ACES Publication Search





There are 53 search results for:



Title: ACES Journal February 2019 Cover
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 2166 KB

Title: ACES Journal February 2019 Front/Back Matter
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 822 KB

Title: ACES Journal February 2019 Full
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 42823 KB

Title: Surface Integral Computation for the Higher Order Surface Integral Equation Method of Moments
Abstract: This paper presents extraction technique applied to the double higher order surface integral equation method of moments and discusses the numerical results compared with previously implemented extraction method and numerical Gauss-Legendre integration.
Author(s): S. B. Manic, B. M. Notaros
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1470 KB

Title: Millimeter-wave Frequency FDTD Simulation for Error Vector Magnitude of Modulated Signals
Abstract: At millimeter frequencies, a simulation of propagating complex modulated signals through an environmental channel can be computationally prohibitive using the finite difference time domain method. A transfer function approach known as the “grid impulse response” method uses a deltafunction as a source signal to solve for the transfer function of the finite difference time domain grid. Once the transfer function of the channel is known, any number of source signals of differing lengths, such as those involving M-ary quadrature amplitude modulation may be used to estimate the propagation of a complex modulated signal through the environmental channel. Numerical investigations show that the maximum error between the two approaches can be very small. Simple environmental channels are used to present the error vector magnitude at mmWave frequencies obtained from the grid impulse response method.
Author(s): J. E. Diener, J. Quimby, K. A. Remley, A. Z. Elsherbeni
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1464 KB

Title: Hierarchical Universal Matrices for Sensitivity Analysis by Curvilinear Finite Elements
Abstract: A new method for calculating the geometric sensitivities of curvilinear finite elements is presented. Approximating the relevant metric tensors by hierarchical orthogonal polynomials enables the sensitivity matrices to be integrated analytically. The resulting numerical method is based on pre-calculated universal matrices and achieves significant savings in computer runtime over conventional techniques based on numerical integration. Moreover, there exists a representation limit for the geometry, i.e., the degree of basis functions fully determines a critical order of the geometry expansion, beyond which the derivatives of the finite-element matrices will remain constant. To validate the suggested approach, a numerical example is presented.
Author(s): L. L. Toth, R. Dyczij-Edlinger
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1160 KB

Title: A DC to HF Volume PEEC Formulation Based on Hertz Potentials and the Cell Method
Abstract: A new Partial Element Equivalent Circuit formulation based on Hertz potentials and the Cell Method is presented. Conductive, dielectric, and magnetic linear-homogeneous media are considered by means of conduction, polarization, and magnetization current densities. The use of edge unknowns leads to reduce system size with respect to typical face-based approaches.
Author(s): R. Torchio, P. Alotto, P. Bettini, D. Voltolina, F. Moro
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1359 KB

Title: Adjoint Methods for Uncertainty Quantification in Applied Computational Electromagnetics: FEM Scattering Examples
Abstract: We present methods for quantifying uncertainty and discretization error of numerical electromagnetics solvers based on adjoint operators and duality. We briefly introduce the concept of the adjoint operator and describe applications of adjoint solutions for predicting and analyzing numerical error and approximating sensitivity of a given quantity of interest to a given parameter. Forward solutions are based on the higher order finite element method (FEM).
Author(s): C. L. Key, A. P. Smull, D. J. Estep, T. D. Butler, B. M. Notaros
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1626 KB

Title: Impact of Flat Radomes on Amplitude-Only Direction Finding Performance
Abstract: We investigate the impact of placing a thin flat radome in front of an amplitude-only direction finding (AODF) antenna system. The considered system consists of two identical Ka-band, air-filled horn antennas squinted off boresight by 30degrees for direction finding (DF) error within ±0.82degrees/dB over a field-of-view (FoV) from -20degrees to +20degrees. Computational results with various radome materials, thicknesses, and placements indicate that it is possible to maintain excellent DF performance if radome is properly designed and located.
Author(s): M. A. Al-Tarifi, D. S. Filipovic
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1585 KB

