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Title: ACES Journal September 2017 Cover
Abstract: ACES
Author(s):
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
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Title: ACES Journal September 2017 Front/Back Matter
Abstract: ACES
Author(s):
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
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Title: ACES Journal September 2017 Full
Abstract: ACES
Author(s):
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 12831 KB

Title: Broadband Dual-Use Array with Planar Log Periodic Dipole Elements
Abstract: This paper presents a phased array consisting of 8 horizontally positioned planar log periodic dipole array antennas for use over the frequency range of 800 to 1,300 MHz. The array is dual use in that it can either scan in azimuth with a narrow beam or be forward looking with a null-filled broad beam. To achieve the broad beam, the 8-element array is divided into two 4-element subarrays. The main beam of each subarray is then pointed near the first null of the 8-element uniform array radiation pattern to “fill” the nulls. The results for the narrow beam configuration produce an azimuthal beamwidth of 15° with 15 dBi of gain, and the null- filled configuration produces an increase in azimuthal beamwidth to 55° (40° increase) with a peak gain of 10 dBi (loss of 5 dB). Note that this paper only presents the antenna development and array testing but not any system hardware.
Author(s): S. A. McCormick, W. O. Coburn
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
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Title: Study, Design and Fabrication of a CPW Fed Compact Monopole Antenna with Circular Polarization for Ultra Wide Band Systems Application
Abstract: A compact circularly polarized square slot antenna (CPSSA) is presented in this paper, which is appropriate for UWB applications requiring high data rate transmission. This antenna operates across 2.8 GHz to 10.8 GHz with an impedance bandwidth (IBW) of 117.6% for VSWR less than or equal to 2. The antenna consists of a trapezoidal shaped radiation patch which is fed through a coplanar waveguide (CPW) and includes two inverted L-shaped ground arms at the two opposite corners of the slot to excite two orthogonal resonant modes for circular-polarization (CP) radiation. Furthermore, two square slits at the two other opposite corners of the slot are applied to enhance its IBW. The antenna exhibits CP bandwidth of 50.5% across 3.7 GHz-6.2 GHz, which is suitable for WLAN, WiMAX and C-bands. In addition, the antenna has a considerably compact volume of 25×25×0.8 mm3. The measured and simulated results confirm the usefulness of the antenna for practical applications.
Author(s): M. Shokri, S. Asiaban, A. Amiri
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
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Title: Modal Analysis of Wave Propagation in Straight and Curved Arched Tunnel Based on Equivalent Rectangular Tunnel Model
Abstract: In this paper, a model is presented to simulate wave propagation in straight and curved tunnels with arched cross section with imperfectly conducting walls. The model is based on treating the tunnels as a rectangular waveguide with imperfectly conducting walls, where the arched cross section of the tunnels is approximated with equivalent rectangular cross section. A scenario is considered to check the accuracy of this model. This scenario is verified by comparing experimental and numerical simulation results. Good agreement between the proposed model and the experimental results is obtained.
Author(s): H. M. El-Maghrabi, S. F. Mahmoud, M. El-Said
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
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Title: Improper Integrals Calculations for Fourier Boundary Element Method
Abstract: This paper presents a method of regularization for the numerical calculation of improper integrals used in different formulations of Boundary Element Method (BEM). The main attention of the readers we would like to focus on Fourier Formulation of BEM. The singular integrals arise when for discretization the elements of a higher order than zero are used. Very often in the Diffusive Optical Tomography for infant head modeling, triangular or square curvilinear boundary elements of the second order are used [12,14], hence, our interest in the subject of effective and accurate calculation of singular integrals. Even for the classical formulation of BEM such a problem is extremely difficult [1]. Some authors believe that the practical application possesses only flat triangular boundary elements of zero-order, and although there is some truth in this statement, the elements of the second order show a significant advantage [10,12] in Diffusion Optical Tomography (DOT) for example. This issue becomes even more interesting when we deal with the Galerkin BEM formulation offering the possibility of matrix of coefficients symmetrisation, which has fundamental importance for inverse problems. This matter becomes critical when we start to consider the Fourier BEM formulation, introduced by Duddeck [5]. His approach provides the possibility of a solution in the case which has no fundamental solution. The light propagation, which is described by the Boltzmann equation (see Arridge [2]) is such a case. Currently and most commonly, the Boltzmann equation is approximated by the diffusion equation in strongly light scattering media [10]. In the author’s opinion, the problem of numerical integration of improper integrals has not yet been fully exhausted in the classic and Galerkin BEM formulation but the Fourier BEM formulation still expects the proposals of the effective solutions. Such an offer we would like to present in this paper.
Author(s): J. Sikora, K. Polakowski, B. Panczyk
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
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Title: Towards Wideband Hyperthermia Treatment System
Abstract: This paper presents an overview of design and functionality of the essential modules proposed to build a wideband hyperthermia system. Description is provided of the waveform shaper, power amplifier and applicator array modules. Big data analysis is presented to accelerate energy localization depending on a time reversal technique. Simulation results are provided assuming a cylindrical head phantom characterized with wideband dispersive tissue properties, and the obtained field maps are shown in different planes to visualize energy localization process. Results reveal that wideband operation has the potential to enhance energy localization in deep tumor regions while eradicating hot spots, as compared to conventional narrowband systems.
Author(s): N. Nizam-Uddin, W. Alkadri, W. A. Malik, I. Elshafiey, A. F. Sheta
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 2587 KB

