ACES Publication Search
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| Title: | ACES Journal February 2022 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 1969 KB |
| Title: | ACES Journal February 2022 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 389 KB |
| Title: | ACES Journal February 2022 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 14813 KB |
| Title: | Formulation of Iterative Finite-Difference Method for Generating Large Spatially Variant Lattices |
| Abstract: | A new numerical method to generate spatially variant lattices (SVLs) is derived and implemented. The algorithm proposed solves the underlying partial differential equations iteratively with an update equation derived using the finite-difference method to obtain an SVL that is continuous, smooth, and free of unintended defects while maintaining the unit cell geometry throughout the lattice. This iterative approach is shown to be more memory-efficient when compared to the matrix-based approach and is, thus, suitable for the calculation of large-scale SVLs. The iterative nature of the solver allows it to be easily implemented in graphics processing unit to parallelize the computation of SVLs. Two spatially variant self-collimating photonic crystals are generated and simulated to demonstrate the functionality of the algorithm as a tool to generate fully threedimensional photonic devices of realistic size. |
| Author(s): | M. F. Martinez, J. J. Gutierrez, J. E. Touma, R. C. Rumpf |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 1977 KB |
| Title: | A Memory-Efficient Hybrid Implicit–Explicit FDTD Method for Electromagnetic Simulation |
| Abstract: | As the explicit finite-difference timedomain (FDTD) method is restricted by the Courant-Friedrich-Levy (CFL) stability condition and inefficient for simulation in some situations, implicit methods are developed. The hybrid implicit-explicit (HIE) FDTD method is one popular method among them. In this paper, a memory-efficient HIE FDTD method is designed for electromagnetic simulation. The proposed HIE-FDTD method is based upon the divergence relationship of electric fields, nearly reduces one field component, and realizes a memory reduction rate of 33% approximately. Two numerical experiments are carried out to validate the proposed method and the results indicate that the proposed memory-efficient HIE-FDTD method can work well. |
| Author(s): | F. Chen, K. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 1009 KB |
| Title: | Scalable and Fast Characteristic Mode Analysis using GPUs |
| Abstract: | Characteristic mode analysis (CMA) is used in the design and analysis of a wide range of electromagnetic devices such as antennas and nanostructures. The implementation of CMA involves the evaluation of a large method of moments (MoM) complex impedance matrix at every frequency. In this work, we use different open-source software for the GPU acceleration of the CMA. This open-source software comprises a wide range of computer science numerical and machine learning libraries not typically used for electromagnetic applications. Specifically, this paper shows how these different Python-based libraries can optimize the computational time of the matrix operations that compose the CMA algorithm. Based on our computational experiments and optimizations, we propose an approach using a GPU platform that is able to achieve up to 16× and 26× speedup for the CMA processing of a single 15k × 15k MoM matrix of a perfect electric conductor scatterer and a single 30k × 30k MoM matrix of a dielectric scatterer, respectively. In addition to improving the processing speed of CMA, our approach provided the same accuracy as independent CMA simulations. The speedup, efficiency, and accuracy of our CMA implementation will enable the analysis of electromagnetic systems much larger than what was previously possible at a fraction of the computational time. |
| Author(s): | K. Alsultan, M. Z. M. Hamdalla, S. Dey, P. Rao, A. M. Hassan |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 1343 KB |
| Title: | A Difference Subgridding Method for Solving Multiscale Electro-Thermal Problems |
| Abstract: | Because of less memory costs and time consumption, a finite difference subgrid technique can effectively deal with multiscale problems in electromagnetic fields. When used in Maxwell equation, symmetric elements of the matrix are required; otherwise, the algorithm will be unstable. Usually, the electro-thermal problem also contains multiscale structures. However, the coefficient matrix of the heat transfer equation is asymmetric because the parameters of the equation vary with temperature and the Robbin boundary condition is used as well. In this paper, a three-dimensional (3D) finite difference subgridding method is proposed to simulate the electro-thermal coupling process of the multiscale circuits. The stability condition of the algorithm is deduced with a matrix method. And the efficiency and the effectiveness of the proposed subgridding approach are verified through square- and n-shaped resistances. Compared with the results of the COMSOL software and the traditional finite difference method (FDM), the proposed subgridding method has less unknowns and faster speed. |
