{"title":"A Fast and Generalizable ML-Assisted Framework for Full-Wave Inverse Scattering","authors":"Siyi Huang;Shuwen Yang;Haochang Wu;Shunchuan Yang;Xinyue Zhang;Xingqi Zhang","doi":"10.1109/TAP.2025.3577780","DOIUrl":"https://doi.org/10.1109/TAP.2025.3577780","url":null,"abstract":"This article proposes a novel machine learning (ML)-assisted framework for solving full-wave inverse scattering problems (ISPs) in inhomogeneous, high-contrast media. Traditional deterministic algorithms used to solve such ISPs face significant challenges due to their high computational cost, inherent nonlinearity, and strong ill-posedness. Recently, the introduction of ML methods has enabled the development of rapid solutions to this problem. However, these solutions’ limited out-of-distribution (OOD) generalization capabilities pose significant challenges for practical applications. To address these challenges, we propose a novel pathway to combine ML models with full-wave inversion (FWI). In this framework, ML models serve as auxiliary tools, supplying prior knowledge for use in FWI. A mathematically guaranteed bounds-generation algorithm is proposed to bridge ML models with FWI, and a limited-memory Broyden-Fletcher–Goldfarb-Shanno algorithm with bound constraints (L-BFGS-B) is introduced in FWI to incorporate these bounds. In contrast to the existing research, our framework leverages ML to enhance computational speed while preserving the interpretability and broad applicability of physical models, making it outstanding for OOD samples. We validate the framework across three numerical datasets and conducted rigorous ablation studies on each component to confirm its contributions. To further assess the robustness of the framework, we perform a noise stability study under perturbed conditions. In addition, we extend the framework to multifrequency and time-domain inversion schemes, thereby demonstrating its broad applicability across diverse FWI tasks. We also integrate transfer learning techniques to highlight the framework’s strong compatibility with emerging ML techniques.","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 9","pages":"6839-6854"},"PeriodicalIF":5.8,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Air-Filled High-Efficiency W-Band Metasurface Antennas Using the Microcoaxial Additive Manufacturing Process","authors":"Ruihua Liang;Le Chang;Cheng Guo;Guanghua Shi;Zhen Wang;Anxue Zhang","doi":"10.1109/TAP.2025.3576983","DOIUrl":"https://doi.org/10.1109/TAP.2025.3576983","url":null,"abstract":"Millimeter-wave and terahertz antennas require high manufacturing precision and low dielectric loss. As a new solution, micrometal additive manufacturing (M-MAM) technology can achieve multilayer pure copper structure, with planar pattern precision of up to <inline-formula> <tex-math>$5~mu $ </tex-math></inline-formula>m. In this work, a new nine-layer M-MAM process flow was used to fabricate a W-band metasurface antenna. The large metal and blank areas of the antenna structure were substituted by periodic rectangular metal posts to balance the electrostatic field across the wafer during the electroforming process. These structural changes ensure the uniformity of the layer thickness and help reduce the accumulation of errors. The measured 10-dB impedance bandwidth of the antenna is 22.5%, and a maximum peak gain of 13.7 dBi is achieved in an overall aperture size of <inline-formula> <tex-math>$1.43 lambda _{0} times 0.88 lambda _{0}$ </tex-math></inline-formula>. In addition, the front-to-back ratio (FBR) of the metasurface antenna is larger than 20 dB across the whole bandwidth. Thanks to the M-MAM technology that nearly eliminates the dielectric loss, the antenna achieved a maximum simulated radiation efficiency of 96%.","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 9","pages":"7045-7050"},"PeriodicalIF":5.8,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145036747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jan H. S. Bergman;Mikko Heino;Juha Ala-Laurinaho;Taneli Riihonen;Mikko Valkama;Ville Viikari
