-domain (FD-TD) technique has been extensively applied to calculate specific absorption rate (SAR) patterns in complex 3-D heterogeneous biological objects primarily because it is accurate and has a small computer burden relative to frequency-domain integral equation and finite element techniques. Following a brief review of the historical development of numerical modeling of electromagnetic interaction with biological structures in the hyperthermia context, examples of recent calculations using FD-TD technique in realistic situations in electromagnetic hyperthermia are provided. It has been observed from 2-D calculations, that the water bolus, routinely used in the clinic to provide energy coupling and surface (skin) temperature control, and the inhomogeneous tissue structures significantly modify the SAR patterns compared to patterns computed in planar and homogeneous structures. In conclusion, future areas of work are identified and discussed. [Vol. 7, No. 2, pp. 61-71 (1992), Special lssue on Bioelectromagnetic Computations] |
| Author(s): | V. Sathiaseelan, A. Taflovel, M.J. Picket-Mayl, C. Reuterl, B. B. Mittal, V. Sathiaseelan, A. Taflovel, M.J. Picket-Mayl, C. Reuterl, B. B. Mittal |
| File Type: | Journal Paper |
| Issue: | Volume: 7 Number: 2 Year: 1992 |
| Download Link: | Click here to download PDF File Size: 945 KB |
| Title: | Antennas Wrapped up on Slender Column |
| File Type: | Conference Paper |
| Issue: | Volume: S24 Mobile and Small Antennas I Number: Year: 2016 |
| Download Link: | Login To Download (For Members) File Size: 332 KB |
| Title: | Antenna Developments for Military Applications |
| Abstract: | A review of current, past and projected activities in antenna development indicates a broad spectrum of requirements, and subsequently a variety of innovations to meet these requirements for military radar and communications systems. Designing the antennas in the operating environment, known as in-situ design, is an important factor in guaranteeing the successful operation of the antenna in the field. This paper presents the basic blocks in antenna development, followed by examples of some antennas developed at the Army Research Laboratory for military systems and applications. These include Rotman lenses as beam formers for electronically scanning arrays; phased arrays using MEMS phase shifters at 30 GHz; a 76-GHz narrow beam, low-sidelobe antenna for collision avoidance radar; and other specialized antennas. Of special interest is an effort on developing and using metamaterials in antenna designs, where practical realizations of such materials have the potential of improving the performance and reducing the size of antennas. |
| Author(s): | A. I. Zaghloul, S. J. Weiss, W. K. Coburn |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 1 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 1198 KB |
| Title: | Anonymous Peer review. Time to Move on? |
| File Type: | Newsletter Paper |
| Issue: | Volume: 22 Number: 1 Year: 2007 |
| Download Link: | Click here to download PDF File Size: 115 KB |
| Title: | Analytical Approximations for the Maximum-to-mean Ratio of the E-field in a Reverberation Chamber: A Review |
| Abstract: | The expected value of the maximum value of the rectangular E-field is important in radiated susceptibility testing in a reverberation chamber. In this paper, different forms of equations for the maximum-to-mean ratio of the rectangular E-field are reviewed. Important derivations are summarized and detailed. It is interesting to note that some series which could be difficult to deal with from mathematics could be solved efficiently from physical point of view. The relationship between the independent sample number N and the parameters in generalized extreme value distribution is also given. |
| Author(s): | Q. Xu, R. Jia, L. Geng, H. Guo, Y. Zhao |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 8 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 1349 KB |
| Title: | An Overview of Equivalent Circuit Modeling Techniques of Frequency Selective Surfaces and Metasurfaces |
| Abstract: | Circuit analysis of frequency selective surfaces is reviewed with the aim to underline range of validity of different models and their advantages in terms of simplicity and physical insight. The circuit approach is based on an equivalent representation of the FSSs with series or shunt connections of inductances and capacitances. Dense non-resonant periodic surfaces (i.e.: grid or patch arrays) can be analyzed analytically by computing the values of inductors or capacitors via the homogenization theory. As the lattice period increases with respect to the operating wavelength or the element shape becomes resonant, a fully analytical circuital approach fails, in particular, in the presence of thin substrates. However, simple circuit approaches can still be employed by deriving lumped parameters values via a quick pre-processing and then generalizing them. The results are accurate up to the resonant frequency region of the element. By including an additional lumped element it is possible, taking into account the effect of the first high order Floquet harmonic. The multi-mode formulation is also able to catch the highly nonlinear response of FSS screens in the grating lobe region provided that the current profile of the element does not change significantly. |
| Author(s): | F. Costa, A. Monorchio, G. Manara |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 12 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 1301 KB |
| Title: | An Incomplete Review of Fast Multipole Methods–from Static to Wideband–as Applied to Problems in Computational Electromagnetics |
| Abstract: | Fast multipole methods (FMM) and their immediate predecessors, tree codes, were developed in response to the need for solving Nbody problems that occur in applications as varied as biophysics, computational chemistry, astrophysics and electromagnetics. In all these areas, it is necessary to compute long range potentials of the form 1/R between a dense distribution of point charges, where R is the distance between any two charges. Often, repeated evaluation of these potentials is necessary. It is apparent that the cost of direct evaluation, which scales as O(N2) for N degrees of freedom, forms a fundamental bottleneck. FMM and tree methods ameliorate the cost associated with these computation; CPU times of these method scale as O(N). It stands to reason that FMM has had a seminal impact on a multitude of fields, so much so, that it was recognized as one of the top ten algorithms of the past century. A method to rapidly compute potentials of the form e-j κR/R soon followed. As the reader is aware, these potentials are the crux of integral equation based analysis tools in electromagnetics and the advent of these methods have transformed the face of computational electromagnetics. Consequently, the state of art of integral equation solvers has grown by leaps and bounds over the past decade. This paper attempts to present a detailed review of the state of art of FMM based methods that are used in computational electromagnetics, from the static to the high frequency regime. |
| Author(s): | M. Vikram, B. Shanker |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 2 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 889 KB |
| Title: | Advances of Neural Network Modeling Methods for RF/Microwave Applications |
| Abstract: | Abstract: This paper provides an overview of recent advances of neural network modeling techniques which are very useful for RF/microwave modeling and design. First, we review neural network inverse modeling method for fast microwave design. Conventionally, design parameters are obtained using optimization techniques by multiple evaluations of EM-based models, which take a long time. To avoid this problem, neural network inverse models are developed in a special way, such that they provide design parameters quickly for a given specification. The method is used to design complex waveguide dual mode filters and design parameters are obtained faster than the conventional EM-based technique while retaining comparable accuracy. We also review recurrent neural network (RNN) and dynamic neural network (DNN) methods. Both RNN and DNN structures have the dynamic modeling capabilities and can be trained to learn the analog nonlinear behaviors of the original microwave circuits from input-output dynamic signals. The trained neural networks become fast and accurate behavioral models that can be subsequently used in systemlevel simulation and design replacing the CPUintensive detailed representations. Examples of amplifier and mixer behavioral modeling using the neural-network-based approach are also presented. |
| Author(s): | H. Kabir, Y. Cao, Y. Cao, Q. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 5 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 343 KB |
| Title: | Advances in the Adjoint Variable Method for Time-Domain Transmission Line Modeling |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Time Domain Techniques Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 0 KB |
| Title: | Advances in the Adjoint Variable Method for Time-Domain Transmission Line Modeling |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Time Domain Techniques Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 82 KB |
| Title: | Advanced Modeling of Characteristic Mode Theory for Antenna Applications |
| File Type: | Conference Paper |
| Issue: | Volume: 2-1-A Brainstorm for Computational Electromagnetics: What We Have Achieved and What We Will Do I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 473 KB |
| Title: | Active Millimeter Wave Imaging System with Sparse Antenna Array |
| File Type: | Conference Paper |
| Issue: | Volume: 2-4-D Millimeter Wave/THz Imaging I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 409 KB |
| Title: | Active Metamaterial Incorporating Gain Device/Medium: A Review |
| Abstract: | Metamaterials intrigue many exciting applications in the broad electromagnetic spectrum ranging from microwave to optics. However, many of the envisaged applications still remain in theory, largely because of the intrinsic loss and dispersion associated with passive metamaterials. Incorporating active devices or media into conventional passive metamaterial structures for loss compensation, as well as dispersion control, is very attractive and may finally enable many desired applications. In addition, because of the added design degree of freedom in active metamaterials, new and rich physical phenomena and insights can be discovered. In this paper, we review the recent progress in the realm of active, gain-assisted metamaterials. Physical limitations on loss and bandwidth of metamaterials are firstly discussed. Recent experimental efforts in transmission-line and volumetric metamaterials with net gain in the microwave and optical regime are then examined. The idea of utilizing non-Foster active devices to reduce the dispersion and achieve broad bandwidth is also presented. Finally, one of the important issues of active metamaterial design, stability, is briefly discussed. |
| Author(s): | Q. Tang, H. Xin |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 12 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 975 KB |
| Title: | A VOLUME INTEGRAL CODE FOR EDDY-CURRENT NONDESTRUCTIVE EVALUATION |
| Abstract: | This paper is an extension of J. R. Bowler, H. A. Sabbagh, and L. D. Sabbagh, "A Computational Model of Eddy-Current Probes Over a Stratified Composite Workpiece," which was presented at the 4th Annual Review of Progress in Applied Computational Electromagnetics, Monterey, CA, March 1988. It describes an application of modern methods of computational electromagnetics to the problem of eddy-current nondestructive evaluation (NDE). Specifically, a volume integral equation is developed that can be used to model eddy-current probes with ferrite cores, or it can be used to compute flaw-field interactions. Both of these problems are of considerable importance in applying electromagnetic techniques to NDE, for they are intimately involved in detecting flaws, and inverting eddy-current data for reconstructing flaws. The model is fully three-dimensional, and the discretized integral equation is solved iteratively using conjugate gradients and FFT techniques. Problems with 12,000 unknowns are being routinely solved on the Alliant FX/ 1 minisupercomputer in reasonable times. The model is used to compute such important probe parameters as impedance and coupling. It is also used to compute the electromagnetic response of flaws as the geometry of the flaw changes, or as a function of frequency. [Vol. 4, No. 1, pp.3-22 (1989)] |
| Author(s): | Harold A. Sabbagh, John R. Bowler, L. David Sabbagh, Harold A. Sabbagh, John R. Bowler, L. David Sabbagh |
| File Type: | Journal Paper |
| Issue: | Volume: 4 Number: 1 Year: 1989 |
| Download Link: | Click here to download PDF File Size: 762 KB |
| Title: | A Uniaxial Time-Domain Wave Potential Analysis of the Electromagnetic Field in Nonuniform Media |
| File Type: | Conference Paper |
| Issue: | Volume: Advanced Computational Techniques for System Design Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 97 KB |
| Title: | A Summary Review on 25 Years of Progress and Future Challenges in FDTD and FETD Techniques |
| Abstract: | The finite-difference time-domain (FDTD) method has established itself among the most popular methods for the numerical solution of Maxwell equations. Reasons for its popularity include its versatility, matrix-free characteristic, ease for parallelization, and low computational complexity. In recent years, the finite-element time-domain (FETD) has also become another very popular algorithm for solving time-domain Maxwell equations due to its geometrical flexibility and the steady growth in hardware computing power. In this review, we succinctly recollect some of the milestones in the development of FDTD and FETD over the last 25 years, and briefly discuss some challenges for the future development of these two algorithms. |
| Author(s): | F. L. Teixeira |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 1 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 274 KB |
| Title: | A ROMANIAN EXPERIENCE IN COMPUTER-AIDED ELECTROMAGNETIC EDUCATION |
| Abstract: | The paper presents the actual interests in computer-aided electromagnetic education (CAEE) at the Electrical Engineering Department from Polytechnic Institute of Bucharest, Romania. The actual state of computer use on different levels of undergraduate and graduate education is presented. Specifically, an overview of the undergraduate theoretical training and practical applications is described, and research topics for graduate reports and doctoral dissertations are discussed. Issues related to hardware utilities are reviewed, and future projects aimed at improving the CAEE capabilities in Romania are described. The material is based on significant selected references. [Vol. 8, No. 1, (1993), Special Issue on Computer Applications in Electromagnetics Education, pp 125-137] |
| Author(s): | Mihaela Morega, Daniel Ioan, Mihaela Morega, Daniel Ioan |
| File Type: | Journal Paper |
| Issue: | Volume: 8 Number: 1 Year: 1993 |
| Download Link: | Click here to download PDF File Size: 748 KB |
| Title: | A Review of Ultra-Wideband Array Antennas |
| File Type: | Conference Paper |
| Issue: | Volume: 7-TA-4 In Celebration of 70th Birthday of Prof. Jia-dong Xu I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 132 KB |
| Title: | A Review of the Modal Decomposition Matrix for Calculating the Far Field of an Infinitely Flanged Rectangular Waveguide |
| Abstract: | We determine the radiation from an infinitely flanged rectangular waveguide using the modal decomposition matrix (MDM) method. The MDM method computes the electromagnetic field components at the aperture in the Fourier domain by representing the radiated field in terms of a sampling of the free-space transverse wave number. The results of the MDM approach show good agreement with numerical approaches using commercial electromagnetic modeling software. |
| Author(s): | G. A. Mitchell, W. Wasykiwskyj |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 12 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1843 KB |
| Title: | A Review of Terahertz Imaging Systems in CMOS |
| File Type: | Conference Paper |
| Issue: | Volume: 3-2-D EM + Active Device Modeling for MMIC and 5G Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 175 KB |
| Title: | A Review of Statistical Methods for Comparing Two Data Sets |
| Abstract: | Statistical approaches to compare data for validation of computational electromagnetics have been used for several years. They provide an accepted means of obtaining a numerical value to quantify the data under consideration. However, the use and meaning of these ‘numbers’ depends, by necessity, on the application. This paper provides an overview of some of the most widely applicable techniques, relating the output of these to visual assessment. It further includes comparison with the FSV (Feature Selective Validation) method allowing a triangulation between statistical approaches, visual approaches and heuristic approaches to validation. It is important that the decision to use or reject a particular technique for validation is based on a rational and objective selection approach. This paper suggests a framework to support this selection approach. |
| Author(s): | A. Duffy, A. Orlandi, A. Duffy, A. Orlandi |
| File Type: | Journal Paper |
| Issue: | Volume: 23 Number: 1 Year: 2008 |
| Download Link: | Click here to download PDF File Size: 165 KB |
| Title: | A Review of Recent Advances in Designing True-Time-Delay Microwave Lenses Exploiting Metamaterials with Non-Resonant Constituting Unit Cells |
| Abstract: | This paper presents a review of recent developments in the design of planar microwave lenses capable of operating over broad bandwidths in a true-time-delay fashion. The lenses discussed in this paper consist of planar apertures populated with miniature, sub-wavelength time-delay units. Each time delay unit is the unit cell of an appropriately-designed Frequency Selective Surface (FSS) with non-resonant, sub-wavelength constituting unit cells and is designed to provide a constant time-delay unit over the frequency range at which the lens operates. Designs that exploit both band-pass and low-pass FSSs are presented and discussed. Because of the non-resonant nature of their constituting unit cells and their small dimensions, such lenses can operate over broad bandwidths with wide fields of views. When used in conjunction with appropriately designed feed antennas, these lenses can be used in multi-beam, high-gain, broadband antenna apertures. |
| Author(s): | N. Behdad |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 12 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 1848 KB |
| Title: | A Review of Perfectly Matched Absorbers for the Finite-Volume Time-Domain Method |
| Abstract: | Different implementations of planar perfectly matched absorbers are studied under the unified framework of the Finite-Volume Time-Domain (FVTD) method. This comparative analysis allows to discuss the similarities existing between the theoretical models and explores the differences in their practical implementation and numerical performance in the framework of the FVTD method. Numerical experiments for performance analysis of the different PML models are conducted in terms of discretization and angle of incidence using waveguide models. The results are compared to theoretically expected values and to the first-order Silver M¨uller absorbing boundary condition. |
| Author(s): | T. Kaufmann, K. Sankaran, C. Fumeaux, R. Vahldieck, T. Kaufmann, K. Sankaran, C. Fumeaux, R. Vahldieck |
| File Type: | Journal Paper |
| Issue: | Volume: 23 Number: 3 Year: 2008 |
| Download Link: | Click here to download PDF File Size: 318 KB |
| Title: | A Review of Path Integral Time Domain Method |
| File Type: | Newsletter Paper |
| Issue: | Volume: 19 Number: 3 Year: 2004 |
| Download Link: | Click here to download PDF File Size: 570 KB |
| Title: | A Review of Advanced Characteristic Mode Theories for Complex Electromagnetic Problems |
| File Type: | Conference Paper |
| Issue: | Volume: 4-1-A Brainstorm for Computational Electromagnetics: What We Have Achieved and What We Will Do II Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 245 KB |
| Title: | A Review and Application of the Finite-Difference Time-Domain Algorithm Applied to the Schrodinger Equation |
| Abstract: | This paper contains a review of the FDTD algorithm as applied to the time-dependent Schrodinger equation, and the basic update equations are derived in their standard form. A simple absorbing boundary condition is formulated and shown to be effective with narrowband wave functions. The stability criterion is derived from a simple, novel perspective and found to give better efficiency than earlier attempts. Finally, the idea of probability current is introduced for the first time and shown how it can be used to radiate new probability into a simulation domain. This removes the need to define an initial-valued wave function, and the concept is demonstrated by measuring the transmission coefficient through a potential barrier. |
| Author(s): | J. R. Nagel |
| File Type: | Journal Paper |
| Issue: | Volume: 24 Number: 1 Year: 2009 |
| Download Link: | Click here to download PDF File Size: 901 KB |
| Title: | A New Closed-Form Expression for Dispersion Characteristics of Fundamental Mode of SIW by Least Squares Method |
| Abstract: | A new and accurate closed-form expression is introduced using least squares method (LSM) to calculate propagation constant of substrate integrated waveguide (SIW) at its fundamental mode of operation. The derived equation is a function of geometrical parameters of the structure and accurately estimates cutoff frequency of the dominant mode. The LSM is used to determine the effective width of the SIW structure. A review and comparisons with recently published simulation and measurement results are also provided, which verify the accuracy of the proposed method. |
| Author(s): | M. GH. Alijani, M. H. Neshati |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 8 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 798 KB |
| Title: | 25 Years of Progress and Future Challenges in Integral Equation Solvers |
| File Type: | Conference Paper |
| Issue: | Volume: 25 Years of Progress and Future Challenges in Applied Computational Electromagnetics I Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 106 KB |
| Title: | 25 Years of Progress and Future Challenges in FDTD/FETD Techniques and Applications |
| File Type: | Conference Paper |
| Issue: | Volume: 25 Years of Progress and Future Challenges in Applied Computational Electromagnetics II Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 297 KB |
| Title: | 25 Years of Progress and Future Challenges in Boundary-Element Based Field-Circuit and Multiphysics Solvers |
| File Type: | Conference Paper |
| Issue: | Volume: 25 Years of Progress and Future Challenges in Applied Computational Electromagnetics II Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 629 KB |
| Title: | Using MATLAB’s Parallel Processing Toolbox for Multi-CPU and Multi-GPU Accelerated FDTD Simulations |
| Abstract: | MATLAB is a good testbed for prototyping new FDTD techniques as it provides quick programming, debugging and visualization capabilities compared to lower level languages such as C or FORTRAN. However, the major disadvantage of using MATLAB is its slow execution. For faster simulations, one should use other programming languages like Fortran or C with CUDA when utilizing graphics processing units. Development of simulation codes using these other programming languages is not as easy as when using MATLAB. Thus the main objective of this paper is to investigate ways to increase the throughput of a fully functional finite difference time domain method coded in MATLAB to be able to simulate practical problems with visualization capabilities in reasonable time. We present simple ways to improve the efficiency of MATLAB simulations using the parallel toolbox along with the multi-core central processing units (CPUs) or the multiple graphics processing units (GPUs). Native and simple MATLAB constructs with no external dependencies or libraries and no expensive or complicated hardware acceleration units are used in the present development. |
| Author(s): | A. J. Weiss, A. Z. Elsherbeni, V. Demir, M. F. Hadi |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 5 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1792 KB |
| Title: | Using MATLAB to Model Inhomogeneous Media in Commercial Computational Electromagnetics Software |
| Abstract: | This paper presents a new method to model inhomogeneous media in commercial electromagnetics software, especially FEKO. In this method, the inhomogeneous medium is fragmented to some homogeneous pieces. If the size of these pieces is chosen correctly, then the electromagnetic behaviors of them and inhomogeneous medium are the same. Since creating these homogeneous pieces in FEKO manually is very difficult and time consuming, MATLAB is employed to create these pieces in FEKO. |
