ACES Publication Search
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| Title: | ACES Journal May 2024 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 1968 KB |
| Title: | ACES Journal May 2024 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 185 KB |
| Title: | ACES Journal May 2024 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 17319 KB |
| Title: | Near Field Scatter from a Body of Revolution |
| Abstract: | Better understanding of electromagnetic wave propagation through vegetation and forest environments can be achieved with the aid of modeling and simulation. Specifically, modeling the coherent summation of electromagnetic waves due to both single scatter and multi-scatter effects. To accurately perform simulations in lower frequency bands, S-band and below, the Body of Revolution (BOR) Method of Moments (MoM) must be extended to calculate the scattered electric and magnetic near-fields from BOR in the presence of a plane wave. The near field interactions specifically occur during the various higher order scattering harmonics, i.e. 2nd order and greater harmonics. Additionally, the method must accurately capture scattered fields in the presence of a non-plane wave incident upon BOR. The focus of this study is modeling lossy dielectric BOR that are characteristic of vegetation and forest environments, e.g., cylinders representing tree branches. Although the formal electric and magnetic field scattering definitions are known, this report presents analytical formulations of near field scattering from BOR for this implementation of BOR-MoM. The scattered-field extensions are validated using the commercial software FEKO©, which simulates electromagnetic-wave scattering in 3D using MoM formulation of scattered fields. |
| Author(s): | E. C. Michaelchuck Jr., S. G. Lambrakos, W. O. Coburn |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 1243 KB |
| Title: | A Novel Proximal Policy Optimization Approach for Filter Design |
| Abstract: | This paper proposes a proximal policy optimization (PPO) algorithm for coupling matrix synthesis of microwave filters. With the improvement of filter design requirement, the limitations of traditional methods such as limited applicability are becoming more and more obvious. In order to improve the filter synthesis efficiency, this paper constructs a reinforcement learning algorithm based on Actor-Critic network architecture, and designs a unique filter coupling matrix synthesis reward function and action function, which can solve combinatorial optimization problems stably. |
| Author(s): | D. Fan, S. Ding, H. Zhang, W. Zhang, Q. Jia, X. Han, H. Tang, Z. Zhu, Y. Zhou |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 7175 KB |
| Title: | An Approach to the Implementation of Laplace and a Broadband Helmholtz Fast Multipole Method as an Application Independent Library |
| Abstract: | In this paper, we propose an approach to develop an application independent library of Laplace and Helmholtz fast multipole method (FMM) that can be used in different applications. For this purpose, we consider a generalized problem and a corresponding canonical problem (defined below). In the first main contribution, we show that it is possible to capture the essential characteristics of the canonical summation from sampling the values of certain potentials or signature functions. In the second main contribution, we show that partial derivatives of arbitrary orders acting on the far field can be represented as product of sparse matrices within the library, transparent to the user. Combining the two ideas, we show that once the FMM is configured to compute the canonical summation, the same setup can be used to work with a much wider, general class of problems. |
| Author(s): | S. Velamparambil |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 732 KB |
| Title: | Additional Acceleration of Antenna Optimal Characterization with Modeling Support |
| Abstract: | Optimal characterization is assumed to provide the best solution for the designed cost function among the possible solutions within the specified range. These processes can take a long time depending on the applications and computer hardware used. Here, the optimization process is supported by ANN modeling in order to shorten the current optimization processes as much as possible. For this purpose, the selection of design parameters of the bowtie patch antenna (BPA) is presented as a multi-dimensional, multi-objective modeling-supported design optimization problem. The operating frequency of the proposed antenna is 28 GHz, which is the standard for millimeter wave band and 5G technologies. To overcome this challenging design optimization, a new, fast and powerful optimization algorithm was used by modifying the non-dominant sorting genetic algorithm (NSGA)-III, and the optimal characterization of the microwave antenna design was achieved. Although the proposed method gives the same results compared to the existing process, it takes much less time. Therefore, it is possible to shorten the process and reduce costs without the need for extra applications or hardware. As a whole, the proposed design optimization process is an efficient, fast and reliable solution for all design problems. |
| Author(s): | A. Uluslu |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 695 KB |
| Title: | Development and Simulation of 26 GHz Beamforming Systems and Antenna Array 5G Network Base Stations |
| Abstract: | This paper focuses on designing a new structure of beamforming networks with an array antenna to control the beams. The 3×4 array antenna structure connects to the 3×3 Rotman lens beamformers to achieve this goal. The middle time delay line is around 14 mm. The design allows the x-axis to cover +25, 0, −25 degrees. Therefore, this work targets fifth generation (5G) application, which necessitates coverage in all directions by other base stations or users. Computer Simulation Technology (CST) microwave software facilitates the simulation process. The design begins with a single microstrip patch antenna, designed to function as an array antenna resonating at 26 GHz. The half-lambda separation (λ/2) among antennas gives 13.8 dBi gain with S11< −10 dB. The final structure for beamforming networks has a gain of 14 dBi. This work uses the Roger 5880 substrate, which has a dielectric constant of 2.2, a loss tangent of 0.0009, and a thickness of 0.127 mm. |