{"title":"Design of Aperture-Coupled Vivaldi-Antenna Array With Scan-Range-Improving Parasitic Resonators for Ka-Band","authors":"Jan H. S. Bergman;Mikko Heino;Juha Ala-Laurinaho;Taneli Riihonen;Mikko Valkama;Ville Viikari","doi":"10.1109/TAP.2025.3576489","DOIUrl":"https://doi.org/10.1109/TAP.2025.3576489","url":null,"abstract":"We present a linear Vivaldi-antenna array with a misalignment-robust nongalvanic transition and scan-range-improving parasitic resonators for 5G FR2-1 base-station applications. The array covers most of the Ka-band (26.5–40 GHz) on a scan range of <inline-formula> <tex-math>$pm 60 {mathrm {^{circ}}}$ </tex-math></inline-formula> with a total active reflection coefficient of below −10 dB and a scan gain of above 10 dBi. Furthermore, the parasitic resonators increase the scan range to <inline-formula> <tex-math>$pm 85 {mathrm {^{circ}}}$ </tex-math></inline-formula> between 30 and 35 GHz. A prototype of the array is measured and the performance is confirmed to coincide well with the simulations.","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 9","pages":"6955-6960"},"PeriodicalIF":5.8,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11030242","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"An Ultralow Profile Large Spaced Phased Array With Grating Lobe Suppression Capability by Exciting Leaky Wave Waveguide","authors":"Wei Chen;Shaoqiu Xiao","doi":"10.1109/TAP.2025.3575944","DOIUrl":"https://doi.org/10.1109/TAP.2025.3575944","url":null,"abstract":"In this communication, a design method for an ultralow profile, periodically large spacing phased array antenna capable of suppressing grating lobe is presented. We first propose and demonstrate a theoretical model for calculating the relationship between flat-topped element pattern and dispersion constants of bidirectional in-phase leaky wave. Then, our novel method of exciting metasurface leaky wave waveguide, not only proving the effectiveness of the aforementioned model but also offering the advantage of an ultralow profile compared with previous flat-topped pattern works. During the implementation process, a magnetic current source was used to excite bidirectional in-phase leaky wave, resulting in a quasi-circular aperture field distribution. Simultaneously, an approximate circuit model was established to explain the underlying radiation mechanism. Finally, through measurement and comparison, under the premise of an ultralow profile, our designed large spacing phased array with a period of <inline-formula> <tex-math>$0.9mathbf {lambda _{0}}$ </tex-math></inline-formula> and a scanning sector of ±20° demonstrates comparable grating lobe suppression performance across the operating band.","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 9","pages":"7069-7074"},"PeriodicalIF":5.8,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145036808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yang Wang;Tianxiang Wang;Xiangquan Zheng;Xinyu Hao;Xi Liao
{"title":"Millimeter-Wave and Sub-THz Radio Propagation Channel Measurements and Modeling in an Indoor Factory Environment for ISAC","authors":"Yang Wang;Tianxiang Wang;Xiangquan Zheng;Xinyu Hao;Xi Liao","doi":"10.1109/TAP.2025.3575564","DOIUrl":"https://doi.org/10.1109/TAP.2025.3575564","url":null,"abstract":"Integrated sensing and communication (ISAC) has been considered a promising technology in the sixth-generation (6G) system. An accurate and realistic wireless channel model is crucial for optimizing and evaluating ISAC systems and techniques. However, the ISAC channel characteristics have not been well understood, and sensing channels have not been well modeled in the existing standard-level channel models. In this article, extensive sensing and communication channel measurements are conducted in four representative indoor factory (InF) scenarios at 28, 38, and 132 GHz, in which over 2600 spatial channel impulse responses are collected. In light of the measurement results, physical parameters and insights in ISAC channels are comprehensively analyzed, including the temporal and spatial features, cluster-level characteristics, and correlation between the communication and sensing channels. Finally, a geometry-based stochastic model (GBSM) ISAC channel model combined sharing feature is proposed based on the 3GPP standard framework. Some special sensing properties, such as shared sensing clusters and sensibility probability, are novelly introduced to model the sensing channels. Simulation results demonstrate that the proposed ISAC channel model can be well-compatible with the 3GPP standards and offers promising support for ISAC technology evaluation.","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 9","pages":"6883-6898"},"PeriodicalIF":5.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. M. Kayser Azam;Mohamadariff Othman;Tarik Abdul Latef;Hazlee Azil Illias;A. K. M. Zakir Hossain;Yoshihide Yamada;Kamilia Kamardin;Mohamed Alkhatib;Mousa I. Hussein;Zamri Zainal Abidin