Title: Efficient Multiphysics and Multiscale FDTD Methods for Terahertz Plasmonic Devices
Abstract: Modeling terahertz plasmonic devices is a multiphysics and multiscale problem. Due to high mesh density in the electron transport regions, the simulation times are long. In this work, we develop hybrid coupled finite difference time domain (FDTD) methods for fast design of terahertz plasmonic devices. The methods employ implicit solution (using Alternate Direction Implicit), coupled with hydrodynamic modeling for plasmonic applications. The theory, simulation and timeimprovement related results will be presented at the conference.
Author(s): S. Bhardwaj
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1448 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: 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: Micromagnetic Model Simulation of Spin-Torque Oscillator and Write Head for Microwave-Assisted Magnetic Recording – Spin Injection Layer with In-Plane Anisotropy –
Abstract: Micromagnetic simulations were carried out to obtain stable oscillation of a spin transfer torque oscillator (STO) inserted into the gap between the main pole and trailing shield of a write head. We assumed a spin injection layer with in-plane anisotropy. Results show that reducing the magnetostatic interaction between the write head and the STO is the key to obtaining stable STO oscillation.
Author(s): Y. Kanai, R. Itagaki, S. Greaves, H. Muraoka
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1273 KB

Title: Nano-Optical Couplers for Efficient Power Transmission Along Sharply Bended Nanowires
Abstract: We consider nano-optical couplers that consist of optimal arrangements of nanoparticles to improve the transmission abilities of nanowire systems with sharp bends. Previously, it was shown that absence/existence of nanoparticles in a given grid can be optimized such that the power transmission can significantly be increased without curving the bend. In this contribution, we present a detailed investigation and analysis of coupler performances to critical geometric parameters. While the designed couplers are robust against fabrication errors, numerical results demonstrate a remarkable dependency of coupler characteristics to particle types, as well as to bending geometry, due to strong plasmonic interactions at short distances. These findings further support the need for case-dependent optimization that must be performed efficiently and accurately via full-wave simulations.
Author(s): A. Altinoklu, O. Ergul
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 2433 KB

Title: 3D Diagonalization and Supplementation of Maxwell’s Equations in Fully Bi-anisotropic and Inhomogeneous Media - Part I: Proof of Existence by Construction
Abstract: Consider the Maxwell’s curl equations in fully bi-anisotropic and inhomogeneous media in three dimensional (x, y, z) spatial Cartesian coordinates. Let the media be characterized by 3 × 3 permittivity, electro-magnetic coupling, magneto-electric coupling, and permeability matrices epsilon3x3(x, y, z), xi 3x3(x, y, z), zeta3×3(x, y, z), and mu3×3(x, y, z), respectively. Assume a harmonic time-dependence according to exp(–jwt). The prime objective in this paper is to establish that the Maxwell’s electrodynamic equations jointly with the constitutive equations can be diagonalized, leading to the D–, and the associated supplementary S–forms. A finitary algorithm involving ‘‘structural,’’ ‘‘differential,’’ and ‘‘material’’ matrices has been proposed, and the existence of the D– and S–forms proved by construction. In the accompanying paper (Part II) the internal consistency of the D– and S–forms has been shown, by proving their sharp equivalence with Maxwell’s and constitutive equations.
Author(s): A. R. Baghai-Wadji
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1043 KB

Title: 3D Diagonalization and Supplementation of Maxwell’s Equations in Fully Bi-anisotropic and Inhomogeneous Media - Part II: Relative Proof of Consistency
Abstract: Consider fully bi-anisotropic and inhomogeneous media supporting the electromagnetic wave propagation. Assume an (x, y, z)–Cartesian coordinate system and a harmonic time-dependence according to exp(–jwt). In the accompanying paper (Part I) it was shown that the Maxwell’s equations can be diagonalized with respect to the z–axis, resulting in the Dc–form. Furthermore, the existence of the associated supplementary matrix equation, the Sc–form, was demonstrated rigorously. In the present paper ‘‘structural,’’ ‘‘differential,’’ and ‘‘material’’ matrices have been introduced to explicate the (Da, Sa)–, (Db, Sb)–, and (Dc, Sc)–forms, relative to the x–, y–, and z–axes, respectively. As the pinnacle of the theory, it has thoroughly been established that the derived combined (Dc, Sc)–forms are sharply equivalent with the joint Maxwell’s and constitutive equations, and thus internally consistent. The presented proof is relative in the sense that its validity hinges on the consistency of Maxwell’s equations and the material realizability conditions.
Author(s): A. R. Baghai-Wadji
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1031 KB