| Author(s): | A. Farahbakhsh, D. Zarifi, A. Abdolali |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 9 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 511 KB |
| Title: | Using MATLAB to Control Commercial Computational Electromagnetics Software |
| Abstract: | This paper provides details on how to use MATLAB to control some commercial electromagnetics software packages. FEKO is an example that can be directly called from MATLAB. Other commercial software, such as CST Microwave Studio and Ansoft HFSS, require a scripting language interface. An example of a design of an inset rectangular patch antenna is presented using a direct call to FEKO and a Visual Basic for Applications interface to CST Microwave Studio are presented. |
| Author(s): | R. L. Haupt, R. L. Haupt |
| File Type: | Journal Paper |
| Issue: | Volume: 23 Number: 1 Year: 2008 |
| Download Link: | Click here to download PDF File Size: 176 KB |
| Title: | Using Logo-Antenna Based RFID Tags forAdvertising |
| File Type: | Conference Paper |
| Issue: | Volume: Modeling of RFID Devices and Systems Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 548 KB |
| Title: | Using Logo-Antenna Based RFID Tags for Advertising |
| File Type: | Conference Paper |
| Issue: | Volume: Student Paper Competition I Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 548 KB |
| Title: | Using Folded Open-Loop Ring Resonator to Design a Common-Mode Suppression and Frequency Adjustable Balun-Bandpass Filter |
| Abstract: | A compact and simple balun-bandpass filter was investigated by using a pair of half-wavelength open-loop ring resonators (OLRRs) and two microstrip lines. The balun-bandpass filter could be designed easily with a different center frequency by changing the path length of OLLRRs. The design methodology was adopted based on EM simulation to obtain these optimally designed parameters of the OLRRs, and microstrip lines and the filters were fabricated on FR4 substrate. The filters with the frequencies of 2.6 GHz and 5.2 GHz were designed to prove the characteristic of frequency adjustable and they were fabricated with the properties of wide bandwidth and low insertion loss. The balun-bandpass filters presented an excellent inband balanced performance with common-mode rejection ratio over than 40 dB and 34 dB in the passbands of 2.6 GHz and 5.2 GHz, respectively. Good correlation was seen between simulation and measurement, and the result showed that first run pass had been achieved in the majority of our design. |
| Author(s): | C.-M. Chen, S.-J. Chang, J.-C. Zheng, J.-C. Liou, C.-F. Yang |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 1 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 691 KB |
| Title: | Using FEKO Software for Analysis of Radiated Electric Field by Power Converters |
| File Type: | Conference Paper |
| Issue: | Volume: FEKO Modeling and Analysis - 2 Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 336 KB |
| Title: | Using FEKO for Electromagnetic Analysis of Carbon-Fiber Composite Structures |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Simulation using FEKO Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 348 KB |
| Title: | Using Electromagnetic Band Gap (EBG) Superstrate Layer to Enhance the Bandwidth and Gain of a Dual Band Microstrip Patch Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: Metamaterial Structures with Application to Guided-Wave Electromagnetics and Antennas Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 182 KB |
| Title: | Using Efficient Model-Based Parameter Estimation for Pole-Free Solutions of Modal Propagation Constants, as Applied to Shielded Planar Structures |
| Abstract: | A fast and efficient adaptive sampling algorithm is applied to model-based parameter estimation of a Method-of-Lines implementation of two- and three-layer shielded planar structures, creating a pole-free function for the calculation of the propagation constants. The technique minimizes the number of characteristic equation evaluations, and hence reduces the computation time by orders of magnitude when compared to methods using the characteristic equation directly. Examples of a shielded microstrip line and a finline structure are shown below. Between 3 and 15 evaluations of the characterisic function are typically required per determination of an imaginary or real zero. |
| Author(s): | Robert Lehmensiek, Petrie Meyer, Robert Lehmensiek, Petrie Meyer |
| File Type: | Journal Paper |
| Issue: | Volume: 16 Number: 1 Year: 2001 |
| Download Link: | Click here to download PDF File Size: 910 KB |
| Title: | Using Circuit Simulation Optimization to Determine the Electrical Properties of Polymeric Composite Materials |
| File Type: | Conference Paper |
| Issue: | Volume: Computational Methods for Nondestructive Evaluation and Materials Characterization Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 168 KB |
| Title: | Using Antenna Measurements in Numerical Solutions |
| File Type: | Conference Paper |
| Issue: | Volume: S16 EM Modeling using FEKO Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 300 KB |
| Title: | NON-INVASIVE ACTIVE THERMOMETRY WITH A MICROWAVE TOMOGRAPHIC SCANNER IN HYPERTHERMIA TREATMENTS |
| Abstract: | In this work the active microwave tomographic imaging of tissue temperature changes induced in deep hyperthermia treatments is studied. The thermal images would allow to monitor and optimize the treatment, increasing its efficacy and avoiding the heating of healthy tissues. As some hyperthermia systems are based on a cylindrical geometry, it is possible to integrate a microwave imaging array in the same structure, providing a non-invasive tool for the monitoring and control. The application of this technique to deep hyperthermia treatments is investigated by numerical simulations and experimentally on two phantoms of thorax and pelvis, using a prototype for microwave tomography recently developed [Jofre et al, 1990]. lVol. 7, No. 2, pp. 121-127 (1992), Special Issue on Bioelectromagnetic Computations] |
| Author(s): | J. J. Mallorqui, A. Broquetas, L. Jofre, A. Cardama, J. J. Mallorqui, A. Broquetas, L. Jofre, A. Cardama |
| File Type: | Journal Paper |
| Issue: | Volume: 7 Number: 2 Year: 1992 |
| Download Link: | Click here to download PDF File Size: 4250 KB |
| Title: | COMPUTATIONAL METHOD FOR POWER LINE MAGNETIC FIELD EVALUATION |
| Abstract: | The paper reports a model for the power line magnetic field evaluation. The obtained results for three different power lines (380 kV double circuit,380 kV single circuit, 220 kV double circuit) was validated with measurement data. Calculated and corresponding measured data were found in good agreement. The influence of geometrical and electrical power line parameters, such as the spatial configuration of the conductors and line phase sequences, is evaluated and discussed. Data on the influence of adjacent line span on the field are also reported. The method can be used for prediction of human exposure in epidemiological studies. [Vol. 7, No. 2, pp. 148-161 (1992), Special Issue on Bioelectromagnetic Computations] |
| Author(s): | Santi Tofani, Giovanni d'Amore, Giancarlo Bonazzola, Giovanni Fiandino, Santi Tofani, Giovanni d'Amore, Giancarlo Bonazzola, Giovanni Fiandino |
| File Type: | Journal Paper |
| Issue: | Volume: 7 Number: 2 Year: 1992 |
| Download Link: | Click here to download PDF File Size: 740 KB |
| Title: | THE APPLICATION OF NESTED DISSECTION TO THE SOLUTION OF A 2.5D ELECTROMAGNETIC PROBLEM |
| Abstract: | We use the method of nested dissection to solve a 2.5D finite difference electromagnetic problem. This method is considered in some detail, and we have found that the expected theoretical run time savings over more common methods are realised in practice. The program has been used to model EM propagation in coal seams with a view to detecting seam disruptions, which can cause a loss of production in longwall mining operations. Various experimental results and a field survey are discussed and we are able to use these results to construct a physically reasonable model which explains the field data. Some further realistics geological structures are modelled and a comparison between our modelling program and several independent methods shows satisfactory agreement. |
| Author(s): | G. H. Smith, P. R. Williamson, K. Vozoff, G. H. Smith, P. R. Williamson, K. Vozoff |
| File Type: | Journal Paper |
| Issue: | Volume: 5 Number: 2 Year: 1990 |
| Download Link: | Click here to download PDF File Size: 1916 KB |
| Title: | FOUR-ELEMENT BEVERAGE ARRAY |
| Abstract: | An experimental four-element high-frequency Beverage antenna array has been devised for tests on medium range and long range ionospheric circuits. The radiation pattern of the experimental array was calculated using Numerical Electromagnetics Code (NEC) and found to be skewed in azimuth. The antenna installation was subsequently modified in accordance with NEC predictions and the desired beam direction was obtained. Measurements confirmed that the NEC predictions were valid. [Vol. 1, No. 1, pp. 15-20 (1986)] |
| Author(s): | D. V. Campbell, P. Cunningham, P. Dubowicz, K. Loffer, D. V. Campbell, P. Cunningham, P. Dubowicz, K. Loffer |
| File Type: | Journal Paper |
| Issue: | Volume: 1 Number: 1 Year: 1986 |
| Download Link: | Click here to download PDF File Size: 368 KB |
| Title: | The application of nested dissection to the solution of a 2.5D electromagnetic problem |
| Abstract: | We use the method of nested dissection to solve a 2.5D finite difference electromagnetic problem. This method is considered in some detail, and we have found that the expected theoretical run time savings over more common methods are realised in practice. The program has been used to model EM propagation in coal seams with a view to detecting seam disruptions, which can cause a loss of production in longwall mining operations. Various experimental results and a field survey are discuessed and we are able to use these results to construct a physically reasonable model which explanes the field data. Some further realistic geological structures are modelled and a comparison between out modelling program and several independent methods show satisfactory agreement. |
| Author(s): | G.H. Smith, P.R. Williamson, K. Vozoff, G.H. Smith, P.R. Williamson, K. Vozoff |
| File Type: | Journal Paper |
| Issue: | Volume: 15 Number: 2 Year: 2000 |
| Download Link: | Click here to download PDF File Size: 1193 KB |
| Title: | Linear Triangles versus Biquadratic Quadrangles in RCS computations |
| Abstract: | |
| Author(s): | A. Herschlein, J. von Hagen, D. Löffler, W. Wiesbeck, A. Herschlein, J. von Hagen, D. Löffler, W. Wiesbeck |
| File Type: | Journal Paper |
| Issue: | Volume: 20 Number: 3 Year: 2005 |
| Download Link: | Click here to download PDF File Size: 965 KB |
| Title: | Digital joint phase and sampling instant synchronisation for UMTS standard |
| File Type: | Conference Paper |
| Issue: | Volume: System Architectures and Analysis Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 187 KB |
| Title: | Characterizing Dispersion in the Enclosed-Space Radio Channel using a Composite Mode Model |
| File Type: | Conference Paper |
| Issue: | Volume: Propagation Channel Characterization Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 1434 KB |
| Title: | Deterministic Channel Modeling and Performance of Monopolarized and Multipolarized MIMO Wireless Channels |
| File Type: | Conference Paper |
| Issue: | Volume: MIMO and Diversity System Characterization Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 153 KB |
| Title: | Real Time Angle of Arrival Estimation for GSM Signals |
| File Type: | Conference Paper |
| Issue: | Volume: Direction of Arrival Estimation Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 553 KB |
| Title: | Active Frequency Selective Surfaces for Antenna Applications Electronically to Control Phase Distribution and Reflective/Transmissive Amplification |
| File Type: | Conference Paper |
| Issue: | Volume: Phased Array and Active Antennas Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 153 KB |
| Title: | Development of Time-Domain Surface Macromodels From Material Measurements |
| File Type: | Conference Paper |
| Issue: | Volume: Advanced EMC Modeling Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 310 KB |
| Title: | Reduction of Sensitivity to Measurement Errors in the Derivation of Equivalent Models of Emission in Numerical Computation |
| Abstract: | In this paper, the accuracy of an equivalent dipole model for representing electromagnetic emissions from printed circuit boards (PCB) is studied. The optimization of nearfield measurement parameters and required PCB parameters for building a numerical model are discussed and their impact on the accuracy of emission predictions is examined. |
| Author(s): | X. Tong, D. W. P. Thomas, A. Nothofer, C. Christopoulos, P. Sewell |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 7 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 1205 KB |
| Title: | Non-linear Dielectrics and Ferrites in ICEPIC |
| File Type: | Conference Paper |
| Issue: | Volume: Multi-Physics Modeling and Simulations Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 679 KB |
| Title: | Application of the Sliding Surface Method with 3D Finite Element Analyses of a Hybrid Magnetic Bearing |
| File Type: | Conference Paper |
| Issue: | Volume: Low-Frequency Computational Electromagnetics Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 1451 KB |
| Title: | A Simplified Analytical Solution for Characterizing Edge Currents Along a Finite Ground Plane |
| File Type: | Conference Paper |
| Issue: | Volume: Modeling and Simulation in Electromagnetic Engineering Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 1222 KB |
| Title: | Extended Scheme using Equivalent Dipoles for Characterizing Edge Currents Along a Finite Ground Plane |
| Abstract: | For the assessment of radiated fields, a simplified analytical solution that approximates the effects of the currents induced at the edges of a finite ground plane is presented. These edge currents are induced by the actual current sources on the plane. This method can be used in characterizing the electromagnetic (EM) emission from any practical PCB and avoids the need for using high-frequency techniques in evaluating effects due to diffraction. |
| Author(s): | C. Obiekezie, D. W. Thomas, A. Nothofer, S. Greedy, L. R. Arnaut, P. Sewell |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 11 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 465 KB |
| Title: | Convex Optimization Based Sidelobe Suppression for Adaptive Beamforming with Subarray Partition |
| Abstract: | This paper proposes a convex optimization based method to suppress sidelobe in adaptive beamforming at subarray level. Usually phase shift rather than amplitude tapering is implemented at element level to maximize signal to noise ratio. Nevertheless, sidelobe control can be realized at subarray level. The proposed approach is realized by adding a constraint minimizing the difference between weights at subarray level and element-level Chebyshev synthesis into the optimal conditions. Compared with penalty function method, simulations show that for a uniform linear array, the proposed method can suppress sidelobe level considerably, especially the lobes close to mainlobe. Furthermore, it is able to produce better shaped main lobe, which is extremely close to the referenced pattern. |
| Author(s): | S. Xiaofeng, X. Jia, Z. Ying, K. Ling |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 1 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 490 KB |
| Title: | A Transparent UWB Antenna with a 5 to 6 GHz Band Notch Using Two Split Ring Resonators |
| Abstract: | A miniaturized thin film transparent ultrawideband (UWB) antenna design with a band notch is presented. A pair of split-ring resonators (SRRs) is placed besides the radiating element to realize the band notch centered at 5.5 GHz. The proposed transparent antenna covers the whole 3.1 to 10.6 GHz UWB frequency band with a notch from 5 to 6 GHz to isolate interferences from wireless local area network (WLAN) and dedicated short-range communication (DSRC) applications. The transparency of this antenna of up to 80% is enabled by the fabrication on a conductive silver coated thin film (AgHT-8). Hence, the proposed transparent antenna is a suitable for UWB home entertainment network (IEEE 1394 over UWB network) for green building applications, where high data rates are required for multimedia transfer. Implementation of the proposed transparent antenna will reduce the space consumption due to its very low thickness and low profile, while at the same time increasing the aesthetic values of the installed wireless system due to its high transparency. |
| Author(s): | M. S. A. Rani, S. K. A. Rahim, P. J. Soh, B. M. Saad, M. I. Sabram, M. F. M. Yusoff |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 11 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 1213 KB |
| Title: | Detection of the Faulty Sensors on Basis of the Pattern Using Symmetrical Structure of Linear Array Antenna |
| Abstract: | In this paper, a simple method is proposed to diagnose the position of the damaged sensors. The position of the damaged sensors is diagnosed on the basis of the null depth level and the number of nulls for the degraded radiation pattern. The method is initiated with tabulation of the array radiation pattern with a single damaged sensor. The corresponding pattern is set as the reference to the radiation pattern of the failed sensors. The tabulated damaged array sensors are compared to a configuration of the assumed damaged sensor. The radiation pattern with deeper null depth level will be the location of the damaged sensor. Moreover, the symmetrical sensor damaged (SSD) technique diagnose the position of damaged sensor, in which on the basis of nulls one can detect the location of damaged sensors. The proposed method diagnoses the location of damaged sensors on the basis of pattern without complex computation as compared to available methods. |
| Author(s): | S. U. Khan, M. K. A. Rahim, N. A. Murad, F. Zubir, O. Ayop, M. F. M. Yusoff, M. R. Hamid, R. Dewan |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 4 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1634 KB |
| Title: | Crucial Parameters and Optimization of High-Speed Bearingless Drives |
| Abstract: | Bearingless drives integrate the functionality of magnetic bearings and an electric machine into a single device. While this integration allows very compact drives offering all advantages of magnetic levitation, the design process becomes significantly more complex. This work deals with the numerous topological and geometric design decisions which need to be taken for such a bearingless drive. Additionally, the definition of suitable optimization targets for the electromagnetic simulation process is outlined. The proposed guidelines generate a complex relationship of different dependencies which is then fed into the MagOpt optimizer for the design of a high speed bearingless disk drive, which allows verifying the optimization results through measurement results from two prototype drives. |
| Author(s): | H. Mitterhofer, S. Silber |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 8 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1876 KB |
| Title: | Ultra-Wideband Six-port Network Constructed by 90° and In-Phase Power Dividers |
| Abstract: | This article proposes a six-port network design with an ultra-wideband operation from 3.1 to 10.6 GHz. The proposed six-port configuration is constructed by two types of power dividers with different phase characteristics of 0° (in-phase) and 90°. The new proposed configuration eliminates one unused port of the conventional six-port. Both components forming the proposed six-port are designed utilizing the microstrip-slot technique to accomplish the designated UWB operating frequency. The six-port is designed via the use of CST Microwave Studio (CST MWS) and realised by applying Rogers TMM4 substrate. Comparable simulated and measured performances are achieved in terms of S-parameters and phase differences between each consecutive port across UWB frequency range. |
| Author(s): | N. Seman, K. H. Yusof, M. H. Jamaluddin, T. A. Rahman |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 5 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1645 KB |
| Title: | Ultra Wideband Power Divider Design Implementing Microstrip with Slotted Ground |
| Abstract: | This article proposes a compact design of a two-section power divider, which operates over an ultra wideband frequency range of 3-11 GHz. The design approach of microtrip with slotline at the ground plane is applied to reduce the size of the circuit and to achieve wide bandwidth coverage. The rectangular slots are implemented at the ground plane, which is positioned symmetrically underneath the second and third arms of each microstrip quarter-wave transformer to reduce its length up to 33.34%. These attributes lead to an easily fabricated 20 mm x 23 mm compact power divider with a reduced size (by 23.33%). The bandwidth performance is improved up to 19.4% compared to a conventional divider. The design is realized by implementing the Rogers TMM4 substrate and simulated by using CST Microwave Studio. The power divider is verified by using a vector network analyzer (VNA). A good agreement between simulation and fabrication is achieved in terms of return loss, isolation and transmission coefficients across the UWB frequency range. |
| Author(s): | N. Seman, K. H. Yusof, M. H. Jamaluddin, T. A. Rahman |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 8 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1840 KB |
| Title: | Ground Penetrating Radar Radargram Filter using Singularity Expansion Method |
| File Type: | Conference Paper |
| Issue: | Volume: S12 Sparse Array Processing and Radar Sensing Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 261 KB |
| Title: | Investigation of Antennas for Car-to-Car Communications |
| File Type: | Conference Paper |
| Issue: | Volume: S17 Computational Electromagnetics, Advanced Algorithms and Emerging Applications/ High Performance Computing in Electromagnetics Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 414 KB |
| Title: | A High Gain Lens-Coupled On-Chip Antenna Module for Miniature-Sized Millimeter-Wave Wireless Transceivers |
| Abstract: | This paper presents high gain and compact Transmit/Receive (TX/RX) integrated antennas in a standard BiCMOS 130nm technology for millimeter-scale millimeter-wave (mm-wave) applications, including high data rate radios and high resolution radars. The proposed TX/RX antenna module utilizes an integrated dipole antenna for the receiver and a slot antenna for the transmitter, placed orthogonally. The achieved gain and radiation efficiency are 5.7dBi and 41.3% for the slot antenna, respectively, and 6dBi and 39% for the dipole antenna. The link budget is improved by 16dB by optimization on the geometry as well as application of a high resistivity hemispheric silicon dielectric lens. |
| Author(s): | M. Moosavifar, D. Wentzloff |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 11 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1640 KB |
| Title: | DOA Estimation in Heteroscedastic Noise with sparse Bayesian Learning |
| Abstract: | We consider direction of arrival (DOA) estimation from long-term observations in a noisy environment. In such an environment the noise source might evolve, causing the stationary models to fail. Therefore a heteroscedastic Gaussian noise model is introduced where the variance can vary across observations and sensors. The source amplitudes are assumed independent zero-mean complex Gaussian distributed with unknown variances (i.e., source powers), leading to stochastic maximum likelihood (ML) DOA estimation. The DOAs are estimated from multisnapshot array data using sparse Bayesian learning (SBL) where the noise is estimated across both sensors and snapshots. |
| Author(s): | P. Gerstoft, C. F. Mecklenbrauker, S. Nannuru, G. Leus |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 11 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1392 KB |
| Title: | Uniaxial Dielectric Waveguide Filter Design Accounting for Losses Using Mode Matching Technique |
| Abstract: | Dielectric filters can provide compact solutions for filter design problems. However, most dielectrics exhibit uniaxial properties, as well as, losses that will undoubtedly affect performance if not accounted for. This paper derives dispersion relations for lossy uniaxial media in dielectric waveguides and also accounts for lossy conducting walls. The waveguide discontinuity problem in the presence of lossy uniaxial media and finite conductivity waveguide walls, is calculated by mode matching technique and the results are applied to a Ka band filter. The design specifications for the proposed filter are a 32.5 GHz center frequency with 6%. Good agreement between simulated and measured results are shown. |