| Author(s): | X. Zhang, R. Chen, A. Zhan |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 561 KB |
| Title: | Electromagnetic Characteristics Calculation of FSS by the Mixed Method FDTD/Extrapolation/Cascade Method |
| Abstract: | In this paper, a mixed method (MM) combining the advantages of finite difference time domain (FDTD), extrapolation, and matrix cascade methods is proposed. First, the hybrid algorithm combining the FDTD and extrapolation method is used to compute the electromagnetic characteristics of the single-layer frequency selective surface (FSS). Subsequently, matrix cascade method is used to calculate the electromagnetic characteristics of the multi-layer FSS. By introducing the Floquet theorem and considering the periodic boundary condition (PBC), absorbing boundary conditions (ABC) of the FSS, a three-dimensional model, is established. The computational results show that, while maintaining the same level of accuracy, the hybrid method greatly improves the computation speed and reduces the computer memory compared with the simulation software. It can provide an important reference for the subsequent study of the electromagnetic characteristics of the FSS. |
| Author(s): | Y. Wang, D. Zhou, Q. Liu, D. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 2383 KB |
| Title: | Bi-Static Radar Cross-Section Test Method by using Historic Marconi Set-up and Time Gating |
| Abstract: | In this paper, a low-cost, simple, and reliable bi-static radar cross-section (RCS) measurement method by using a historic Marconi set-up is presented. It uses a transmitting (Tx) antenna (located at a constant position, at a reference angle of q = 0º) and a moving receiver (Rx) antenna. A time gating method is used to extract the information from the reflection in the time domain; applying time filter allows removing the antenna sidelobe effects and other ambient noises. In this method, the Rx antenna (on the movable arm) is used to measure the reflected field in the angular range from 1º to 90º from the structure (printed circuit board, PCB) and the reference configuration represented by a ground (GND) plane of the same dimension. The time gating method is then applied to each pair of PCB/GND measurements to extract the bi-static RCS pattern of the structure at a given frequency. Here, a comparison of measurement results is carried out at 18 and 32 GHz with simulation ones indicating successful performance of the proposed method. It can be used as a low-cost, reliable, and available option in future measurement and scientific research. |
| Author(s): | Y. Azizi, M. Soleimani, S. H. Sedighy, L. Matekovits |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 891 KB |
| Title: | Synthesis of Thinned Planar Arrays Using 0-1 Integer Linear Programming Method |
| Abstract: | This paper proposes a fast optimization method for synthesizing thinned planar antenna arrays. A 0-1 integer linear programming (ILP) model was proposed for the antenna array optimization. This model mainly aims to minimize the peak sidelobe level (PSLL) and consider the design requirements of narrow beamwidth and high directivity, finally obtaining the optimal distribution of the turned “ON” element positions in the aperture. Several cases of planar array designs with different aperture sizes and scan angles were provided in the paper and compared with other popular algorithms. Numerical results showed that the new method can effectively optimize the thinned planar arrays, including large-scale arrays, while significantly reducing the computational cost and time |
| Author(s): | M. Wang, X. Ping |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 726 KB |
| Title: | PET-Based Instant Inkjet-Printed 4 × 4 Butler Matrix Beamforming Network |
| Abstract: | In this paper, a novel planar Butler matrix (BM) utilizing only 3 dB hybrid couplers and a crossover are implemented using a low-cost silver-nano inkjet printing technique. Unlike in the conventional design of BM where a phase shifter is required, this novel design does not need a phase shifter to be implemented. However, the use of delicate substrates like polyethylene terephthalate (PET) in the design makes it unique. This is not possible with the conventional thermal curing process, as PET substrate cannot be subjected to an excessively feverish temperature. The results obtained show good return loss and transmission coefficients better than 26.10 and 23.54 dB, respectively, at the center frequency. Similarly, an amplitude imbalance of less than 2.4 dB with phase mismatch within ±0.25º is achieved at the center frequency. The BM has a -10 dB bandwidth of 24.79% with a beam pattern produced at +13º,-40º, +40º, and -13º when ports 1-4 of the BM are energized. |
