ACES Publication Search
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| Title: | ACES Journal November 2023 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 1967 KB |
| Title: | ACES Journal November 2023 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 215 KB |
| Title: | ACES Journal November 2023 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 32113 KB |
| Title: | Analysis of Moving Bodies with a Direct Finite Difference Time Domain Method |
| Abstract: | This paper proposes an original and thorough analysis of the behavior of electromagnetic waves in the presence of moving bodies by using the finite difference time domain (FDTD) method. Movements are implemented by changing positions of the objects at each time step, through the classical FDTD time loop. This technique is suitable for non-relativistic speeds, thus for most encountered problems in antennas and propagation domain. The numerical aspects that need to be considered are studied. Then, different bodies in motion are examined: plane wave source with matching resistors, observation point, inclined partially reflecting surface (PRS), line source, and metallic cylinder illuminated by a plane wave. The results are compared with those of special relativity which are considered as the references. Some aspects of special relativity are present in the direct FDTD approach, such as the independence of the velocity of electromagnetic wave propagation with the speed of the source and Lorentz local time (with a different physical interpretation). It is shown that the amplitude of the electric field for a moving plane wave source does not increase with the speed of motion, if the impedance of the source is small. Moreover, for a moving scattering metallic wire, one can observe a phenomenon similar to shock waves. |
| Author(s): | M. Marvasti, H. Boutayeb |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 21509 KB |
| Title: | Physics-informed Neural Networks for the Resolution of Analysis Problems in Electromagnetics |
| Abstract: | Learning from examples is the golden rule in the construction of behavioral models using neural networks (NN). When NN are trained to simulate physical equations, the tight enforcement of such laws is not guaranteed by the training process. In addition, there can be situations in which providing enough examples for a reliable training can be difficult, if not impossible. To alleviate these drawbacks of NN, recently a class of NN incorporating physical behavior has been proposed. Such NN are called “physics-informed neural networks” (PINN). In this contribution, their application to direct electromagnetic (EM) problems will be presented, and a formulation able to minimize an integral error will be introduced. |
| Author(s): | S. Barmada, P. Di Barba, A. Formisano, M. E. Mognaschi, M. Tucci |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 1916 KB |
| Title: | A Parallel 3-D HIE-FDTD Method using the MPI Library |
| Abstract: | This paper presents the implementation of the parallel hybrid implicit-explicit finite-difference timedomain (HIE-FDTD) method using the Message Passing Interface (MPI) library. The method proves to be very effective in simulating large-scale three-dimensional electromagnetic problems with fine structures in one direction. For the decomposition of the computational volume in the HIE-FDTD method, an MPI Cartesian 2D topology is implemented, allowing arbitrary division of the volume in two directions. Derived data types provided in the MPI library are employed to optimize inter-process communication. High accuracy and efficiency are subsequently demonstrated through a numerical example of a frequency-selected surface (FSS). It shows that the proposed method is very suitable for parallel computing, and the parallel efficiency maintains above 80% for different numbers of processes. |
| Author(s): | Q. Nan, C. Mou, J. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 828 KB |
| Title: | Fractal Interpolation Function based Thin Wire Antennas |
| Abstract: | This paper presents an approach for the design of wire antennas based on fractal interpolation functions (FIFs). The interpolation points and the contraction factors of the FIFs are chosen as free parameters to modify the antenna geometry. The proposed structures’ gain and radiation pattern can be optimized using FIF parameters. Producible prefractal antennas obtained in the intermediate iterations of fractal generation have compact sizes compared to classical counterparts. The error in prefractal geometry and the original fractal is bounded, and can be determined in terms of the finest producible detail’s dimensions. The emerging structures have multiband behavior due to their self-similar and symmetric nature. To illustrate the approach, we have provided finite element based simulations for several prefractal antennas. |S11|, the gain, the radiation efficiency, the radiation patterns, and feed point impedances for the demonstrated antennas are calculated numerically. The results indicate that produced antennas can be used in applications that require limited mechanical size, multiple operating bands, and controlled radiation patterns. |
| Author(s): | G. Kalender, E. Y. Zoral, S. Gunel |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 7463 KB |
| Title: | Composite Scattering Study of Layered Rough Surface with Target based on CCIA |
| Abstract: | In this paper, a fast Cross Coupling iterative Approach (CCIA) is proposed for studying the composite scattering of the layered rough surfaces with buried target, which uses forward backward method (FBM) to solve the electric field integral equations (EFIE) of the layered rough surface and bi-conjugate gradient method (BI-CG) to solve the EFIE of the target, and the interaction between the rough surface and the target is achieved by updating the excitation term. The algorithm is applied to calculate the composite scattering coefficients of the rough surface with a buried target, the results match with those of the traditional numerical algorithm MOM while the error can be reduced to 10−3 by 6 iterations, and the convergence speed and calculation accuracy meet the requirements. The composite scattering coefficients and Angular Correlation Function (ACF) amplitudes of layered rough surface and dielectric targets with different conditions are calculated, and the effects of various factors such as target size and burial depth on the composite scattering characteristics are discussed. It is found that the buried targets will have a great influence on the scattering characteristics, weakening or neglecting the coupling between them will lead to larger errors. Moreover, the results show that ACF can suppress scattering from rough surfaces well, making the scattering characteristics of the target more obvious, which is important for detecting underground targets. |