Title: 3D Diagonalization and Supplementation of Electrostatic Field Equations in Fully Anisotropic and Inhomogeneous Media Proof of Existence and Consistency
Abstract: Consider Maxwell’s homogeneous curl equation divergence × E = 0 for the electric field vector E and the inhomogeneous divergence equation divergence · D = rho for the dielectric displacement vector D and the charge density function rho in the static limit. Assume an (x, y, z)–Cartesian coordinate system. Consider the constitutive equation D = epsilon E, with the 3 × 3 position-dependent positive-definite permittivity matrix epsilon (x, y, z) modeling fully anisotropic and inhomogeneous dielectric media. This paper proves that divergence × E = 0 and divergence · D = rho along with D = epsilon E are diagonalizable with respect to the arbitrarily chosen z–axis leading to the Dc–form. The existence of an associated supplementary equation, the Sc–form, has also been demonstrated. Finally, it is shown that the constructed (Dc, Sc)–forms are sharply equivalent with the originating set of equations divergence × E = 0, divergence · D = rho, and D = epsilon E, and, thus, internally consistent. The proof scheme is relative in the sense that its validity hinges on the consistency of Maxwell’s equations in the static limit and the material realizability conditions.
Author(s): A. R. Baghai-Wadji
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1033 KB

Title: Mode Tracking for Parametrized Eigenvalue Problems in Computational Electromagnetics
Abstract: An algorithm to perform a mode tracking for parameter dependent eigenvalue problems in computational electromagnetics is presented. It is based on a Taylor expansion using the derivatives of the eigenvalue and the eigenvector and allows distinguishing between intersection and touching points in the eigenvalue curves. The method is applied to discretizations with both the finite integration technique (FIT) and the finite element method (FEM), leading to simple and generalized eigenvalue problems, respectively. The applications include the calculation of the Brillouin diagram for a periodic structure and the variation of a material parameter in a filter structure.
Author(s): P. Jorkowski, R. Schuhmann
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1263 KB

Title: Parametric Models for Signature Prediction and Feature Extraction
Abstract: This paper compares and contrasts numerical electromagnetic (EM) prediction methods and parametric scattering models for radar signature prediction and feature extraction.
Author(s): J. A. Jackson
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1281 KB

Title: A Dual Band-Reject FSS for WI-FI Application
Abstract: A dual band FSS based on array of double square ring shaped resonators has been proposed. The proposed structure represents a wide-angle perfect the WI-FI signals and screen room applications. Simulation results show polarization independency for both rejection bands.
Author(s): M. Bahadorzadeh, C. F. Bunting
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1308 KB

Title: Mathematical Relationship of an Isotropic Point Source and the Spherically Distributed Antenna Array
Abstract: This work investigates beam pattern behavior of an isotropic point source and a collection of sources distributed amongst a spherical volume. Pattern behavior is compared to the tapering of a plane wave expansion of spherical waves demonstrating self-adjoint characteristics. Beampatterns of atomic like orbitals and Zernike polynomials are provided as connections to common applications.
Author(s): K. Buchanan, T. Adeyemi, C. Flores-Molina, S. Wheeland, S. Weiss
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 2064 KB

