ACES Publication Search
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| Title: | ACES Journal November 2019 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2209 KB |
| Title: | ACES Journal November 2019 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 815 KB |
| Title: | ACES Journal November 2019 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 21069 KB |
| Title: | FDTD Modeling of Coils for Wireless Charging Applications |
| Abstract: | Wireless power transfer using inductive/ resonant coupling is studied using the finite-difference time-domain (FDTD) method. Three-dimensional FDTD models are used to simulate the source and load loops as well as frequency-dependent magnetized ferrite shields. A series of tests are run to determine the required distance between the coils and the domain edges, the PML thickness, and convergence level. The FDTDcalculated coil parameters (self-inductance and quality factor) are then validated against measurement results. The efficiency of the inductive link is studied without ferrite shields and then with two ferrite slabs added. It is observed that adding ferrite slabs improves the efficiency by ~40%. |
| Author(s): | S. Pokhrel, G. Moss, J. J. Simpson |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1579 KB |
| Title: | Application of Barycentric Subdivision Method for Singularity Integration in Method of Moments |
| Abstract: | Method of moments (MoM) is an essential tool to model electromagnetic wave interactions with three-dimensional targets. Numerical integration is a key technique in MoM. Due to the singular nature of Green's function, MoM requires special treatment in the calculation of singular integration, which is usually timeconsuming. In this study, the barycentric subdivision method is investigated to compute numerical integration in three-dimensional surface integral equations. This method allows a uniform treatment for both singular and non-singular integrals. Numerical examples show that this method could reach the same level of accuracy as the singularity extraction method for RWG basis functions, and the computational time of setting up the matrix can be reduced by half. |
| Author(s): | C. Xiang, X. Dang, M. Li, F. Yang, S. Xu |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1766 KB |
| Title: | Propagating and Scattering of the Electromagnetic Vortex Generated by a Spiral Parabolic Antenna |
| Abstract: | A modified octree grouping scheme of the multilevel fast multipole algorithm (MLFMA) is proposed to analyze the electromagnetic (EM) scattering from the electrically large target, which is illuminated by a spiral parabolic antenna. The spiral parabolic antenna is used to generate the electromagnetic vortex of a specific mode number by adjusting the height of split. The proposed method builds two octree groups and decouples the interaction between the antenna and the target, so as to save the computational resource and improve the computational efficiency. Using this scheme, the numerical example with double metal spheres illuminated by the electromagnetic vortex reveals some special phenomena due to the spiral phase distribution, while the example with a scaled-down airplane at long operating range demonstrates that the electromagnetic vortex tends to be plane wave locally with the increase of propagation distance. |
| Author(s): | B. H. Yin, Z. He, R. S. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1572 KB |
| Title: | Fan-Type AMC Surface for Broadband Low-RCS Applications |
| Abstract: | An artificial magnetic conductor (AMC) surface is proposed in this paper to reduce radar cross section (RCS) by more than 10 dB in a broad frequency band. The proposed AMC structure consists of two different units - seven hexagonal circles and Jerusalem cross loaded with four L-type branches, contributing to a wide phase difference (180°±37°) frequency band. To obtain a low RCS value, the two proposed units are arranged in fan-type for the AMC surface. The simulated results show that the RCS can be reduced by more than 10 dB in a broad frequency band from 12.2 to 27 GHz (75.5%). The proposed AMC structure combined by 20×20-unit cells is fabricated and measured in anechoic chamber. Measured results in the band below 18 GHz of the fabricated prototype agree well with the simulated ones, which validates that the proposed AMC surface may be utilized on low-RCS platforms. |
| Author(s): | X. Song, L. Chen, Z. Yan, Y. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1716 KB |
| Title: | Full and Independent Manipulation of Co- and Cross-polarized Waves with Metasurface |
