ACES Publication Search
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| Title: | ACES Journal April 2020 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 2238 KB |
| Title: | ACES Journal April 2020 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1358 KB |
| Title: | ACES Journal April 2020 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 14816 KB |
| Title: | An FDTD TF-SF Boundary on Face-Centered Cubic Grids |
| Abstract: | The implementation of total-field/scatteredfield (TF-SF) boundary for finite-difference timedomain (FDTD) method was proposed based on facecentered cubic (FCC) grids. On the basis of the arrangement of fields components in the FCC voxel, the update equations for the electric and magnetic field components of the TF-SF boundary are derived. The resonant frequency of a cavity is calculated to illustrate that the FCC grid scheme is more accurate as compared to the equivalent Yee grid method. Then, by simulating the amplitude distribution of the vertical and oblique incident plane waves in the whole calculation region, the effectiveness of the TF-SF boundary is verified numerically. |
| Author(s): | L. Shi, L. Yang, W. Feng |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1805 KB |
| Title: | Benchmark Electromagnetic Inverse Scattering by Using Differential Evolution – A Big Data Perspective |
| Abstract: | The benchmark electromagnetic inverse scattering problem is re-visited in this paper from a big data perspective. It serves as the benchmark application problem in systematic parametric study of differential evolution (DE). Representative strategies with a full sweeping of intrinsic control parameters are applied to draw a systematic picture of DE. Insights extracted from preliminary numerical results are presented to rebut the questionable statements and advise DE applicants. |
| Author(s): | A. Qing |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1643 KB |
| Title: | Application of PS-ADI-MRTD Method in Frequency Selective Surface Analysis |
| Abstract: | In this paper, a novel periodic spectral alternating direction implicit multi-resolution time domain (PS-ADI-MRTD) method is proposed for solving periodic structures. The algorithm for inversion of the block periodic tri-diagonal matrices is presented. A typical example is given to validate the effectiveness of the proposed algorithm, and the numerical results also show that the proposed algorithm can save more computation time than the traditional MRTD method. Furthermore, the PS-ADI-MRTD method is applied to analyze the electromagnetic scattering characteristics of two types frequency selective surface (FSS) structures. |
| Author(s): | Y. Liu, P. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1305 KB |
| Title: | Robust Optimization of Electromagnetic Design Using Stochastic Collocation Method |
| Abstract: | The way to handle the uncertainty of design parameters has attracted wide attention in the optimization of electromagnetic designs. The Monte Carlo Method works well when dealing with uncertainties but it consumes too much time and computational resources. This paper proposes a computationally efficient way to achieve robust optimization based on Stochastic Collocation Method and the TEAM 22 problem is used as a verification example. It is demonstrated that the approach combining Stochastic Collocation Method and a genetic algorithm provides high computational efficiency, without losing accuracy compared with the Monte Carlo Method. |
| Author(s): | G. Zhang, R. Zhu, J. Bai, X. Peng |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1517 KB |
| Title: | Numerical Simulation and Experimental Study of ISAR Imaging of Spherical Convergent Flap Nozzle |
| Abstract: | The research on the electromagnetic scattering characteristics of the aero-engine nozzle can provide an important reference for the electromagnetic stealth design of aircraft. In this paper, the numerical simulation and experimental measurement are used to study the radar cross section (RCS) and inverse synthetic aperture radar (ISAR) image characteristics of spherical convergence flap nozzle (SCFN). Firstly, the feasibility of using the shooting bouncing ray (SBR) method to calculate the scattering characteristics of electrically large and deep cavity is verified. Secondly, the numerical simulation data and experimental data of electromagnetic scattering of SCFN are processed by ISAR imaging algorithm, the numerical and experimental ISAR images of SCFN are obtained. The results show that SBR can effectively calculate the RCS of the electrically large size cavity within ± 30° of the axis direction. The polarization influences the experimental ISAR image. Both the numerical and the experimental ISAR image can accurately reflect the scattering center distribution inside the SCFN, and the numerical ISAR image is superior to the experimental ISAR image in image entropy and equivalent number of looks (ENL), and is partly inferior to the experimental ISAR image in terms of image average gradient. The results prove the validity and accuracy of the numerical ISAR image. |