| Author(s): | L. Murphy, J. Mautz, M. Yazdani, E. Arvas, S. Tozin |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 7 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 856 KB |
| Title: | Ultrawide band Negative Refraction Based on Moving Media Concept |
| Abstract: | The anomalous wave propagation in a homogeneous, isotropic and lossless medium that moves with a constant velocity along the axis of a rectangular waveguide; and its interesting properties lead us to the fact that the moving media may be regarded as double negative metamaterial (DNG). In this paper, the correct sign of the permittivity and permeability of an equivalent stationary media, for each TE and TM modes and for both low and high dielectric velocities are investigated and it is shown that this medium acts as a DNG material over specific frequency ranges. |
| Author(s): | A. Jafargholi, A. Jafargholi |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 11 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 665 KB |
| Title: | Ultra-wideband Flexible Implantable Antenna for Wireless Capsule Endoscopy System with Performance Improvement |
| Abstract: | The implantable antenna is an important part of the wireless capsule endoscopy (WCE) system to achieve wireless communication. This paper designed an ultra-wideband flexible implantable antenna for wireless capsule endoscopy system. With a very wide bandwidth, the antenna can completely cover the industrial, scientific, and medical frequency bands (ISM, 2.4-2.48 GHz) and Wireless Medical Telemetry Service (WMTS, 1.395-1.4 GHz). The expanded size of the proposed antenna is 18mm× 10mm× 0.1mm. The conformal technology of the antenna has further reduced the space of the system and achieved miniaturization. The capsule antenna in this paper is a compact planar monopole antenna fed by a coplanar waveguide, and it uses a flexible material as a dielectric substrate to achieve the conformal shape of the antenna. U-shaped ground branch (UGB) and a loaded split ring resonator (SRR) structure were used to further improve the antenna performance. Simulation and measurement results were basically the same. On the premise of radiation safety and miniaturization of the antenna, the ultra-wideband operation of the antenna was realized. This antenna design provided reference value for the design and application of the capsule antenna. |
| Author(s): | Y. Feng, P. Chen, S. Pan, G. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 6 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1325 KB |
| Title: | Ultra Wideband Microwave Ten-Port Reflectometer |
| Abstract: | This paper describes and simulates the Ultra Wideband (UWB) Ten-Port Reflectometer (TPR). It is based on the concept of well-known sixport structure so that numbers of measuring ports are increased to eight in order to improve reliability and accuracy as well. This article presents UWB (2 GHz to 12 GHz) reflectometer using Rectangular Waveguide (RWG). It is proved that increasing numbers of measuring ports leads to improving accuracy and reliability of structure so that each port with corresponding port help to make wideband reflectometer as well as having reliable and robust structure. This prototype of ten-port reflectometer is simulated by Agilent ADS and using RWG that has more bandwidth, less loss and high Q-factor than other common transmission lines, say microstrip, SIW and CPW. |
| Author(s): | A. Askarian, G. Moradi |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 1 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 468 KB |
| Title: | Tunneling of Spoof Surface Plasmon Polaritons through Effective Epsilon-Near-Zero Material |
| File Type: | Conference Paper |
| Issue: | Volume: 2-P2-F Metamaterials Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 516 KB |
| Title: | Tuning of Waveguide Bandstop Filter Properties by Changing the Physical Dimensions of Metamaterial Unit Cell |
| File Type: | Conference Paper |
| Issue: | Volume: Modeling of Metamaterials and Transformation Based Devices Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 605 KB |
| Title: | Tunable Terahertz Plasmon-Induced Transparency in Resonator-Coupled Dirac Semimetal Waveguides |
| Abstract: | The bulk Dirac semimetal (BDS) is an interesting material, similar to graphene, which can dynamically adjust its optical properties via a variation in its Fermi energy or electrical voltage. In this work, a BDS-based plasmonic device, which enables tunable terahertz plasmon-induced transparency, was proposed and designed. By using the finite element method, the surface plasmon polariton and plasmon-induced transparency of this device were systematically investigated. The results demonstrate that the plasmoninduced transparency of such device can be dynamically tuned by varying its Fermi energy. When the Fermi energy changes from 55 meV to 95 meV, the maximum group delay time of the device increases from 13.2 ps to 21 ps. In the case of a cascading device, the maximum group delay time can be further pushed up to 44.57 ps. The influence of the ambient refractive index on the optical properties of the proposed device was also considered and investigated. |
| Author(s): | D. Wang, J. Yang, W. Wang, L. Yuan, X. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 6 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1609 KB |
| Title: | Tunable Bandstop Filter Based on Split Ring Resonators Loaded Coplanar Waveguide |
| Abstract: | In this paper, a novel electrical tunable bandstop filter based on coplanar waveguide (CPW) loaded with split ring resonators (SRRs) is proposed. The unit cell of the bandstop filter is formed by etching single SRR on the CPW back substrate side, and the SRRs can be excited by the CPW slot’s magnetic field. Lumped equivalent circuit models are developed to analyze the frequency responses, and it shows that by loading the common cathode varactor diodes at the split region of the SRR outer ring, the resonant frequency of the bandstop filter can be electronically adjusted by tuning the reverse voltage of the varactor diodes. The prototype with overall size of 26.6 mm ? 50 mm ? 0.508 mm was designed and fabricated to validate the proposed structure. The measured tunable resonant frequency of the fabricated bandstop filter is from 2.19 GHz to 2.31 GHz while a reverse bias voltage is varying from 0 V to 30 V. It also shows that the -10 dB bandwidth is less than 45 MHz. |
| Author(s): | Q. Xiang, Q. Feng, X. Huang |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1138 KB |
| Title: | Triple-Band GCPW Rectifier for Harvesting EM Energy |
| File Type: | Conference Paper |
| Issue: | Volume: 3-3-D Wireless Power Transfer and Harvesting Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 383 KB |
| Title: | Transmission Bandgap of a Two-dimensional Coaxial Bragg Structure with Hybrid Filling Media |
| File Type: | Conference Paper |
| Issue: | Volume: 2-2-C Novel Electromagnetic Metamaterials and Their Applications Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 315 KB |
| Title: | TRANSMISSION AND REFLECTION CHARACTERISTICS OF A CLASS OF MODIFIED COPLANAR WAVEGUIDE STRUCTURES |
| Abstract: | In this paper, several geometries of a class of grounded coplanar waveguide (GCPW) are investigated using the finite difference time domain (FDTD) method, and their losses are computed. A uniform grounded coplanar waveguide (GCPW) structure is used as a reference case for the other non-uniform geometries. First, this reference case is studied. For this case, four geometries are proposed to study the transmission and loss effect of replacing parts of the dielectric substrate with free space. Afterwards, two new geometries are simulated to study the effect of introducing a neck and a gap in the microstrip feeding line, with and without a bridge that connects the two parts of the microstrip feeding line separated with the gap. The effect of adding a PEC cap above the microstrip feeding line, and connecting the two side ground planes, is also studied. The conductor attenuation is studied for the basic GCPW geometry. The power losses are also calculated for the uniform geometries. The line impedance is calculated for all geometries at several points. |
| Author(s): | Abdelnasser. A. Eldek, Atef. Z. Elsherbeni, Charles. E. Smith, Abdelnasser. A. Eldek, Atef. Z. Elsherbeni, Charles. E. Smith |
| File Type: | Journal Paper |
| Issue: | Volume: 17 Number: 2 Year: 2002 |
| Download Link: | Click here to download PDF File Size: 378 KB |
| Title: | THz Square Cross Section Smooth Spline Horns as a Competitive Alternative to Corrugated Horns |
| File Type: | Conference Paper |
| Issue: | Volume: S09 Advances in Electromagnetic Modeling by WIPL-D - I Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 1111 KB |
| Title: | Three-Way Substrate Integrated Waveguide (SIW) Power Divider Design |
| File Type: | Conference Paper |
| Issue: | Volume: S48 Waveguides and Guided Structures II Number: Year: 2016 |
| Download Link: | Login To Download (For Members) File Size: 307 KB |
| Title: | Three-bit Unit-cell with Low Profile for X-Band Linearly Polarized Transmitarrays |
| Abstract: | In this paper, we present a three-bit phase resolution and low profile unit-cell structure for X-band passive transmitarrays. The unit-cell is implemented using four metallic layers printed on two substrates separated by an air gap. The phase shift is achieved by a combination between current flow modification on middle layers and the variation of the size of path elements. Eight unit-cells are optimized to provide eight phase states with a step of 45°. Experimental results are conducted by using WR-90 waveguide to validate the design. These eight unit-cells cover a wide -3 dB transmission bandwidth of 15% and exhibit a low thickness of 0.18λ0. |
| Author(s): | B. D. Nguyen, M. T. Nguyen |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 9 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1891 KB |
| Title: | Theoretical and Experimental Analysis of Rectangular Waveguides with Isotropic Chiral Media |
| File Type: | Conference Paper |
| Issue: | Volume: Poster Sessions 2 Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 238 KB |
| Title: | The Use of Offset Coupled Microstrip Combline Filters for IF Filters Requiring High Selectivity |
| File Type: | Conference Paper |
| Issue: | Volume: EM Simulations Using Sonnet - II Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 820 KB |
| Title: | The Time-Bandwidth Limit in Optical Nanostructures and Its Relation to Nonreciprocity |
| File Type: | Conference Paper |
| Issue: | Volume: S08 Design, Analysis and Applications of EM Metasurfaces I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 105 KB |
| Title: | The Temperature Compensation for TE011 Mode Resonator with Bimetal Material |
| Abstract: | This paper proposes a temperature compensation design for TE011 mode resonator based on multiphysics analysis. The relationship between structure and electrical performance of circular waveguide resonator is specifically analyzed. Furthermore, a novel temperature compensation structure with bimetal material is proposed by using multiphysics analysis. The proposed TE011 mode resonator is fabricated and tested to verify the design method. The temperature drift coefficient of the compensated TE011 mode resonator can be dramatically reduced from 21.387 ppm/°C to 0.93ppm/°C. |
| Author(s): | Q. Wu, J. Zhang, Y. Yang, X. Shi |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1505 KB |
| Title: | The Substrate Integrated Waveguide T-junction Power Divider with Arbitrary Power Dividing Ratio |
| Abstract: | An X-band H-plane wideband substrate- integrated waveguide (SIW) T-junction power divider with unequal-power-division ratio is presented. Several inductive posts are used to have arbitrary power dividing ratio and also to control the phase difference. The position and diameter of these posts tune the power-split ratio and the phase difference in whole bandwidth. Parametric studies have been done to choose the best positions and diameters to get better results. Two different prototypes have been verified the proposed technique. They are designed and fabricated at a center frequency of 11 GHz. The measured input impedance bandwidths are 54% for ?out =3 dB and 45% for ?out =6 dB respectively. |
| Author(s): | A. Piroutiniya, P. Mohammadi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 4 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1267 KB |
| Title: | The Multiresolution Frequency Domain Method for the Efficient Analysis of Ferrite Loaded Waveguides |
| File Type: | Conference Paper |
| Issue: | Volume: Finite Difference Methods: Recent Developments and Applications Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 457 KB |
| Title: | The Design of Planar Slot Arrays Revisited |
| Abstract: | Design procedures for planar waveguide slot arrays have been known and used for years, but the inexperienced designer is often faced with a number of practical problems when trying to implement them, especially in the case of larger arrays consisting of sub-arrays. Some helpful hints concerning the numerical implementation are provided. These include an effective procedure to avoid the necessity of good initial guesses for the unknown dimensions and recommendations for the subdivision of the nonlinear equations into smaller groups. Other practical aspects which are not explicitly defined elsewhere in the literature, are also addressed. |
| Author(s): | J.C. Coetzee, J. Joubert, J.C. Coetzee, J. Joubert |
| File Type: | Journal Paper |
| Issue: | Volume: 15 Number: 1 Year: 2000 |
| Download Link: | Click here to download PDF File Size: 3222 KB |
| Title: | The Design of a High Gain Dual-Polarized Quad-Ridged Circular Horn Antenna for Wideband EMC Test Applications |
| Abstract: | This paper presents the design of a high gain broadband quadruple-ridged circular horn antenna for Electromagnetic Compatibility (EMC) testing. The proposed antenna contains a wideband feed structure as a transition between coaxial line and quad-ridged circular waveguide behind the conical horn antenna. The wideband matching between impedances at the apertures of the feed and the horn is achieved with a tapering at the flare section along the horn length, which is obtained after a detailed investigation of various tapering profiles. The antenna is designed to operate in horizontal and vertical polarizations (dual linear polarization) simultaneously in EMC tests. This implementation is found to present a return loss greater than 10 dB, isolation level higher than 28 dB, high-gain (minimum 13.6 dBi) and low-gain variation of 4.5 dBi within the frequency range of 1-6.75 GHz (6.75:1 bandwidth) at both polarizations, which is a desired feature in radiated emission and immunity tests. |
| Author(s): | B. Solak, M. Secmen, A. Tekin |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2407 KB |
| Title: | The Design of 276 GHz Triple-Push VCO Based on 65nm CMOS Process Using Slow-Wave Effect |
| File Type: | Conference Paper |
| Issue: | Volume: 4-P4-C THz Antenna, Circuit and System Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 269 KB |
| Title: | Suppression of Anisotropic Birefringence in a Rectangular Waveguide |
| File Type: | Conference Paper |
| Issue: | Volume: S45 Electromagnetic Methods for Devices and Applications I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 136 KB |
| Title: | Superformula-Based Compact UWB CPW-Fed-Patch Antenna With and Without Dual Frequency Notches |
| Abstract: | This paper presents two new designs of UWB coplanar waveguide (CPW)-fed-patch antennas operating in the FCC frequency band (3.1-10.6 GHz). The first design uses the superformula to produce a circular patch with sawtooth-like circumference. As compared to a regular circular patch antenna whose diameter is 25 mm, the proposed circular patch has a smaller diameter of 18.2 mm. Moreover, the proposed antenna covers the entire FCC band unlike a regular circular patch of the same radius. The second design introduces two frequency notches at 3.3-3.8 GHz (WiMAX) and 5-5.9 GHz (WLAN) using two arc shaped circular slots etched on the circular patch and a split-ring resonator (SRR) that is placed on the opposite side of the substrate. Measurements and simulations using HFSS show that the return loss is better than 10 dB across the band except at the two notch locations in Design II. Results are also presented for the radiation pattern and peak gain of both designs. Each of the proposed antennas has a compact size of 24 mm x 19 mm on a 1.5 mm Rogers Substrate (epsilon r=3.85). |
| Author(s): | A. A. Omar, S. Naser, M. I. Hussein, N. I. Dib, M. W. Rashad |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 11 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1949 KB |
| Title: | Substrate Integrated Waveguide-Fed Tapered Slot Antenna With Smooth Performance Characteristics Over an Ultra-Wide Bandwidth |
| Abstract: | We present an ultra-wide extended Kband (18 GHz – 30 GHz) planar linear tapered slot antenna (LTSA) design. From a parametric study involving eight designs, the best compromise LTSA is selected in terms of flattest gain and beam width and most symmetric beam width. The design is antipodal with alumina (?r = 10) substrate and fed with substrate integrated waveguide (SIW). Regular corrugations improve cross-polarization, input return loss, and gain. Numerical simulations use finite element analysis and time domain finite integration technique field solvers. The resulting design has half power beam widths (HPBW) of only ± 3.2° and ± 2.5° variation in frequency in the E- and H-planes, respectively. Cross-polarization levels at boresight are 35.7 dB at 18 GHz and 17.4 dB at 30 GHz, return loss is better than -11.7 dB and gain is 9.23 dB with ± 0.40 dB variation with frequency. Alternatively, for imaging systems requiring efficient illumination of a reflector or focusing elements, a second resulting design shows near-perfect beam symmetry with HPBWE/HPBWH = 0.91. These two LTSAs are good candidates for dual-polarization focal plane array feed applications in astronomy imaging. |
| Author(s): | L. S. Locke, J. Bornemann, S. Claude |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 5 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 988 KB |
| Title: | Substrate Integrated Waveguide Microwave Filter Tuning Through Variable-Fidelity Feature Space Optimization |
| File Type: | Conference Paper |
| Issue: | Volume: EM-Simulation-Driven Design: Modeling and Optimization Number: Year: 2014 |
| Download Link: | Login To Download (For Members) File Size: 473 KB |
| Title: | Substrate Integrated Waveguide Antenna at Millimeter Wave for 5G Application |
| Abstract: | This paper presents a dual-band slot antenna using substrate integrated waveguide (SIW) technology at 26 and 28 GHz. High loss is one of the main challenges faced by 5G base station network due to the severe path loss at high frequency. Hence, high gain antennas are required for 5G base station applications to overcome path loss issue. Hence, this work designs a high gain SIW antenna based on slot technology to excite dual-bands with high gain capability. The antenna is designed with two slots shaped to resonate at two different frequencies: 26 and 28 GHz. The antenna is analyzed using CST software and fabricated on Roger RT5880 substrate with permittivity of 2.2 and lost tangent of 0.0009 with thickness of 0.508 mm. The design operates at 26 and 28 GHz with measured reflection coefficients less than -10 dB. Measured high gains of 8 and 8.02 dB are obtained at 26 and 28 GHz, respectively. Overall, the antenna showed good performance that would benefit the fifth-generation applications. |
| Author(s): | Y. M. Hussein, M. K. A. Rahim, N. A. Murad, H. O. Hanoosh, N. B. M. Nadzir |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 4 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 2076 KB |
| Title: | Study, Design and Fabrication of a CPW Fed Compact Monopole Antenna with Circular Polarization for Ultra Wide Band Systems Application |
| Abstract: | A compact circularly polarized square slot antenna (CPSSA) is presented in this paper, which is appropriate for UWB applications requiring high data rate transmission. This antenna operates across 2.8 GHz to 10.8 GHz with an impedance bandwidth (IBW) of 117.6% for VSWR less than or equal to 2. The antenna consists of a trapezoidal shaped radiation patch which is fed through a coplanar waveguide (CPW) and includes two inverted L-shaped ground arms at the two opposite corners of the slot to excite two orthogonal resonant modes for circular-polarization (CP) radiation. Furthermore, two square slits at the two other opposite corners of the slot are applied to enhance its IBW. The antenna exhibits CP bandwidth of 50.5% across 3.7 GHz-6.2 GHz, which is suitable for WLAN, WiMAX and C-bands. In addition, the antenna has a considerably compact volume of 25×25×0.8 mm3. The measured and simulated results confirm the usefulness of the antenna for practical applications. |
| Author(s): | M. Shokri, S. Asiaban, A. Amiri |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 9 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1746 KB |
| Title: | Structural Optimization of an Optical 90 Degree Hybrid Based on a Weaklyguided 4x4 Multimode Interference Coupler Using a Parallelized Real-coded Micro-genetic Algorithm |
| Abstract: | The optimal design of a 4x4 multimode interference (MMI) coupler as an optical 90° hybrid based on a weakly-guided optical waveguide was considered. Seven geometrical parameters of a 4x4 MMI coupler were optimized by a real-coded micro-genetic algorithm, and parallelized using a message-passing interface. The beam-propagation method was used to evaluate the fitness of the MMI coupler in the optimization process. The optimized 4x4 MMI coupler showed a common-mode rejection ratio greater than 28.9 dBe and a phase error less than 2.52° across a wavelength range of 1520 to 1580 nm, which satisfied typical system requirements. The optimization process was executed on a Beowulf-style cluster comprising five identical PCs, and its parallel efficiency was 0.78. |
| Author(s): | T. Yasui, J. Sugisaka, K. Hirayama |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 5 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1566 KB |
| Title: | Spurious Solutions in Fast Frequency Sweeps |
| File Type: | Conference Paper |
| Issue: | Volume: In Tribute To Dr. Zoltan Cendes Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 68 KB |
| Title: | Spoof Surface Plasmons on the Dielectric-loaded Doubly-corrugated Grating for Terahertz Applications |
| File Type: | Conference Paper |
| Issue: | Volume: 1-SP-2 Electromagnetic Characteristics of Complex Media Simulated by Time Domain Method I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 359 KB |
| Title: | Space-Mapping-Enhanced Kriging Surrogates for Accurate Modeling of Microwave Structures |
| File Type: | Conference Paper |
| Issue: | Volume: Optimization Methods for EM Applications Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 1037 KB |
| Title: | Space-Frequency Domain Iterative Method for Modes Analysis of Planar Waveguides |
| Abstract: | We describe a space-frequency domain iterative algorithm to analyze the modes of planar optical waveguides. The one dimensional Maxwell equation was transformed into space-frequency domain by Fourier transform, and became an integral equation which could be solved by an iterative method. For any refractive index profiles, the effective index and mode field distribution are given simultaneously. The numerical result shows that this method is accurate and flexible for planar optical waveguides with any structure. |
| Author(s): | L. Bingxin, Z. Baorong |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 8 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 353 KB |
| Title: | Space Use Radial Line Slot Antenna with Honeycomb Structure |
| File Type: | Conference Paper |
| Issue: | Volume: Student Paper Competition Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 325 KB |
| Title: | SOME EXPERIENCES IN USING NEC2 TO SIMULATE RADIATION FROM SLOTS ON CYLINDERS |
| Abstract: | A numerical method based on use of the NEC2 code has been used to study radiation from a slot in the surface of a conducting cylinder and the results used in a comparison with the eigenfunction series solu-tion. The two cases of an axial and circumferential slot have been taken as representative between them of the more general case of an inclined slot. In the case of a circumferential slot, truncation of the cylin-der to finite length has been found in all cases to lead to numerical and analytic results which are in poor agreement and this has been accounted for with an argument based on the geometrical theory of dif-fraction. However this alone is not enough to explain what is observed with axial slots where, for small cyl-inders, agreement of the two approaches is good but fails for larger cylinders. It is postulated that this is due to excitation of waveguide modes on the inside of the larger cylinders and the result confirmed by clos-ing the ends of the cylinder in the NEC2 model with a system of radial wires, when agreement is again re-stored. |