Title: Parallel Higher-Order Method of Moments with Efficient Out-of-GPU Memory Schemes for Solving Electromagnetic Problems
Abstract: A distributed parallel Higher-order Method of Moments (HoMoM) for solving electromagnetic problems on CPU/GPU clusters is presented. An MPI/ OpenMP/CUDA parallel framework based on the GPU context technique is designed. An out-of-GPU memory scheme is employed to break the limitation of the GPU memory. To improve the performance of data transferring between main memory and GPU memory, an overlapping scheme based on asynchronous technique and CUDA streams is adopted. In comparison with the parallel CPU version only, numerical results including a metallic airplane and an airborne array with dielectric structures demonstrate the high performance of the proposed method.
Author(s): Z. Lin, Y. Chen, X. Zhao, D. Garcia-Donoro, Y. Zhang, H. Zhang
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 1747 KB

Title: Circularly Polarized Aperture Coupled Zeroth Order Resonance Antenna for mm-Wave Applications
Abstract: In this work, a millimetre-wave aperture–coupled antenna was offered by mode synthesis. In order to increase half power beam width (HPBW), the present study united a TM010 mode, which was generated by aperture slot of substrate integrated waveguide (SIW), and a zeroth-order resonance (ZOR) mode of a metamaterial polarizer mushroom. The results were confirmed by an equivalent circuit and a full wave simulator. Moreover, to prevent mm-wave fed loss, the study made use of a SIW feed with a slot which reduced the interference between a feed and a mushroom metamaterial structure as a polarizer antenna. The proposed antenna was fabricated and measured at 35 GHz. The simulated results roughly agreed with the measured results.
Author(s): S. Karamzadeh, V. Rafiei, H. Saygin
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 2158 KB

Title: An Improved Design of Equal-Split Filtering Divider with Integrated Coupled-Line Band-Pass Filter
Abstract: A novel methodology is proposed for achieving good output port isolation and return loss in a micro-strip filtering divider design with integrated coupled-line (CPL) band-pass filter (BPF). The designed filtering divider shows improved performance parameters as compared to previously reported work. It is proposed that by incorporating an extended transmission line (TL) and a conventional resistor as isolation elements, in addition to good even mode response (i.e., insertion loss IL, and input port return loss RL), the odd mode response (i.e., output port RL and isolation) can simultaneously be improved. In addition, two transmission zeros are realized in the vicinity of the pass band providing a reasonable skirt. Firstly, the coupled-line filter (CPLF) is matched to 70.7 omega and subsequently integrated in place of conventional quarter wavelength transformers in a Wilkinson Power Divider (WPD) for equal division. Under these matched conditions, it is shown that a TL section and isolation resistor sufficed to achieve a reasonable output port return loss (RL) and isolation in the resulting filtering divider. Experimental validation of the proposed methodology comes from the measurements results of the fabricated CPL filtering divider designed at 3 GHz conforming reasonably to the simulated ones. For instance, 1 dB fractional bandwidth of 15.3%, port isolation of better than 31 dB and good out-of-band performance up to 2.67f0 were experimentally achieved.
Author(s): Z. B. Khan, H. Zhao
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 1675 KB

Title: High Selectivity Dual-band Bandpass Filters Using Dual-mode Resonators
Abstract: Two high selectivity dual-band bandpass filters using dual-mode resonators are proposed in this paper. Four and six transmission zeros near the passbands can be easily achieved for two dual-band bandpass filters. A transmission zero located in the two passbands is used to realize good isolation for the two passbands. Two prototypes with center frequencies located at 1.93, 2.42 GHz, and 2.04, 2.32 GHz with upper stopband insertion loss greater than 20 dB are designed and fabricated. The two proposed dual-band bandpass filters show high passband selectivity, good out-of-band suppression.
Author(s): R. Yin, W. Feng, W. Che
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 2282 KB

Title: Optimization of Wireless Power Transmission Systems with Parasitic Wires
Abstract: We present a rigorous optimization method to design wireless power transmission (WPT) systems. In order to optimize the power coupled to the receiver, reactive parasitic components are integrated into the system. Simulated annealing is implemented in conjunction with the method of moments to determine the optimum parameters for the design. By carefully adjusting the geometry, size, position and properties of the parasitic wires, it could be seen that the peak efficiency and effective distance for power coupling could be significantly improved. The result shows that the implementation of a square parasitic wire gives better performance than a circular one. A WPT system with a square reactive wire gives respectively a 0.79% and 0.07 lambda improvement in peak efficiency and effective distance compared to its zero-impedance counterpart. By inserting two square reactive wires with the transmitter sandwiched in between, the peak efficiency and effective distance are found to have increased respectively by 3.37% and 0.18 lambda, compared to that with a single reactive wire.
Author(s): K. H. Yeap, A. R. C. Cheah, K. Hirasawa, K. C. Yeong, K. C. Lai, H. Nisar
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 1881 KB