| Author(s): | Y. Liang, Q. Yang, Y. Shi, J. Bai, Q. Lin |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1877 KB |
| Title: | A Source Signal Recovery Method for Underdetermined Blind Source Separation based on Shortest Path |
| Abstract: | A new shortest path source recovery algorithm is presented for source signal recovery issue in underdetermined blind source separation, by which the source signals can be recovered in case the observed signals are no less than two dimensions. In this algorithm, two adjacent observed signals are taken everytime among m observed signals, marked as the ith and jth signals, and form a two-dimensional observed signal combination, i=1,2,...,m-1,j= i+1 . The first and mth signals are used to form another twodimensional observed signal combination, then m twodimensional observed signal combinations are obtained. The number of source signals is n, the n signals can be obtained respectively after signal recovery by using each two-dimensional observed signal combination A matrix (i.e., s(p,q,:)=[sˆ(1,1,:), sˆ(1,2,:),..., sˆ(1,n,:), sˆ(2,1,:),... , sˆ(m,n,:)T]) which is a mn-dimensional vector combination matrix can be obtained using each signal combination A mnmn-dimensional square matrix can be gotten by calculating the vector angle between rows of s(p,q,:) matrix, for the first n rowsmn columns, position the vector where the matrix elements are between 0 and θ0. The mean is calculated for the signal vector with angle smaller than θ0 as the estimate of the source signals. Thus, the estimates sˆ(1,:), sˆ(2,:),..., sˆ(n,:) of n source signals can be obtained eventually. The method presented provides a new option for solving underdetermined blind source signal recovery problem. |
| Author(s): | C. Wang, R. Jia |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1434 KB |
| Title: | Position Deviation Evaluation for UAV Inspecting Overhead Transmission Line Based on Measured Electric Field |
| Abstract: | Unmanned aerial vehicle (UAV) used in overhead transmission lines (OTLs) inspection are required to fly along a preset path to conduct special tasks. However, UAVs sometimes deviate from the preset path due to positioning error or control error in practice, thereby reducing the quality of the inspection task or even leading to serious line collision accidents. In this study, a method is proposed to evaluate the UAV position deviation from the preset path in real time on the basis of a measurement and analysis on the electric field generated by transmission lines. A new idea is presented to solve the obstacle avoidance problem for UAV in transmission line inspection. To improve evaluation accuracy, the influences of transmission tower and UAV body are considered in the theoretical calculation model for electric field, and the electric field data are preprocessed to diminish the influence of environmental noise and measurement inherent error. To improve the real-time performance of the evaluation algorithm, the dynamic programming and hidden Markov model (HMM) are combined to form a dynamic-hidden Markov model algorithm, in which the parameters of the HMM are determined by the expected maximization parameter estimation and corrected in real time. The feasibility and accuracy of the proposed method are verified by several simulation examples and experiments. |
| Author(s): | D. Xiao, Q. Zheng, J. Lei, S. Liu |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1707 KB |
| Title: | Electromagnetic Radiation Driven Phase Transition in Silver Telluride-Iron Oxide and Iron Telluride Nano-Composites |
| Abstract: | Temperature-dependent switchability of electrical property has drawn a lot of attention recently. In this article, electromagnetic (EM) radiation is used to induce temperature change in silver telluride and iron telluride nanostructures, which can be potentially used to trigger electrical property changes in them. Due to the low EM absorptivity of silver telluride nanowire, heating it via EM fields is very challenging. To enhance its EM absorptivity, various percentages (by mass) of iron oxide powder are mixed into it. It is verified that, similar to pure silver telluride, the mixture also exhibits a rapid change in electrical conductivity within a certain temperature range. The experiment is designed to characterize the EM absorptivity of three such mixtures with different percentage compositions and an iron telluride nanodisk in the X-band frequency range (8 to 12 GHz). The temperature increase induced by the absorbed EM energy will lead to the rapid change of electrical conductivity by α-type to β-type phase transition in silver telluride and p-type to n-type transition in iron telluride, which can be potentially used to develop EM sensors for applications in communication technology. |
