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Title: ACES Journal October 2013 Full Issue
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 19665 KB

Title: ACES Journal October 2013 Front/Back Matter
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 50 KB

Title: High-order Treatment of Junctions and Edge Singularities with the Locally-corrected Nyström Method
Abstract: High order techniques are known to be effective for the electromagnetic analysis of smooth structures. In the following, high order representations developed for the current density at edges and junctions are incorporated into the locally-corrected Nyström method. Conducting structures used for purposes of illustration include a strip, a structure with three fins and a junction, and a hexagonal cylinder. Results suggest that the accuracy of the numerical results obtained with the new approach is comparable to that obtained for problems with smooth surfaces.
Author(s): M. M. Bibby, A. F. Peterson
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
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Title: Minimizing The 3D Solenoidal Basis Set in Method of Moments Based Volume Integral Equation
Abstract: A method for completely minimizing a 3D-solenoidal basis set, and identifying its linearly independent basis functions in method of moments (MoM) based volume integral equation (VIE) is presented. The method uses the connecting information of the geometric mesh and the properties of the 3D solenoidal basis function to remove the null space of the basis set. Consequently, the approach is not prone to numerical inaccuracies due to finite machine precision resulting from matrix manipulations. In addition, our method is not restricted to simply connected or contiguous mesh regions; it is applicable to a wide variety of complicated mesh regions featuring holes and voids. Finally, an expression for determining the minimum number of linearly independent solenoidal basis functions in a given tetrahedral mesh is presented.
Author(s): A. Obi, R. Lemdiasov, R. Ludwig
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 560 KB

Title: Simple and Efficient BZT-Higher-Order PML Formulations for the Metal Plate Buried in Three-Dimensional Dispersive Soil Space Problems
Abstract: Efficient and unsplit-field higher-order PML formulations using the stretched coordinate perfectly matched layer (SC-PML) formulations and the bilinear Z-Transform (BZT) method are presented for truncating the finite-difference time-domain (FDTD) lattices. This method is completely independent of the material properties of the FDTD computational domain and hence can be applied to the modeling of arbitrary media without any modification because of the D-B constitutive relations used. The higher-order PML has the advantages of both the conventional PML and the complex frequency-shifted PML (CFS-PML) in terms of absorbing performances. Two 3D FDTD simulations of the metal plate buried in dispersive soil space FDTD domains have been carried out to validate these formulations. It is shown that the proposed PML formulations with the higher-order scheme are efficient in terms of attenuating both the low- frequency propagating waves and evanescent waves and reducing late-time reflections.
Author(s): N. Feng, Q. H. Liu, C. Zhu
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 247 KB

Title: Analysis of EM Scattering from 3D Bi-Anisotropic Objects above a Lossy Half Space Using FE-BI with UV Method
Abstract: In this paper, the finite-element boundary integral (FE-BI) method with UV method is applied to analyze the electromagnetic scattering from arbitrary three-dimensional bianisotropic objects located above a lossy half space. The form of electric field in bi-anisotropic materials is provided and cast into linear equations by finite element method (FEM), which is valid for any complex materials. The boundary integral equation (BI) is used to truncate the computational domain by using a half-space dyadic Green's function via the discrete complex image method (DCIM). A fast numerical approach, the UV method, is employed to decrease the memory requirement and the total CPU time for FE-BI solution. Numerical results are carried out so as to validate our developed algorithm. Further, the effects of different material parameters on the scattering characteristics of typical bi-anisotropic object in half space are examined and compared.
Author(s): J. Zhu, M. M. Li, Z. H. Fan, R. S. Chen
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 297 KB

Title: Linear Dielectric Resonator Array Fed by N-Way Bow-Tie Shaped Dielectric Resonator Power Divider
Abstract: The concept of using high order modes of a bow-tie shaped dielectric resonator in the design of N-way power divider is presented in this paper. The design of 6-way power divider operating at X-band frequency range is illustrated, simulated and tested for concept validation. The combination of probe type excitation and microstrip technology is used to excite an Hpolarized resonating mode around 10 GHz. Both input matching and in phase tapered power distribution are experimentally maintained within 150 MHz frequency band around the resonant frequency. Measured scattering parameters magnitude and phase of the proposed 7-port structure are shown to verify the expected simulation results. Also, the proposed power divider is used to excite an antenna array of six rectangular dielectric resonators using narrow slots coupled to the power divider output through microstrip lines. Good agreement between simulated and measured results is obtained for application validation.
Author(s): L. Hady Salman, A. Kishk, D. Kajfez
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 1725 KB

Title: Modeling of Weakly Conducting Thin Sheets in the Discontinuous Galerkin Method for Shielding Effectiveness Evaluation
Abstract: This paper presents a modeling of weakly conducting thin sheets in the time domain discontinuous Galerkin method. This interface condition is used to avoid the mesh of resistive sheets in order to evaluate the shielding effectiveness in high frequency electromagnetic compatibility problems. This condition is valid when the thickness of the sheet is smaller than the skin depth. This approach is validated by a comparison with an analytical solution. A 1D two sheets example, 2D and 3D cavities are treated to illustrate the efficiency of the condition.
Author(s): M. Boubekeur, A. Kameni, A. Modave, L. Bernard, L. Pichon
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 758 KB

