ACES Publication Search
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| Title: | ACES Journal June 2025 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1967 KB |
| Title: | ACES Journal June 2025 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 255 KB |
| Title: | ACES Journal June 2025 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 17944 KB |
| Title: | Novel Strategies for Efficient Computational Electromagnetic (CEM) Simulation of Microstrip Circuits, Antennas, Arrays, and Metamaterials Part-II: Characteristic Basis Function Method, Perfectly Matched Layer, GPU Acceleration |
| Abstract: | As mentioned in Part-I [1], rapid prototyping plays a critical role in the design of antennas and related planar circuits for wireless communications, especially as we embrace the 5G/6G protocols going forward into the future. Existing commercial software modules are often inadequate for this task in the millimeter-wave range since the memory requirements and runtimes are often too high for them to be acceptable as design tools. Using approximate equivalent circuit models for various components comprising the antenna and the feed system is not the answer either, because these models are not sufficiently accurate. Consequently, it becomes necessary to resort to the use of more sophisticated simulation techniques based on full-wave solvers that are numerically rigorous, albeit computer-intensive. Furthermore, optimizing the dimensions of antennas and circuits to enhance the performance of the system is frequently desired, and this often exacerbates the problem since the simulation must be run a large number of times to achieve the performance goal, namely an optimized design. Consequently, as pointed out earlier, it is highly desirable to develop accurate yet efficient techniques, both in terms of memory requirements and runtimes, to expedite the design process as much as possible. In the first part of this paper [1], we presented three strategies to address these issues, mostly related to Green’s Functions of layered media.We have shown that the proposed techniques are not only useful for antennas and printed circuits on layered media but also for antennas embellished with metamaterials for the purpose of their performance enhancement. In this sequel to Part-I, we present several other Efficient Computational Electromagnetic (CEM) simulation strategies for expediting the runtime and improving the capability of handling large problems that are highly memory-intensive. These include a domain decomposition technique, which utilizes the Characteristic Basis Function Method (CBFM); the T-matrix approach which is also useful for hybridizing Finite Methods (FEM or FDTD) with the Method of Moments (MoM); Mesh truncation in Finite Method by using a conformal Perfectly Matched Layer (PML); and Graphics Processing Unit (GPU) acceleration of MoM and FDTD codes. |
| Author(s): | R. Mittra, T. Marinovic, O. Ozgun, S. Liu, R. K. Arya |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 3479 KB |
| Title: | A Stable Subgridding 2D-FDTD Method for Ground Penetrating Radar Modeling |
| Abstract: | The subgridding finite-difference timedomain (FDTD) method has a great attraction in ground penetrating radar (GPR) modeling. The challenge is that the interpolation of the field unknowns at the multiscale grid interfaces will aggravate the asymmetry of the numerical system which results in its instability. In this paper, an explicit unconditionally stable technique for a lossy object is introduced into the subgridding FDTD method. It removes the eigenmodes of the coefficient matrix which make the algorithm unstable. Therefore, the proposed approach not only maintains the advantages of simple implementation of the traditional FDTD method but also adopts a relatively large time step in both coarse and fine grid, which breaks through the restriction of the Courant-Friedrichs-Lewy (CFL) stability condition. The proposed method is applied in simulating the transverse magnetic (TM) wave backscattering of the two-dimensional buried objects in lossy media. Its accuracy and efficiency are examined by comparison with conventional FDTD and subgridding FDTD approaches. |
| Author(s): | X. Y. Zhang, R. L. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 1540 KB |
| Title: | Sparse Array Optimization Based on Modified Particle Swarm Optimization and Orthogonal Matching Pursuit |
| Abstract: | This paper addresses the low degree of freedom in optimization, primarily attributed to the conventional antenna array optimization methods that solely focus on the optimization of element positions, without considering the influence of element excitations. To address this issue, a sparse array optimization method is proposed based on modified Particle Swarm Optimization (PSO) algorithm and Orthogonal Matching Pursuit (OMP). This method simultaneously optimizes both the element positions and excitations to achieve the desired pattern. Initially, the compressive sensing principle is employed to establish a compressive sensing optimization model for the antenna array. Subsequently, OMP is utilized to simultaneously optimize the element positions and excitations within the antenna array. An improved PSO algorithm is then applied to iteratively update the obtained parameters, thereby further enhancing the peak sidelobe level. Experimental results demonstrate that the proposed algorithm can achieve satisfactory optimization performance. |
| Author(s): | D. Li, Q. Guo |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 2340 KB |
| Title: | A Brief Review of Non-invasive Systems for Continuous Glucose Monitoring |
| Abstract: | This paper explores the pros and cons of using Vector Network Analyzers (VNAs) and radar systems for non-invasive glucose concentration testing. While VNAs provide precise measurement capabilities, radar systems offer a more portable and cost-effective solution. The research discusses the application of both technologies in medical settings, focusing on their potential for glucose monitoring and the challenges associated with each. This paper also considers radar unit options for experimental setups below 40 GHz, with a focus on simulations for glucose concentration detection in finger tissues using the 3-term Debye model. |
| Author(s): | L. K. Elmiladi, A. Z. Elsherbeni, P. H. Aaen |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 2479 KB |
| Title: | Ultra-thin Coating Materials Sensor Based on Constitutive Parameters Near-zero Media |