| Abstract: | A novel metasurface based on the amplitudephase manipulation and beamforming is proposed for the control of co- and cross-polarized wave simultaneously and independently. The metasurface consists of two polarization conversion elements (PCEs) and their mirrors: the two PCEs are used to control the co-polarized waves with the co-polarized field component of equal amplitude and opposite phase, and the mirrors of them that are intent to control the cross-polarized waves. Full manipulation of the amplitude and phase for both coand cross-polarized components of the reflected waves is realized by adjusting the geometric parameters of two PCEs. Compared with the traditional co-polarized phaseonly manipulation, freedom degree of manipulation is increased from 1 to 4, which greatly increases the ability of manipulating electromagnetic waves. The arrangement of PCEs is obtained based on the planar array theory to achieve the desired co-polarized and cross-polarized scattering patterns. The theoretical analysis, simulation and experiment results are in good agreement and verify the proposed mechanism. |
| Author(s): | J. Su, J. Liu, Z. Li, L. Y. Yang |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2126 KB |
| Title: | An Effective Iterative Algorithm to Correct the Probe Positioning Errors in a Non-Redundant Plane-Rectangular Near-Field to Far-Field Transformation |
| Abstract: | An algorithm for the effective compensation of known positioning errors, affecting the samples acquired by the probe in a non-redundant plane-rectangular (PR) near-field to far-field (NFFF) transformation, is presented and fully assessed by experimental tests. This transformation adopts a non-conventional PR scan, named planar wide-mesh scan (PWMS), characterized by meshes widening more and more as their distance from the measurement plane center increases, and uses a nonredundant sampling representation of the probe voltage. Such a representation is obtained by considering the antenna as contained in an oblate spheroid, to precisely determine the input NF data for the traditional PR NFFF transformation from the PWMS samples. These samples are unavailable in presence of positioning errors, but, as it will be shown, can be effectively retrieved from the errors affected ones by applying an iterative procedure. |
| Author(s): | F. D’Agostino, F. Ferrara, C. Gennarelli, R. Guerriero, M. Migliozzi |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1822 KB |
| Title: | A Novel Finite Element Mesh Truncation Technology Accelerated by Parallel Multilevel Fast Multipole Algorithm and its Applications |
| Abstract: | In order to meet the highly accurate requirements of nowadays scattering and antenna problems, the finite element method requires the use of very accurate mesh truncations techniques able to absorb any outgoing wave completely. In this paper a novel implementation of the finite element mesh truncation technique called Finite Element-Iterative Integral Equation Evaluation (FE-IIEE) is studied. This method can provide a numerical exact radiation boundary condition while the original sparse and banded structure of the finite element method (FEM) matrix is retained. Also, an efficient parallel multilevel fast multipole algorithm (MLFMA) is included to drastically accelerate the time-consuming near field calculation process required by the truncation technique. In order to achieve a high parallel efficiency, both algorithms have been implemented together from scratch, being able to run over several thousands of CPU cores. Through comparisons with commercial software such as HFSS, the accuracy and efficiency of the method are validated showing excellent performance. Finally, a large 100- elements array antenna with more than 24 million unknowns is effectively analyzed using 2560 CPU cores. |
| Author(s): | S. Zuo, Y. Zhang, D. G. Donoro, X. Zhao, Q. Liu |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2048 KB |
| Title: | Broadband Tracking of Characteristic Modes |
| Abstract: | Effective mode sorting is the key to achieving characteristic mode (CM) analysis for open conductors. However, mode ordering just according to the eigenvalue magnitude may cause the mode crossing in the operating band. Mode tracking must be performed to obtain the correct mode ordering. Currently, mode tracking based on eigenvector correlation is usually only applicable to narrowband cases due to the large interval between the sampling frequency point and the first frequency. In this paper, the correlation calculation is directly performed between two adjacent frequencies, and the first frequency is not used as the anchor point. Due to the improvement of the eigenvector correlation, the broadband mode tracking is realized. Some numerical examples are used to verify the effectiveness of this algorithm. |
| Author(s): | J. Zhu, W. Li, L. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1585 KB |
| Title: | The Application of Chirp Z-Transform in Fast Computation of Antenna Array Pattern |