Title: Multiband Antenna for Wireless Applications Including GSM/UMTS/LTE and 5G Bands
Abstract: A simple ultra thin multiband antenna is introduced. The proposed antenna with four bands covers many wireless applications. The proposed antenna has simple configuration including two open L-shaped slots to create resonat mode at GSM and GPS bands and also two rectangular slots on the radiating element for creating multi resonant modes to meet the specifications of mentioned frequency bands. According to the simple, small and planar configuration, the proposed antenna design is inexpensive and can easily be integrated with the other microwave circuit boards. The proposed antenna has the small size of 10 mm and the total size of 120 mm x 60 mm x 0.5 mm, promising to be used widely in compact and ultra slim handsets.
Author(s): A. J. Khalilabadi, A. Zadehgol
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1115 KB

Title: Enhancement of Parameters of Slotted Waveguide Antennas Using Metamaterials
Abstract: An approach to increasing the gain of a slotarray antenna through the use of metamaterials is presented. The specific array antenna used in this study is a 2x4 resonant, slotted-waveguide array, although the results presented should be applicable to most arrays with slot radiators. To achieve increased gain, a metamaterial structure comprised of a split-ring resonator in conjunction with a wire structure was placed above the radiating slots. Modeled results for this configuration predicted an increase in directivity of 49%, and this result was subsequently validated by fabricating and performing measurements on antenna arrays incorporating the metamaterials. The increase in directivity also resulted in increased efficiency and sidelobe depth and yet did not degrade return loss. The measured results show that the maximum gain enhancement of antennas with metamaterials increased by up to 58% with respect to the control antenna which did not employ metamaterials.
Author(s): M. Valayil, K. Chamberlin
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1648 KB

Title: A Novel Design of Non-Uniform Reflectarrays with Symbolic Regression and its Realization using 3-D Printer
Abstract: Herein, a novel design of an X-band Non- Uniform Reflectarray Antenna (NURA) with Symbolic Regression SR and its fabrication using 3D Printer technology are presented. A NURA is consist of simply a grounded dielectric layer with the variable thickness. Firstly, SR is employed to obtain with a great accuracy for the reflection phase characteristics of a grounded dielectric layer in the analytical form within the continuous domain of 1 less than or equal to epsilon r less than or equal to 6 and thickness 0.1 less than or equal to h less than or equal to 3 mm for the X-band. For this purpose, SR is trained and validated by the 3D CST Microwave Studio data. Then, for the design purpose of NURA, a special fine reflection calibration characteristic is built up again by SR with the sufficient reflection phase range of the 3D Printer’s material at the operation frequency 10 GHz. In the third step, the designed NURA is then prototyped by using 3D printer technology where the material can be easily shaped and create unit cell at printing accuracy of 0.1 mm per layer. Thus, by this mean the prototyping cost of non-uniform Reflectarray design can be reduced drastically both in means of time and ease of manufacturing. In the final step, mismatching and radiation properties of the prototyped NURA are measured.
Author(s): P. Mahouti, F. Gunes, M. A. Belen, A. Caliskan
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1936 KB

Title: Asymmetric Band Structure Calculations Using the Plane Wave Expansion Method with Time-Modulated Permittivity
Abstract: In this work we show how the plane wave expansion method for calculating the band structure of materials with periodic electric permittivity may be extended to calculate the band structure of periodic materials that also possess a sinusoidal time-modulation. The numerical technique is applied to a structure possessing a synthetic linear momentum which causes unidirectional bandgaps to appear in the band structure. Such devices could be of use for tunable magnet-free isolators in integrated photonics platforms.
Author(s): A. Mock
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1153 KB

Title: Patch Antenna Size-Reduction Parametric Study
Abstract: Size-reduction techniques are applied to a circular UHF patch antenna, by varying parameters to better predict its desired resonant frequency. Specifically, slits are introduced into the patch, which are parametrically varied to determine the optimum slit dimensions for maximum size reduction. Further studies determine the optimum location for the probe feed, to achieve 50omega input impedance for different slit lengths.
Author(s): R. L. Musselman, J. L. Vedral
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1672 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: Patch Antenna with Multiple Slits and Circular Shaped
Abstract: In this paper, a circular shaped ground-fed patch antenna is designed, simulated, built and tested. The operating antenna frequency is 14.6 GHz with -15.68 dB input and 8.14 dB gain. Furthermore, the antenna have multiple slits in a circular main body, and also supported with triangle and rectangle shapes. The measurements of the fabricated patch antenna matches the simulation results.
Author(s): F. Atalah, M. Imeci, O. Gungor, 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: 1570 KB