| Author(s): | S. A. Babale, S. K. A. Rahim, K. G. Tan, K. N. Paracha, A. D. Butt, I. Ali, S. H. Lawan |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 2236 KB |
| Title: | Study of the Combination Method and Its Application to Shrink a Patch Antenna Operating in the UHF Band |
| Abstract: | This work is focused on how to efficiently shrink a patch antenna operating in the UHF band. Five typical independent methods are first introduced that were solely used to realize a small patch antenna. A potential combination method is further discussed utilizing two or more of these five methods. One miniature patch antenna is experimentally demonstrated operating at 735 MHz using the combination method, in which both of shorting wall and complementary split ring resonators are applied in a reconciling way. A two-step optimization procedure is given to show how the antenna sizes can be significantly reduced with this combination method. The antenna is fabricated on a simple dielectric with a low εr of 2.2. The patch size is only 0.127λ × 0.123λ. The antenna efficiency is considerably high as 77% in measurement. |
| Author(s): | Q. Huang, X. Xu, R. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 4678 KB |
| Title: | Study on the Electromagnetic Interference of Shielded Cable in Rail Weighbridge |
| Abstract: | In view of the electromagnetic interference (EMI) of the signal shielded cable in the rail weighbridge, the interference source is analyzed on the basis of the field measurement and investigation, and methods of suppressing the crosstalk voltage of the shielded cable are proposed. First, the capacitive coupling model between the power line and the shielded cable is established, and the coupling model between the shielded layer and the core is developed. Later, the distribution parameters of the multi-conductor transmission line system are extracted by the commercial software ANSYS based on the finite element method. Then the coupling voltages of the shielded layer and the core can be calculated; compared with the measured results, the accuracy and effectiveness of the proposed method are verified. Finally, the EMI suppression methods are proposed and its effectiveness is verified. The EMI of the shielded cable is very common in engineering, and this method has a good reference value for solving the similar problems. |
| Author(s): | Y. Yang, F. Zhu, N. Lu, Y. Xiao |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 499 KB |
| Title: | Solid Characterization Utilizing Planar Microwave Resonator Sensor |
| Abstract: | This paper outlines the design and the implementation of a planar microwave resonator sensor for sensing application using the perturbation concept in which the dielectric characteristics of the resonator influence the quality factor (QF) and the resonance frequency. The designed sensor is fabricated using Roger 5880, and it is operating at 2.27 GHz in ranges of 1-3 GHz for testing solid materials. In addition, applying a specific experimental methodology, practical material is used as material samples such as those in Roger 5880, Roger 4350, and FR4. To investigate the microwave resonator sensor performance, an equivalent circuit model (ECM) is introduced. The proposed sensor has achieved a narrow bandwidth and high QF value of 240 at an operating frequency of 2.27GHz. Besides, the sensitivity and accuracy of the sensor is more than 80%, which makes this sensor an excellent solution to characterize the material, especially in discovering the material characteristics and quality. |
| Author(s): | A. J. A. Al-Gburi, Z. Zakaria, I. M. Ibrahim, R. S. Aswir, S. Alam |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 1984 KB |
| Title: | A Novel Technique for Dynamic Analysis of an Electromagnetic Rail Launcher using FEM Coupled with Simplorer |