| Abstract: | As an essential means of evaluating antenna array performance and the basis of antenna array design, numerical computation of antenna array pattern is very important. Computation of antenna array pattern by using straightforward summation is very time consuming especially for planar array with many elements. Moreover, in some applications such as antenna array synthesis, huge number of repeated pattern computations is needed that the consumed time is intolerably long. Although the computation can be accelerated by fast Fourier transform (FFT) when the elements are equally spaced by half of a wavelength because the array factor and the element excitation currents is a Fourier transform pair, in general, FFT is not applicable. In this paper, the chirp z-transform (CZT) is introduced to accurately and efficiently compute pattern of general linear or planar antenna arrays. Numerical examples confirm that CZT is flexible, efficient, and accurate. |
| Author(s): | C. Zhang, A. Qing, Y. Meng |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1910 KB |
| Title: | X-Band Isoflux Concentric Circular Antenna Arrays for Image Data Download from LEO Satellites to Ground Stations |
| Abstract: | A circularly polarized isoflux beam synthesized by concentric circular arrays of printed microstrip patch antennas is proposed for X-band transmission of image data from land-imaging LEO satellites to the ground stations. This beam has a wide coverage angle of about 100° of uniform illumination. The paper introduces a novel design of a compact righthand circularly polarized microstrip patch as an element for the concentric circular arrays. The patch antenna has impedance matching bandwidth of about 600 MHz and axial ratio bandwidth of about 170 MHz at 8.1 GHz. A prototype of the proposed patch antenna is fabricated for experimental measurements. The electromagnetic simulation and experimental results show good agreement. A computationally efficient particle swarm optimization (PSO) procedure is developed and applied to find the distribution of the excitation magnitudes over the array elements so as to generate an isoflux beam in all the elevation planes with circular symmetry in the azimuth planes. The phase of excitation is the same for all the array elements. The method proposed to apply the PSO reduces the computational resources to about 6.5% of those required by the conventional method of application. Moreover, the proposed iterative PSO procedure is shown to be very fast convergent. |
| Author(s): | M. A. El-Hassan, K. F. A. Hussein, A. E. Farahat, K. H. Awadalla |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1802 KB |
| Title: | Single Layer Transmit-array with Beam-Steering and Polarization Switching |
| Abstract: | In this paper, a single layer multipolarization transmit-array operating at C-Band is designed using ring groove with a single split as the element. The rotational orientation of each element can provide the required phase shift. The elements have identical dimensions, but the rotational orientation of each element is selected to provide a specific transmitarray function. The transmit-array has three working conditions which can change the polarization of the incident wave and set separation beam direction at the same time. The thin single-layer transmit-array without dielectric substrate is designed, simulated and measured based on a horn antenna. The measurement result shows that the transmit-array can switch the linear polarization incident wave to left-circularly polarized wave and righthanded circular polarized wave with separation beam of ± 30 azimuth angles separately. The measured results are in agreement with the theoretical and simulation results. |
| Author(s): | X. Liu, Q. Yu, X. Kong, Z. Huang, B. Bian, S. Liu, J. Liu |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1867 KB |
| Title: | A W-Band Dual-Polarization Slot Array Antenna with Low Sidelobe Level |
| Abstract: | A 94-GHz dual-polarization low-sidelobelevel slot array antenna is proposed. A 2x2-slot cavitybacked subarray is adopted as the basic unit of the array. A high-isolation orthogonal-mode transducer (OMT) with a simple structure is used to excite the dualpolarization subarray. The realization of a low sidelobe level depends on the amplitude-weighted waveguide feed network. A novel unequal power dividing ratio but equal phase (UPEP) single-ridged waveguide divider is presented for the construction of the vertical polarization (VP) array feed network. A 16x16-slot low-sidelobelevel dual-polarization array antenna is fabricated. The machining difficulties of the W-band array are reduced by using simpler structures. The measured results show that the impedance bandwidth is greater than 7.3 GHz, while the first sidelobe levels are lower than -20.1 dB for both polarization arrays within the operating bandwidth. The measured gain is higher than 30.9 dBi for the two polarization arrays with an antenna efficiency better than 64%. |
| Author(s): | H. Luo, Y. Xiao, W. Tan, L. Gan, H. Sun |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2036 KB |
| Title: | Broad-Band I-Shaped SIW Slot Antenna for V-Band Applications |
