ACES Publication Search
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| Title: | ACES Journal May 2016 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2104 KB |
| Title: | ACES Journal May 2016 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 60 KB |
| Title: | ACES Journal May 2016 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 14602 KB |
| Title: | Integration of an Equivalent Aperture Method into Full-wave Electromagnetic Simulation of Airborne Radomes |
| Abstract: | A method is provided for performing efficient, accurate, full-wave electromagnetic simulations of airborne radomes by representing the enclosed antenna with an equivalent aperture field distribution. In this case, the antenna and radome problems are essentially decoupled, and fine meshing details in the antenna region of the problem are eliminated. The equivalent aperture governing equations are discussed, and an algorithm for forming a representative aperture field distribution from far-field radiation patterns is provided. The success of the equivalent aperture method is demonstrated via an example problem. Equivalent aperture results are compared to full-wave simulations of a corresponding fully-detailed slot array antenna. For both the equivalent aperture and corresponding slot array antennas, a 2:1 fineness ratio tangent ogive radome with dielectric constant of 7 and metallic tip is simulated to determine the effects on radiation patterns, loss, and boresight error. Radome insertion loss agreement is achieved to within 0.3 dB or better and boresight error agreement is achieved to within 0.05 deg or better in both elevation and azimuth scan planes for a significantly detuned radome wall. Both transmit-mode and receive-mode formulations of the full-wave radome analysis and their appropriate uses are described. |
| Author(s): | B. L. Cannon, J. W. Jordan |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 647 KB |
| Title: | Calculating Radiation from Arbitrarily Shaped Aperture Antennas Using the Free Space Radiation Integrals |
| Abstract: | A technique is derived by means of which the calculation of radiation from arbitrarily shaped aperture antennas can be greatly simplified compared to the conventional approach. In the conventional approach the null field region of an equivalence problem is typically filled with a conductor, effectively short-circuiting the aperture and the electric surface current density everywhere. The remaining aperture magnetic surface current density, which is known, then radiates in the presence of the conductor and the Green’s function associated with each particular antenna configuration has to be derived, usually a very cumbersome process. In the proposed technique a conductor is again placed within S, but with an infinitesimal small distance between the conductor and S. The image of the electric current density on S is shown to be induced on the conductor and the free space radiation integrals can now be used to solve the radiation problem. Examples are presented to prove the new technique and to demonstrate the mechanics of the equivalence principle when applied to aperture antenna problems. |
| Author(s): | A. J. Booysen |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1640 KB |
| Title: | Field-Simulation Based Engineering of RF Antenna Probes with Non-Uniform Substrates for High-Field Magnetic Resonance Imaging Systems |
| Abstract: | It is proposed to replace RF volume coils in high-field Magnetic Resonance Imaging (MRI) scanners by a microstrip patch antenna system. The performed computational studies have demonstrated an opportunity to form extended 3D volumes of homogenous RF magnetic fields by using a system of placed vis-à-vis two patch antennas. In order to control antenna dimensions and homogeneity of antenna near fields, the substrates of antennas have been engineered by appropriate patterning of high permittivity dielectric inserts. A variety of antennas with engineered substrates responding at 600 MHz for application in 14T MRI scanners have been designed, and the homogeneity of magnetic fields achieved inside the antenna system has been demonstrated. |
| Author(s): | N. P. Gandji, A. V. Palle, G. B. Semouchkin, E. Semouchkina |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 538 KB |
| Title: | Analysis, Design and Demonstration of a Dual-Reflectarray Antenna in Ku-band for European Coverage |
| Abstract: | An accurate technique has been proposed for the analysis of dual-reflectarray antennas, which takes into account the angle of incidence of the field impinging on main reflectarray cells. The technique has been applied to the analysis and design of a contoured beam antenna in Ku-band that provides a European coverage. The reflected field on the sub-reflectarray is computed using Spectral-Domain Method of Moments assuming local periodicity, as customary. The subreflectarray is divided in groups of elements and the radiation from each group is used to compute the incident and reflected fields on the main reflectarray cells. Different degrees of accuracy can be achieved depending on the number of groups considered. A 50-cm antenna demonstrator has been manufactured and measured in a compact range. The measured radiation patterns are in good concordance with the simulations and practically fulfill the coverage requirements with a cross-polar discrimination better than 25 dB in the frequency band 12.975 GHZ - 14.25 GHz. |
| Author(s): | C. Tienda, J. A. Encinar, M. Barba, M. Arrebola |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 792 KB |
| Title: | Out-of-Core Solver Based DDM for Solving Large Airborne Array |
| Abstract: | In this paper, we present a new methodology for an overlapping domain decomposition by using higher-order MoM and out-of-core solver (HO-OCDDM) for analyzing large electromagnetic (EM) problems. This paper proposes two main novelties. First, the required number of meshes is decreased with the application of new higher-order basis function in the discretization of integral equation (IE). As a consequence, the number of unknowns for large EM problems can be reduced. Second, a parallel out-of-core solver is presented in this paper, which can accelerate the matrix filling and solving process without loss of accuracy. The out-ofcore solver breaks the limitation of computer RAM and can be efficiently implemented in domain decomposition method (DDM). |