| Author(s): | S. H. H. Lim, H. E. Green, C. E. Brander, S. H. H. Lim, H. E. Green, C. E. Brander |
| File Type: | Journal Paper |
| Issue: | Volume: 13 Number: 1 Year: 1998 |
| Download Link: | Click here to download PDF File Size: 422 KB |
| Title: | Slotted Waveguide Transitions for Spatial Power Combining |
| File Type: | Conference Paper |
| Issue: | Volume: Posters Session 2 Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 136 KB |
| Title: | Slotted Coaxial Line and Associated Measurement System for Determination of Dielectric Properties of Gas Plasma |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Electromagnetic Modeling by WIPL-D Software Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 1185 KB |
| Title: | Size-Reduced Bandpass Filter Using HMSIW and Modified U-Shaped DGS Slot-Pairs |
| File Type: | Conference Paper |
| Issue: | Volume: S18 Electromagnetic Metamaterials and Metasurfaces Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 203 KB |
| Title: | SIW Rotman Lens with Planar Slot Array Antenna at Ku-band |
| Abstract: | A multi-beam antenna, which is the combination of a Rotman lens and a planar slot array antenna, is designed in this paper. The lens and the slot array are designed for 15.5 to 16.5 GHz frequency range and implemented in the same substrate using SIW structure. The Rotman lens with 7 input ports and 7 output ports are connected to a planar slotted array antenna with 7 waveguides. This multi-beam antenna consists of seven beams at angles of 0°, ±10°, ±20° and ±30° symmetrically. This antenna is designed for terrestrial and satellite applications, where the low cost, low profile and light multi-beam antennas are needed. Simulated and measured results show that the amplitude and phase distributions and scattering parameters of the antenna are in good agreement. In addition, the SLL, HPBW, main beam direction and cross polarization levels of all the radiation patterns are desirable. |
| Author(s): | S. A. Hosseini, Z. H. Firouzeh, M. Maddahali |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 6 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 2116 KB |
| Title: | SIW like Bull-Eye Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: S04 Printed, Flexible and Reconfigurable Antenna Implementations Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 464 KB |
| Title: | SIW Circularly-Polarized Filtering Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: 1-P1-A Student Paper Contest Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 611 KB |
| Title: | Single-, Dual- and Wide-Band Frequency-Reconfigurable Antenna with Annular Ring Slots |
| Abstract: | This paper presents a frequency reconfigurable antenna enabled using a pair of annular ring slots on a coplanar waveguide (CPW) ground plane. Its initial wideband operation mode from 3 GHz to 6 GHz can be reconfigured into six additional modes: a dual–band mode and five single-band modes, with minimum reflection coefficients (S11) of -10 dB. For demonstration and proof-of-concept purposes, metal switches have been used to represent the switches in simulations and measurements. The ON state is emulated using shorted metal switches, whereas the OFF state is emulated using an open. Good agreements are indicated for simulated and measured S11 and radiation patterns. |
| Author(s): | M. C. Lim, S. K. A. Rahim, M. R. Hamid, P. J. Soh, M. I. Sabran, A. A. Eteng, M. R. Ramli |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 11 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 2128 KB |
| Title: | Single Mode Field Derivation and Simulation of a Dual Ridged Waveguide Dual Probe |
| File Type: | Conference Paper |
| Issue: | Volume: S21 EM-Simulation-Driven Design: Modeling and Optmization Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 141 KB |
| Title: | Simulation-Driven Design of Microstrip-to-CPW Transitions Using Variable-Fidelity EM Models |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic-Simulation-Driven-Design: Modeling and Optimization Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 376 KB |
| Title: | Simulation Analysis of Cross Polarization Property of Waveguide Slot |
| File Type: | Conference Paper |
| Issue: | Volume: 5-P-1 Poster Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 291 KB |
| Title: | Signal Propagation Modeling Based on Weighting Coefficients Method in Underground Tunnels |
| Abstract: | The propagation of electromagnetic waves guided in tunnels and mines is an area of scientific study which is hard to model due to multiple reflections on walls and surrounding obstacles. A novel propagation model for underground tunnels based on the weighting sum of the log-distance propagation model, the modified waveguide model and, the far zone propagation model for the ultra-high frequency (UHF) band is proposed in this paper. The propagation model is divided into five regions based on the distance between the transmitter and the receiver. Each region shows a different propagation characteristic and modeled with weighting sum of the base propagation models. Our model was tested in a tunnel with 2 m x 1.5 m cross-section and 250 m length. Measurement results are consistent with the proposed propagation model. |
| Author(s): | Y. Karaca, O. Tamer |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 8 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 2308 KB |
| Title: | Shift-Inverse Technique in TLM-ROM |
| File Type: | Conference Paper |
| Issue: | Volume: Recent Advances in Time Domain Modeling Techniques Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 217 KB |
| Title: | Shielding Effectiveness of Three Dimensional Gratings using the Periodic FDTD Technique and CPML Absorbing Boundary Condition |
| File Type: | Conference Paper |
| Issue: | Volume: Special Session: Electromagnetic Modeling by WIPL-D Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 203 KB |
| Title: | Sensitivity Analysis of the Orthorhombic Design Parameters in the Artificially Biaxially Dielectric Crystal |
| Abstract: | A full-wave modeling and simulation analysis method is presented for performing sensitivity analysis of artificial uniaxial and biaxial crystals previously reported for study with waveguide measurement systems. Small occlusions were machined into bulk dielectric material to impose effectively biaxial material properties. Here, the primary design parameters for orthorhombic occlusions are presented. Using multivariate parameter estimation, the effective material properties are characterized in a way that is equivalent to waveguide measurement methods. The advantage in using full-wave simulation allows investigation beyond measurement and fabrication capabilities, but is still limited because of the mesh size needed to model the fine geometric sizes of the occlusions in the crystal. The analysis shows that the effects of the primary design parameters on anisotropy can achieve 2-3 dB of axial difference for the biaxially diectric crystal. Although, only the dielectric case is presented, the multivariate estimation method used to estimate the material parameters is applicable for characterizing lossy and magnetic materials. |
| Author(s): | J. Brand, M. A. Saville |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 10 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 335 KB |
| Title: | Scattering by Closed and Unclosed Metallic Rings in a Circular Waveguide |
| File Type: | Conference Paper |
| Issue: | Volume: Poster Session Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 383 KB |
| Title: | Scan Blindness Elimination Using Composite Defected Ground Structures and Edge-coupled Split Ring Resonators |
| Abstract: | A novel compact composite structure, composed of double-U shaped defected ground structure (DGS) and edge-coupled split ring resonator (E-SRR), is presented in this paper. The composite structure is integrated into microstrip array to reduce the interelement mutual coupling, with the aim to eliminate the scan blindness and improve the scanning performance. The three kinds of two-element arrays (without composite structure, with only DGS and with composite structure) are thoroughly simulated, measured, and compared. The results show that, the reduction in mutual coupling of 11 dB between elements in E-plane is obtained with the use of composite structure. It is worth mentioning that, approximately 2dB gain improvement and 2.4dB side lobe suppression are both attained, in comparison with the array with only DGSs. Finally, the scan properties of three kinds of infinite microstrip phased arrays are studied by the waveguide simulator method. The results indicate that the scan blindness in an infinite microstrip phased array can be well eliminated by virtue of the effect of the proposed composite structures, in accordance with results obtained by active patterns of the centre element in 9×5 array. |
| Author(s): | M. C. Tang, S. Xiao, C. J. Li, C. Wei, B. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 7 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 1531 KB |
| Title: | Rule for Mode Coupling Efficiency in Optical Waveguide Crossing |
| Abstract: | Crossing an optical waveguide requires a beam coupling from free space to waveguide at the entrance plane and another beam coupling from waveguide to free space at the exit plane of the waveguide. The aim of this paper is to provide a simple rule expressing the relationship between the involved numbers of free and guided modes that efficiently rebuild the field at each end of the waveguide. Using a numerical program built on Maple software, the rule was determined to be effective independently of the ratio between the beam spot size and the waveguide radius. |
| Author(s): | B. Bentouhami, Z. D. Kaddour |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 5 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 2436 KB |
| Title: | Role of Surface Geometric Patterns and Parameters in the Dispersion Relations of Spoof Surface Plasmon Polaritons at Microwave Frequency |
| Abstract: | Spoof surface plasmon polaritons (SSPPs) can be excited using geometric shapes on conducting surfaces in microwave (MW) regime. They are eminent as compared to the conventional microstrip (MS) transmission lines, due to their better efficiency and compactness in high density and high-speed circuitry. In this work, we compare normalized dispersion curves (DCs) of different groove shapes engineered on the planar metallic strip with the variation of geometric parameters of the structure, which are obtained by Eigen-mode solver of ANSYS’s HFSS. It is found the dispersion characteristics are determined by the shape and the asymptotic frequency can finely be tuned through the geometric parameters. All DCs deviate further from the light line indicating slow propagation of SSPPS. The performance of rectangular grooves is clearly outstanding; however, the circular grooves behave comparably better than Vee-groove. Further, a low pass plasmonic filter has been proposed with semicircular gradient subwavelength grooves designed on a planar metallic strip with transition sections to match both the impedance and momentum of MS line and the plasmonic waveguide. Results of S-parameters and magnitude of electric field distributions show excellent transmission efficiency from fast guided wave to slow SSPPs. It is also observed that the confinement of such surface waves is dependent on the geometric parameters which can be useful in plasmonic structure engineering and fine-tuning the cutoff frequencies, hence posing a new prospect for advanced plasmonic integrated devices and circuits. |
| Author(s): | R. S. Anwar, L. Mao, H. Ning |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 1 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2035 KB |
| Title: | Robust and Efficient Model-Order Reduction for Lossless Microwave Structures Using the Impedance Formulation of the Finite Element Method |
| File Type: | Conference Paper |
| Issue: | Volume: S18 Computational Electromagnetics Advanced Algorithms and Emerging Applications I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 248 KB |
| Title: | RF Magnetic Field Profiling with a Dielectric Bore Lining for Traveling Waves in a 3-T MRI Scanner: A Computational Study |
| Abstract: | Traveling-wave magnetic resonance imaging (MRI) can be advantageous over the classical, quasistatic or near-field MRI. However, it is restricted to ultra-high static magnetic fields in the scanner and the correspondingly high RF excitation magnetic field frequencies due to fundamental constraints in cutoff frequencies of the MRI bore, considered as a waveguide. Through a computational study, we propose translating traveling-wave ideas to a 3-tesla scanner, where the RF magnetic field frequency is 127.8 MHz, using a highpermittivity dielectric layer (lining) that is built into the bore. With the lining, we can achieve traveling-wave modes inside the imaging phantoms even at 3 T, where this is generally not possible. We present results obtained using the higher order method of moments in the surface integral equation formulation, previously established as an efficient, accurate, and reliable technique for modeling of RF fields in MRI applications. Our simulations of a simple circularly polarized RF probe and dielectric lining give rise to a considerably uniform circularly polarized RF magnetic field inside phantoms in the clinical scanner. |
| Author(s): | M. M. Ilic, A. A. Tonyushkin, P. S. Athalye, N. J. Sekeljic, A. J.M. Kiruluta, B. M. Notaros |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 3 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1521 KB |
| Title: | Response Sensitivity Analysis with Frequency-Domain Full-Wave Electromagnetic Solvers |
| File Type: | Conference Paper |
| Issue: | Volume: Optimization and Solution of Complex EM problems Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 258 KB |
| Title: | Research of Medical and Industrial Applications of Microwaves Supported by SEMCAD |
| File Type: | Conference Paper |
| Issue: | Volume: SEMCAD X: Recent Modeling Advances for Virtual Prototyping Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 426 KB |
| Title: | Reflection compensation scheme for the efficient and accurate computation of waveguide discontinuities in photonic crystals |
| Abstract: | Abstract—We presented a novel method for the accurate and efficient computation of the reflection and transmission coefficients of waveguide discontinuities within planar photonic crystals (PhCs). This method proposes a novel kind of field source that optimally excites the dominant waveguide mode and mimics procedures that are typically used for the measurement of reflection coefficients. This technique may be applied to arbitrary field simulators working in the frequency domain. The presented reflection compensation scheme is elucidated along the Method of Auxiliary Sources (MAS). In order to verify the results, we compare two test cases with the rigorous connection technique provided by the Multiple Multipole Method (MMP). |
| Author(s): | D. Karkashadze, R. Zaridze , A. Bijamov, D. Karkashadze, R. Zaridze , A. Bijamov |
| File Type: | Journal Paper |
| Issue: | Volume: 19 Number: 1 Year: 2004 |
| Download Link: | Click here to download PDF File Size: 1069 KB |
| Title: | Reducing Power Coupling Loss between Laser Diodes and Planar Optical Waveguides by Using Tapers |
| File Type: | Conference Paper |
| Issue: | Volume: Guided Waves in Non-Standard Media Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 96 KB |
| Title: | Reconfigurable 2×1 CPW-Fed Rectangular Slot Antenna Array (RSAA) Based on Graphene for Wireless Communications |
| Abstract: | This article presents a 2×1 CPW ultra wideband rectangular slot antenna array (UWB-RSAA) with a modified circular slot shape to support a high data rate for wireless communications applications. The proposed antenna array dimensions are 0.7λo×0.8λo×0.064λo at the resonant frequency 1.8 GHz. It is fabricated on Rogers RO4003 substrate and fed by using a coplanar waveguide (CPW). A graphene layer is added on one side of the substrate to realize frequency reconfigurability and improve the array gain. The proposed array acquires -10 dB impedance bandwidth of the RSAA that extends from 1.7 GHz to 2.6 GHz, from 3.2 to 3.8 GHz, and from 5.2 GHz to 7 GHz. The proposed array achieved a realized peak gain of 7.5 dBi at 6.5 GHz at 0 Volt bias with an average gain of 4.5 dBi over the operating band. When the graphene bias is increased to 20 Volt, the antenna bandwidth extends from 1 GHz to 4 GHz and from 5 to 7 GHz with a peak gain of 14 dBi at 3.5 GHz and an average gain of 7.5 dBi. The linearly polarized operation of the proposed array over the operating bands makes it suitable for short-range wireless communications . |
| Author(s): | D. M. Elsheakh, O. M. Dardeer |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 6 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1678 KB |
| Title: | Recent extensions in FEKO: Parallel MLFMM and waveguide excitations |
| File Type: | Conference Paper |
| Issue: | Volume: FEKO Modeling and Analysis - 1 Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 202 KB |
| Title: | Recent Advances in FDTD Modeling of Electromagnetic Wave Propagation in the Ionosphere |
| Abstract: | Finite-Difference Time-Domain (FDTD) modeling of electromagnetic wave propagation in the Earth-ionosphere waveguide has gained significant interest over the past two decades. Initially, FDTD modeling capabilities were largely limited to two-dimensional models assuming a plasma ionosphere (but incapable of accounting for Faraday rotation), or to threedimensional global models assuming a simple, isotropic conductivity profile ionosphere. Two algorithm developments have recently advanced the state-of-the-art in electromagnetic wave calculation capabilities in the ionosphere: (1) A new, three-dimensional efficient FDTD magnetized plasma model. (2) A Stochastic FDTD (S-FDTD) model of magnetized ionospheric plasma. The first capability permits longer-distance, higher frequency and higher altitude propagation studies by greatly reducing the memory requirements and simulation time relative to previous plasma models. The second capability introduces for the first time a way of solving for not only mean electromagnetic field values, but also their variance. This paper provides an overview of these two recent advances. |
| Author(s): | B. T. Nguyen, A. Samimi, J. J. Simpson |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 12 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 516 KB |
| Title: | Recent Advances for the Full-Wave Analysis and Design of Waveguide Filters for Space Applications |
| File Type: | Conference Paper |
| Issue: | Volume: Efficient Microwave Subsystem Design and Optimization Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 253 KB |
| Title: | Recent Advance in Neuro-Transfer Function-Assisted Yield-Driven EM Optimization |
| File Type: | Conference Paper |
| Issue: | Volume: S40 Advanced Optimization of Electromagnetic Structures - III Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 618 KB |
| Title: | Realization of a Sub-harmonic Mixer with a Substrate Integrated Waveguide Filter |
| File Type: | Conference Paper |
| Issue: | Volume: Design and Analysis of Advanced Circuit Architectures Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 373 KB |
| Title: | Ray Tracing Using Shooting-Bouncing Technique to Model Mine Tunnels: Theory and Verification for a PEC Waveguide |
| Abstract: | We present a shooting-bouncing approach to ray-tracing as applied to signal propagation modeling in electrically large waveguides, such as underground mine tunnels at wireless communication frequencies. The method is verified for a dominantmode rectangular metallic waveguide excited by a dipole antenna. |
| Author(s): | B. A. Troksa, C. L. Key, F. B. Kunkel, S. V. Savic, M. M. Ilic, B. M. Notaros |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 2 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1310 KB |
| Title: | Ray Tracing Using Shooting-Bouncing Technique to Model Mine Tunnels: Theory and Verification for a PEC Waveguide |
| File Type: | Conference Paper |
| Issue: | Volume: S14 Numerical Methods for Analysis, Design and Measurement of Antennas I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 652 KB |
| Title: | Protection of Computer Enclosure against Coupled Electromagnetic Interference |
| Abstract: | In this paper some suggested protection methods is proposed to improve the shielding effectiveness of computer enclosures. Slots and holes on the computer enclosure are divided into five types, and the coupled electromagnetic interference (EMI) into the enclosure is computed using the finite-difference time-domain (FDTD) method when each type slot exists. From comparison of both time domain electric field waveform and field distribution in the enclosure, vent array, joint laps, CD-ROM and display are found to be the main ways that the EMI penetrated into the enclosure. To improve the protection of the enclosure, waveguide window is used to replace vent array. Additionally, rivet number is increased, depth of the joint laps is increased and conductive gaskets are filled into the joint laps. From numerical analyses, it can be demonstrated that the suggested methods are efficient to improve shielding effectiveness of the computer enclosure. Some suggested methods are also proposed for the CD-ROM and display protection. |
| Author(s): | R. Xiong, W. Yang, H.-L. Chen, Y.-T. Duan |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2782 KB |
| Title: | PROPAGATION OF VLF RADIATION IN THE EARTH-IONOSPHERE WAVEGUIDE EXCITED BY AN AIRBORNE DUAL TRAILING WIRE ANTENNA |
| Abstract: | Field strength variations produced by an orbiting aircraft dual trailing wire VLF transmitting antenna are investigated. The towplane is assumed to be executing a circular orbit at a constant altitude and speed. A steady-state mechanical model is adopted for determination of the shape of the dual trailing wire antenna. The exact current distribution on this antenna is calculated using the Numerical Electromagnetics Code (NEC) which is based on a method of moments solution of the Electric Field Integral Equation (EFIE). A propagation code developed at the Naval Ocean Systems Center (NOSC) called TWIRE has been modified to be used in conjunction with NEC. This modified version of TWIRE has been called TWIRENEC. The TWIRENEC code uses the current distribution information provided by NEC to determine the dipole moments for a segmented antenna. The wire segmentation geometry and corresponding dipole moments are then used to calculate the electric field strength as a function of distance and azimuth in the earth-ionosphere waveguide. The waveguide can be considered as either horizontally homogeneous or inhomogeneous. It is demonstrated that the periodic variations in field intensity resulting from an orbiting transmitter are a function of receiver position. These periodic variations can range from a small fraction of a dB to several dB depending upon the location of the receiver with respect to the transmitter. A point dipole approximation of the dual trailing wire antenna is suggested for use in the study of VLF radiation excited by an orbiting antenna in the presence of wind shear. The point dipole approximation is applied to estimate the field strength variations caused by a yo-yo oscillation of the transmitting antenna as it orbits. These yo-yo oscillations are characterized in terms of the change in verticality of the point dipole which occurs over one complete orbit. [Vol. 8, No. 2 (1993), pp 72-92] |
| Author(s): | D.H. Werner, J.K. Breakall, R. J. Lunnen, D.H. Werner, J.K. Breakall, R. J. Lunnen |
| File Type: | Journal Paper |
| Issue: | Volume: 8 Number: 2 Year: 1993 |
| Download Link: | Click here to download PDF File Size: 899 KB |
| Title: | Propagation Mode in a V-shaped Silicon Groove Waveguide Embedded with Metal Nanowires |
| File Type: | Conference Paper |
| Issue: | Volume: 9-P-2 Poster Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 275 KB |
| Title: | Powering Sensors in IoT System by Using Compact Seven Band PIFA Rectenna |
| Abstract: | A compact seven band coplanar waveguide fed planar inverted F antenna (PIFA) is presented. The proposed antenna is designed to harvest the ambient radio frequency energy at GSM 900, GSM 1800, LTE band 11 and 7, UMTS 2100, Wi-Fi 2.4, LTE and WIMAX 5.2. The antenna is simulated using 3D electromagnetic simulators CST and HFSS. Moreover, the antenna is fabricated and it is used to measure the indoor RF spectrum in Egypt. A simple AC to DC converter unit is designed by using HSMS 2850 Schottky diode to convert the collected RF energy to DC energy. The antenna and the AC to DC converter are integrated to form the RF energy harvesting system. The maximum measured efficiency obtained at 2.4 GHz is about 63.7%. |