Title: Probe Feed E-Shaped Patch Antenna at 4.87 GHz
Abstract: In this paper, E-shape microstrip patch antenna for wireless communication is designed, simulated, built and tested. The operating frequencies of antenna are 2.97 GHz and 4.85 GHz, the substrate FR4 is used for proposed antenna with dielectric constant 4.01 and 1.7mm thickness. Two parallel slots are cut to perturb the surface current path to achieve dual resonance. The E-shape has return loss of -28 dB and -14.03 dB at operating frequencies 2.97 GHz and 4.85 GHz respectively. Designing and simulation of this antenna has been done by the help of Sonnet Software. This antenna is fed by a co-axial probe feeding. In this paper, the effects of length difference among antenna legs has been studied.
Author(s): E. Kucuk, B. Bayram, 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: 1371 KB

Title: Multiple Rectangular Slotted Patch Antenna with Roof-top Shaped at 15.3 GHz
Abstract: In this paper, a compact sized, high frequency microstrip patch antenna with probe feeding is designed, simulated, built and tested. The patch of the antenna is diamond shaped which has a rectangular slot in the upper-center. Main contribution of the paper is to perturb the side edges of the patch and to add a rectangular slot. Parametric study of that twosubstrate change was investigated. The proposed structures were simulated by using the Sonnet Suites, a planar 3-D electromagnetic simulation software which gave S11 value of -13.82 dB and gain value of 6.33 dB at 15.3 GHz.
Author(s): M. E. Koca, T. Durak, S. T. Imeci
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1450 KB

Title: Optimizing Scattering Coefficients of Disordered Metamaterials Using the Finite-Difference Time-Domain Method
Abstract: A technique based on the finite-difference timedomain method is presented for calculating optical transmission and reflection of disordered nanoparticle stacks. The approach is used to optimize a nanoparticle stack exhibiting greater than 98% average absorption over the visible spectrum.
Author(s): A. Mock, S. Hewlett
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1612 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: 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: Efficient Modeling of Antennas with Finite Conductivity using Calderon Preconditioning
Abstract: A Calderon preconditioner for a novel single-source integral equation, which allows the simulation of high dielectric contrasts and lossy conductors, is introduced. It is shown that this preconditioner avoids breakdown when simulating scattering problems including high permittivities. This is corroborated by a numerical example of a receiving copper dipole antenna.
Author(s): M. Gossye, D. Vande Ginste, D. De Zutter, H. Rogier
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1127 KB

Title: Directional of Arrival Tag Response for Reverse RFID Localization
Abstract: A positioning system implemented with RFID technology is explored for a GPS-denied environment such as an underground mine or tunnel. A new method of two-dimensional localization is developed based on the angles of arrival of three tag’s responses that are located at known positions. This method reduces the error when the localization process is based on the received signal strength from an RFID tag signal. Passive tags are placed in predefined locations with known information about their coordinates. An RFID reader attached to a robot with a directive antenna is used to get the AOA of the signals received from the tags. The AOA information is then used for triangulating the position of a reader’s location (reverse localization).
Author(s): A. D. Zarrini, A. Elsherbeni, J. F. Brune
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1289 KB

Title: EIT Images of Human Inspiration and Expiration using a D-bar Method with Spatial Priors
Abstract: The inclusion of a spatial prior in the high-frequency regime of the scattering transform for the 2-D D-bar method for electrical impedance tomography is studied for use with human subject data. The effects and balance of the two regularization parameters for the inverse problem are studied. Results on data from human volunteers reveal improved spatial resolution when compared to inspiratory and expiratory CT scans.
Author(s): M. Alsaker, J. L. Mueller
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 4763 KB

