ACES Publication Search
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| Title: | ACES Journal April 2025 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1966 KB |
| Title: | ACES Journal April 2025 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 266 KB |
| Title: | ACES Journal April 2025 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 17851 KB |
| Title: | Fast Direct LDL′ Solver for Method of Moments Electric Field Integral Equation Solution |
| Abstract: | This paper proposes a new fast direct solver using the block diagonalization method. In our proposed method, the symmetric half single-level compressed block matrix is factorized using the diagonalization method into block diagonal and upper triangle block LDL′ format where, due to symmetric property, L is a transpose of L′. The far-field blocks in the upper triangle row block are merged and compressed using Adaptive Cross Approximation (ACA) and QR factorization. The solution consists of solving the diagonal block matrix and matrix-vector multiplication of the compressed row blocks of the upper triangle matrices. Our results show that the factorization cost and memory scales to O(N1.5) and the solution process scales to O(N). The method generates an efficient solution process for solving largescale electromagnetics problems. |
| Author(s): | Y. K. Negi, N. Balakrishnan, S. M. Rao |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 481 KB |
| Title: | Surface Integral Equations in Computational Electromagnetics: A Comprehensive Overview of Theory, Formulations, Discretization Schemes and Implementations |
| Abstract: | Computational electromagnetics based on surface integral equations provides accurate and efficient solutions for three-dimensional electromagnetic scattering problems in the frequency domain. In this review paper, we first introduce a complete and detailed theoretical analysis of the surface integral equation method, including different properties of the corresponding integral operators and equations. Using a pedagogical approach that should appeal to electrical engineers, we provide a systematic and comprehensive derivation of the different formulations found in the literature and discuss their advantages and pitfalls. Additionally, we provide a mathematical overview of the corresponding function spaces that clarifies the importance of correctly combining basis and testing functions and we examine the various aspects of discretization schemes, such as the Green’s function singularity subtraction and the application of different testing methods. Moreover, we assess alternative formulations and discretization procedures and draw particular conclusions about them, by comparing numerous examples and results from previously published works. Finally, we provide a detailed |
| Author(s): | P. S. Mavrikakis, O. J. F. Martin |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1875 KB |
| Title: | Superior Accuracy of the Normally-integrated MFIE Compared to the Traditional MFIE |
| Abstract: | An alternative method of moments discretization of the magnetic field integral equation (MFIE) uses testing functions inside the target and in a plane normal to the target surface. This approach is adapted to targets modeled with flat-faceted patches. A comparison with traditional numerical solutions of the MFIE that use testing functions on the target surface shows that the normally-integrated MFIE formulation produce far fields that are more accurate than those obtained from the traditional MFIE. The alternate approach can be made free from internal resonances and that approach is often more accurate than the combined field integral equation. |
| Author(s): | A. F. Peterson, M. M. Bibby |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 2007 KB |
| Title: | Advanced Physical Optics-inspired Support Vector Regression for Efficient Modeling of Target RCS |
| Abstract: | This paper proposes an advanced physical optics-inspired support vector regression (APOI-SVR) for efficiently modeling the radar cross section (RCS) of conducting targets. Specifically, an improved physical optics-inspired kernel function is newly proposed by introducing two angular frequency parameters, thereby enhancing the capability of characterizing the various fluctuation patterns in RCS with respect to observation angles. Furthermore, considering the critical role of data preprocessing in facilitating the model’s ability to learn the underlying RCS patterns accurately, a physics-based data preprocessing method is introduced. Numerical validations based on two exemplary targets demonstrate that APOI-SVR effectively reduces the predictive root mean square error (RMSE) by over 24.7% compared with the benchmark model. Afterward, APOI-SVR is adopted to quickly establish the RCS feature map of an aircraft model, the results show that it is comparable to numerical simulations in accuracy but less than one-tenth in time cost, indicating the practicality of APOI-SVR for efficiently analyzing the RCS characteristics of targets. |
| Author(s): | C. Shi, R. Cai, W. Dong, D. Xiao |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1006 KB |
| Title: | Compressing Electromagnetic Field by Rational Interpolation of the Spherical Wave Expansion Coefficients |
| Abstract: | It is of great significance to obtain the electromagnetic field radiated by an antenna or scattered by an object over a frequency band. But this data often occupies so large a memory that cannot be applied readily. This paper proposes to compress the field based on the spherical harmonic transformation (SHT) and rational interpolation. First, the tangential electric field over a sphere surrounding the antenna is obtained by simulation or measurement. Then, this field is converted into the spherical harmonic coefficients, which are sparse discrete spectra. Finally, these coefficients are interpolated over the whole frequency band with only a few sampling points. Numerical examples show that the proposed algorithm can compress the data of the near field of a rectangular waveguide antenna by about 17278 times, and those of the far field scattered from an UAV by about 103 times. |
| Author(s): | H. Yuan, P. Yang, N. Wang, Y. Ren, S. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1645 KB |