| Author(s): | N. A. Eltresy, D. M. Elsheakh, E. A. Abdallah, H. M. Elhennawy |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 12 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2516 KB |
| Title: | Power Containment of Hybrid Electromagnetic Modes of Cylindrical Dielectric Waveguide |
| File Type: | Conference Paper |
| Issue: | Volume: Numerical Techniques for Electromagnetic Applications Number: Year: 2011 |
| Download Link: | Login To Download (For Members) File Size: 191 KB |
| Title: | Polarization Isolation Characteristics Between Two Center-Feed Single-Layer Waveguide Arrays Arranged Side-by-Side |
| Abstract: | Abstract - The near field coupling between two large alternating-phase fed single-layer waveguide arrays arranged side-by-side is analyzed by the Finite Element Method (FEM) (HFSS). First, the overall reflection as well as the radiation pattern from the array (320 slots and 18.4 λ x 14.9 λ) is analyzed, and excellent agreement with measurements is observed. Next, the isolation between two arrays is computed, and remarkable polarization isolations of more than 80 dB are predicted. The isolation is verified by measurements. The influence of the relative arrangement of the arrays upon the isolation is discussed. |
| Author(s): | Yasuhiro Tsunemitsu, Jiro Hirokawa, Makoto Ando, Yohei Miura, Yasuhiro Kazama, Naohisa Goto, Yasuhiro Tsunemitsu, Jiro Hirokawa, Makoto Ando, Yohei Miura, Yasuhiro Kazama, Naohisa Goto |
| File Type: | Journal Paper |
| Issue: | Volume: 21 Number: 3 Year: 2006 |
| Download Link: | Click here to download PDF File Size: 1538 KB |
| Title: | Planar Metamaterial for Matched Waveguide Termination |
| Abstract: | We present the design, fabrication, and characterization of a novel matched waveguide termination based on planar artificial metamaterial. This matched termination is realized by recent developed planar metamaterial absorber, which can be designed to near-completely absorb the propagating electromagnetic energy at the edge of a shorted rectangular waveguide. Theoretical discussions, numerical simulations and microwave experiments are employed to illustrate the matched characteristics of the proposed waveguide termination. As an example, a matched waveguide termination with standing wave ratio of 1.23 is experimentally demonstrated at microwave frequency. Our result yields a promising approach to design of novel waveguide terminations by techniques of metamaterials. |
| Author(s): | J. Li, F. Wang, G. Wen, Y. Huang, W. Zhu |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 12 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 458 KB |
| Title: | Physics of Wave Propagation in Miniaturized Metamaterial-based Waveguides: Analytical, Numerical and Experimental Investigation |
| File Type: | Conference Paper |
| Issue: | Volume: Metamaterial Structures with Application to Guided-Wave Electromagnetics and Antennas Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 462 KB |
| Title: | Perturbation Approach to Shape Reconstruction in a Rectangular Waveguide using Experimental Data |
| File Type: | Conference Paper |
| Issue: | Volume: S21 Optimization and Inverse Problems in Low-Frequency Electromagnetic Fields Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 558 KB |
| Title: | Performance Optimization of Reconfigurable Reflectarray Antennas |
| File Type: | Conference Paper |
| Issue: | Volume: Latest Developments of Reflect/Transmit Array Antennas Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 657 KB |
| Title: | PERFORMANCE OF THE GENERALIZED MULTIPOLE TECHNIQUE (GMT/MMP) IN ANTENNA DESIGN AND OPTIMIZATION |
| Abstract: | During the last decade, the generalized multipole technique (GMT) has been extensively studied, improved and applied to many electromagnetics problems such as bioelectromagnetics, optics, waveguides and electromagnetic compatibility (EMC), but little has been reported towards utilizing this method for antenna design and optimization. On the other hand, the few published examples of simple dipoles and helices in the close vicinity of lossy scatterers have suggested the potential significance of GMT for antenna design purposes. In this paper, the applicability of the GMT based 3D multiple multipole (3D MMP) code for simulation of wire antenna has been investigated. To evaluate the advantages and limitations of 3D MMP, several basic types of wire antenna configurations were simulated. These were linear and linear array, helical, and physically constrained low profile antennas. To validate the method's performance, we calculated radiation patterns, impedance, return loss, reflection coefficient, VSWR, and compared them to available results from experiments and/or results published by others using different techniques. This investigation showed several conceptual advantages of this technique for antenna simulations. Furthermore, the thin-wire expansion in combination with multipoles and roof top functions provides a great degree of flexibility in modeling. The most recently implemented expansion, "line multipoles," extends the code's efficiency to non-thin-wire configurations (e.g., helix with small ratio of pitch to wire diameter). Critical issues of modeling are the feedpoint and wire tip area, matching point locations and segment length-to- diameter ratio. Symmetries are used where possible to minimize computation time without loss of generality as any antenna element may easily be assembled in non- symmetrical configurations with the block-iterative solver. In order to achieve better confidence on more complex configurations, extensive studies were performed to increase efficiency and stability of modeling and will be discussed. In addition, the numerical validation techniques were extended to satisfy the special requirements of antenna simulations. These studies demonstrate the potential of GMT/MMP for use in analysis, synthesis and optimization of antennas. [Vol. 9, No. 3 (1994), Special Issue on Generalized Multipole Technique (GMT), pp 79-89] |
| Author(s): | Roger Yew-Siow Tay, Niels Kuster, Roger Yew-Siow Tay, Niels Kuster |
| File Type: | Journal Paper |
| Issue: | Volume: 9 Number: 3 Year: 1994 |
| Download Link: | Click here to download PDF File Size: 3160 KB |
| Title: | Particle Swarm Optimization Applied to EM Problems |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Electromagnetic Modeling by WIPL-D Software Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 339 KB |
| Title: | Parametric Model Generation Algorithm for Planar Microwave Structures based on Full–Wave analysis and Design of Experiment |
| File Type: | Conference Paper |
| Issue: | Volume: Time Domain Numerical Modeling Beyond FDTD Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 373 KB |
| Title: | Parametric Design of Open Ended Waveguide Array Feeder with Reflector Antenna for Switchable Cosecant-Squared Pattern |
| Abstract: | This paper presents parametric analysis of two-dimensional (2D) open-ended waveguide array feeder and introduces a modified parabolic reflector antenna structure to obtain electronically switchable radiation patterns. The main motivation of the study is to achieve desired radiation characteristics for naval, air and coastal surveillance radars such as, pencil beam, suppressed side lobes and cosecant-squared pattern shapes. The Analytical Regularization Method (ARM) is used as a fast and accurate predesign tool to compute near and far field radiation characteristics of the feeder and reflector antennas. The numerical procedure is initially verified by the analytical methods and the calculated results are presented for the proposed novel designs. |
| Author(s): | O. M. Yucedag, A. S. Turk |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 8 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 1297 KB |
| Title: | PARALLEL IMPLEMENTATION OF GALERKIN TECHNIQUE IN LARGE SCALE ELECTROMAGNETIC PROBLEMS |
| Abstract: | An intergal equation formulation in conjunction with a palallelised Galerkin technique is employed to solve large-scale electromagnetic (EM) problems. The proposed technique is applicable to EM structures consisting of similar conducting or dielectric parts, defined as "elements". Coupled intergal equations are derived in the frequency domain, written in terms of the conductivity currents or the electric fields deployed on the conducting or dielectric "elements" surfaces, respectively. The system of intergal equations is numerically solved via the parallel computed Galerkin technique, with convienient entire domain basis functions. Even for ellectrically large structures, the use of entire domain basis functions leads to relatively small order linear systems and the main computational cost refers to the matrix fill rather than the matrix solution. The parallalisation introduced to the computation of the matrix elements overcomes the limitation of using Method of Moments at lower and resonant frequencies. The inherent parallelisim of the introduced technique allows for the results to be obtained with minimal addition to sequental code programming effort. Two indicative electromagnetic compatibility applications are presented, concerning the coulping of incident waves with multiple conducting rectangular plates and the coupling phenomena occuring in a multi-element waveguide array looking into a layered lossy cylinder. Numerical results are presented, while the applicability/suitability of diverse High Performance Computing platforms is judged, based on both performance obtained and ease of code portation. |
| Author(s): | D.I. Kaklamani, K.S. Nikita, A. Marsh, D.I. Kaklamani, K.S. Nikita, A. Marsh |
| File Type: | Journal Paper |
| Issue: | Volume: 14 Number: 3 Year: 1999 |
| Download Link: | Click here to download PDF File Size: 808 KB |
| Title: | Padé Boundary Conditions for Finite Element Time Domain Beam Propagation Method |
| File Type: | Conference Paper |
| Issue: | Volume: S52 Novel Photonic Material and Devices II Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 347 KB |
| Title: | Overview of the Latest Additions to FEKO Suite 5.4 Enabling Faster Solutions to a Larger Variety of Electromagnetic Problems |
| File Type: | Conference Paper |
| Issue: | Volume: FEKO Modeling and Analysis I Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 231 KB |
| Title: | Optimum Design of SIW Longitudinal Slot Array Antennas with Specified Radiation Patterns |
| Abstract: | In this paper, an optimum design is presented for substrate integrated waveguide (SIW) longitudinal slot array antennas based on the method of least squares (MLS). Elliott’s design procedure for dielectric filled waveguides is considered, taking into account the internal and external mutual couplings. The MLS error function is a multi-term function based on design goals, including specified radiation patterns and matching of the input impedance. We use the hybrid method of genetic algorithm-conjugate gradient for the error function minimization. This approach is very effective because of combining the “pattern synthesis” with “impedance matching” and “calculation of array parameters”. This procedure increases the speed of design as well as synthesizing patterns with specified characteristics. The MLS design results and those obtained by HFSS and CST simulation software are in good agreement and verify the accuracy of the proposed method. |
| Author(s): | S. E. Hosseininejad, N. Komjani, H. Oraizim, M. T. Noghani |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 4 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 778 KB |
| Title: | Optimized Design of Substrate Integrated Waveguide Cavity based Oscillators |
| File Type: | Conference Paper |
| Issue: | Volume: Efficient Microwave Subsystem Design and Optimization Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 244 KB |
| Title: | Optimization of Aperiodic Waveguide Mode Converters |
| File Type: | Conference Paper |
| Issue: | Volume: CEM for Applied Analysis and Synthesis Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 294 KB |
| Title: | Optimal Design of Photonic Devices Using Time-Domain Beam Propagation Method |
| File Type: | Conference Paper |
| Issue: | Volume: S18 Time-Domain Techniques for Designing Electromagnetic and Optical Devices - I Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 552 KB |
| Title: | Optimal Design of Dielectric Layer PBG Filter Structure in Waveguide by Response Surface Methodology |
| File Type: | Conference Paper |
| Issue: | Volume: Efficient Optimization Techniques for High Frequency Structures Number: Year: 2013 |
| Download Link: | Login To Download (For Members) File Size: 372 KB |
| Title: | Optimal Design of an Ultra-Wideband Antenna with the Irregular Shape on Radiator using Particle Swarm Optimization |
| Abstract: | An ultra-wideband antenna with an irregular shape radiator for ultra-wideband applications has been designed by particle swarm optimization along with the simulator, HFSS. The proposed antenna design process is automated. Also, the better results can be obtained efficiently. The proposed antenna is fed by a coplanar waveguide line. The optimized antenna has a compact substrate size of 34.0 mm by 33.35 mm. Results show that the optimized irregular shape of the proposed antenna outperforms the antennas with uniform rectangular shapes in impedance matching. The optimized antenna can cover the spectrum of ultra-wideband (3.1 GHz - 10.6 GHz). The current distributions are investigated for describing the antenna characteristics. Moreover, the proposed UWB antenna has good characteristics of radiation, transmission, and impedance bandwidth. |
| Author(s): | W. C. Weng |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 5 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 1271 KB |
| Title: | Optimal Design for an Ultra-wideband Antenna Using Particle Swarm Optimization |
| File Type: | Conference Paper |
| Issue: | Volume: Optimization Methods for EM Applications Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 1055 KB |
| Title: | Optical Crosstalk Improvement in Ring Resonator Based Add/Drop Multiplexers Using Controllable Reflectivity |
| Abstract: | In this paper, the topic of optical signal integrity is approached by studying crosstalk suppression in ring resonator based optical Add/Drop Multiplexers (OADM). The resonance splitting induced by surface corrugation is exploited to enhance signal integrity by increasing the crosstalk suppression bandwidth compared to that of a smooth-walled resonator. Sidewall roughness in silicon-on-insulator waveguides is studied using Coupled Mode Theory (time and space domain CMT). An analytical model of a corrugated ring resonator is presented, which is then exploited to estimate the spectral response of the different ports. Verification against results generated from full-wave electromagnetic numerical modeling of a randomized corrugated ring is performed. The analysis then examines the performance of an OADM with controllable reflectivity resulting from a predefined corrugation of sidewall. Gratings have been successfully used in optical filters; this paper proposes the use of a grating in an OADM, giving more controlled roughness. A grating-assisted design of a single ring OADM with 28 GHz crosstalk suppression bandwidth is presented. This bandwidth supports the dropping of 10 Gbps signals with mitigated crosstalk levels and improved signal integrity. |
| Author(s): | R. D. Mansoor, A. P. Duffy |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 10 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2913 KB |
| Title: | ON THE USE OF BIVARIATE SPLINE INTERPOLATION OF SLOT DATA IN THE DESIGN OF SLOTTED WAVEGUIDE ARRAYS |
| Abstract: | Essential to the design process of slotted waveguide arrays is an accurate knowledge of the self-properties of the individual slots. These properties can be computed with sufficient accuracy using moment method codes, which are too computationally intensive to be incorporated into design codes for large arrays. This paper describes an interpolation scheme which provides both sufficiently accurate, and rapid, computation of slot data from a pre-determined database to be viable for use in a slotted waveguide array design code. [Vol. 9, No. 1 (1994), pp 6-9] |
| Author(s): | Derek A. McNamara, Johan Joubert, Derek A. McNamara, Johan Joubert |
| File Type: | Journal Paper |
| Issue: | Volume: 9 Number: 1 Year: 1994 |
| Download Link: | Click here to download PDF File Size: 335 KB |
| Title: | On the Power Containment of Transverse Electromagnetic Modes of Cylindrical Dielectric Waveguide |
| File Type: | Conference Paper |
| Issue: | Volume: Application of Electromagnetic Simulation for Designing and Analysis of Antennas and Radio Propagations Part II Number: Year: 2014 |
| Download Link: | Login To Download (For Members) File Size: 206 KB |
| Title: | On The Capacity of the Waveguide Indoor MIMO Channel |
| File Type: | Conference Paper |
| Issue: | Volume: Poster Sessions 1 Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 86 KB |
| Title: | Numerical Analysis of Parallel Plate Waveguide Loaded with Magnetic Photonic Crystals (MPC\'s) |
| File Type: | Conference Paper |
| Issue: | Volume: Modeling Methods for Metamaterials Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 294 KB |
| Title: | Novel High Performance Low Cost Phase Shifters Design Based on the Ferroelectric Materials Technology Using the WIPL-D Code |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Modeling Using WIPL-D Code(I) Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 174 KB |
| Title: | Novel Compact Substrate Integrated Waveguide Balun Filter and Balanced Filter |
| File Type: | Conference Paper |
| Issue: | Volume: 3-MA-2 Novel Multi-functional Integrated Microwave Circuits and Components Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 392 KB |
| Title: | Novel Broadband Circularly Polarized Monopole Antenna for Multi-communication Systems |
| Abstract: | This paper proposes a novel coplanar waveguide (CPW) fed broadband circularly polarized (CP) monopole antenna, which applies to C-band and various wireless communication systems. The antenna consists of the double circular-shaped patch (DCSP) with square and L-shaped slots, and an improved asymmetric ground plane. The prototype of the designed antenna has been fabricated. The results of the measurement show that the 10-dB impedance bandwidth (ZBW) is 117.8% (2.2–8.5 GHz), the 3-dB axial ratio bandwidth (ARBW) is 62% (4.45–8.45 GHz). |
| Author(s): | H. Chen, Q. Feng, Y. Wen, Q. Fu |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 10 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1257 KB |
| Title: | Nondestructive Clamped-Waveguide Low-loss Material Extraction Technique |
| File Type: | Conference Paper |
| Issue: | Volume: Nondestructive Evaluation and Materials Characterization Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 312 KB |
| Title: | New FEKO Modeling Capabilities: Waveguide Ports with Dielectrics, Fast MLFMM based Near-Field Calculations, Integrated Network Modeling, and Dielectric GO |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Modeling using FEKO – I Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 538 KB |
| Title: | Neural Network Technique Simultaneously Optimizing Antenna Return Loss and Radiation Pattern |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Modeling with QuickWave/Concerto Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 138 KB |
| Title: | Neural Network Inverse Modeling Methods for Fast and Accurate Solution of Electromagnetic Devices |
| File Type: | Conference Paper |
| Issue: | Volume: Microwave Modeling and CAD Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 61 KB |
| Title: | Narrow Band, Sharp Roll-Off Rejection Frequency Selective Surface Based on Substrate Integrated Waveguide |
| Abstract: | In this paper, a novel frequency selective surface which has a narrower passband and sharper rolloff rejection than the other single layer designs, is presented. Also, it has better independency from angle and polarization of incident plane wave. In this design a ring loop is placed on a cylindrical cavity of substrate integrated waveguide (SIW). Because of the most compatibility between loop and the electric fields of cylindrical cavity, minimum insertion loss and narrow passband are achieved. |
| Author(s): | M. S. Samani, R. S. Shirazi, G. Moradi |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 7 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 630 KB |
| Title: | Multipactor in Dual-Mode Elliptical Waveguide |
| File Type: | Conference Paper |
| Issue: | Volume: S23 RF/Microwave Electromagnetics - Computational Modeling and Experiments Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 94 KB |
| Title: | Multilayer Half-Mode Substrate Integrated Waveguide Wideband Coupler with High Selectivity |
| Abstract: | A novel 3dB wideband coupler with enhanced selectivity has been proposed and developed in multilayer HMSIW topology. Periodic ginkgo leaf slots (GLS) are etched on top layer of HMSIW to realize a pass-band combining with high-pass characteristics of HMSIW. The novel GLS cells have stop-band characteristics aiming to improve the frequency selectivity and extend the upper stop-band. Moreover, the roll-off at the upper side is very sharper. A continuous coupling slot is etched in the conductor layer at the broadwall of HMSIW. Coupling takes place through the long, offset slot, which features a flexible design providing a wide coupling dynamic range with wideband characteristics. Detailed design process is introduced to synthesize a wideband filtering HMSIW coupler with better stopband rejection. The novel coupler is showing a 34.9% coupling bandwidth at 8.87 GHz with good isolation, reflection and out-of-band rejection performances. Its stop band is from 13.8 to 17.6GHz with the rejection more than 40dB. Good agreement is obtained between the simulated and measured results of the proposed structure. |
| Author(s): | Z. Zhang, Y. Fan, Y. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 9 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1772 KB |
| Title: | Multi-Slot Antenna for Radar Systems |
| File Type: | Conference Paper |
| Issue: | Volume: Recent Antenna Applications Number: Year: 2003 |
| Download Link: | Login To Download (For Members) File Size: 220 KB |
| Title: | Multi-Beams Waveguide Slot Antennas at X-Band for Wireless Communications Systems |
| Abstract: | This paper focuses on the design of a multibeams antenna using waveguide slots technology at Xband. The multi-beams radiation is proposed to expand the coverage of the single antenna, thus more capacity is enabled. Waveguide slots antenna is a well-known antenna for high power and gain transmission capabilities. Therefore, it is preferred. In this work, four variations of waveguide slots antennas are studied. The slot distribution covers one to four broad and narrow walls of the waveguide. This technique enables multibeams patterns. The performance of the proposed antennas is simulated using CST microwave software. The simulated responses of the antennas show that a good matched with return loss greater than 10 dB at the desired frequency. The four proposed antennas achieved a good gain between 6.3 and 7.4 dB with directional beamwidth of 15 degree. The proposed antennas are suitable for implementing in radar applications. |
| Author(s): | H. O. Hanoosh, M. K. A. Rahim, N. A. Murad, Y. M. Hussein |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 7 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1945 KB |
| Title: | Multi-Bandwidth CPW-Fed Open End Square Loop Monopole Antenna for Energy Harvesting |
| Abstract: | Compact CPW-fed open end square loop monopole antenna is presented. The antenna can harvest ambient power at different radio frequencies of 1.8, 1.9, 2.4 and 5.2 GHz. The multi-band coplanar waveguide antenna (MCPW) is designed and fabricated on a very thin and lowprofile substrate. The proposed antenna is used to measure the ambient spectrum in two different places. One of them is indoor and the other is outdoor, in order to see the effect of the place on the proposed energy harvesting system. A multi-band rectifier circuit is designed and integrated with the proposed antenna. The maximum simulation efficiency is 60.98% at 1.9 GHz and -1 dBm input power. The maximum measured efficiency is 60.57% at 2.5 GHz and -1 dBm RF received power. Also, the proposed rectenna has 53.1% measured efficiency at 2.5 GHz and RF received power of -5 dBm. |
| Author(s): | N. Eltresy, D. Elsheakh, E. Abdallah, H. Elhenawy |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 2 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1550 KB |
| Title: | Multi-Bandwidth CPW-Fed Open End Square Loop Monopole Antenna for Energy Harvesting |
| File Type: | Conference Paper |
| Issue: | Volume: S42 Wireless Implants for Biomedical Telemetry II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 289 KB |
| Title: | Modified V-Groove Slot Waveguide for DNA Hybridization Detection |