| Author(s): | Y. Y. Li, X. W. Zhao, H. H. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 936 KB |
| Title: | Comparison Between Genetic and Particle Swarm Optimization Algorithms in Optimizing Ships’ Degaussing Coil Currents |
| Abstract: | This paper presents a comparison between two well-known evolutionary algorithms in optimization of the degaussing coils currents of a ship which are used to reduce the magnetic anomalies of the ferromagnetic hull of the ships induced by the Earth’s magnetic field. To achieve this, first the magnetic anomalies of a simple model of a ship and the effect of each degaussing coil are simulated by using 3D finite element analysis (FEA) software. Then, both genetic algorithm and particle swarm optimization are used to find the best fitting coil currents which can reduce the anomalies of the ship. Using these algorithms is much simpler than optimizing this problem in FEA software in which a huge amount of numerical analyses are needed. This comparison will show which of these algorithms works better in this specific problem. |
| Author(s): | S. M. Makouie, A. Ghorbani |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1269 KB |
| Title: | A Split-Step Pade Solution of 3D-PE Method for EM Scattering from PEC Targets |
| Abstract: | In this paper, the split-step Pade scheme is introduced to solve the three dimensional parabolic equation for EM scattering problems. By implementing the finite differential method, the calculation can be taken from plane to plane along the paraxial direction and a sparse-matrix equation needs to be solved in each transverse plane. In this way, the computational resources can be saved significantly when compared with the rigorous numerical methods. Numerical results demonstrate that the proposed method can obtain accurate results at wider angles up to 45°. |
| Author(s): | Z. He, R. S. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 331 KB |
| Title: | A Miniaturized Polarization Independent Frequency Selective Surface with Stepped Profile for Shielding Applications |
| Abstract: | In this paper, a miniaturized Frequency Selective Surface (FSS) with band-stop characteristics is presented for shielding applications. The FSS is designed to notch at 3.5 GHz frequency in the WiMAX band. The design is composed of a circular metallic patch with identical stepped profile printed on both sides of a low cost FR-4 laminate. The design provides an attenuation of 43 dB at desired resonant frequency. The FSS geometry makes it independent of polarization and it offers stable transmission response. Oblique angle variations don’t affect the unit cell performance, for transverse electric and transverse magnetic modes of polarization. The FSS unit cell is compact with the dimensions of 25 × 25 mm2. The simulated and measured results show good agreement for the proposed design. |
| Author(s): | M. Idrees, S. Buzdar, S. Khalid, M. A. Khalid |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 713 KB |
| Title: | Hybrid Analytical-Numerical Analysis of Plasmonic Photoconductive Antennas |
| Abstract: | Photoconductive antennas (PCAs) have extensive technological applications as terahertz sources. Analysis of the performance of these antennas is typically challenging and time-consuming due to complicated interacting photonic and electromagnetic effects in the semiconductor material. The complexity even further increases in plasmonic PCAs because of the existence of periodic structures. In this paper, a numerical-analytical hybrid model is proposed for analysis plasmonic PCAs. Time-dependence and spatialdependence of the electric field as well as carriers density generated in the semiconductor of plasmonic PCA, are calculated analytically and with finite element method, respectively. The presented model ultimately computes the current generated in the electrodes of plasmonic PCAs. Using this model, the performance of a typical plasmonic PCA as an example is investigated, and model results are validated by measurement results currently existing in the literature; though the model can also be used in the performance analysis of plasmonic PCAs with more complex periodic structures. |
| Author(s): | M. Khorshidi, G. Dadashzadeh |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 757 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: | Active Metamaterial Transmission Line with Gain in SiGe BiCMOS Technology |
| Abstract: | We report the realization of an active composite right/left-handed (CRLH) metamaterial transmission line (TL) with gain. By employing the transistors in SiGe BiCMOS technology, an active CRLH TL has been realized exhibiting net gain, wideband and flat S-parameter characteristics. Effective electromagnetic parameters of the active CRLH TL, including complex propagation constant ?, effective permittivity ?eff, effective permeability ?eff and index of refraction n are extracted, which reveal the left handed properties of the active CRLH TL. The electric plasma frequency fpe and the magnetic plasma frequency fme are observed in the proposed TL. |
| Author(s): | C. X. Zhou, Y. Li, Y. Z. Xiong, W. Wu |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 496 KB |
| Title: | A Single-Layer Multi-Band Reflectarray Antenna in X/Ku/K-Bands |
| Abstract: | A new center-fed tri-band reflectarray antenna is presented in this paper. Elements of the reflectarray antenna are circular rings and patches loaded with slots. The proposed antenna operates in three bands (X, Ku and K). The introduced element, has been optimized to achieve large linear phase range at the three bands. Phase compensation is achieved by varying the size of elements. Height of the horn antenna has been optimized to get maximum gain and bandwidth at the three bands. |
| Author(s): | Z. Hamzavi-Zarghani, Z. Atlasbaf |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 562 KB |
| Title: | Design and Realization of a Wideband Microstrip Filter Using Signal- Interaction Techniques |