| Author(s): | Y. Bao, W. Zheng, P. Gurrala, B. Xu, J. Song, Y. Wu |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1537 KB |
| Title: | Adaptive Sparse Array Beamforming Using Correntropy Induced Metric Constrained Normalized LMS Algorithm |
| Abstract: | In order to further exploit the sparseness of antenna array and speed up the convergence of constrained normalized LMS (CNLMS) algorithm, maintaining good beam pattern performance and better output signal-to-interferences-plus-noise ratio (SINR), a new method with approximation l0-norm constraint is proposed to improve CNLMS algorithm, and its derivation process is given in detail. In this newly proposed algorithm, the correntropy induced metric (CIM) is used to approximate the l0-norm, which is considered construct a new cost function to fully exploit the sparsity of the antenna array and reduced the number of active array elements. Using the CIM penalty, the proposed CIM-based CNLMS (CIM-CNLMS) algorithm is derived in detail, where the Lagrange multiplier method is utilized to solve the cost function of the proposed CIM-CNLMS algorithm, and the steepest descent principle is considered to obtain the update equation. The computer simulation results demonstrate that compared with other CLMS algorithms, the new algorithm obtains better performance, which greatly reduces the proportion of active array elements in the thinned antenna array. Simultaneously, the new algorithm has excellent beam pattern performance and better SINR performance with faster convergence speed and more stable mean square error. |
| Author(s): | Z. Dai, L. Guo, J. Yin, Y. Li, K. Guo |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1642 KB |
| Title: | Efficient Indoor Signal Propagation Model Based on LOLA-Voronoi Adaptive Meshing |
| Abstract: | An innovative adaptive mesh strategy based on LOLA-Voronoi (Local Linear Approximation-Voronoi) is proposed to efficiently predict indoor signal propagation. This indoor high-efficiency propagation model (HPMO) can identify nonlinear regions to capture the complex behavior and achieve sufficient prediction accuracy when the computational cost is limited. A set of representative reference scenario simulation settings and results are reported and discussed to analyze the accuracy, and the efficiency of HPMO. Comparison with the original model based on traditional uniform mesh shows that the proposed method herein yields a considerable reduction in the prediction calculation cost of the complex indoor environment, while maintaining sufficient accuracy. |
| Author(s): | J. Yao, W. Tang, B. Li, S. Zhang, R. Sun |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1678 KB |
| Title: | Dual Band, Miniaturized, Implantable Antenna Design with On-body Antennas for Wireless Health Monitoring |
| Abstract: | A modified Hilbert fractal geometry and serpentine radiator-based implant antenna is proposed for dual band medical operations in both the MICS band (402-405 MHz) and ISM band (2.4–2.48 GHz). The antenna has miniaturized dimensions of 5.5 x 7.6 x 0.8 mm3 (width x height x thickness) and is simulated inside a four layer (air, skin, fat and muscle) model with dimensions of 150 mm x 75mm x 55 mm. A Zirconia (ɛr=29) superstrate and shorting pin were utilized to achieve biocompatibility and the desired resonance. Relatively stable and omni-directional radiation patterns were achieved for the dual band operation. An ISM band on-body antenna (5.8 x 5.5 x 0.8 mm3) was proposed to generate a wake-up signal while the wireless telemetry transmission was achieved using the MICS band on-body antenna (5.8 x 5.5 x 0.8 mm3). Implant and on-body antennas demonstrated a reflection coefficient (S11) better than -10 dB characteristics. To adhere to the SAR regulation limit of 1.6W/kg, the peak incident power should not exceed 0.25 mW and 0.2 mW for the ISM band and MISC band on-body antennas respectively. Propagation channel characteristics were simulated by observing the S12 and S13 characteristics and satisfactory results were achieved. The peak gain for the implant, MICS band and ISM band on-body antennas were -39.8 dBi, -35.6 dBi and -23 dBi, respectively due to the miniature dimensions. The miniaturized characteristics, dual-band operation, biocompatibility and stable characteristics in the presence of human tissue model make both the implant and on-body antennas suitable for biomedical monitoring systems. |
| Author(s): | A. O. Kaka, M. Toycan, S. D. Walker, D. Kavaz |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 2375 KB |
| Title: | Design and Simulation of 77GHz Substrate Integrated Waveguide Slot Array Antenna |