Title: Domain Decomposition Method for Scattering from an Aircraft with Jet Engine Inlet Cavity
Abstract: Monostatic radar cross section (RCS) of an combat aircraft is analyzed using iterative Least Square Method weighted domain decomposition method (LSM weighted DDM). The model of the 200 wavelengths long aircraft is made of perfect electric conductor (PEC). Inlet cavity of the jet engine is included in the model. The inlet has realistic shape, whereas cavity is closed with a PEC on the outlet side. Corresponding model without the inlet is also analyzed—the inlet contour is smoothed, and then it is closed with a PEC. Method of moments (MoM) solution is used as a reference. It is shown that the LSM weighted DDM solution can provide very good solution in just a few iterations if problematic parts of the structure are extracted in separate subdomains.
Author(s): M. S. Tasic, B. M. Kolundzija, T. S. Milosevic
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 2557 KB

Title: Modeling and Validation of a mm-Wave Shaped Dielectric Lens Antenna
Abstract: The modeling and validation of a 33 GHz shaped dielectric antenna design is investigated. The electromagnetic modeling was performed in both WIPL-D and FEKO, and was used to validate the antenna design prior to fabrication of the lens. It is shown that both WIPL-D and FEKO yield similarly accurate results as compared to measured far-field gain radiation patterns.
Author(s): D. C. Mooradd, A. J. Fenn, P. T. Hurst
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1216 KB

Title: PEEC-Based Multi-Objective Synthesis of NFC Antennas in the Presence of Conductive Structures
Abstract: Near Field Communication (NFC) techniques are widely used within everyday activities, e.g., contactless payment systems or authentication. Regardless of the application typically the requirements on the antenna structure are manifold. Frequently limitations in the available space make the antenna design quite challenging especially if other conductive structures are close to the NFC antenna. In the present paper we propose to synthesize the geometry of proximity integrated circuit card (PICC) antennas according to class 6 in the presence of nearby metallic structures. The optimization relies on the differential evolution strategy. The computation of the forward problem is based on the partial element equivalent circuit (PEEC) method.
Author(s): T. Bauernfeind, P. Baumgartner, O. Biro, C. Magele, W. Renhart, R. Torchio
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1269 KB

Title: Polarimetric Weather Radar Calibration by Computational Electromagnetics
Abstract: The paper proposes a technique for calibrating a large polarimetric phased array weather radar The focus is on the use of computational electromagnetics. It validates the accuracy of the computations on a scaled-down antenna model and derives calibration parameters for the same model. The proposed technique is demonstrated using the WIPL-D software. The calibration is illustrated with all mathematical concepts required to carry the calibration out. The concept is adapted to use the results of numerical simulations which is part of the paper’s novelty. Additionally, a roadmap of polarimetric phased array calibration is proposed and illustrated.
Author(s): D. Mirkovic, D. S. Zrnic
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1547 KB

Title: Design and Optimization of Two-Dimensional Nano-Arrays for Directive Radiation
Abstract: We consider design, optimization, and computational analysis of nano-arrays involving two-dimensional arrangements of nanoparticles. Similar to their counterparts used at the lower frequencies, nanoantennas can be arranged periodically to achieve directive and/or controllable radiation patterns at optical frequencies. While nanoantenna geometries are usually simple due to restrictions in nanoscale fabrications, their robust analysis still requires accurate simulation tools to model strong plasmonic interactions between particles. We use a full-wave optimization environment based on heuristic algorithms and surface integral equations to optimize two-dimensional nano-arrays and to shape their radiation patterns for diverse nano-optical applications.
Author(s): A. Altinoklu, O. Ergul
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 2356 KB

