{"title":"Wide-Angle Electromagnetic Scattering Analysis of Object With Large-Scale Partial Modifications","authors":"Xiaoxing Fang;Yunyun Zhang;Jiagang Liu;Wen Tian","doi":"10.1109/LAWP.2025.3529506","DOIUrl":"https://doi.org/10.1109/LAWP.2025.3529506","url":null,"abstract":"This letter introduces a combined approximation (CA) method to address electromagnetic scattering analysis of partially modified objects, especially when partial modifications to an object are large scale. This method utilizes information from the initial impedance matrix to swiftly estimate the inverse of the modified impedance matrix, thereby avoiding the need of repetitive inversion. To tackle the wide-angle problem, the fast adaptive cross approximation algorithm is applied to compress the right-hand matrix affected by wide-angle incident excitation on partially modified objects. Then, the compressed low-rank matrix is incorporated into the CA method, enabling rapid solution of modified impedance matrix equation. Numerical results are provided to demonstrate the accuracy and effectiveness of the proposed method.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 5","pages":"1188-1192"},"PeriodicalIF":3.7,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Efficient Full-Wave Analysis of Lens Antennas With Arbitrary Feeder","authors":"J. Rubio;R. Gómez Alcalá;P. Robustillo;J. M. Gil","doi":"10.1109/LAWP.2025.3530101","DOIUrl":"https://doi.org/10.1109/LAWP.2025.3530101","url":null,"abstract":"The full-wave response of lenses with symmetry of revolution and arbitrary feeder, including mutual coupling, is efficiently obtained. For this purpose, a domain decomposition is carried out using concave or convex spherical ports, and the finite element method (FEM) for bodies of revolution is applied to the lens domain. The use of addition theorems for spherical modes allows the feeder to be arbitrarily translated and rotated. In this way, any modification in the lens or changes in the position of the feeder is quickly calculated, considering the mutual interactions between lens and feeder. The number of 2-D FEM simulations needed for lens analysis is discussed, as it will determine the efficiency of the method. Two very different examples are shown. One is based on a convex-to-concave spherical port connection, and the other on a convex-to-convex spherical port connection, for which a specific formulation is also presented.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 5","pages":"1203-1207"},"PeriodicalIF":3.7,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10841947","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Accurate Sparse Conformal Mesh Generation Method for Reducing Spatial Redundancy in Conformal FDTD","authors":"Yuan Fan;Yuhao Zhou;Yanan Liu;Han Liu;Xiao Xu;Liuge Du;Jia Zhao","doi":"10.1109/LAWP.2025.3527451","DOIUrl":"https://doi.org/10.1109/LAWP.2025.3527451","url":null,"abstract":"A 3D-CAD-based sparse conformal mesh generation (SC-MG) method is proposed to distinguish between conformal and nonconformal cells and calculate the volume fraction of perfectly matched object boundaries. A sparse conformal finite difference time domain (SC-FDTD) method specifically adapted to the SC-MG approach is also developed, which uses sparse storage to reduce the spatial redundancy of the FDTD iterative coefficients. The SC-MG method with lower time complexity is demonstrated to effectively resolve the distortion and loss of surface of the marching cubes-based method. The SC-FDTD has been shown to combine the benefits of low spatial redundancy of the staircase FDTD with the high accuracy characteristic of the conformal FDTD.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 5","pages":"1134-1138"},"PeriodicalIF":3.7,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143929803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design of Transmitting-Type Dual-Frequency Beam Steering Surfaces With Flexible Frequency Ratio","authors":"De Yin;Lei Zhu;Wanping Zhang;Bo Li","doi":"10.1109/LAWP.2025.3529041","DOIUrl":"https://doi.org/10.1109/LAWP.2025.3529041","url":null,"abstract":"Conventional dual-frequency beam steering surface (DF-BSS) can only adjust frequency ratio (FR) in a narrow range, and this letter presents a novel design concept for transmitting-type DF-BSS to broaden it. To reach this target, by utilizing two methods (choosing different resonant modes of the patch and adjusting the positions of loaded pins), the FR can be adjusted from 1.49 to 3.50. Based on mode excitation and inhibition theory, by placing the equivalent feeding ports at proper positions, the higher frequency (<inline-formula><tex-math>$f_{H}$</tex-math></inline-formula>) and the lower frequency (<inline-formula><tex-math>$f_{L}$</tex-math></inline-formula>) can work separately. To verify our design concept, two DF-BSS cases (Case Ⅰ: <inline-formula><tex-math>$f_{H}$</tex-math></inline-formula> = 11.1 GHz, <inline-formula><tex-math>$f_{L}$</tex-math></inline-formula> = 7.43 GHz, FR = 1.49; Case Ⅱ: <inline-formula><tex-math>$f_{H}$</tex-math></inline-formula> = 16.8 GHz, <inline-formula><tex-math>$f_{L}$</tex-math></inline-formula> = 4.8 GHz, FR = 3.5) with different beam steering angles are fabricated and measured. The bandwidths of the two cases both exceed 1.4%. The good agreements between measured results and expectations show the great potential of the proposed DF-BSS in rebuilding the propagating paths for electromagnetic waves.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 5","pages":"1168-1172"},"PeriodicalIF":3.7,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jo Tamura;Ryoto Ogushi;Hiroyasu Ishikawa;Hiroyuki Arai