| Abstract: | In this article, the broad-band SIW slot antenna is proposed for V-band applications, I shaped slot is used in this design and useful for millimeter-wave communication applications. The material used in this design is RT-Duriod 5880 with ε2=2.2 with a thickness of 0.381mm and copper thickness is 35um. The proposed antenna is designed, simulated, printed and tested. The antenna has an impedance bandwidth of 5.1GHz ranges from 57GHz to 62.1GHz and discusses the parameters like VSWR, radiation patterns, gain. The antenna has validated with comparison of simulation and measured results. |
| Author(s): | M. Nandakumar, T. Shanmugnantham |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1752 KB |
| Title: | A Bowtie Slotted Quad-Band Notched UWB Antenna with Defected Ground Structure |
| Abstract: | A novel compact bowtie slotted circular patch antenna with quad-band notched characteristics is demonstrated in this work. The presented prototype is ascertained on FR-4 substrate. Initially, an Ultra- Wideband (3.1-10.6 GHz) antenna is achieved. Later, undesirable bands between 3.55-5.16, 5.52-5.73, 6.44- 6.78 and 7.61-10.6 GHz are eliminated by incorporating slots in the patch. By proper optimization of the patch as well as ground plane, four resonant bands are achieved between 2.56-3.53, 5.22-5.5, 5.7-6.4 and 6.81-7.53 GHz supporting LTE2500, WiMAX, WLAN, and X-band applications. For good impedance matching, the antenna employs a very unique bat-shaped defected ground plane structure. The peak gain of 3.7 dB is obtained by the proposed radiator. A good agreement is observed between the measured and simulated results. |
| Author(s): | A. Javed, S. I. Naqvi, F. Arshad, Y. Amin, H. Tenhunen |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1616 KB |
| Title: | A Compact Dual-band MIMO Antenna for 5G Mobile Communications |
| Abstract: | In this paper we propose a compact dualband MIMO antenna for 5G mobile communications. Its element is a dual-band monopole working at 3.4 GHz and 4.9 GHz. In order to cover the commercial 5G communication band of sub-6 GHz (3.3-3.6 GHz and 4.8-5.0 GHz), an inverted L-shaped strip is added on the ground of the monopole to achieve a band-notch of S11 at 3.4 GHz and a quasi-directional radiation pattern. The proposed MIMO antenna has a compact size of 50*50*0.8mm3 and it’s composed of four improved monopoles mentioned above with mutually orthogonal placement. Long strips are loaded on the ground layer and antenna layer to obtain a better port isolation at 3.3- 3.6 GHz. The measured results show that the reflection coefficient (Sii) of the MIMO antenna is less than -10 dB at the lower band and less than -20dB at the higher band. Its -10dB-bandwidth covers the band of 3.3-5.8 GHz and the mutual coupling (Sij) between ports keeps lower than -20dB within the dual-band. The envelope correlation coefficients (ECC) of the MIMO antenna are also measured and they’re below 0.01. A channel model is used to calculate the MIMO channel capacity and the results show this MIMO channel performs best at 5 GHz. |
| Author(s): | J. Su, Z. Dai, J. Du, J. Yu, Z. Chen, Z. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1974 KB |
| Title: | Anti-Jamming Front-End Design of Satellite Navigation Receiver |
| Abstract: | In this paper, an anti-jamming front-end is proposed for the satellite navigation receiver. Firstly, a seven-element receiving antenna array and an eightchannel (seven receiving channels and one calibration channel) radio frequency (RF) module are devised. Then, the interference suppression module based on the linear constraint minimum variance (LCMV) criterion are designed and analyzed. By using the LCMV-PI algorithm, the spatial domain information of the signal can be used to effectively suppress the interference. In addition, considering that the channel inconsistency will adversely affect the interference suppression algorithm and subsequent signal acquisition and tracking, a channel equalization scheme is devised to correct the channel inconsistency. |
| Author(s): | F. Wang, H. Liu, C. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1925 KB |
| Title: | Improved Gaussian Process Modelling of On-Axis and Off-Axis Monostatic RCS Magnitude Responses of Shoulder-Launched Missiles |
| Abstract: | An improved Gaussian-process-based technique is described for modelling both on-axis and off-axis monostatic RCS magnitude responses of shoulder-launched missiles. The RCS responses are complicated, oscillatory, quasi-periodic functions of frequency, with the oscillation periods being related to the spacings of the scatterers comprising the missiles. The updated modelling approach employs a spectralmixture covariance function, whose components explicitly include distinct oscillations. The proposed technique is evaluated by means of two example missiles. For the six rotations considered, average predictive normalised RMSE ranged from 0.34% to 0.87% and from 0.95% to 1.53% for the two missiles respectively. |