Title: Efficient Modeling of Towel Bar Antennas Using Model of Distributed Loading along Wires
Abstract: This paper presents an efficient technique to determine equivalents of towel bar antenna dielectric standoffs in the form of wires with distributed loadings using WIPL-D Pro (3-D EM solver) software. Starting from the product, we will determine its basic characteristics and propose simplifications in modeling for further analysis. Benefits of this technique are simplicity of modeling and fast, but still accurate, simulations.
Author(s): M. M. Jovicic, S. N. Tabet, B. M. Kolundzija
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1531 KB

Title: Multi-Fidelity Approach for Polynomial Chaos Based Statistical Analysis of Microwave Networks
Abstract: In this paper, a novel polynomial chaos based approach for the fast statistical analysis of complex microwave structures is proposed. This approach leverages a highly efficient closed form low-fidelity model elicited from the high-dimensional model representation (HDMR) of the network. By cross-cutting the efficiency of this low-fidelity model with the accuracy of general high-fidelity simulations, the accuracy-CPU cost tradeoff for the statistical analysis can be achieved.
Author(s): A. K. Prasad, S. Roy
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1383 KB

Title: Biomedical Magnetic Induction Tomography: An Inhomogeneous Green’s Function Approach
Abstract: Magnetic induction tomography aims to reconstruct the passive electric properties of an object by measuring its scattered magnetic field. Current state-ofthe- art numerical techniques are based on differential formulations such as the finite element method. A formulation based on volume integral equations has not yet been applied to its biomedical field and could improve the reconstruction speed by reducing the number of unknowns. This paper investigates salient characteristics of the approach and offers a solution based on inhomogeneous Green's functions.
Author(s): P. De Tillieux, Y. Goussard
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1343 KB

Title: 28 GHz Propagation Channel Measurements for 5G Microcellular Environments
Abstract: This paper presents results from several 28 GHz propagation channel measurement campaigns performed with a real-time channel sounder that is capable of performing directionally-resolved channel measurements in dynamic environments. We summarize the key results from three measurement campaigns; microcellular in a residential environment, stationarity region, and dynamic scatterers measurements in urban environments.
Author(s): C. U. Bas, R. Wang, S. Sangodoyin, S. Hur, K. Whang, J. Park, J. Zhang, A. F. Molisch
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1563 KB

Title: Analysis of Radio Altimeter Interference due to Wireless Avionics Intra-Communication Systems by Using Large-Scale FDTD Method -Investigation on Airbus A320 Class Passenger Aircraft-
Abstract: Radio altimeters and wireless avionics intracommunication (WAIC) systems are both operated at the frequency band 4,200 MHz–4,400 MHz. Hence, a detailed analysis is required for spectrum sharing in the same band. Firstly, a large-scale finite-difference timedomain analysis is performed to obtain the detailed characteristics of the electromagnetic field (EMF) around the three-dimensional Airbus A320 aircraft model, which assumes that a WAIC device is located inside the cabin. Then, the 4-GHz EMF propagation characteristics are evaluated based on the analyzed results. Finally, the methodology of the interference analysis is discussed based on the obtained EMF characteristics.
Author(s): S. Futatsumori, K. Morioka, A. Kohmura, N. Yonemoto, T. Hikage, T. Sekiguchi, M. Yamamoto, T. Nojima
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1327 KB

Title: Efficient Bayesian Parameter Inversion Facilitated by Multi-Fidelity Modeling
Abstract: We propose an efficient Bayesian parameter inversion technique that utilizes the implicit particle filter to characterize the posterior distribution, and a multi-scale surrogate modeling method called the proper orthogonal decomposition mapping method to provide high-fidelity solutions to the forward model by conducting only low-fidelity simulations. The proposed method is applied to the nonlinear Burgers equation, widely used to model electromagnetic waves, with stochastic viscosity and periodic solutions. We consider solving the equation with a coarsely-discretized finite difference scheme, of which the solutions are used as the low-fidelity solutions, and a Fourier spectral collocation method, which can provide high-fidelity solutions. The results demonstrate that the computational cost of characterizing the posterior distribution of viscosity is greatly reduced by utilizing the low-fidelity simulations, while the loss of accuracy is unnoticeable.
Author(s): Y. Liu
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1185 KB