| Abstract: | In this paper, a 77GHz slot array antenna for millimeter-wave automotive radar application is designed and simulated using HFSS, in which the substrate integrated waveguide (SIW) is adopted. First, a linear array with 16 slots is designed, and its parameters are achieved by extracting the characteristics of the radiating slot in the array environment and comparing them with the array synthesis result. Then, a tree-shaped unequal feeding network with improved vertical transition is presented to make the entire array more compact. Finally, the configuration of the designed 8 × 16 planar array antenna is given, and the fabrication error is analyzed. The simulation results of the 77GHz SIW slot array antenna show that its sidelobe levels (SLLs) are below -25dB in the E-plane and below -27dB in the H-plane, and the corresponding half-power beamwidths are 13.9° and 9.7°, respectively. |
| Author(s): | B.-Y. Guo, H. Jiang |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1669 KB |
| Title: | A Multiply Parasitic-Coupled, Three-Dimensional Antenna Array with Wide Elevation Angle for Seamless UAV Communications |
| Abstract: | A multiply parasitic-coupled, three-dimensional antenna array with wide elevation angle for seamless unmanned aerial vehicle (UAV) communications is proposed. The proposed array consists of an upper substrate with a two-element dipole array, multiple parasitic elements, two supports including a microstrip feeding, and a lower substrate with a feeding network and its ground plane as a metallic reflector for wide radiation pattern and reduced back radiation. The proposed array operates with a 18% impedance bandwidth ranging from 4.51 GHz to 5.43 GHz by covering an UAV communications frequency band. Measured peak gain, total efficiency, and half-power beamwidth (HPBW) of the proposed array are approximately 5.5 dBi, 95%, and 140°, respectively. |
| Author(s): | D.-G. Seo, W.-S. Lee |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1833 KB |
| Title: | Compact Substrate Integrated Waveguide Band-pass Rat-race Couplers Based on Mixed Shape Cavity with Flexible Port Topology |
| Abstract: | A new type of compact band-pass rat-race couplers with flexible port topology based on mixed shape substrate integrated waveguide (SIW) cavity is first proposed in this paper. Moreover, composite right/left-handed (CRLH) SIW unit loaded on the common wall between cavities is used to achieve negative coupling structure. The diameter of the vias on the common wall related CRLH-SIW unit is also used to adjust the electric coupling strength and increase the coupling bandwidth. The detailed analysis and the design method have been introduced to realize a filtering rat-race coupler based on substrate integrated fan-shaped cavity (SIFC) and rectangular cavity (SIRC). In particular, the combination of mixed shape resonators and port location in rectangular resonators can be selected according to the requirement of port angle interval. Compared with other filtering couplers, the proposed designs exhibit good filtering responses, high Q factor, better isolation, multiple port angle intervals, amplitude balance, as well as 0° and 180° phase differences. |
| Author(s): | Z. Zhang, Y. Fan, Y. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 2511 KB |
| Title: | Compact-Size Bandpass Filter for S-Band Transceivers of LEO Satellites |
| Abstract: | This paper introduces a variety of designs for low-cost and compact-size bandpass filter (BPF) proposed for S-band space-links between ground stations and low earth orbit (LEO) satellites. The proposed designs implement multiple cascaded coplanar waveguide (CPW) resonators with either single or double resonance. The first design is a compact dual-band BPF of dimensions 13×11 mm2 that can operate simultaneously for both the uplink and downlink in an S-band transceiver. The second design is a single-band BPF of dimensions 25×10 mm2 that can operate for the space uplink. The third design is a compact single-band BPF of dimensions 17×12 mm2 that can operate for the space downlink. The three designs are compact size, low cost, and high performance BPFs. The dual-band BPF design is based on dual-resonance mechanism where the resonant structure is constructed as two overlapped quarter-wavelength and half-wavelength CPW resonators; each of them operates in its first-order resonance. The single-band design is based on a quarter-wavelength CPW resonator. Three prototypes are fabricated for the proposed filter designs and their frequency responses are assessed through simulation and experimental measurements showing good agreement. It is shown that the implemented designs satisfy the operational requirements for the assigned space link with high performance, good impedance matching, and low insertion loss. |
| Author(s): | A. E. Farahat, K. F. A. Hussein |
| File Type: | Journal Paper |
| Issue: | Volume: 35 Number: 4 Year: 2020 |
| Download Link: | Click here to download PDF File Size: 1939 KB |