Title: Compact CPW-Fed Antenna with Circular Polarization Characteristics in WLAN Frequency Band
Abstract: A novel co-planar waveguide (CPW)- fed antenna with circular polarization (CP) characteristics in the 5.1 GHz ? 5.8GHz is presented. By adding a vertical stub and a rotated L shaped stub to the antenna structure, a bandwidth of 5 GHz ? 8GHz (46 %) for S11 < -10 dB is achieved and also circular polarization characteristics is generated in the 5.1 GHz ? 5.8 GHz, which completely covers the wireless local area network (WLAN) frequency band. The antenna has a very simple structure and occupies a compact area of 25 × 25 × 1 mm3. The very simple structure and small size are of the marvelous merits of the proposed antenna. The antenna design process, impedance bandwidth and axial ratio (AR) bandwidth enhancement process are discussed in detail.
Author(s): M. Majidzadeh, J. Nourinia, Ch. Ghobadi
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 1377 KB

Title: Comprehensive Parametric Study of a Novel Dual-Band Single Feed Planar Inverted-F Antenna
Abstract: This paper presents a new configuration of a dual frequency, single feed, planar inverted-F antenna, which is suitable for implementation in different handsets. A parametric study, using finite element simulation software, high frequency structure simulator, has been carried out on each of the frequencies of this antenna and closed formulas in terms of antenna parameters have been obtained, which makes the designing process much easier. The proposed antenna has been fabricated according to the obtained formulas. Both, numerical simulation and experimental data are presented.
Author(s): T. Yousefi, N. Komjani
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 1156 KB

Title: Detail-Oriented Design of a Dual-Mode Antenna with Orthogonal Radiation Patterns Utilizing Theory of Characteristic Modes
Abstract: In this paper, theory of characteristic modes (TCMs) is used to perform modal analysis of a trapezium-shaped PEC plate. So it follows that a wide-spread overview about the electromagnetics behavior of the plate is provided. The first seven characteristic currents and corresponding resonance frequencies of the structure are obtained. All modes are orthogonal to each other. By applying the reactive loading, the first two modes are forced to be resonating close to each other at frequency of about 3.5 GHz, which is suitable for WiMax applications. To excite aforementioned modes on the structure, an appropriate configuration of microstrip feed lines is utilized. Due to the orthogonality property of current modes, the created radiation patterns are also orthogonal to each other. Since two characteristic currents are excited on the structure’s body, it is expected to achieve two orthogonal radiation patterns too, which could result in a dual-mode antenna. To carry out the above-mentioned modal analysis, a specific method of moments (MoM) code has been developed and applied. The proposed antenna is simulated by well-known full-wave package Ansoft HFSS and results clarification of the expectations about the orthogonality in patterns.
Author(s): A. Araghi, G. Dadashzadeh
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 2237 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: 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: Analysis and Optimization of a 2-D Magnet Array with Hexagon Magnet
Abstract: This paper introduces the hexagon permanent magnets, which are in ??- or ??- axis magnetized directions to the 2-D permanent magnet array for planar motor. Through the scalar magnetic potential equation, finite element method and effective amplitudes, the harmonic and analytical models are derived and verified. The reduction of the higher harmonics of ??-component of the magnetic flux density with hexagon magnets is verified. Low higher harmonics of ??- component of the magnetic flux density with hexagon magnets is optimized by the genetic algorithm. Comparing with the 2-D Halbach magnet arrays, the new magnet array has larger ??- component of the magnetic flux density and smaller higher harmonics of ??-component of the magnetic flux density, which can reduce the force ripples of planar motor.
Author(s): G. Liu, Y. Zhou, R. Zhou, W. Ming, L. Huo
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 1231 KB

Title: GHz-Frequency Electromagnetic Interference Suppression Technique using Magnetic Absorber for Hard Disk Interconnector
Abstract: An electromagnetic interference (EMI) suppression technique for gigahertz (GHz) frequency region of hard disk interconnector, namely trace suspension assembly interconnector (TSAI) is presented. The BSR-1 absorber is selected and filled in between conductor traces of the interconnector. The attenuation of radiated and conducted EMIs are calculated and analyzed by using simulation software based on finite integral technique. From the results, it is found that the proposed technique can suppress radiated EMI from 16 ?V to 0.5 ?V in all frequency regions up to 20 GHz and the conducted EMI can be suppressed up to 0.7 Watt in a range of 0.9 GHz  4.0 GHz with the same structure of TSAI.
Author(s): S. Osaklang, A. Keawrawang, A. Siritaratiwat, V. Ungvichian, R. Sivaratana, K. Prachumrasee, A. Kruesubthaworn
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 1374 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: Microstrip Patch Antenna Covered With Left Handed Metamaterial
Abstract: We present gain characteristics of microstrip patch antennas covered with metamaterial substrate composed of split-ring resonators (SRRs) and metallic strip. To determine the performance of the SRR-metallic strip mounted on microstrip patch antenna, the metamaterial has been proposed as an effective medium with extracted constitutive parameters. Simulation results are supported by experimental measurements. The experimental results confirm that the metamaterial covered patch antenna improves gain by an amount of -5.68 dB (% 60.3) as well as radiation pattern (-8 dB to +20 dB) at WLAN communication.
Author(s): E. Dogan, E. Unal, D. Kapusuz, M. Karaaslan, C. Sabah
File Type: Journal Paper
Issue:Volume: 28      Number: 10      Year: 2013
Download Link:Click here to download PDF     File Size: 1671 KB