ACES Publication Search





There are 13 search results for:



Title: ACES Journal September 2014 Cover
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 1317 KB

Title: ACES Journal September 2014 Front/Back Matter
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 23 KB

Title: ACES Journal September 2014 Full
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 7609 KB

Title: Electromagnetic Device Optimization: The Forking of Already Parallelized Threads on Graphics Processing Units
Abstract: In light of the new capability to fork an already parallelized kernel on a GPU, this paper shows how the use of the parallelization capabilities of a PC’s Graphics Processing Unit (GPU) makes the finite element design of coupled problems (such as the electroheat shape optimization problems we work with) realistic and practicable in terms of computational time.
Author(s): S. R. H. Hoole, S. Sivasuthan, V. U. Karthik, A. Rahunanthan, R. S. Thyagarajan, P. Jayakumar
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 713 KB

Title: An UWB Microstrip-Fed Slot Antenna with Enhanced Bandwidth and WLAN Band-Notched Characteristics
Abstract: In this paper, a compact UltraWideband (UWB) slot antenna with band-notched performance is presented. In order to increase the impedance bandwidth of an ordinary slot antenna, we use a pair of S-shaped slots in the ground plane that with this structure, a new resonance at the higher frequencies can be achieved and a wide usable fractional bandwidth of more than 130% is provided. Additionally, by using a protruded Eshaped strip inside the square-ring radiating patch, a frequency band-notched function has been obtained. The designed antenna has a small size of 20×20 mm2 while showing the radiation performance in the frequency band of 3.13 to over 14.3 GHz, with a band rejection performance in the frequency band of 5 to 6 GHz. Simulated and experimental results obtained for this antenna show that it exhibits good radiation behavior within the UWB frequency range.
Author(s): Y. Ojaroudi, S. Ojaroudi, N. Ojaroudi
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 829 KB

Title: A Novel Multi-Way Power Divider Design with Enhanced Spurious Suppression
Abstract: In this article, a multi-way Bagley Polygon power divider using a novel technique for enhanced harmonic suppression is presented. In this technique, a T-shaped transmission line with open stub is designed to replace each quarterwavelength transmission line of the conventional Bagley Polygon power divider. The proposed power divider characterizes arbitrary multiharmonic suppression in theory, and not only exempt from backside etching or lumped reactive components, but also offering a high level of attenuation over a wide stop band bandwidth. The closed form design equations of the proposed Bagley Polygon power divider have been obtained by rigorous derivation. For verification, a 5-way Bagley Polygon power divider is fabricated and measured. The bandwidth for the suppression of the single third harmonic above 20 dB approximates 37% and enhanced the second-, third-, and fourth-harmonic above 30 dB over 3 GHz at operation frequency of 1.0 GHz.
Author(s): J. Li, Y. Liu, S. Li, C. Yu, Y. Wu
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 595 KB

Title: On the Attenuation of the Perfectly Matched Layer in Electromagnetic Scattering Problems with the Spectral Element Method
Abstract: Although Spectral Element Method (SEM) has been applied in the modeling of boundary value problems of electromagnetics, its usage is not as common as the Finite Element or Finite Difference approaches in this area. It is well-known that the Perfectly Matched Layer (PML) approach is a mesh/grid truncation method in scattering or radiation applications where the spatial domain is unbounded. In this paper, the PML approach in the SEM context is investigated in two-dimensional, frequency-domain scattering problems. The main aim of this paper is to provide the PML parameters for obtaining an optimum amount of attenuation in the scattered field per wavelength in the PML region for LegendreGauss-Lobatto grids. This approach is extended to the analysis of SEM accuracy in scattering by electrically large objects by taking the free space Green’s function as the building block of the scattered field. Numerical results presented in this work demonstrate the ability of achieving a high degree of accuracy of SEM as compared to other finite methods, as well as the successful applicability of the PML in electromagnetic scattering problems in terms of the optimum attenuation factors provided in this work.
Author(s): I. Mahariq, M. Kuzuoglu, I. H. Tarman
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 667 KB

Title: A Compact 2-18 GHz Halved Vivaldi Antenna
Abstract: A compact, broadband, halved planar Vivaldi antenna has been proposed in this paper. The halved Vivaldi antenna is located on a large metal plane vertically, and connected to the metal plane through feed-line and short-line. The proposed antenna was designed, fabricated, and tested. Experimental and simulated results show that the proposed halved Vivaldi antenna has a wide bandwidth from approximately 1.44 to 18.5 GHz, and a small size of only 30 mm × 60.5 mm. Moreover, the designed antenna can provide excellent characteristics, including directive radiation characteristics and vertically polarized radiation pattern. These results prove that the proposed antenna should be useful in many metal surface-mounted communication systems, such as missile, unmanned aerial vehicles, and the like.
Author(s): P. Wang, G. Wen, Y. Huang, H. Zhang
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 1196 KB