| Abstract: | Highly sensitive slot waveguides are introduced and studied for DNA hybridization detection. In this investigation, two different configurations based on V-groove silicon on insulator (SOI) waveguides are analyzed using full vectorial finite element method. The suggested designs rely on improving the light confinement through the slot region at an operating wavelength of 1.55 μm. The power confinement, power density (PD), and effective index of the supported modes are studied for the conventional rectangular slot waveguide and proposed designs. Further, the effect of adding a plasmonic layer to the reported slot waveguides is implemented. It has been shown that the plasmonic layer increases the light confinement in the slot region with high potential for DNA hybridization detection with good confinement through the slot region. |
| Author(s): | E. ELDamarawy, A. M. Heikal, S. S. A. Obayya, M. F. O. Hameed |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 7 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 2255 KB |
| Title: | MODIFIED REFLECTIVE SYMMETRIES FOR IMPROVING THE EFFICIENCY OF THE MMP CODES |
| Abstract: | A more general concept for the treatment of symmetry in the 3D MMP codes allows considerable gains in usability. Up to now, symmetry decomposition of functions has been made with functions that are continuous across the symmetry plane. Now discontinuous symmetrizations are added. Possible continuity conditions in the symmetry plane can be enforced explicitly with matching points. Not only are problem sizes reduced, but the creation of good models in the MMP sense is considerably simplified in some common applications. The improved approach also illustrates some of the "classical" methods for calculating obstacles in waveguides. [Vol. 9, No. 3 (1994), Special Issue on Generalized Multipole Technique (GMT), pp 57-62] |
| Author(s): | Fin O. Bomholt, Lars H. Bomholt, Fin O. Bomholt, Lars H. Bomholt |
| File Type: | Journal Paper |
| Issue: | Volume: 9 Number: 3 Year: 1994 |
| Download Link: | Click here to download PDF File Size: 483 KB |
| Title: | Modified Broadband Half Mode Substrate Integrated Waveguide Cruciform Coupler |
| Abstract: | In this paper, a cruciform coupler with Half Mode Substrate Integrated Waveguide (HMSIW) structure is presented. The prototype coupler consists of four half mode SIW structures, which are crossing each other at right angles. Also, two metallic posts are inserted in free section of junction in order to make coupling properties. Compact size and broadband operation are the features of this coupler. The size of coupler is reduced 24% in comparison to previous HMSIW cruciform couplers. A fractional bandwidth of about 35% is obtained. The coupler is designed and simulated by HFSS13. Here, the simulation results are compared with experimental results. |
| Author(s): | Z. Mansouri, M. Kishihara, F. B. Zarrabi, F. Geran |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 11 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 522 KB |
| Title: | Modification of Vivaldi Antenna for 2-18 GHz UWB Application with Substrate Integration Waveguide Structure and Comb Slots |
| Abstract: | In this paper have been developed two new Vivaldi antenna for UWB application at 2-18 GHz with SIW structure for linear phase center labeled as antenna I and antenna II. The proposed antennas have high gain and directional patterns with symmetric radiation pattern in phi=0 and phi=90 planes. The SIW structure is combined with Vivaldi antenna in order to improve the gain, pattern and phase center linearity. Similarly, for gain improvement at lower frequencies for SIW antenna and with less divergence in the gain, slots with comb models are proposed. The prototype antenna is printed and fabricated on Roger 4003 with ?r = 3.45 and thickness of 1.5 mm. The antenna’s total dimension is 120 mm × 160 mm. The simulation and experimental VSWR and the gain of antenna I and II is less than 2.5 and 6 dBi - 15 dBi, and 2.4 for 2.17-18 GHz and 8.2 dBi - 15.5 dBi in the entire frequency range of 2-18 GHz respectively. Likewise, the Vivaldi antenna phase center is investigated and finally the linear characteristic of the antenna phase center is presented with linear variation. |
| Author(s): | F. B. Zarrabi, N. P. Gandji, R. Ahmadian, H. Kuhestani, Z. Mansouri |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 8 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 951 KB |
| Title: | Modelling Nonlinear Photonics Crystal Waveguides Using the Transmission Line Modelling Method |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Transmission-Line Matrix (TLM) Analysis Methods Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 277 KB |
| Title: | Modelling and Impact of 3D Print Inaccuracies on the Performance of Circular Waveguide Hybrid Coupler |
| File Type: | Conference Paper |
| Issue: | Volume: S22 Advances in Hybrid Material Additive Manufacturing of Antennas Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 445 KB |
| Title: | Modelling and Impact of 3D Print Inaccuracies on the Performance of Circular Waveguide Hybrid Coupler |
| Abstract: | Circular waveguide hybrid coupler operating over a frequency range of ISM 57-64 GHz, additively printed and metal plated using electroless technique is introduced. Effects of orientation of print and thickness of intricate structures on the performance of circular waveguide hybrid coupler are presented. The structure is printed using commercially available stereolithographic (SLA) printer. Circulatory system operated by a peristaltic pump is used for selective silver deposition of the hybrid coupler. |
| Author(s): | A. Bal, G. H. Huff |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 11 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1420 KB |
| Title: | Modeling the RF Performance of a Small Array |
| Abstract: | ABSTRACT - Large phased arrays can be reasonably accurately modelled in finite element programs, such as HFSS using an infinite array model of the embedded element. This approximation is not applicable to small arrays, where each element is in a different electromagnetic environment. Very small arrays of simple elements (of about 10 elements or less) can be modelled as a complete unit, but slightly larger or more complex arrays require additional techniques to be modelled accurately. The predicted performance of several versions of a small array has been compared using HFSS V9.5. The arrays contained either waveguide or printed dipole elements and, within the limits of available computing resources, solutions were generated for (1) complete array models, (2) half and quarter array models with symmetry planes, and (3) infinite array models. |
| Author(s): | P. Foster, A. Wicks, P. Foster, A. Wicks |
| File Type: | Journal Paper |
| Issue: | Volume: 21 Number: 3 Year: 2006 |
| Download Link: | Click here to download PDF File Size: 366 KB |
| Title: | Modeling of Photonic Waveguide for Biosensing |
| File Type: | Conference Paper |
| Issue: | Volume: Low Frequency Applications - 2 Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 196 KB |
| Title: | Modeling Nonlinear Interactions Between RF And Optical Fields In Traveling Wave Modulators Using A Hybrid Approach |
| File Type: | Conference Paper |
| Issue: | Volume: New Techniques for Computational Electromagnetic Validation Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 302 KB |
| Title: | Modeling and Realization of Cavity-Backed Dual Band SIW Antenna |
| Abstract: | Herein, substrate integrated waveguide technology is applied in order to design high performance dual-band microstrip patch antennas. Two microstrip patch antenna designs were studied and modeled in 3D electromagnetic simulators. The obtained optimal models were then realized and measured. The measurement performance of the proposed antenna designs were then measured for 2.4 and 5.6 GHz. The results suggest that the proposed model consisting of a modified microstrip cavity-backed antenna and a defected ground structure is a high performance and low cost solution for 2.4 and 5.6 GHz applications. |
| Author(s): | M. A. Belen, P. Mahouti, A. Caliskan, A. Belen |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 11 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1822 KB |
| Title: | Modeling and Analysis of a Dual-Band Dual-Polarization Radiator Using FEKO |
| File Type: | Conference Paper |
| Issue: | Volume: FEKO Modeling and Analysis - 1 Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 200 KB |
| Title: | Model Validation for a Waveguide Septum Polarizer |
| File Type: | Conference Paper |
| Issue: | Volume: FEKO Modeling and Analysis III Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 734 KB |
| Title: | Mode-Selective Corrugated Substrate Integrated Waveguide: A New SIW Transmission Line |
| File Type: | Conference Paper |
| Issue: | Volume: 6-ME-2 Broadband and Multiband RF Circuits II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 313 KB |
| Title: | Mode Conversion Caused by Bending in Photonic Subwavelength Waveguides |
| Abstract: | We study the propagation of light in a subwavelength planar waveguide with an angular bend. We observe the mode conversion of a guided wave with a symmetric beam profile impinging into the bending of a waveguide. The guided wave outgoing from the bend is a mixed set of symmetric and asymmetric modes. The amount of mode conversion through the bend is quantified by calculating the Fourier transform of the electric field profile. It is found that the conversion rate is a function of the bending angle. |
| Author(s): | Y. J. Rodriguez-Viveros, D. Moctezuma-Enriquez, P. Castro-Garay, B. Manzanares-Martinez, C. I. Ham-Rodriguez, E. Urrutia-Banuelos, J. Manzanares-Martinez |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 12 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 708 KB |
| Title: | Mode Analysis of Waveguides in Layered Media |
| File Type: | Conference Paper |
| Issue: | Volume: S47 Integral Equation Solvers for Real-Life Applications I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 255 KB |
| Title: | Modal Analysis of Wave Propagation in Straight and Curved Arched Tunnel Based on Equivalent Rectangular Tunnel Model |
| Abstract: | In this paper, a model is presented to simulate wave propagation in straight and curved tunnels with arched cross section with imperfectly conducting walls. The model is based on treating the tunnels as a rectangular waveguide with imperfectly conducting walls, where the arched cross section of the tunnels is approximated with equivalent rectangular cross section. A scenario is considered to check the accuracy of this model. This scenario is verified by comparing experimental and numerical simulation results. Good agreement between the proposed model and the experimental results is obtained. |
| Author(s): | H. M. El-Maghrabi, S. F. Mahmoud, M. El-Said |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 9 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1770 KB |
| Title: | Modal Analysis for a Waveguide of Nanorods Using the Field Computation for a Chain of Finite Length |
| Abstract: | The propagation of light along an infinite 2D chain of silver nanorods is analyzed and the dispersion for this waveguide is computed using field computation for a finite chain of nanorods. In this work, generalized multipole technique is used for the analysis. This method calculates the imaginary and real parts of the propagation constant by exciting the chain in one end and observing propagation of modes along the chain far enough from the excitation. It is shown that a short chain of finite length is sufficient for the calculation of the phase constant while the attenuation constant requires a longer chain. Field distribution is depicted for even and odd modes and it is shown that in the simulated frequency range only two modes can be excited and can propagate along the waveguide. |
| Author(s): | Y. Rahbarihagh, F. Kalhor, J. Rashed-Mohassel, M. Shahabadi |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 2 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 2114 KB |
| Title: | Microwave/Millimeter Wave Metamaterial Development Using the Design of Experiments Technique |
| File Type: | Conference Paper |
| Issue: | Volume: Metamaterials Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 140 KB |
| Title: | Method of Moments Solution of Closed Chirowaveguides |
| File Type: | Conference Paper |
| Issue: | Volume: Guided Waves in Non-Standard Media Number: Year: 2008 |
| Download Link: | Login To Download (For Members) File Size: 169 KB |
| Title: | Method of Moments (MoM) Modeling of Wave Propagation Inside a Wedge |
| Abstract: | Method of Moments (MoM) is used to model guided wave propagation inside a nonpenetrable wedge waveguide and the results are validated against analytical mode-based exact solutions. |
| Author(s): | G. Apaydin, L. Sevgi |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 8 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 884 KB |
| Title: | Method of Moments (MoM) Modeling for Resonating Structures: Propagation inside a Parallel Plate Waveguide |
| Abstract: | Method of Moments (MoM) modeling inside resonating structures is discussed and a novel approach called Multi-MoM (Mi-MoM) is proposed. Propagation inside a two-dimensional (2D) non-penetrable parallel plate waveguide is taken into account. The Mi-MoM results are compared with the analytical reference solution. Practical ways of different source representations (untilted/tilted Gaussian beams) are also presented. Finally, surface irregularities inside the waveguide and their effects on the propagation are modeled with both Mi-MoM and the Split-Step Parabolic Equation (SSPE) method. |
| Author(s): | G. Apaydin, L. Sevgi |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 10 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 2721 KB |
| Title: | Measurement of Electromagnetic Parameters Based on Gap-Waveguide Structure |
| File Type: | Conference Paper |
| Issue: | Volume: 1-SP-4 Metasurfaces/Metamaterials Theory, Design and Applications I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 574 KB |
| Title: | Mathieu functions of complex arguments and thier applications to the scattering by lossy elliptic cylinders |
| Abstract: | The aim of this paper is to outline the theory for calculating the angular and radial Mathieu functions of complex arguments. These functions are required for the computation of analytic solutions of electromagnetic scattering by lossy dielectric elliptic cylinders and waveguides. The backscattered echo width of a lossy dielectric elliptic cylinder is compared with the special case of lossy circular and weakly lossy elliptic cylinders and excellent agreement is obtained in all cases. Tabulated and plotted numerical results of Mathieu functions are presented. |
| Author(s): | Abdul-kadir Hamid, M.I. Hussein, H. A. Ragheb, M. Hamid, Abdul-kadir Hamid, M.I. Hussein, H. A. Ragheb, M. Hamid |
| File Type: | Journal Paper |
| Issue: | Volume: 17 Number: 3 Year: 2002 |
| Download Link: | Click here to download PDF File Size: 391 KB |
| Title: | Manipulation of Electromagnetic Waves Based on New Unique Metamaterials: Theory & Applications |
| Abstract: | Metamaterials are typically engineered by arranging a set of unit cells in a regular array throughout a region of space, thus, obtaining some desirable macroscopic electromagnetic behavior. The desired property is often one that is not normally found naturally (negative refractive index, near-zero index, etc.). Over the past few years, the flexibilities of the metamaterials in choosing the numerical value of the effective permittivity or permeability have led to kinds of novel theoretical and practical possibilities for different applications, ranging from microwave to optical regime. In this paper, the theoretical mechanism for constructing metamaterials is described, and the unique feature of electromagnetic waves can be manipulated is verified by their applicability to construct various devices or components Some typical application is given, including: (1) novel RF devices realized by optical transformation principle, such as energy concentrators and universal waveguide connectors; (2) metamaterial-based wave absorbers; (3) gain enhancement approach of aperture antennas by planar metamaterial lenses loaded; (4) ultra-thin lenses with dual-polarization filtering features; and (5) beam tunable antennas by metamaterial device. Undoubtely, the reported results suggest promising applications in the next-generation communication system. |
| Author(s): | Q. Qu, K. Zhang, G. H. Yang |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 12 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 2466 KB |
| Title: | Low-cost Two-layer Terahertz Transmitarray |
| File Type: | Conference Paper |
| Issue: | Volume: 2-2-B Millimeter Wave and Terahertz Antennas Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 264 KB |
| Title: | Low Sidelobe Leaky Wave Antenna Based on Gap Waveguide Technology |
| File Type: | Conference Paper |
| Issue: | Volume: 4-P4-D Millimeter-Wave GAP Waveguide Technology Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 382 KB |
| Title: | Low Side-Lobe Substrate Integrated Cavity Antenna Array Using Unequal Microstrip-Ridge Gap Waveguide Feeding Network at 94 GHz |
| File Type: | Conference Paper |
| Issue: | Volume: 4-P4-D Millimeter-Wave GAP Waveguide Technology Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 975 KB |
| Title: | Low Frequency Signal Generation during Fano Resonance Build-up Process |
| File Type: | Conference Paper |
| Issue: | Volume: S31 Electromagnetic/Thermal Modeling of Infrared/Optical Antennas Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 520 KB |
| Title: | Loss Analysis of Wideband RF MEMS Shunt Capacitive Switch in T and Pi-Match Configurations |
| Abstract: | A wide bandwidth coplanar-waveguide (CPW) based RF MEMS capacitive shunt switch with pi-matched & T-matched having high impedance transmission lines is designed and simulated for broadband (18-40 GHz) application. The effects of variation in membrane width (50 & 70 mu m) of the switch and high-impedance transmission line length (300 – 600 mu m) between the switch structures on scattering parameters are studied. The variation in beam width has very little effect on return loss of the switch in up-state. The reduction in high-impedance transmission line length yields marginal improvement in return loss. In the down-state configuration, the return loss showed negligible change with the variation in beam width and high-impedance transmission line length. The isolation is found improved with the increase in beam width and high-impedance transmission line length in whole frequency range. Simulating the technical performance demonstrates the greater improvement in RF characteristics of the switch particularly in return loss in up-state position. In order to validate the obtained result, Artificial Neural Network (ANN) has been trained using ADS result. Comparison shows good agreement between ADS and ANN results. |
| Author(s): | S. Suganthi, P. Thiruvalar Selvan, S. Raghavan |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1832 KB |
| Title: | Localized Plasmonic Enhanced Waveguide Modulator with High Speed Tunability Using Graphene |
| File Type: | Conference Paper |
| Issue: | Volume: 3-MA-4 EM Characteristic and Application of Graphene Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 424 KB |
| Title: | Liquid Crystal-Based Dielectric-Loaded Plasmonic Ring Resonator Filter |
| Abstract: | A new tunable plasmonic filter based on liquid crystal dielectric loaded plasmonic waveguide is proposed and studied. |
| Author(s): | S. M. Alavi, H. Armand |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 2 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 697 KB |
| Title: | LF Sky Wave Propagation Excited by a Horizontal Electric Dipole Towards Understanding of Its Radiation Mechanism |
| Abstract: | In this paper, the electromagnetic pulses have been investigated based on the theory of wave-hop propagation. The approximate formulas are obtained for the electromagnetic field of a vertical magnetic dipole in the presence of an Earth-ionosphere waveguide. Based on the results obtained, the approximate formulas are derived readily for the ground wave and sky waves due to horizontal electric dipole excitation by using a reciprocity theorem. The corresponding computations and discussions are carried out specifically by analogy with those generated by a vertical electric dipole with the formulas in CCIR’s recommendation. It is shown that the sky wave pulses would interfere at certain distances and occur by different time-delays. |
| Author(s): | H. Xu, T. Gu, J. Zheng, K. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 6 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2695 KB |
| Title: | Late-time Instability in Finite Difference Modeling of Very-Low-Frequency Propagation in the Earth-Ionosphere Waveguide |
| File Type: | Conference Paper |
| Issue: | Volume: S39 Modeling Electromagnetic Waves in Plasma Environments Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 1677 KB |
| Title: | Large Waveguide Slotted Array With Shaped Patterns |
| File Type: | Conference Paper |
| Issue: | Volume: S36 Antennas and Arrays Number: Year: 2019 |
| Download Link: | Login To Download (For Members) File Size: 290 KB |
| Title: | Ka-band Planar H-plane Horn Array with Reduced Sidelobe Level |
| File Type: | Conference Paper |
| Issue: | Volume: 2-SE-1 Antennas for mmWave/THz and 5G Communications II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 499 KB |
| Title: | Ka-band Planar H-plane Horn Antenna Based on the Concept of Complementary Source |
| File Type: | Conference Paper |
| Issue: | Volume: 1-P1-A Student Paper Contest Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 203 KB |
| Title: | Investigations on Corrugation Issues in SIW based Antipodal Linear Tapered Slot Antenna for Wireless Networks at 60 GHz |
| Abstract: | In recent days, substrate integrated waveguide (SIW) technology is attracting a lot of interest in the development of millimeter-wave (MmW) based circuits due to its inherent advantages. Tapered slot antenna (TSA) with antipodal geometry is used to surmount the impedance matching constraint and to enhance electrical performance including gain, side lobes levels, and main beam pattern. This paper focuses on the design of antipodal linear tapered slot antenna (ALTSA) using SIW technique at 60 GHz for wireless local area network (WLAN) and wireless personal area network (WPAN) applications. The size of the proposed antenna is very compact (43.29 mm × 9.93 mm × 0.381 mm) and the substrate used is RT/ Duroid 5880. Corrugations have been investigated on both the edges to improve antenna gain, front-to-back ratio, and radiation patterns. Numerical simulations are performed using 3D-EM tools, high frequency structure simulator (HFSS) and CST microwave studio (CST MWS). The obtained results reveal that when corrugation is introduced in the antenna there is a significant improvement of 3 dB in gain, respectively. This study has been reported earlier in other frequency bands but rarely any literature has been reported of such development at 60 GHz. |
| Author(s): | P. Shrivastava, D. Chandra, N. Tiwari, T. Rama Rao |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 10 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 4334 KB |
| Title: | Investigation of an Explicit, Residual-Based, a Posteriori Error Indicator for the Adaptive Finite Element Analysis of Waveguide Structures |
| Abstract: | The performance of an explicit, residual-based, a posteriori error indicator for directing a single level p-refinement of the finite element method, electromagnetic analysis of multiport waveguide structures is evaluated experimentally by considering three different structures. The error indicator consists of a linear combination of element volume and element face residuals. It is found that the indicator is generally very effective in identifying elements that need to be refined. It is also found that the relative weighting of the volume and face residual contributions to the error indicator plays an important role in its performance. |
| Author(s): | Matthys M. Botha, David B. Davidson, Matthys M. Botha, David B. Davidson |
| File Type: | Journal Paper |
| Issue: | Volume: 21 Number: 1 Year: 2006 |
| Download Link: | Click here to download PDF File Size: 251 KB |
| Title: | Integrated Simulation and Analysis of Super Large Slotted Waveguide Array |
| Abstract: | Aiming at the simulation problem of the super large slotted waveguide array antenna, the parallel higher-order method of moment is used and the coupling effect between each slot element is taken into account to perform the integrated and accurate simulation. In order to ensure that the algorithm is efficient and stable in the parallel process, the BDPLU strategy is introduced to reduce the communication pressure and eliminates the redundant communication of the equation solving when pivoting, which speeds up the process of matrix equation solving. According to different types of waveguide port forms, the computation of rectangular wave port and coaxial wave port is studied, and a new parallel matrix filling technique of wave port is used to accelerate the matrix filling process. Numerical examples calculated at "Tianhe-2" supercomputer show that the algorithm can efficiently and accurately handle the simulation analysis of most types of complex slotted waveguide array. |