| Author(s): | W. P. du Plessis, J. P. Jacobs |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1840 KB |
| Title: | An Analytical Approach for a Miniaturized Unequal Wilkinson Power Divider with Filtering Response |
| Abstract: | In this paper, a closed-form design method for a novel compact unequal filtering Wilkinson power divider, WPD, based on symmetric and asymmetric right/left-handed (CRLH) coupled-line circuit structures is proposed and investigated. The structure is composed of an input asymmetric CRLH coupled-line (A-CRLH) section along with two output symmetric CRLH coupled-line band-pass filter transformers to provide unequal filtering performance. The analytical design equations along with ideal closed-form expressions for scattering parameters are derived for the proposed structure by using in- and anti-phase (c/π-mode) decomposition method. To theoretically verify the proposed design approach, two filtering unequal WPDs with different high-power dividing ratios of 1:10 and 1:15 are designed and simulated. Finally, as a typical example, a practical filtering WPD with a power-splitting ratio of 1:15 operating at 1.4 GHz, is implemented with more than 55.5% size reduction as compared to conventional one. Good agreement between calculated, simulated and measured results verifies the effectiveness of the proposed power divider for miniaturized, large power dividing ratio and filtering applications. |
| Author(s): | Y. Torabi, G. Dadashzadeh |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1733 KB |
| Title: | Active Inductor Design for Reconfigurable Bandpass Microstrip Filter Applications |
| Abstract: | Herein, the design of an active inductor and its typical application for a reconfigurable band-pass filter circuit are presented. The Active Inductor design consists of a passive variable phase and amplitude compensating network and a highly linear inverting amplifier in order to form a gyrator-C design. The design allows a wide frequency range for tuning the equivalent inductance and resistance values that enable it to be used as a filter design where the inductor equivalent resistance increases and improves signal rejection for band-pass filter applications. As a typical application, first-order active band-pass filter had been designed and prototyped. The simulation and measurement results of the design are compared with the performance results of counterpart designs in literature. From the experimental results, it can be concluded that the proposed design is a suitable model for design of tunable band pass filter circuits. The design has an operation band of 0.7-2.1GHz with the equivalent inductance value of 2.6nH. |
| Author(s): | M. A. Belen, P. Mahouti |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1514 KB |
| Title: | Analysis of Lossy Multiconductor Transmission Lines (MTL) Using Adaptive Cross Approximation (ACA) |
| Abstract: | In this article, an efficient adaptive cross approximation (ACA) algorithm is employed for the lossy of MTL such as propagation matrix, attenuation loss, dielectric loss and characteristic impedance are evaluated. ACA solver is stable and convenient to solve the compression and approximation of low-rank matrix because adaptive refinement is used to generate the optimal mesh. The integral equation (IE) solver along with adaptive cross approximation (ACA) is used to reduce the computational time and memory size. In the proposed algorithm, the complexities become linear. Therefore, the ACA provides less memory size and less computation cost. The results are compared with the latest state of the art existing work for validation. |
| Author(s): | A. Mueed, Y. Zhao, Y. Wei, Z. B. Zhu, Q. L. Liu |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1745 KB |
| Title: | Rotary Coupling Magnetic Field Characteristics of a Two-Degree-of-Freedom Direct Drive Induction Motor |
| Abstract: | A two-degree-of-freedom direct drive induction motor is investigated in this study. Owing to its special structure and motion forms, coupling magnetic fields are generated inside the motor, which links with the main magnetic field and results in low speeds and high fluctuations. In this paper, a threedimensional finite element model of the two-degree-offreedom direct drive induction motor is developed to determine the rotary coupling magnetic field and its effect on the motor. The distribution of the rotary coupling magnetic field is calculated qualitatively based on a simplified model, and its variation law is investigated based on the changes of the induced voltages in a special coupling model. Moreover, the relationship between the rotary coupling magnetic field and the motor speed is determined by the rotary coupling coefficient. A test platform is applied to verify the coupling model and its results. |
| Author(s): | H. Feng, J. Si, Z. Cheng, C. Gao, W. Cao |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 11 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2376 KB |