| Abstract: | Microwave absorbing materials, which serve as essential functional components, are increasingly vital to stealth systems in military equipment. Accurate measurement of the electromagnetic parameters of absorbing coatings is crucial for achieving stealth effects. This study introduces a high-precision curved microwave sensor based on constitutive parameters near-zero (CPNZ) media, which uses thickness and complex permittivity as key test parameters. The complex permittivity and thickness of several typical absorbing materials were evaluated and benchmarked against other sensors. The detection limit of a CPNZ sensor for curved thickness is 0.5 mm, and the relative error of relative dielectric constant is less than 8%. Given the material thickness and resonant frequency, the relative error in the inversion of the dielectric constant is less than 3%. The calculated values closely correspond with the reference values, highlighting the CPNZ sensor’s enhanced accuracy and reliability for material characterization. |
| Author(s): | S. H. Jia, Y. W. Mao, Q. Y. Li, Z. J. Gao, Y. J. Zhou |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 2473 KB |
| Title: | An Angularly Stable and Polarization Insensitive Miniaturized Frequency Surface for WiMAX Applications |
| Abstract: | This paper presents a miniaturized, polarization insensitive and angularly stable frequency selective surface (FSS) for WiMAX (3.5 GHz) applications. The proposed FSS structure improves upon conventional curved units by incorporating 45◦ tilted dipoles with extended lengths to increase the effective electrical size. The proposed FSS is printed on float glass with a dielectric constant of 8. The unit cell dimensions are 0.062λ0×0.062λ0 (where λ0 is the free space wavelength at the first resonant frequency). It exhibits a bandstop characteristic at 3.5 GHz with a bandwidth of 540 MHz (-10 dB). This FSS demonstrates a stable frequency response under incident angles ranging from 0◦ to 80◦ for both horizontal and polarization angles. Furthermore, the proposed structure is further analyzed through the derivation of an equivalent circuit model. Finally, a prototype of adequate size is fabricated to validate the simulation results. Both the simulation and measured results confirm the stable performance of the proposed FSS. |
| Author(s): | Z. Wang, H. Zhu, D. Guo, X. Gan, X. Lyu |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 4840 KB |
| Title: | Compact Single and Dual-Band Branch-Line Coupler with Effective Fractional Bandwidth for Wireless Communication Systems |
| Abstract: | Multiple wireless communication systems make use of a branch-line coupler (BLC), which is a passive microwave component. For the purpose of splitting and combining microwave signals, as well as providing a 90-degree phase shift between the output ports, this 4- port device is made from four quarter-wavelength (λ/4) transmission lines. Having recently developed a dualband branch-line coupler (DBBLC), there has been a lot of attention paid to this development. When it comes to getting dual-band (DB) functioning of a BLC, one of the most common approaches is stub loaded transmission lines. For the BLC, stubs may be positioned either in the center of the arms or at the input of the arms. Stepped-impedance stubs, orthogonal coupled branches, and coupled lines are some of the strategies that have been shown to be effective in achieving DB functioning of a coupler. Through the utilization of the Elongated T-Shape Transmission Line (ETSTL), this work presents a one-of-a-kind design for each single-band branch-line coupler (SBBLC) and DBBLC that is of a compact proportion. Based on the information presented in this article, the SBBLC operates at a frequency of 0.9 GHz, whereas the DBBLC operates at 0.9 and 2.4 GHz. Using a fractional bandwidth (FBW) of 44%, the coupler that has been proposed is able to function at both 0.9 GHz (GSM) and 2.4 GHz (wireless). Efforts are done on reducing the size of the coupler to be ready for fabrication. |
| Author(s): | G. Srividhya, S. Maheswari |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 2898 KB |
| Title: | De-embedding Technique for Extraction and Analysis of Insulator Properties in Cables |
| Abstract: | This work utilizes the Nicolson-Ross-Weir (NRW) method to analyze the frequency-dependent material properties of the insulator inside cables. These properties include ε(f ), μ(f ), and tanδ. Common methods for this analysis include the open-ended coaxial probe method, free space method, resonant method, and transmission/reflection line method. Each method has a suitable structure and may require additional samples for measurement. Our proposed method can calculate the real material properties of the insulation after foaming in the cable following extrusion, up to 40 GHz. This study also compiles the effects of various factors on the extraction of material parameters and provides a detailed analysis of potential sources of error. We observed that variations in production can introduce discrepancies after de-embedding, which can result in anomalies at the dissipation factor curve. Finally, we propose a correction method that effectively improves the accuracy of the extracted dielectric constant. |
| Author(s): | W.-H. Tsai, D.-B. Lin, P.-J. Lu, T.-F. Tseng |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 3753 KB |
| Title: | Investigations on the Influence of Augmented Rail Geometry on Rail Gun |
| Abstract: | This paper investigates the effect of augmented rail geometry on rail gun key parameters such as mutual inductance gradient between the main and augmented rail (M’), maximum current density, and maximum magnetic flux density distribution in the rail crosssection, as well as repulsive force acting on the rails. The research study was conducted using a rectangular main rail with several augmented rail designs, including rectangular T, rectangular E, rectangular U, rectangular Convex, and rectangular Concave under inward and outward modes. The ANSYS MAXWELL 2-D eddy current field solver, which computes the magnetic field distributions for a given configuration using the finite element method, was used to calculate the rail gun essential parameters. Using the obtained results, a comparison study was conducted. It was found that the rectangular main rail with the inward circular convex augmented form rail crosssection had a greater value of M’ than other geometries; hence, it could be utilized to increase the armature’s velocity. |
| Author(s): | M. N. S. Kumar, R. Murugan, J. Lydia, S. L. S. Vimalraj |
| File Type: | Journal Paper |
| Issue: | Volume: 40 Number: 6 Year: 2025 |
| Download Link: | Click here to download PDF File Size: 2177 KB |