| Author(s): | C. Zhai, Y. Liu, S. Jiang, Z. Lin, X. Zhao |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 7 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1839 KB |
| Title: | Integrated Disc-loaded Monopole Array Antenna and the Small PIFA Antennas |
| File Type: | Conference Paper |
| Issue: | Volume: Analysis and Design of Antennas for Wireless Communications Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 263 KB |
| Title: | Integral equation formulation for the impedance representation of aperture-coupled devices with finite wall conductivity |
| File Type: | Conference Paper |
| Issue: | Volume: Special Session: Recent Electromagnetics & Antennas Activities in the European Network "ACE" Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 326 KB |
| Title: | Indoor Wave Propagation Prediction for Corridors Segments with Partially Reflecting Walls by Using 3D Waveguide Modal Analysis |
| Abstract: | In this paper, a model is presented to simulate wave propagation in indoor corridors with partially reflecting walls. The model is based on combination of modal analysis, dyadic Green’s function, mode matching method and generalized scattering matrix. A new approach to simulate the effect of partial reflectivity of the walls of the waveguide model is proposed. This approach is based on approximating the fields inside the space of the actual waveguide section by equivalent waveguide sections of larger dimensions with PEC (Perfect Electric Conductor) walls. A simple scenario is considered in order to check the accuracy of this model. This scenario is verified by comparing experimental and numerical simulation results. The obtained results show that the proposed model is suitable for predicting accurate electric field strength due to an electromagnetic source in an indoor environment with partially reflecting boundaries. |
| Author(s): | H. M. El-Maghrabi, A. M. Attiya, E. A. Hashish |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 3 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 871 KB |
| Title: | IMPROVED MODELING OF SHARP ZONES IN RESONANT PROBLEMS WITH THE TLM METHOD |
| Abstract: | Several new modified nodes based on the symmetrical condensed node with stubs are proposed to solve the difficulty of the TLM method in modeling problems highly dependent on frequency. These nodes avoid the problem of indirect modeling at critical points, such as bends and corners, thus providing more accurate results and flexibility in the modeling of conducting parts. The new nodes are applied to specific problems of rectangular waveguides loaded with rectangular irises of finite width to verify their capability to predict resonant phenomena. |
| Author(s): | J. A. Morente, J.A. Porti, H. Magan, O. Torres, J. A. Morente, J.A. Porti, H. Magan, O. Torres |
| File Type: | Journal Paper |
| Issue: | Volume: 14 Number: 2 Year: 1999 |
| Download Link: | Click here to download PDF File Size: 413 KB |
| Title: | Improved Heating Uniformity of a 3-kWatt 2.45GHz Microwave Dryer Using Multiple Multi-Slotted Waveguides |
| File Type: | Conference Paper |
| Issue: | Volume: S26 Advances on Time Domain Modeling and Design II Number: Year: 2019 |
| Download Link: | Login To Download (For Members) File Size: 352 KB |
| Title: | Hyperthermia treatment modeling: is prescriptive, quantitative SAR dosimetry to be preferred over thermal dosimetry? |
| File Type: | Conference Paper |
| Issue: | Volume: Computational RF and Thermal Dosimetry Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 192 KB |
| Title: | Hyperthermia Study in Cancer Treatment |
| File Type: | Conference Paper |
| Issue: | Volume: S52 Biomedical Applications Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 351 KB |
| Title: | Hybrid Plasmonic Waveguiding Model in a V-shaped Silicon Groove |
| Abstract: | A modified V-shaped silicon groove waveguide, embeded with metal nanowire,which is coated with a low refractive index layer was proposed. Finite element method (FEM) is used to numerically simulate the characteristics of the hybrid plasmonic mode at the wavelength of 1550nm. The simulation results show that the hybrid plasmonic mode can be confined to the dielectric layer on the surface of the metal nanowire. Meanwhile, factors on the modal properties are analyzed. Low loss and strong mode confinement can be realized by adjusting the size of the dielectric and metal nanowires as well as the angle of the V-shaped groove. The overall performance of the proposed model is superior to that of traditional hybrid plasmonic waveguides. |
| Author(s): | X.-J. Kuang, Z.-X. Huang, X.-Y. Cao, M. Kong, J. Shen, X.-L. Wu |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 6 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1668 KB |
| Title: | Hybrid of Moment Method and Mode Matching Technique for Full-Wave Analysis of SIW Circuits |
| Abstract: | In this paper, a full wave analysis of substrate integrated waveguide (SIW) structures is presented based on the moment method in combination with the mode matching technique. Initially, input and output post pairs are terminated with two waveguide sections. Then waveguide width, as an unknown variable, is adjusted to obtain minimum reflection from the SIW. Field distribution in the structure and current density on posts as well as dispersion characteristic of the SIW are investigated. Also, by taking the advantage of the moment method, analysis of the structures with longitudinal discontinuity along the wave propagation direction is offered. Furthermore, versatile instances are analyzed and compared with experimental values, results from high frequency structure simulator (HFSS), and numerical methods in recent literature. Good agreement between the results verifies the accuracy of the hybrid method. |
| Author(s): | R. Rezaiesarlak, M. Salehi, E. Mehrshahi |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 8 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 842 KB |
| Title: | Hybrid Nonlinear and Electromagnetic Design of an Active Oscillator SIW Cavity Backed Slot Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: Student Paper Competition Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 623 KB |
| Title: | Hybrid Nonlinear and Electromagnetic Design of an Active Oscillator SIW Cavity Backed Slot Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: Efficient Microwave Subsystem Design and Optimization Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 216 KB |
| Title: | Hybrid Electromagnetic and Non-Linear Modeling and Design of SIW Cavity-Backed Active Antennas |
| Abstract: | This paper presents the modeling and implementation of planar passive and active cavity-backed antennas in substrate integrated waveguide (SIW) technology. The cavity-backed topology helps suppressing the undesired surfacewave modes and may provide better phase noise performance in the antenna oscillator. The use of SIW technology allows for a compact and costeffective implementation of the structure. The design of the active antenna involves both electromagnetic full-wave modeling for the radiating structure and nonlinear analysis of the active circuitry through harmonic balance and transient simulations. Single substrate prototypes of both passive and active antennas operating in X band are presented and measured, showing good agreement with simulated results. |
| Author(s): | F. Giuppi, A. Georgiadis, M. Bozzi, S. Via, A. Collado, L. Perregrini |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 8 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 2673 KB |
| Title: | HMSIW Cavity Filters Employing Various Complementary Split-Ring Resonators for Microwave Remote Sensing Applications |
| Abstract: | In this work, bandpass filters employing half-mode substrate integrated waveguide (HMSIW) cavities and various modified complementary split-ring resonators (CSRRs) are presented. The two modified CSRRs, which are called as Type-I and Type-II CSRRs, can exhibit larger effective inductance and capacitance, and eventually to contribute to the size miniaturization of the resonators. Thereafter, as the two CSRRs are independently loaded into HMSIW cavities, the newlyformed HMSIW-CSRR cavity resonators can achieve more size reduction as compared with the HMSIW cavity with the conventional CSRR. To demonstrate the proposed concept, two HMSIW cavity bandpass filters independently loaded with the proposed Type-I and Type-II CSRRs are implemented. Experimental results shows that measurements of the proposed filters agree with their corresponding simulations well. Meanwhile, as compared with some similar works, the two proposed filters achieve size reduction of 76.8% and 78.6%, respectively, as well as good selectivity, illustrating their suitability for the system integration application in microwave remote sensing and radar systems. |
| Author(s): | L. Wang, Z. He, Y. M. Huang, S. Ding, M. Bozzi |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 9 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1910 KB |
| Title: | Highly Efficient Technique for the Full-Wave Analysis of Circular Waveguide Filters Including Off-Centered Irises |
| Abstract: | A rigorous method for the full-wave analysis and design of waveguide filters implemented in circular waveguide technology, and including offcentered circular irises, is presented. The implemented tool is based on an integral equation technique, which provides a full-wave representation of the elementary blocks of the analyzed components in terms of generalized impedance matrices. With the aim of improving the efficiency of the developed tool, the radial variation of the modal solutions of the circular waveguides has been expressed in terms of sinusoidal functions, thus avoiding the use of the more cumbersome Bessel’s functions employed in the classical formulation. Furthermore, line integrals have been used (instead of surface integrals) to compute the modal coupling coefficients of the planar waveguide junctions involved in the considered filters, thus drastically reducing the CPU effort related to the implemented tool. New designs concerning band-pass filters including off-centered circular irises are also provided. The obtained results show that the relative position of the considered circular irises can be considered as a new design parameter with a noteworthy influence on the electrical response of the investigated components. The accuracy of the proposed method has been successfully validated by comparing the obtained results with data extracted from both the technical literature and a commercial software based on the finite-element method. |
| Author(s): | A. A. San-Blas, J. M. Roca |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 11 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 1074 KB |
| Title: | Higher Order Mode Analysis in WIPL-D A Tutorial |
| File Type: | Conference Paper |
| Issue: | Volume: S37 Advances in Electromagnetic Modeling by WIPL-D I Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 345 KB |
| Title: | High-Order Nystrom Method for Computing Waveguide Modes |
| Abstract: | We report a novel method for accurately computing the modes of an arbitrarily-shaped hollow waveguide. Our method uses a point-based (Nystrom) discretization of an integral operator over the waveguide aperture to compute the modes. |
| Author(s): | J. J. Ottusch, S. M. Wandzura, J. J. Ottusch, S. M. Wandzura |
| File Type: | Journal Paper |
| Issue: | Volume: 17 Number: 1 Year: 2002 |
| Download Link: | Click here to download PDF File Size: 2246 KB |
| Title: | High-Efficiency and Wideband Bridge Linking Waveguide Waves and Spoof Surface Plasmon Polaritons |
| File Type: | Conference Paper |
| Issue: | Volume: 4-P4-H Properties, Modelling and Novel Concepts of Artificial Electromagnetic Structures Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 274 KB |
| Title: | High Performance Silicon Mach-Zehnder Interferometer Based Photonic Modulator |
| File Type: | Conference Paper |
| Issue: | Volume: S05 Novel Photonic Material and Devices I Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 594 KB |
| Title: | Using Adaptive Cross Approximation for Efficient Calculation of Monostatic Scattering with Multiple Incident Angles |
| Abstract: | An adaptive cross approximation (ACA) based method is proposed for the fast analysis of the monostatic radar cross-section (RCS). Using the low-rank property, several largest eigenvalues and corresponding eigenvectors of the multiple right hand sides can be computed and saved efficiently by the ACA algorithm. The iterative solution of linear equations is required at these principle eigenvectors. Compared with solving linear equations at each angle repeatedly, the proposed method is able to greatly reduce the computation time. In order to efficiently solve the linear equations, the flexible general minimal residual (FGMRES) iterative solver is applied to compute the coefficients of Rao-Wilton-Glisson (RWG) basis functions. Numerical results demonstrate that the proposed method is efficient for monostatic RCS calculation with high accuracy. |
| Author(s): | Z. Liu, R. Chen, J. Chen, Z. Fan |
| File Type: | Journal Paper |
| Issue: | Volume: 26 Number: 4 Year: 2011 |
| Download Link: | Click here to download PDF File Size: 2277 KB |
| Title: | Use of the Simultaneous Diagonalization Technique in the Ax=lBx Eigenproblem Applied to the Computation of the Characteristic Modes |
| Abstract: | Characteristic modes developed by Garbacz, Harrington and Mautz have long been used in the analysis of radiation and scattering from conducting bodies and apertures. For their computation, it is necessary to solve an eigensystem of the form Ax=lBx. If the matrices (A,B) are Hermitian and B is positive definite, the generalized eigenvalue problem can be accurately solved using the simultaneous diagonalization technique (SDT). Because of numerical approximations and rounding sometimes it may happen that the matrices properties deteriorate and the SDT procedure becomes inapplicable. In this work a new technique, developed recently by Higham and Cheng is proposed as a method to solve these deteriorate cases. It is applied to the computation of the characteristic modes for some scattering problems. Results are analyzed and discussed. |
| Author(s): | Giovanni Angiulli, Francesca Venneri, Giovanni Angiulli, Francesca Venneri |
| File Type: | Journal Paper |
| Issue: | Volume: 17 Number: 3 Year: 2002 |
| Download Link: | Click here to download PDF File Size: 152 KB |
| Title: | Uncertainty Quantification and Global Sensitivity Analysis of Radiated Susceptibility in Multiconductor Transmission Lines using Adaptive Sparse Polynomial Chaos Expansions |
| Abstract: | This study analyzes the uncertainties of the radiated susceptibility in multiconductor transmission lines (MTLs), and introduces an adaptive sparse polynomial chaos expansion combining hyperbolic truncation scheme with orthogonal matching pursuit method (AS-PCE (OMP)). This method is used as the basis to realize the uncertainty quantification (UQ) of radiated susceptibility and global sensitivity analysis (GSA) of input variables to output variables. GSA considers the influencing factors of the incident field and transmission-line geometric parameters. The global sensitivity indices of each input variable are calculated for varying impedance loads. The accuracy and efficiency of the proposed method are verified compared with the results of the polynomial chaos expansion based least angle regression method and Monte Carlo methods. |
| Author(s): | Y. Zhu, Y. Wang, Q. Yu, D. Wu, Y. Zhang, T. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 36 Number: 10 Year: 2021 |
| Download Link: | Click here to download PDF File Size: 1113 KB |
| Title: | Uncertainty Analysis on Band-Stop Filter Using Data-Driven Arbitrary Polynomial Chaos |
| File Type: | Conference Paper |
| Issue: | Volume: S17 Uncertainty Quantification in CEM Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 273 KB |
| Title: | Uncertainty Analysis of the EMC Simulation Based on the Non-Intrusive Galerkin Method |
| Abstract: | Recently, as a high-efficient uncertainty analysis method, the Stochastic Galerkin Method has been widely applied in EMC simulations. In this method, the original solver must be changed during uncertainty analysis. Thus, the realization of the Stochastic Galerkin Method may become impossible in some cases. In this paper, a novel method named Non-Intrusive Galerkin method is proposed in order to sove this problem. The performance of the proposed method can be clearly shown by calculating a published example. |
| Author(s): | J. Bai, G. Zhang, L. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 8 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1424 KB |
| Title: | Uncertainty Analysis of Reflection Coefficient for a Coating with Random Flaws Using Adaptive Mesh and DGTD Method |
| Abstract: | An imperfect coating shall cause uncertainties in the analysis of electromagnetic properties. To quantify the influence of irregularity, complexity, and uncertainty of the coatings for electronic devices, an adaptive mesh algorithm combined with the discontinuous Galerkin time domain (AM-DGTD) method is developed. The uncertain variations are incorporated into the proposed algorithm by an appropriate parameterization. The standard statistical analysis is performed to calculate the appropriate moments, i.e., mean and variance. The developed method is validated by modeling a dielectric coating with uncertain flaws in an adaptive mesh grid. The computed quantities of interest from numerical estimations are compared with the analytical values, these results agree with the physical explanation, and are in good agreement with the exact values, as demonstrated by numerical experiments. |
| Author(s): | H. Li, I. Hussain, Y. Wang, Q. Cao |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 5 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2878 KB |
| Title: | Uncertainty Analysis in EMC Simulation Based on Improved Method of Moments |
| Abstract: | Recently, many uncertainty analysis methods have been taken into consideration in electromagnetic compatibility (EMC) simulation. As a traditional method, the Method of Moments (MoM) owns many advantages compared with other methods, especially in calculating the high dimension problems. However, its main disadvantage is the poor accuracy. In this paper, the Richardson extrapolation has been used to improve the MoM in order to promote the accuracy. By using feature selective validation (FSV), the effectiveness of the improvement can be obviously shown compared with the standard results calculated by the Monte Carlo Method (MC). |
| Author(s): | J. Bai, G. Zhang, L. Wang, T. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 1 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 321 KB |
| Title: | Ultra-wideband Miniaturized Electromagnetic Bandgap Structures Embedded in Printed Circuit Boards: Theory, Modeling and Experimental Validation |
| File Type: | Conference Paper |
| Issue: | Volume: Design and Analysis of Advanced Circuit Architectures Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 813 KB |
| Title: | Ultra-Wide Bandwidth Enhancement of Single-Layer Single-Feed Patch Antenna Using the Theory of Characteristic Modes |
| Abstract: | The Theory of Characteristic Modes (TCM) is proposed as a systematic approach to antenna design to achieve the goal of finding the antenna structure with optimum broadband behavior. This theory provides a physical insight to the radiating nature of microstrip patch antennas and reduces the design optimization time. In this work, the resonant behavior of the highly radiating structure of the single U-slot rectangular patch on a single-layer ?r = 4.4 substrate is analyzed using TCM. Modal analysis of this single-layer structure with different single feed excitations concludes that VSWR ? 2 impedance bandwidth in the order of 96% can be achieved with a single T-probe feed. Experimental results, included here, show VSWR ? 2 impedance bandwidth in the order of 71%. |
| Author(s): | M. M. Elsewe, D. Chatterjee |
| File Type: | Express Journal Paper |
| Issue: | Volume: 1 Number: 9 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1411 KB |
| Title: | Ultra-Wide Bandwidth Enhancement of Single-Layer Single-Feed Patch Antenna Using the Theory of Characteristic Modes |
| Abstract: | The Theory of Characteristic Modes (TCM) is proposed as a systematic approach to antenna design to achieve the goal of finding the antenna structure with optimum broadband behavior. This theory provides a physical insight to the radiating nature of microstrip patch antennas and reduces the design optimization time. In this work, the resonant behavior of the highly radiating structure of the single U-slot rectangular patch on a single-layer epsilon r = 4.4 substrate is analyzed using TCM. Modal analysis of this single-layer structure with different single feed excitations concludes that VSWR less than or equal to 2 impedance bandwidth in the order of 96% can be achieved with a single T-probe feed. Experimental results, included here, show VSWR less than or equal to 2 impedance bandwidth in the order of 71%. |
| Author(s): | M. M. Elsewe, D. Chatterjee |
| File Type: | Express Journal Paper |
| Issue: | Volume: 33 Number: 3 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1705 KB |
| Title: | Ultra-Wide Bandwidth Enhancement of Single-Layer Single-Feed Patch Antenna Using the Theory of Characteristic Modes |
| Abstract: | The Theory of Characteristic Modes (TCM) is proposed as a systematic approach to antenna design to achieve the goal of finding the antenna structure with optimum broadband behavior. This theory provides a physical insight to the radiating nature of microstrip patch antennas and reduces the design optimization time. In this work, the resonant behavior of the highly radiating structure of the single U-slot rectangular patch on a single-layer epsilon r = 4.4 substrate is analyzed using TCM. Modal analysis of this single-layer structure with different single feed excitations concludes that VSWR less than or equal to 2 impedance bandwidth in the order of 96% can be achieved with a single T-probe feed. Experimental results, included here, show VSWR less than or equal to 2 impedance bandwidth in the order of 71%. |
| Author(s): | M. M. Elsewe, D. Chatterjee |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 3 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1705 KB |
| Title: | Ultra-Compact Polarization Splitter Based on Silica Liquid Crystal Photonic Crystal Fiber Coupler |
| Abstract: | An ultra-compact polarization splitter based on dual core nematic liquid crystal silica photonic crystal fiber (NLC-PCF) is proposed and analyzed. The refractive index difference between the NLC and silica material guaranties the index guiding through the reported splitter. The dual core NLC-PCF has strong polarization dependence due to the birefringence between the two polarized modes. The coupling characteristics of the proposed design are studied thoroughly using full vectorial fine difference method (FV-FDM) and the propagation analysis is performed by full vectorial finite difference beam propagation method (FVFD-BPM). The numerical results reveal that the reported splitter has short device length of 482 µm with low crosstalk better than -20 dB with wide bandwidths of 31.5 nm and 19 nm for the quasi TE and quasi TM modes, respectively. The compact coupling lengths as well as the low crosstalks over reasonable bandwidths are the main advantages of the reported dual core NLC-PCF. |
| Author(s): | R. A. Hussein, M. F. O. Hameed, S. S. Obayya |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 6 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 594 KB |
| Title: | Ultra Wideband Antenna Analysis |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Electromagnetic Modeling by WIPL-D software II Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 348 KB |
| Title: | Ultra Low profile, Unbalanced Fed Inverted F Antenna on Finite Conducting Plane |
| File Type: | Conference Paper |
| Issue: | Volume: EM Applications using WIPL-D Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 545 KB |
| Title: | Ultra Low Profile Inverted L Antenna on Parallel Wires |
| File Type: | Conference Paper |
| Issue: | Volume: EM Simulations Using WIPL-D Characterization Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 126 KB |
| Title: | UHF-HF RFID Integrated Transponder for Moving Vehicle Identification |