Title: Low-profile Hybrid-mode Antenna Providing Near-hemispherical Field-of-view Coverage
Abstract: The hybrid-mode model (HMM) combining monopole and dipole radiation modes can provide near-hemispherical coverage but has a high profile. To reduce the profile of HMM, a modified HMM is presented in this paper using a dipole radiator and a magnetic current loop radiator. Based on the modified model, a low-profile on-board antenna is proposed. When the side length of the ground is infinite, the 3-dB beamwidths in the xz plane and yz plane of the proposed antenna are both 180°. When the side length of the ground is finite, the proposed antenna can provide a near-hemispherical field-of- view coverage. The design example demonstrates the practicability of the modified HMM and the proposed antenna can be used in wide-angle scanning arrays and rich-multipath communication systems.
Author(s): R. Wang, B.-Z. Wang, X. Ding, C. Hu
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 1950 KB

Title: A Comparative Study of Opposition-Based Differential Evolution and Meta-Particle Swarm Optimization on Reconstruction of Three Dimensional Conducting Scatterers
Abstract: In this paper, opposition-based differential evolution and Meta-particle swarm optimization is applied to reconstruct three dimensional conducting scatterers. Rational Bezier surfaces are utilized to model the shape of the scatterers. The mathematical representation of this surfaces are expanded in terms of Bernstein polynomials. The unknown coefficients of these polynomials depend on a few control points in space. An optimization method is used to find the location of the control points such that a specific measure of the difference between radar cross section (RCS) of the reconstructed and the original target is minimized. Physical optics (PO) approximation is used to find the RCS of a reconstructed scatterer in each iteration of the proposed algorithm. Simulation results show that these algorithms are very stable in the presence of noise.
Author(s): M. Maddahali, A. Tavakoli, M. Dehmollaian
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 1676 KB

Title: 3-D Defect Profile Reconstruction from Magnetic Flux Leakage Signals in Pipeline Inspection Using a Hybrid Inversion Method
Abstract: In this paper, we propose a hybrid inversion approach to reconstruct the profile of arbitrary threedimensional (3-D) defect from magnetic flux leakage (MFL) signals in pipeline inspection. The region of pipe wall immediately around the defect is represented by an array of partial cylinder cells, and a reduced forward FE model is developed to predict MFL signals for any given defect. The neural network (NN) method is used at first to give a coarse prediction of the defect profile, and the prediction is then utilized as one original solution of the genetic algorithm (GA) to search for the global optimum estimate of the defect profile. To demonstrate the accuracy and efficiency of the proposed inversion technique, we reconstruct defects from both simulated and experimental MFL signals. In both cases, reconstruction results indicate that the hybrid inversion method is rather effective in view of both efficiency and accuracy.
Author(s): J. Chen
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 1913 KB

Title: Optimal Design of Elliptical Array Antenna Using Opposition Based Differential Evolution Technique
Abstract: Radiation pattern synthesis of non-uniformly excited planar arrays with the lowest relative side lobe level (SLL) is presented in this paper. Opposition based differential evolution (ODE) scheme, which represents a novel parameter optimization technique in antenna engineering is applied for the parameter optimization of the single and the multi-ring circular array (CA), hexagonal array (HA) and elliptical array (EA) of isotropic elements. To overcome the problem of premature convergence of differential evolution (DE) algorithm, ODE is designed without significantly impairing the fast converging property of DE. Two design examples are presented which illustrate the effectiveness of the ODE based method, and the optimization goal for each example is easily achieved. The design results obtained using ODE are much more improved than those of the results obtained using the state of the art evolution algorithms like particle swarm optimization (PSO), harmonic search (HS) and differential evolution (DE) methods in a statistically significant way.
Author(s): R. Bera, D. Mandal, R. Kar, S. P. Ghoshal
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
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Title: On the Theoretical Analysis of Radiation Pattern and Gain of Printed Monopole Antennas
Abstract: This paper reports a theoretical approach to analyze radiation pattern and gain of Printed Monopole Antennas (PMA). Theoretical analysis of PMAs is performed by modeling PMA as an asymmetrical dipole antenna. The effect of patch and ground plane is considered separately then combined. The far field expressions for rectangular and circular PMAs are derived and verified with available experimental results from published work and High Frequency Structure Simulator (HFSS) simulated results. The analytical, simulated and available measured results are in close agreement. The theoretical gain for rectangular and circular monopole antennas are also computed and compared with HFSS simulation results.
Author(s): S. Bhattacharjee, R. S. Kshetrimayum, R. Bhattacharjee
File Type: Journal Paper
Issue:Volume: 32      Number: 9      Year: 2017
Download Link:Click here to download PDF     File Size: 1683 KB