| Author(s): | A. A. M. A. Alazzawi, M. K. A. Rahim, O. Ayop |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 806 KB |
| Title: | Pulse Radiation Characteristics Prediction Method of Vivaldi Antenna based on Dipole Array |
| Abstract: | This paper presents a theoretical method to estimate the pulse radiation characteristics of Vivaldi antennas. Based on the surface current distribution and the ultra-wideband radiation principle, Vivaldi antenna is equivalently modeled as a dipole array, and the pulse radiation characteristics of a single Vivaldi antenna are brought out utilizing the spatial superposition approach. Then, the influences and results of the Vivaldi antenna pulse characteristics prediction with different construction ways of the dipole array and element numbers are furthermore investigated. Next, a quadratic spatial superposition technique is employed to complete the theoretical prediction for time-domain radiation characteristics of Vivaldi antenna arrays. Experiments and simulations are conducted separately to verify the proposed method for both single Vivaldi antenna and array. The validated results demonstrate that the dipole array-based theoretical prediction method can effectively capture the pulse radiation characteristics for both individual Vivaldi antenna and array operating in different modes, thereby addressing challenges associated with estimating radiation characteristics in ultra-wideband pulse applications. |
| Author(s): | B. Wang, H. Ning, H. Cai, Q. Liu, Y. Wang, Y. Yan |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 1905 KB |
| Title: | Compact-size Lightweight Beam-reconfigurable ESPAR Antenna with Parasitic Elements for UAV Applications |
| Abstract: | This paper presents a compact lightweight beam-reconfigurable antenna system for unmanned aerial vehicles (UAVs). The antenna system consists of a central active monopole element surrounded by eight parasitic elements, which can be controlled using PIN diodes to switch the beam across four elevation angles and eight azimuth beams. This beam-reconfigurable antenna system has several advantages over traditional UAV antennas, including light weight, efficiency, and compactness. The antenna system operates at 5.09 GHz and achieves a measured peak gain of 4.55 dBi, with a remarkably low weight of 9 g and a size of 1.00λ0×1.00λ0×0.22λ0. |
| Author(s): | M.-J. Kang, Y.-S. Choi, W.-S. Lee |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 2194 KB |
| Title: | A Low Profile Polarization-insensitive Multiple-band Metamaterial Absorber using a Slotted Octagonal Unit Cell |
| Abstract: | This paper introduces a thin, polarizationinsensitive (PI), and multiple-band electromagnetic metamaterial absorber (MMA). The unit cell of the MMA consists of a slotted octagonal metallic patch printed on an FR4 dielectric substrate, backed by a grounded metallic layer, and notably does not incorporate resistive lumped elements. The proposed MMA exhibits measured absorption, exceeding 75% for normal incidence, across frequency bands ranging from 2.22– 2.38 GHz, 6.86–7.24 GHz, 11.68–12.71 GHz, 14.1–14.8 GHz, and 15.47–16 GHz. The proposed MMA unit cell has dimensions of 0.21λ0 × 0.21λ0 and a thickness of 0.001λ0, where λ0 represents the wavelength corresponding to the lowest frequency at 2.22 GHz. The performance of the proposed MMA is simulated using CST Microwave Studio and MATLAB, and subsequently validated through experimental measurements. |
| Author(s): | M. Elhefnawy, K.-H. Kim, T.-H. Kim, W.-S. Lee |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 4857 KB |
| Title: | Introducing a 12/10 Induction Switched Reluctance Machine (ISRM) for Electric Powertrains |
| Abstract: | The induction switched reluctance machine (ISRM) is a novel electric machine that integrates the switched reluctance machine (SRM) with rotor inductive conductors to enhance performance in electric vehicle (EV) powertrain applications. In this topology, the rotor conductors act as a magnetic shield, diverting magnetic flux and preventing magnetic field lines from penetrating the rotor body. By engineering this design, short magnetic flux paths are created in both the stator and rotor of the electric machine. Since its recent introduction, the ISRM represents an emerging technology in the early stages of development. Similar to conventional SRMs, the ISRM can take on various topologies with different stator and rotor pole numbers. Minimizing rotor copper loss is a critical consideration in the ISRM design process. This paper examines two distinct ISRM topologies (12/10 and 12/8), and their characteristics are analyzed using the finite element method. Simulation results, including power density, torque density, efficiency, and copper loss, are presented and compared. Finally, the optimal ISRM topology is proposed for hybrid electric powertrains. |
| Author(s): | M. Joodi, M. Abbasian, M. Delshad |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 553 KB |
| Title: | Efficient MAPoD via Least Angle Regression based Polynomial Chaos Expansion Metamodel for Eddy Current NDT |
| Abstract: | In this article, a metamodeling approach based on non-intrusive polynomial chaos expansion (PCE) with least angle regression (LAR) method is used in boundary element analysis for a model-assisted probability of detection (MAPoD) study of eddy current nondestructive testing (NDT) systems. The LAR-PCE metamodel represents the NDT system model responses by a set of coefficients with the polynomial basis functions in lieu of pure kernel degeneration accelerated boundary element method (KD-BEM) based physical model. Both the computational accuracy and efficiency of the LAR-PCE metamodel over the ordinary least squares (OLS) based PCE metamodel are demonstrated by testing the 3D eddy current NDT benchmarks with different system setups, flaw lengths and widths. The simulation results show two digits accuracy of the PoD metrics compared with the ones achieved by the KD-BEM based physical model as the benchmark. The LAR-PCE metamodel has remarkable improvements in computational efficiency over the OLS-PCE metamodel and accelerates the MAPoD study. |
| Author(s): | Y. Bao, J. Qiu, P. Gurrala, J. Song |
| File Type: | Journal Paper |
| Issue: | Volume: 39 Number: 5 Year: 2024 |
| Download Link: | Click here to download PDF File Size: 4986 KB |