| Abstract: | The performance of a rail gun depends on the current density distribution over the rail and armature as it determines the force that accelerates the projectile of the rail gun. A finite element method (FEM) coupled with Simplorer was developed to model and study the performance of the rail gun. The rail gun was modeled using an ANSYS eddy current field solver to determine the current density distribution and equivalent rail gun circuit for the given rail gun geometry. The armature velocity was then calculated using Simplorer by coupling the obtained equivalent rail gun circuit and exciting the rails using a capacitor-based pulsed power supply (PPS) system. The FEM coupled with Simplorer method was verified by numerical calculations for the rectangular rails and also with other researchers’ value, and that showed a good agreement between the results. Further, the current density distribution over rails and armature and velocity of the armature was calculated for different rail cross sections such as circular concave, circular convex, rectangular concave, rectangular convex, T-shaped concave, and T-shaped convex with a C-shaped armature. It was observed that the circular convex rail gun with C-shaped armature showed minimum current density distribution and gives a higher value of armature velocity compared with other rail gun structures. Thus, the circular convex armature was found to be suitable for the electromagnetic (EM) rail gun launching system. |
| Author(s): | J. Lydia, R. Karpagam, R. Murugan |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 1146 KB |
| Title: | Low-Frequency Transmitted Fields of a Source Inside a Magnetic Shell with Large Conductivity |
| Abstract: | The method to evaluate the transmitted fields of a source inside a simply connected magnetic shell with large but finite conductivity at low frequencies is proposed in this paper. When modeling the magnetic shell with large conductivity, it is regarded as a penetrable object. Electric field integral equation (EFIE) is selected for the exterior region problem and magnetic field integral equation (MFIE) is chosen for the interior region problem. Each operator is decomposed with loopstar functions to overcome the problem of low-frequency breakdown. Numerical results verify the accuracy of the proposed method. |
| Author(s): | S. Huang, G. Xiao, J. Mao |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 1840 KB |
| Title: | Prediction and Analysis of the Shielding Effectiveness and Resonances of a Cascaded Triple Enclosure Based on Electromagnetic Topology |
| Abstract: | A fast analytical method for predicting the shielding effectiveness (SE) and resonances of a parallelly–serially cascaded triple enclosure was proposed. Under the concept of electromagnetic topology, the observation points and the walls are treated as nodes and the space between them as tubes. An equivalent circuit model of the enclosures is derived in which the apertures on the front and rear walls of the two parallelly cascaded sub-enclosures are considered as a pair of three-port networks. To predict the SE at a particular monitoring point, we introduce the position factor. The results of the proposed method have a good agreement with the numerical methods while it is much faster. The proposed method can help in determining SE for cascaded enclosures. We can also find that the resonance effect affects each subenclosure through the apertures, which must be carefully considered in practice. |
| Author(s): | J.-C. Zhou, X.-T. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 8333 KB |
| Title: | Analysis of Nonlinear Characteristics and the Factors Affecting the Operation of the Active Magnetic Bearings Rotor System Considering Alford Force |
| Abstract: | Based on a test rig supported by active magnetic bearings (AMBs), this paper focuses on the study of the nonlinear dynamic characteristics and the factors affecting the operation of a rotor system under the coupling of magnetic bearing force and Alford force. In order to solve the nonlinear dynamic response of rotor system, a dynamic equation of the rotor which introduces Alford force and the electromagnetic force of the AMBs controlled by PID is established. By changing the control parameters (kP and kD), operation parameters (rotational speed), and structural parameters (clearance between impeller and volute), the equation is solved by using Runge-Kutta method. The results show that the rotor system exhibits complex nonlinear dynamic characteristics under the coupling action of Alford force and magnetic bearing force. The rotor system appears different dynamic behaviors such as single period, multi multi-period, and quasi quasi-period when changing the control parameters. Among all the control parameters, adjusting kD is more effective to ensure system stability. The amplitude of rotor increases from 8.2 μm to 11.9 μm with the increase of speed from 6000 rpm to 10,000 rpm, while that decreases from 9.6 μm to 8.2 μm with the increase of clearance between impeller and volute from 1mm to 4 mm. Therefore, under the influence of Alford force, apart from the control parameters, the operation parameters and structural parameters of magnetic bearings also affect the operation of the rotor system supported by the AMBs. |
| Author(s): | S. Zhang, J. Zhou, X. Han, Y. Ma |
| File Type: | Journal Paper |
| Issue: | Volume: 37 Number: 2 Year: 2022 |
| Download Link: | Click here to download PDF File Size: 7790 KB |