| Author(s): | J. Zhang, H. Wei |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 2232 KB |
| Title: | Simulation Analysis of Electromagnetic Environment Effect and Shielding Effectiveness for VPX Chassis under Plane Wave Radiation |
| Abstract: | The chassis based on the VPX bus standard structure has been widely applied to the fields of vehicle, missile, radar, etc. In this paper, we analyze the electromagnetic environment effect on VPX chassis via the CST software, and investigate the electromagnetic coupling characteristics of VPX chassis under 20 v/m plane wave radiation according to the RS103 test defined in the MIL-STD-461G standard. By simulation, we analyze the electromagnetic coupling paths of the VPX chassis, find the key positions of the electromagnetic protection such as the air intake, air outlet, trapdoor, and panel gaps, and we propose the electromagnetic protective measures for the weak parts of the VPX chassis. The electromagnetic shielding effectiveness before and after protection design is evaluated. Finally, the simulation results are verified by the experiments. It has guiding significance for the electromagnetic protection design of VPX chassis. |
| Author(s): | H. Ni, H. Jiang, X. Li, Q. Jia, X. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 5606 KB |
| Title: | Design of a New Balanced Side Slotted Vivaldi Antenna with Director using Genetic Algorithm |
| Abstract: | Generally, side slotting and directional techniques can improve the performance of a conventional Vivaldi antenna (CVA), but the optimal structure and distribution of slots and directors may be irregular or even complex, requiring significant manual effort, thus limiting the design possibilities. In this paper, a genetic algorithm (GA) is introduced to assist in designing and optimizing a new type of balanced side slotted Vivaldi antenna with director (SSVAD). The methods of artificial intelligence make the process of searching for the optimal structure of such a multi-objective and multi-dimensional problem simpler and more diverse. The GA-generated SSVAD antenna consists of a CVA and 34 slots with varying lengths, as well as 5 metal strips. It has a compact size of 38.2×49×0.8 mm3 (or 0.32λL×0.41λL×0.007λL, where λL is the lowest operating frequency of 2.48 GHz). The measured results show that the antenna has a peak gain >0 dBi over 2.48- 10.88 GHz and >5 dBi over 4.6-10.88 GHz with S11<- 10 dB standard, and exhibits directional characteristics at most of the operating frequencies. Since the measured results are basically consistent with the simulation ones, the effectiveness of the designed scheme has been proven. |
| Author(s): | X. Zhang, Y. Hu, A. Zhan |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 46816 KB |
| Title: | Design of a Reconfigurable Band-notched Wideband Antenna using EBG Structures |
| Abstract: | A compact WLAN band-notched reconfigurable wideband antenna using two mushroom-like electromagnetic band-gap (EBG) structures is proposed in this paper. It is designed based on a dual wideband microstrip feed patch antenna with operating frequency bands of 2.2-3.7 GHz and 4.8-6 GHz. One of the EBG cells is positioned alongside the feed line, while the other EBG cell is laid on the back of the substrate. The patch or ground of the two EBG units are fed with a stronger current through a ground slot and a parasitic stub respectively, and the connections between the EBG structures and the antenna are controlled by loading a PIN diode with two 56 pF DC blocking capacitors. The advantage of this proposed design is that the antenna and the EBG unit can be designed independently. The proposed antenna has an overall size of 35×46×1.6 mm3. When testing the S11 of the antenna, the influence of the bias circuit on the antenna is also considered. The measured results show that the proposed antenna can generate two notched bands of 2.3-2.49 GHz and 5.11- 5.51 GHz of WLAN, and the realized gain in the notch bands can be reduced to -2.65 dBi and -4.55 dBi, respectively, demonstrating its anti-interference characteristics, and can be applied in band notch broadband communication systems or anti-interference communication equipments such as unmanned aerial vehicles and radars. |
| Author(s): | X. Zhang, Z. Li, A. Zhan, Y. Me |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 1572 KB |
| Title: | CPW-Fed UWB-MIMO Antenna with Triple-band Notched and High Isolation using Double Y-shaped Decoupling Structure |
| Abstract: | A ultra-wideband (UWB) multiple-inputmultiple- output (MIMO) antenna using double Y-shaped decoupling structure with high isolation and triple notched-band is presented. The designed antenna composed of two orthogonally placed monopole elements, coplanar ground and double Y-shaped branch. The defected substrate structure is used to achieve miniaturization. By slotting successively C-shaped slot, semicircular slot and rectangular slot on the radiation patch and the ground, achieved three notched bands at 3.5 GHz WiMAX, 5.25 GHz WLAN, and 7.5 GHz X-band. The proposed antenna can operate in range of 2.56-12 GHz with triple notched bands of 3.31-3.96 GHz, 4.58-5.67 GHz and 6.57-8.16 GHz. Considering all the results, it can be concluded that the antenna presented has a great performance in terms of good radiation, high isolation (>24 dB), a low level ECC (<0.01) and a high DG level (>9.99), which proves the presented antenna has good prospect in UWB-MIMO systems. |
| Author(s): | C. Du, H. Peng |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 8716 KB |
| Title: | Analytical Model of an E-core Driver-pickup Coils Probe Applied to Eddy Current Testing of Multilayer Conductor |
| Abstract: | An analytical model of an E-core driverpickup coils probe located above a multilayer conductor containing a hidden cylindrical conductor is presented. The truncated region eigenfunction expansion (TREE) method is used to deal with the axial symmetry problem, and the closed-form final expression of the induced voltage in the pickup coil is derived. The changes of the induced voltage in the pickup coil due to the hidden cylindrical conductor are examined and calculated in Mathematica. Experiments and finite element simulations are performed and the results are compared with the analytical results, and they are in good agreement. |
| Author(s): | S. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 11 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 525 KB |