Title: Multi-Resonance Monopole Antenna with Inverted Y-Shaped Slit and Conductor-Backed Plane
Abstract: This manuscript introduces a new design of multi-resonance monopole antenna for Ultra-Wideband (UWB) applications. The proposed antenna consists of an ordinary square radiating patch and a modified ground plane with inverted Y-shaped slit and conductor-backed plane, which provides a wide usable fractional bandwidth of more than 135%. By cutting an inverted Y-shaped slit in the ground plane and also by embedding an Inverted Y-shaped conductorbacked plane in the feed gap distance, additional (third and fourth) resonances are excited and hence much wider impedance bandwidth can be produced; especially at the higher band. By obtaining these resonances, the usable lower frequency is decreased from 3.12 to 2.9 GHz, and also the usable upper frequency of the presented monopole antenna is extended from 10.3 to 14.85 GHz. 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 2.83 to 14.87 GHz, which is suitable for UWB systems.
Author(s): S. Ojaroudi, Y. Ojaroudi, N. Ojaroudi
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 738 KB

Title: Analytical Estimation of Radar Cross Section of Arbitrary Compact Dipole Array
Abstract: This paper presents the scattering estimation and analysis of an arbitrary phased array with parallel, centre-fed dipole elements, in the presence of mutual coupling. The total Radar Cross Section (RCS) of the uniform dipole array is computed by considering the signal reflections within the array system. The results are shown for two types of feed networks, viz. series feed and parallel feed. The scattering due to higher order reflections and edge effects are neglected. The analytical formulae presented for array RCS emphasize the dependence of scattered field on the design parameters, like dipole length, interelement spacing, geometrical and electrical properties of phase shifters, couplers and terminal impedances. The results indicate that the mutual coupling effect on the overall RCS pattern is identical for both equal and unequal length dipole arrays. This paper identifies the design parameters that can be optimized towards the RCS control of phased array. These parameters include dipolelength, geometric configuration and terminal impedance.
Author(s): H. L. Sneha, H. Singh, R. M. Jha
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 1191 KB

Title: A Novel Dual-Mode Wideband Band Pass Filter
Abstract: A novel Wideband (WB) Bandpass Filter (BPF) with improved passband performance using a Defected Ground Structure (DGS) is presented in this paper. The proposed BPF is composed of two novel basic WB resonators and six Dumbbell-Shaped (DS) DGSs. By cascading resonators we can achieve better skirt characteristics, and by using DS-DGSs under interdigital coupled I/O lines we can improve the return loss within the passband. The simulated and measured results are found in good agreement with each other showing a wide passband from 4.93 to 11.62 GHz, a wide upper stopband with around 25 dB attenuation up to 20 GHz, and sharp roll-offs around 0.03 in lower and upper edges.
Author(s): A. Ahmadi, S. V. Makki, A. Lalbakhsh, S. Majidifar
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 632 KB

Title: Design of a Broadband Microstrip-to-Microstrip Vertical Transition
Abstract: A broadband microstrip-to-microstrip vertical transition is presented in this paper. The proposed transition consists of two quarterwavelength microstrip stubs and a halfwavelength slotline Stepped Impedance Resonator (SIR) on the common ground plane. The low-impedance section of the microstrip stub is formed by three single arms connecting in parallel, while the high-impedance section of slotline SIR is formed by four single arms connecting in series. A sample transition is designed and measured. Experimental results indicate that over 143% bandwidth with better than 10 dB return loss and below 2 dB insertion loss can be achieved.
Author(s): Z. Tao, J. Wang, Y. Dou
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 393 KB

Title: CPW-Fed Fractal Monopole Antenna for UWB Communication Applications
Abstract: This paper presents the results of a novel fractal monopole antenna that exhibits UltraWideband (UWB) performance. Higher order iteration of the fractal motif constituting the antenna was analyzed and its performance evaluated in order to optimize the antenna’s characteristics. Compared to a typical circular monopole antenna, the proposed antenna generates reflection-coefficient resonances that significantly improve its impedance bandwidth by 160%. The antenna’s measured performance conforms to the desired UWB specifications.
Author(s): Y. Zehforoosh, M. N. Moghadasi
File Type: Journal Paper
Issue:Volume: 29      Number: 9      Year: 2014
Download Link:Click here to download PDF     File Size: 930 KB