Title: Robust Feed Modeling of the Asymmetric Planar Mesh Dipole-Type Antenna
Abstract: This paper explores the feed method for the asymmetric planar XY-mesh dipole-type antenna and the modifications needed to prevent its exploitation by automated genetic algorithm (GA) optimization for the application of RFID tag antennas, where the antenna is optimized to the conjugate of the chip impedance. By removing certain feed parameters from the GA optimization and instead making them wavelength dependent, the goal of creating robust models which achieve accurate and matching results between various electromagnetic (EM) simulators, with a focus on the WIPL-D and Axiem EM simulators, was achieved.
Author(s): J. Rayno, D. S. Linden
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1193 KB

Title: Improving Millimeter-Wave Channel Models for Suburban Environments with Site-Specific Geometric Features
Abstract: This paper proposes simple procedures to improve traditional statistical millimeter-wave channel models for suburban environments with site-specific geometric features. Blockages by buildings and vegetation were considered and existing models were verified with measurement data for an emulated microcell deployment. The results indicate that a holistic, network-level approach for channel modeling will help deal with the high dependence of millimeter waves on site-specific features.
Author(s): Y. Zhang, S. Jyoti, C. R. Anderson, N. Michelusi, D. J. Love, A. Sprintson, J. V. Krogmeier
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1398 KB

Title: Electronically Steerable Radiation Pattern of Coupled Periodic Antenna Used Floquet Analysis
Abstract: In this paper we have developed a new Floquet analysis combined to MOM-CEG method to produce 3D electronically controlled antenna arrays. This approach permits to model and optimize the antenna arrays system by the sweeping of radiation beam in several directions. A parametric study on electromagnetic performance of the antenna system based on Floquet states offer a considerable advantages in 3Dsteerable radiation beam, size and directivity. Then smart periodic antenna has been constructed by placing the main beam in the desired direction.
Author(s): B. L. Nader, H. Bilel, A. Taoufik
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 9786 KB

Title: Design of Dual Band Rectifiers for Energy Harvesting Applications
Abstract: Design, simulation and implementation of dual band radio frequency energy harvesting (RFEH) system operating at 900MHz and 1.8GHz is introduced. In the proposed design, RF-DC conversion system is designed to passively amplify the available voltage for rectification by developing a resonator with high quality factor. Passive amplification and rectification are implemented using a combination of clamper and peak detector circuits. Harmonics presented in the rectified output voltage is eliminated by using an innovative two-section dual band transmission line matching network and filter. Energy harvesting system is designed, simulated and measured. Close agreement has been observed between analytical, simulation and measurement results.
Author(s): A. Eroglu, K. Dey, R. Hussain, T. Dey
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1544 KB

Title: A Study of SAR on Child Passengers and Driver Due to Cellphone Connectivity within Vehicle
Abstract: In this work, SAR values in passenger and driver head and body regions due to the presence of one or more cellphones were determined via simulation for the situation in which all vehicle passengers are children. Additionally, the adult driver has access to a hands free cellphone as part of increased in-vehicle connectivity. The FEKO tool, using the Method of Moments, was utilized for simulations.
Author(s): M. J. Lyell, D. N. Aloi
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1116 KB

Title: Estimation of 1090 MHz Signal Environment on Airport Surface by Using Multilateration System
Abstract: This paper is concerned with an estimation of 1090 MHz signal environment on airport surface. Secondary surveillance radar and its applications share 1030 MHz and 1090 MHz. Since many aircraft emit signals with same frequency band, increasing signal amount will be saturated and result in the performance degradation. To meet the aviation requirement, it is important to manage the signal amount. In this paper, focusing on 1090 MHz, we propose an estimation method for signal amount on airport surface, by using multilateration system.
Author(s): J. Honda, Y. Kakubari, T. Otsuyama
File Type: Journal Paper
Issue:Volume: 34      Number: 2      Year: 2019
Download Link:Click here to download PDF     File Size: 1490 KB