| Title: | Design of 3-Bit Angle-insensitive RIS for 5G Communication Systems |
| Abstract: | This paper introduces a 3-bit reconfigurable intelligent surface (RIS) design characterized by its unique angle-insensitive properties for 5G communication systems. The proposed configuration provides eight distinct phase states enabled by the states of two varactors with an applied bias voltage. The design of the unit cell with double centric square split ring resonators and the formation of the RIS with a 5x5 array have been presented. A detailed analysis of the RIS performance has been conducted using the CST 3D electromagnetic simulator to study the reflection amplitude and phase responses. It is demonstrated that the results show a phase range of up to 315 degrees, along with eight distinct states exhibiting a stable interval of 45 degrees. This effectively covers incidence angles ranging from 0 to 60 degrees. |
| Author(s): | T. Islam, A. Eroglu |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1081 KB |
| Title: | Beam-reconfigurable Antenna Based on Planar Inductor with Mn-Zn Ferrite |
| Abstract: | This paper presents a beam-reconfigurable antenna design adopting distributed inductors, Mn-Zn ferrite, and static magnetic fields. The proposed antenna consists of one driven patch, two parasitic patches, and a full ground plane. Each parasitic patch is loaded with a distributed inductor with positive inductance. The patch antenna has a symmetric configuration and a broadside pattern. A Mn-Zn ferrite slab is added to one inductor to reduce its self-resonant frequency and change its inductance from positive to negative which results in unsymmetric field distributions and a tilted radiation beam. A static magnetic field is applied to the ferrite material further to adjust the tilted angle of the radiation beam. The proposed antenna works at five modes with reconfigurable beams of θ =0◦ (φ =0◦), 15◦ (φ =90◦, 270◦) and 28◦ (φ =90◦, 270◦). |
| Author(s): | M. Yin, C Ju, W.-H. Zong, S. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1089 KB |
| Title: | Extended Network Parameters for Transmission Line Networks Subject to External Field Illumination |
| Abstract: | Microwave network parameters are prevalently used in the modeling of transmission lines. It can characterize the interconnection of ports and is supported by most SPICE software. However, traditional microwave network parameters cannot characterize the role of external fields; this is a common concern in electromagnetic compatibility or electromagnetic interference analysis. In this paper, external excitation is treated as an additional port in the circuit. An extended network parameter is proposed to model the transmission lines excited by the external field. The extended network parameters can be used easily in the SPICE solver to analyze responses on linear or nonlinear loads. The proposed method is suitable for evaluating the electromagnetic interference of complex transmission line networks or PCBs, and it can use the advantages of circuit solvers for tuning or optimization with less computational burden |
| Author(s): | M. Zhang, C. Ma, B. Zhang, Y. Luo |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1520 KB |
| Title: | Cross-Coupled Wide Stopband SIW Bandpass Filter Loading Snake-shaped Slot |
| Abstract: | In this paper, a novel fourth-order bandpass filter is proposed and fulfilled, which is based on a crosscoupling structure achieved by etching snake-shaped slots between vias of adjacent SIW cavities. The gap of the vias’ wall between adjacent SIW cavities is used to achieve coupling between the two cavities. The length of the coupling gap can be adjusted to change the resonant frequency of TE101 mode to TE201 mode. The offset distance between the ports and the centerline is disclosed as a key parameter to suppress undesired modes, achieving wide stopband characteristics. The snake-shaped slot is loaded on the vias’ wall between SIW cavities for the enhancement of the electrical coupling, which produces a pair of transmission zeros (TZs) on either side of the passband, enhancing frequency selectivity. The filter design is validated through simulation, fabrication, and measurement of a fourth-order SIW filter with TZs. It is verified that the designed filter shows promising characteristics, with a center frequency of 24.1 GHz, an insertion loss of 0.52 dB, and a return loss exceeding 11.8 dB. It is observed that two TZs appear at 22.82 GHz and 25.15 GHz, respectively, each exhibiting a suppression level better than 20 dB. The designed filter shows potential applications in microwave and radio frequency circuits, as well as in wireless communication systems. |
| Author(s): | Y. He, Z. Ma, M. Wang, J. Huang, Y. Jiang |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1292 KB |
| Title: | SIW Cavity-backed Gain-enhanced Circularly Polarized Metamaterial-loaded Dual-band MIMO Antenna for WLAN and 5G Applications |
| Abstract: | This work proposes the development of a metamaterial-loaded circularly dual-band cavity-backed substrate integrated waveguide (SIW) MIMO antenna designed for the sub-6 GHz, emphasizing sub-6 GHz 5G and WLAN applications. The creation of dual operating bands is enabled via a modified dual split ring resonator (CSRR)-shaped slot that is etched into the SIW cavitybacked rectangular radiator. Additionally, the antenna incorporates 6x3 modified SSRR unit cells strategically located in front of the intended radiators along the yaxis. This arrangement enables circular polarization and enhances the gain of the proposed radiator at 3.3 GHz and 5 GHz. The metamaterial loading of the proposed antenna yields a gain of 5.5 dB at 2.4 GHz and 5.4 dB at 5 GHz. Further, the implementation of a CSRR electromagnetic bandgap (EBG) decoupling structure reduces the mutual coupling between the radiators. The antenna exhibits an exceptional diversity performance. The experimental validation of the system confirms its intended functionality. |
| Author(s): | I. Leo S., G. A. A. Mary, A. S. Mazhar, S. Mishra, G. Jothi |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 4 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 4921 KB |