| Abstract: | The signal-interaction techniques are adopted in this paper to design a novel wideband microstrip filter. The signal is transmitted from input port to the output one through two transmission paths in parallel which is composed of a wideband 180° inverter based on microstrip line and a 3?/4 transmission line. Besides, two ?/4 shorted-ended lines is employed to improve the passband transmission performance of the BPF (Bandpass Filter). It is demonstrated from the simulation and measurement results of the novel BPF that three transmission zeros leading to the good harmonic suppression performance are achieved for the BPF operating from 0.99 to 2.51 GHz with 3-dB fractional bandwidth of 86.8%. |
| Author(s): | L. Zhou, Y. Yin, W. Hu, X. Yang |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1229 KB |
| Title: | Harmonic Suppression of Parallel Coupled-Line Bandpass Filters using Defected Microstrip Structure |
| Abstract: | This paper presents a novel miniaturized parallel coupled-line bandpass filter by etching some slot resonators on the strip for suppressing the first spurious response. These slots perform a serious LC resonance property in certain frequency and suppress the spurious signals. By properly tuning these slot dimensions, multiple closed notches can be generated in the vicinity of spurious harmonic and a wide stopband can be obtained. Slot on the strip that is called Defected Microstrip Structure (DMS). The DMS interconnection disturbs the current distribution only across the strip, thereby giving a modified microstrip line with certain stop band and slow-wave characteristics. The simulation and measurement of a 4.7 GHz prototype bandpass filter are presented. The measured results show a satisfactory rejection level more than 30 dB at first spurious passband without affecting the passband response. Good agreement between the experimental and full-wave simulated results has been achieved. |
| Author(s): | M. Naser-Moghadasi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 540 KB |
| Title: | Fast Simulation of Microwave Devices via a Data-Sparse and Explicit Finite-Element Time-Domain Method |
| Abstract: | An unconditionally stable and explicit finite-element time-domain (FETD) method is presented for the fast simulation of microwave devices. The Crank-Nicolson (CN) scheme is implemented leading to an unconditionally stable mixed FETD method. A data-sparse approximate inverse algorithm is introduced to provide a data-sparse way to approximate the inverse of FETD system matrix which is dense originally. This approximate inverse matrix can be constructed and stored with almost linear complexity, and then the FETD method can be computed explicitly at each time step without solving a sparse linear system. An efficient recompression technique is introduced to further accelerate the explicit solution at each time step. Some microwave devices are simulated to demonstrate the efficiency and accuracy of the proposed method. |
| Author(s): | T. Wan, L. Du, J. Zhu |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 444 KB |
| Title: | Design and Implementation of Claw Pole Alternator for Aircraft Application |
| Abstract: | Nowadays most of the countries develop special aircraft and utilize them for defense applications. This paper deals with the modeling, simulation, and implementation of the Claw pole synchronous generator. The design specifications of the designed generators are compatible for aircraft applications. The main objective of this work was to estimate and test the performance of the claw pole alternator under high speed operation. The electromagnetic design of the machine was carried out using Finite Element Analysis (FEA) software. The performance of the machine was tested under laboratory environment. The results of experimentation were compared with those of simulation and proved. |
| Author(s): | D. Arumugam, P. Logamani, S. Karuppiah |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 787 KB |
| Title: | CSC-SR Structure Loaded Electrically Small Planar Antenna |
| Abstract: | This paper aims at a new planar left hand metamaterial structure for loading planar microstrip antenna (MPA). A metallic planar dual turn spiral resonator (DTSR), useful for artificial magnetic media design, is merged with a capacitive loaded strip (CLS) on the same plane to design capacitive strip coupled spiral resonator (CSC-SR) unit cell structure. Apart from having small size, the new structure offers advantages of demonstrating wide left handed frequency band, and simplicity of fabrication being on same plane, hence indicating supremacy of its inclusion in engineering of left hand metamaterials. The size of proposed antenna is 0.177? × 0.243?. The electro-magnetic coupling of the proposed structure causes the MPA to resonate at lower frequency of 13.25 GHz due to loading effects. The proposed novel antenna is able to give better performance in terms of return loss, gain and fractional bandwidth and is suitable for satellite communication. The measured results are presented to validate simulated model of the proposed antenna. |
| Author(s): | R. Marwaha, A. Marwaha |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 899 KB |
| Title: | A Switched Beam Antenna Array with Butler Matrix Network using Substrate Integrated Waveguide Technology for 60 GHz Radio |
| Abstract: | A switched beam antenna array based on substrate integrated waveguide (SIW) technology is designed and simulated for 60 GHz communications. The antenna array is fed by 4x4 planar butler matrix network in order to achieve the switched beam characteristic. Each of the components is designed and verified through simulations in electromagnetic field simulation tools, CST MWS and HFSS. The components are integrated later to form the switched beam antenna array. The return losses and isolations are better than 10 dB from 57 GHz to 64 GHz for all of the input ports. The peak gain for the switched beam antenna array is 18 dBi at 60 GHz. |
| Author(s): | N. Tiwari, T. R. Rao |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 5 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1422 KB |