| Abstract: | This paper presents a passive HF-UHF RFID integrated transponder for the identification of a moving vehicle. It consists of a single ISO 7810 ID-1 Card where both a UHF meander dipole antenna and an ISO 15693 commercial tag are arranged. The UHF antenna is designed by using a parametric analysis of the optimal shape of the meanders to obtain a proper conjugate matching between the antenna and the RFID microchip. A single-lane identification scenario is presented and simulated. The effects of the electromagnetic reflection and diffraction on the reading range as well as on the identification operations of a tagged vehicle are also investigated. Numerical simulations and experimental results on a prototype of the conduced transponder confirm the possibility of using this technology for the identification of a moving vehicle approaching a road-toll system with a relatively slow speed. |
| Author(s): | A. Toccafondi, C. D. Giovampaola, P. Braconi, A. Cucini |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 6 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 11189 KB |
| Title: | UHF Flared Notch Antenna Design for Linear Arrays |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Electromagnetic Modeling by WIPL-D software II Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 857 KB |
| Title: | Two-dimensional Full-wave Scattering at One Million Wavelength Objects |
| File Type: | Conference Paper |
| Issue: | Volume: Challenges in Scattering, Radiation and Multi-domain Modeling Number: Year: 2009 |
| Download Link: | Login To Download (For Members) File Size: 672 KB |
| Title: | Two Element UWB-MIMO Antenna with Modified Ground Stub Structure |
| File Type: | Conference Paper |
| Issue: | Volume: S12 Advanced Optimization of Electromagnetic Structures - I Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 431 KB |
| Title: | Two Element Phased Array Dipole Antenna on Finite EBG Ground Plane |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Electromagnetic Modeling by WIPL-D Software Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 171 KB |
| Title: | Two Element Phased Array Dipole Antenna |
| Abstract: | Two element array of dipole antennas with 90 degree phase difference feed is proposed for directional antenna applications. In the numerical analysis, the electromagnetic simulator WIPL-D based on the method of moment is used. At first, the distance between the two elements is fixed to be a quarter wavelengths at the design frequency of 2.45 GHz. The front-to-back ratio is calculated. Then, by adjusting the length of the two elements and the distance between the two elements, a front-to-back ratio of 15.3 dB is obtained. The relation between the front-to-back ratio of this antenna and the feed point currents is discussed. The measured input impedance with 90 degree hybrid |
| Author(s): | Mitsuo Taguchi, Kotaro Era, Kazumasa Tanaka, Mitsuo Taguchi, Kotaro Era, Kazumasa Tanaka |
| File Type: | Journal Paper |
| Issue: | Volume: 22 Number: 1 Year: 2007 |
| Download Link: | Click here to download PDF File Size: 272 KB |
| Title: | Two Element Phased Array Dipole Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Electromagnetic Modeling by WIPL-D Software Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 237 KB |
| Title: | Two Dimensional Frequency-Angle Domain Adaptive Combined Interpolation Method for Electromagnetic Scattering Analysis of Precipitation Particles |
| Abstract: | A combined 2-D interpolation method is proposed for the efficient electromagnetic scattering analysis of precipitation particles over a broad frequency and angular band. This method combines the cubic spline interpolation method and the Steor-Bulirsch model. The cubic spline interpolation method is applied to model the induced current over wide angular band. The Steor-Bulirsch model is applied to accelerate calculation over wide frequency band. In order to efficiently compute electromagnetic scattering, sparsematrix/ canonical grid method (SM/CG) is applied to accelerate the matrix vector multiplication in EFIE. Therefore, the calculation time of frequency and angular sweeps become shorter. Numerical results demonstrate that this combined method is efficient for wide-band scattering calculation of precipitation particles with high accuracy. |
| Author(s): | J. Chen, J. Lin, Z. Liu, N. Li, P. Ping, X. Ping |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 3 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 1720 KB |
| Title: | Tunable Metasurfaces for Filtering the Electromagnetic Waves Under Different Excitations |
| Abstract: | In this study a tunable metasurface has been presented and evaluated for different excitation types. Tunability has been achieved by changing the substrate and geometrical properties. In order to obtain uniqueness, a parameter retrieval for the effective permittivity and permeability is performed using a version of the Nicholson-Ross-Weir (NRW) algorithm that is improved by implementing the Kramers-Kronig relationship. The results regarding the parametric and retrieval analysis are presented. |
| Author(s): | S. Can, E. Karakaya, F. Bagci, A. E. Yilmaz, B. Akaoglu |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 9 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2452 KB |
| Title: | Tucker-FMM-FFT-Accelerated SIE Solver for Large-Scale Electromagnetic Analysis |
| File Type: | Conference Paper |
| Issue: | Volume: S20 The Application of Tensor and Matrix Decompositions to the Electromagnetic Analysis Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 376 KB |
| Title: | Truncation Error Analysis of a Pre-Asymptotic Higher-Order Finite Difference Scheme for Maxwell's Equations |
| Abstract: | Pre-asymptotic higher-order methods are useful to the mitigation of numerical dispersion error in large-scale Finite-Difference Time-Domain (FDTD) simulations. Its truncation error is shown in this study to be 2 2 O O () () :: t s in general. In the limiting case where the CourantFriedrichs-Levy number approaches to zero, it becomes 2 4 O O () () :: t s . |
| Author(s): | Y. Shao, S. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 2 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 164 KB |
| Title: | Transmission plane models for parallel-plane power distribution system and signal integrity analysis |
| File Type: | Conference Paper |
| Issue: | Volume: Applied CEM for EMC Applications Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 120 KB |
| Title: | Transient Response of a Thin Wire above a Real Ground using a Simplified Reflection Coefficient Approach |
| File Type: | Conference Paper |
| Issue: | Volume: Advanced EMC Modeling Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 221 KB |
| Title: | Transient Electro-Thermal Analysis of On-Chip Interconnects in the Presence of ESD Pulses Using DGTD Method |
| File Type: | Conference Paper |
| Issue: | Volume: 10-TE-1 Electromagnetic Environment Effects and Protection II Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 295 KB |
| Title: | Transient Electro-Thermal Analysis of a Common Source Amplifier Circuit with a Physics-based MOSFET Model |
| Abstract: | An algorithm that combines a common source amplifier with the physics-based metal-oxidesemiconductor field effect transistor (MOSFET) model is proposed. By solving the coupled drift-diffusion model equations with spectral element time-domain (SETD) method, the distribution of electron quasi-Fermi potential, hole quasi-Fermi potential and the potential inside the MOSFET is obtained. The corresponding current densities and electric intensities distributed in the device can be used to couple the heat conduction equation. Furthermore, the Kirchhoff laws should be satisfied when the MOSFET device is inserted in the circuit. The Newton-Raphson method is used to solve the nonlinear circuit equations due to the existence of semiconductor devices. The transient electro-thermal characteristics of a common source amplifier circuit have been analyzed, and the numerical results demonstrate the validity of the proposed method. |
| Author(s): | T. Pan, D. Ding, H. Li, X. Cheng |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1348 KB |
| Title: | Transient Current Distribution and Force Analysis of Three Phase Enclosure Type GIB Based on Field-Circuit Coupling FEM Method |
| Abstract: | On the purpose of optimal design and online monitoring of three phase enclosure gas insulated bus (GIB), a 3-D circuit-field coupling FEM model has been developed. The current constriction effects in plug-in connectors are simulated by modeling contact bridges between contact surfaces and the influence of conductor gravity on contact resistance has been taken into account. The distributions of current which is constrained by external circuit are obtained from fieldcircuit coupling calculation and electromagnetic force, which is derived from electromagnetic field calculation, is used as load inputs in mechanical field analysis. The validity of calculation model is demonstrated by comparing with vibration experiments. The dynamic current distribution and electromagnetic force behaviors of three phase enclosure GIB under steady state and different short circuit conditions have been analyzed using the calculation model. Analysis results show that the uneven heating of contact fingers due to current distributions under steady state and contact fingers with smaller contact forces are seriously ablated by large short currents under short circuit conditions, and are the main contact degradation mechanism of plug-in connector. Conductor electromagnetic forces under single phase short circuit condition are larger than those of two phase and three phase short circuit conditions and the electromagnetic force peak moments under different fault conditions are not the same. |
| Author(s): | X. Guan, B. Kang, N. Shu, Q. Yan, Z. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 30 Number: 11 Year: 2015 |
| Download Link: | Click here to download PDF File Size: 1194 KB |
| Title: | Transient Analysis of Thin-Wire Antennas over Debye Media |
| Abstract: | This paper presents a numerical procedure to calculate the time-domain response of thin-wire antennas over Debye media. The method is based in an expansion of the electricfield integral-equation in the time-domain (EFIETD), which accounts for the Debye media by using a reflection-coefficient approach. Resulting extended integral equation is subsequently solved by the method of moments. Numerical examples including Debye soils show not only the accuracy of the method but also a higher computational efficiency in comparison with other hybrid numerical techniques. |
| Author(s): | M. F. Pantoja, A. R. Bretones, S. G. García, X. L. Travassos, R. G. Martín |
| File Type: | Journal Paper |
| Issue: | Volume: 27 Number: 3 Year: 2012 |
| Download Link: | Click here to download PDF File Size: 1010 KB |
| Title: | Transient Analysis of Dispersion Medium with Conducting Strips buried in Different Depth |
| File Type: | Conference Paper |
| Issue: | Volume: S46 Time-Domain Techniques for Designing Electromagnetic and Optical Devices - II Number: Year: 2021 |
| Download Link: | Login To Download (For Members) File Size: 208 KB |
| Title: | Transient Analyses of Grounding Electrodes Considering Ionization and Dispersion Aspects of Soils Simultaneously: An Improved Multiconductor Transmission Line Model (Improved MTL) |
| Abstract: | This paper proposes an approximate model in the frequency domain for transient analysis of grounding electrodes buried in ionized and dispersive soils. The proposed method, called multi-conductor transmission line model (MTL), can easily treat the frequency dependence of electrical parameters of soil. It can also incorporate soil ionization by gradually changing the respective electrode radius. Extensive simulation results are presented to confirm the accuracy of the MTL. |
| Author(s): | S. S. Sajjadi, V. Aghajani, S. R. Ostadzadeh |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 5 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1223 KB |
| Title: | Transient Adjoint Sensitivities for Problems with Multiple Discontinuities exhibiting Space Dependent Properties |
| File Type: | Conference Paper |
| Issue: | Volume: Efficient Solutions to Inverse Electromagnetic Problems Number: Year: 2010 |
| Download Link: | Login To Download (For Members) File Size: 646 KB |
| Title: | Towards Wideband Hyperthermia Treatment System |
| Abstract: | This paper presents an overview of design and functionality of the essential modules proposed to build a wideband hyperthermia system. Description is provided of the waveform shaper, power amplifier and applicator array modules. Big data analysis is presented to accelerate energy localization depending on a time reversal technique. Simulation results are provided assuming a cylindrical head phantom characterized with wideband dispersive tissue properties, and the obtained field maps are shown in different planes to visualize energy localization process. Results reveal that wideband operation has the potential to enhance energy localization in deep tumor regions while eradicating hot spots, as compared to conventional narrowband systems. |
| Author(s): | N. Nizam-Uddin, W. Alkadri, W. A. Malik, I. Elshafiey, A. F. Sheta |
| File Type: | Journal Paper |
| Issue: | Volume: 32 Number: 9 Year: 2017 |
| Download Link: | Click here to download PDF File Size: 2587 KB |
| Title: | Tolerance Analysis and Robust Design in Engineering Electromagnetics – An Interval Analysis Perspective Abstract |
| File Type: | Tutorial Abstract |
| Issue: | Volume: S56 Tolerance Analysis and Robust Design in Engineering EM Number: Year: 2017 |
| Download Link: | Login To Download (For Members) File Size: 457 KB |
| Title: | TM scattering from nite rectangular grooves in a conducting plane using overlapping Tblock analysis |
| File Type: | Conference Paper |
| Issue: | Volume: Fast and Efficient CEM Methods Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 189 KB |
| Title: | Time-Domain Spectral Inversion Method for Characterization of Subsurface Layers in Ground-Penetrating-Radar (GPR) Applications |
| Abstract: | Ground-Penetrating-Radar (GPR) data analysis has been widely utilized in subsurface and geophysics applications. One of the applications turning into great importance is multilayer subsurface hydraulic parameter identification and soil water content estimations. The classic GPR techniques have shown limitations in detecting deeper soil layers and unsatisfactory accuracy in estimating the electrical properties of the layers. Spectral inversion methods have been recently identified and developed to be an effective tool to tackle these problems. In this work, the spectral inversion method is extended in time-domain and a comprehensive formulation of the algorithm along with an improved well-defined cost function is presented. The Time-Domain Spectral Inversion (TDSI) method is then applied to environmentally-relevant multilayer soil geometries and the corresponding estimated electrical properties are drawn. The results show the TDSI method considerably ameliorates the performance of the inversion in terms of simplicity, accuracy, and applicability. |
| Author(s): | Z. Motevalli, B. Zakeri |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 1 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2142 KB |
| Title: | Time-Domain Response of 3-D Structures Calculated Using WIPL-D |
| File Type: | Conference Paper |
| Issue: | Volume: Advances in Electromagnetic Modeling by WIPL-D Software Number: Year: 2007 |
| Download Link: | Login To Download (For Members) File Size: 647 KB |
| Title: | Time Response Analysis of Cable over Anisotropic Half Space |
| File Type: | Conference Paper |
| Issue: | Volume: 9-P-2 Poster Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 272 KB |
| Title: | Time of Flight Extraction of Dispersive Lamb Wave by Ridge Analysis |
| File Type: | Conference Paper |
| Issue: | Volume: 5-P-1 Poster Number: Year: 2018 |
| Download Link: | Login To Download (For Members) File Size: 263 KB |
| Title: | Time Domain Parabolic Equation Method for Scattering Analysis of Electrically Large Coated Objects by using Impedance Boundary Condition |
| Abstract: | The time domain parabolic equation method (TDPE) is an efficient tool for analyzing electromagnetic (EM) scattering by electrically large objects. It reduces the cost of computational resources by dividing threedimensional solution space into multiple twodimensional transverse planes for calculating scattered fields one by one. For thin coated perfectly electrically conducting (PEC) objects, the efficiency of TDPE method will decrease if dielectric is considered to be meshed. As an approximate method, Leontovich impedance boundary condition (IBC) handles this problem by modeling a surface impedance on the outer surface of coating dielectric, instead of solving Maxwell's equations in the dielectric domain. Thus in this paper, TDPE method based on Leontovich IBC is proposed to analyze broadband scattering problems of large-scale coated PEC objects. Numerical results have validated the accuracy and efficiency of the proposed method. |
| Author(s): | L. Guan, S. Tao |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 12 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1612 KB |
| Title: | Time Domain Analysis of Ultra-Wide Band Signals from Buried Objects Under Flat and Slightly Rough Surfaces |
| Abstract: | The analysis of transient scattering for TMz (horizontally) polarization from a cylindrical perfectly conducting (PEC) object buried in a lossy medium is considered. Flat and slightly surface cases are considered for the dielectric halfspace. Our previous work using a decomposition method solution in frequency domain of TMz polarization is utilized to solve this scattering problem. Then, an inverse Fourier transform is used to get the time domain signals. Timing analysis is done by calculating the travelling time of reflected signals in the possible paths. Then, multiple reflections are identified using these travelling times. Finally, the results from the flat and slightly rough surface profiles are used to compare the effects of multipath propagation. |
| Author(s): | S. MakalYucedag, A. Kizilay |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 519 KB |
| Title: | Time Domain Analysis of GaAS MESFET Transistors Excited by an Incident Electromagnetic Field |
| Abstract: | A numerical method for the fully distributed modeling of Field Effect Transistor (FET) excited by an incident electromagnetic field using a Finite-Difference Time-Domain (FDTD) method is described. The transistor is modeled using the fully distributed model which consists of a configuration of the conventional equivalent circuit of the transistor and three coupled lines as each distributed element. The distributed source terms represent the coupling with an electromagnetic field in the equation which can be used in the Electromagnetic Interference (EMI) analysis. As a numerical example, the method is applied to a GaAs MESFET and the time domain results are presented. |
| Author(s): | L. Mirzavand, A. Abdipour, R. Mirzavand |
| File Type: | Journal Paper |
| Issue: | Volume: 29 Number: 10 Year: 2014 |
| Download Link: | Click here to download PDF File Size: 637 KB |
| Title: | Time Domain Analysis of a Microstrip Line Excited Compact Rectangular Dielectric Resonator Antenna |
| File Type: | Conference Paper |
| Issue: | Volume: FDTD and Applications Number: Year: 2004 |
| Download Link: | Login To Download (For Members) File Size: 76 KB |
| Title: | Time and Frequency Evolution of Precursor Fields in Dispersive Media using FDTD and Joint Time-Frequency Analysis |
| File Type: | Conference Paper |
| Issue: | Volume: Electromagnetic Analysis of Wave Phenomena Number: Year: 2005 |
| Download Link: | Login To Download (For Members) File Size: 225 KB |
| Title: | Three-Dimensional Electromechanical Coupled Analysis for Capacitive RF MEMS Switches |
| File Type: | Conference Paper |
| Issue: | Volume: Novel Modeling Techniques and RF MEMS Number: Year: 2006 |
| Download Link: | Login To Download (For Members) File Size: 831 KB |
| Title: | Three-Dimension Finite Element Analysis of a Helical Motion Induction Motor |
| Abstract: | The paper presents a three-dimensional finite element analysis applicable to all forms of sheet rotor, cylindrical, linear induction motor, as well as, helical motion induction motor. The analysis accounts for longitudinal and transverse end effects, skin depth and finite sheet thickness; furthermore, there is practically no restriction on the shape of magnetic circuit that can be considered. It yields detailed space profile of the state variables. The winding arrangement may include multi-polar system circumferentially and axially. The excitation produced by such winding is a helically traveling wave. The formulation results in a set of linear equations which are solved by point relaxation method. The solution algorithm employs power mismatch in the machine to indicate accuracy. The theory is supported by experimental results. |
| Author(s): | J. H. Alwash, L. J. Qaseer |
| File Type: | Journal Paper |
| Issue: | Volume: 25 Number: 8 Year: 2010 |
| Download Link: | Click here to download PDF File Size: 352 KB |
| Title: | THREE METHODS FOR EVALUATION OF FREQUENCY-DEPENDENT RESISTANCES AND INDUCTANCES OF MULTICONDUCTOR TRANSMISSION LINES |
| Abstract: | Three methods for the analysis of frequency-dependent resistances and inductances of multiconductor transmission lines are outlined and compared. The first method comes from power-engineering applications, and it is based on a numerical solution of an integral equation for the distribution of the conductor volume currents. The second method is based on the perturbation technique. The third method comes from high-frequency applications, and it is based on the principle of equivalent surface electric and magnetic currents. [Vol. 9, No. 2 (1994), Special Issue on The Numerical Computation of Low Frequency Electromagnetic Fields, pp 43-56] |
| Author(s): | Antonije R. Djordjevic, Tapan K. Sarkar, Antonije R. Djordjevic, Tapan K. Sarkar |
| File Type: | Journal Paper |
| Issue: | Volume: 9 Number: 2 Year: 1994 |
| Download Link: | Click here to download PDF File Size: 797 KB |
| Title: | Three Dimensional Finite Element Analysis for the Study of Voltage Drop Behavior in Zinc Air Batteries under Load Conditions |
| File Type: | Conference Paper |
| Issue: | Volume: S20 Advanced Computational Techniques in Electromagnetics Number: Year: 2015 |
| Download Link: | Login To Download (For Members) File Size: 289 KB |
| Title: | Thin Wire Representation of the Vertical Conductor in Surge Simulation |
| Abstract: | Abstract— Simulation of very fast surge phenomena in a three-dimensional (3-D) structure requires a method based on Maxwell’s equations, such as the FDTD (finite difference time domain) method or the MoM (method of moments), because circuit-equation-based methods cannot handle the phenomena. This paper describes a method of thin wire representation of the vertical conductor system for the FDTD method which is suitable for the 3-D surge simulation. The thin wire representation is indispensable to simulate electromagnetic surges on wires or steel frames of which the radius is smaller than a discretized space step used in the FDTD simulation. A general surge analysis program named VSTL (Virtual Surge Test Lab.) based on the Maxwell equations formulated by the FDTD method is used to simulate the surge phenomena of a vertical conductor, including the effects of ground plane and without ground plane. By use of the Maxwell equations, VSTL is inherently able to take into account the three-dimensional geometrical features of a simulated structure unlike EMTP-type circuit-based transient programs. Comparisons between calculated results by the FDTD method, theoretical results and computed results by the NEC-2 (Numerical Electromagnetic Code) based on the MoM are presented to show the accuracy of the thin wire representation. |
| Author(s): | Md. Osman Goni, Eiji Kaneko, Hideomi Takahashi, Md. Osman Goni, Eiji Kaneko, Hideomi Takahashi |
| File Type: | Journal Paper |
| Issue: | Volume: 19 Number: 1 Year: 2004 |
| Download Link: | Click here to download PDF File Size: 322 KB |
| Title: | Thermal-Aware DC IR-Drop Co-Analysis of 3-D ICs using Non-Conformal Domain Decomposition Methods |
| File Type: | Conference Paper |
| Issue: | Volume: Multi-Physics Modeling and Simulations Number: Year: 2012 |
| Download Link: | Login To Download (For Members) File Size: 241 KB |
| Title: | Thermal Simulation of a Conductive Fabric Sheet Subjected to a Lightning-like Current |
| File Type: | Conference Paper |
| Issue: | Volume: S14 Numerical Methods for Diverse Applications Number: Year: 2020 |
| Download Link: | Login To Download (For Members) File Size: 432 KB |
| Title: | Thermal Simulation of a Conductive Fabric Sheet Subjected to a Lightning-like Current |
| Abstract: | A sample of electroconductive fabric subjected to a lightning-like current impulse is analyzed in this contribution. A multiphysics simulation is used to calculate the temperature distribution produced by a lightning-like current flowing through the material sample. A decoupled, electromagnetic (EM) and thermal, simulation was conducted for the analysis and is explained in the paper. The scaling factor calculation to represent the energy presented during current impulse tests is |