{"title":"A Wideband Printed Dipole Antenna With Small Footprint Using a Miniaturized Microstrip-to-Coplanar Strips (CPS) Transition","authors":"Jo Tamura;Ryoto Ogushi;Hiroyasu Ishikawa;Hiroyuki Arai","doi":"10.1109/LAWP.2025.3529415","DOIUrl":"https://doi.org/10.1109/LAWP.2025.3529415","url":null,"abstract":"This letter presents a wideband printed dipole antenna for multistandard mobile communication. The antenna consists of a bow-tie shaped driven element, a parasitic radiator, and a new microstrip-to-coplanar strips transition. Unlike traditional transitions using a phase delay line, the new one utilizes a 180° hybrid having frequency-independent amplitude and phase balance. The replacement enhances the transition bandwidth, minimizes the footprint, and offers a simpler design with fewer design parameters. The measurement results show that the transition has a fractional bandwidth (<inline-formula><tex-math>$|S_{11}|< -10$</tex-math></inline-formula> dB) as wide as 91.9% in a back-to-back configuration. As a result, the antenna achieves the bandwidth of 61.6% with a constant gain of <inline-formula><tex-math>$text{4.2},text{dBi}pm 0.5$</tex-math></inline-formula> dBi and low cross-polarization level of better than −14.8 dB from 1.5 GHz to 2.5 GHz.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 5","pages":"1173-1177"},"PeriodicalIF":3.7,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Uniplanar, Quasi-Isotropic Folded Dipole Design Based on Hybrid GA-PSO Optimization","authors":"Shaopeng Wan;Bin He;Ping Lu;Xuehui Guan;Xiaoyan Zhang","doi":"10.1109/LAWP.2025.3528112","DOIUrl":"https://doi.org/10.1109/LAWP.2025.3528112","url":null,"abstract":"A uniplanar quasi-isotropic folded dipole is proposed by using a hybrid genetic algorithm and particle swarm optimization (GA-PSO) algorithm. The proposed antenna is evolved from a half-wave dipole, where the dipole is folded to achieve a pair of out-of-phase line sources and an orthogonal line source, thereby obtaining a quasi-isotropic radiation pattern. Based on GA-PSO algorithm, the bending position is optimized for the minimum gain difference. For demonstration, the dipole prototype operating at 915 MHz is designed and fabricated in which a parallel transmission line with comb-like structure is adopted to achieve good impedance matching. The measured result shows a gain difference of 2.81 dB, and the simulated value is 0.34 dB. Compared with other quasi-isotropic antennas, the proposed antenna has the merits of simple structure, low gain difference, and uniplanar structure.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 5","pages":"1158-1162"},"PeriodicalIF":3.7,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Characteristic Modes Analysis of Finite Periodic Array With Object Using Entire Domain Basis Function Method and ACA","authors":"Zi-Wen Tong;Ping Du;Gang Zheng","doi":"10.1109/LAWP.2025.3527927","DOIUrl":"https://doi.org/10.1109/LAWP.2025.3527927","url":null,"abstract":"In this letter, the entire domain (ED) basis function method is applied to the modes analysis of the composite finite periodic array-object. To construct the ED basis functions, the modes analysis of the array cell and object are performed, respectively. The eigenvalues and eigencurrents are obtained. The ED bases on the cell and the object are constructed using a few eigencurrents. Then, the reduced generalized eigenvalue equation (GEE) based on the ED bases will be obtained. By solving the equation, the characteristic modes of the composite structure can be analyzed. To reduce the fill-in time of matrices in the GEE, the adaptive cross approximation is introduced. Numerical results validate the accuracy of the proposed method. Moreover, the CPU time is dramatically reduced.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 5","pages":"1149-1152"},"PeriodicalIF":3.7,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143929809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Planar Array Beamforming Method Based on Transfer Learning","authors":"Jianming Huang;Rui Liu;Naibo Zhang;Yansong Cui","doi":"10.1109/LAWP.2025.3528039","DOIUrl":"https://doi.org/10.1109/LAWP.2025.3528039","url":null,"abstract":"A training method based on transfer learning is proposed in this article, which completes the beamforming task of a deep neural network based on ResNet through two stages: “data approximation” and “pattern approximation.” It is shown in the numerical simulations that the proposed method achieves better performance in beamforming tasks compared to the Dolph–Chebyshev method and the genetic algorithm. The model can generate complex excitation for arbitrary beam directions within the 0°∼45° off-axis angle range and control the sidelobe levels within the 20 dB to 40 dB range. Furthermore, with the support of a suitable computation platform, the synthesis process can be completed in about 0.04 seconds, which meets practical requirements in real-time synthesis, especially in the field of 5G communications.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 5","pages":"1153-1157"},"PeriodicalIF":3.7,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Compact Distance-Adaptive Wireless Power Transfer Using a Reconfigurable Auxiliary Coil","authors":"Weijun Hong;Jingchen Wang;Eng Gee Lim;Mark Leach;Zhao Wang;Rui Pei;Yi Huang","doi":"10.1109/LAWP.2025.3526916","DOIUrl":"https://doi.org/10.1109/LAWP.2025.3526916","url":null,"abstract":"In this letter, we propose a distance-adaptive wireless power transfer (WPT) system using a reconfigurable transmitter. The proposed transmitter incorporates a main coil and an auxiliary coil with adjustable currents. The auxiliary coil can be configured to directly control the coupling strength, which can mitigate excessive or insufficient coupling caused by distance variations. The distance adaptation capability of the proposed WPT system is verified through both simulations and experiments. Measurements of transmission coefficients show maximum increase of 64% at close range (15 mm) and 57% at long range (110 mm). The overall effective transmission range has been improved by 59%. The proposed design offers a simple yet effective approach to distance adaptation while maintaining compact system dimensions.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 5","pages":"1114-1118"},"PeriodicalIF":3.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143929763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}