{"title":"Standalone Identification Antenna for Resonator Tag-Free Far-Field Chipless RFID Sensors","authors":"S. M. Kayser Azam;Mohamadariff Othman;Tarik Abdul Latef;Hazlee Azil Illias;A. K. M. Zakir Hossain;Yoshihide Yamada;Kamilia Kamardin;Mohamed Alkhatib;Mousa I. Hussein;Zamri Zainal Abidin","doi":"10.1109/TAP.2025.3574862","DOIUrl":"https://doi.org/10.1109/TAP.2025.3574862","url":null,"abstract":"In conventional chipless radio frequency identification (CRFID) systems, antennas and separate resonator tags work interdependently—resonator tags rely on antennas for data transmission, while antennas alone cannot perform radio frequency identification (RFID) operations without them. This research introduces, for the first time, a stand-alone identification antenna (SIDA), eliminating the need for supplementary resonator tags to independently perform CRFID functions in the far-field. SIDA is designed as a planar monopole antenna (PMA) in the ultrahigh frequency (UHF) range, employing a new mechanism of notch element concentration (NEC) on its patch. Intermingled coupling resonators (ICRs) are utilized as notch elements to generate multiresonating coding bits in far-field radiation. SIDA prototypes are fabricated on Rogers RO4003C substrate with distinctive 6-bit multiresonating codes (111111 and 111101) within the 0.78–1.38 GHz range. By eliminating the need for separate resonator tags, SIDA significantly improves conventional retransmission (ReTx)- and received signal strength (RSS)-based CRFID operations. Both in ReTx and RSS systems, SIDA is applied as resonator tag-free far-field CRFID sensor for the simultaneous detection of partial discharge (PD) defect in high-voltage (HV) systems and RF identification of PD-affected HV equipment. Experimental performances prove SIDA’s suitability as far-field CRFID sensor and its prospect in multipurpose smart sensing uses by eliminating the need for additional resonator tags.","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 9","pages":"6914-6927"},"PeriodicalIF":5.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145028001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Achromatic Multibeam Diffraction Based on Phase Gradient Metasurfaces","authors":"Yuxiang Wang;Yueyi Yuan;Shah Nawaz Burokur;Qiang Wang;Qun Wu;Kuang Zhang","doi":"10.1109/TAP.2025.3575275","DOIUrl":"https://doi.org/10.1109/TAP.2025.3575275","url":null,"abstract":"Metasurfaces have attracted extensive attention due to their excellent capabilities in wavefront manipulation. However, chromatic aberration, which is widely present in phase-modulated tuning metadevices, limits their applications in modern communication systems. Far-field achromatism has been explored but only considered for single-order diffraction. With increasing demands and studies on multibeam diffraction, including, but not limited to, phase-modulated metasurfaces and metagratings, most of them are not suitable for dispersion manipulation. In this article, we analyze the achromatic mechanism of the diffraction field and propose a feasible solution to coherently control the dispersion on multiorder diffractions simultaneously. The chiral phase is introduced in the meta-atom to engineer the dispersion characteristics. In addition, an achromatic dispersion metasurface is designed for dual-beam generation as proof of concept. The two beams with propagation direction −35° and +35° show good angle stability at the targeted frequencies of 7, 10, and 13 GHz. Moreover, the limitations on beam direction accuracy and metasurface aperture are also discussed. An improvement method that can greatly enhance the accuracy of diffraction angle is further proposed, where the deviation between actual beam angles and expected ones is reduced to below 0.8°, with a 73% enhancement. The proposed work builds up a major advance for diffraction management and shows great potential in wireless communications and radar detection.","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 9","pages":"6525-6534"},"PeriodicalIF":5.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145049808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 Compact, Broadband, Radar-Infrared Multispectral Stealth Antenna Based on Dual-Functional Polarization Conversion Metasurface","authors":"Jianing Yang;Yao Li;Jie Guo;Zhentian Wu;Ming-Chun Tang","doi":"10.1109/TAP.2025.3575299","DOIUrl":"https://doi.org/10.1109/TAP.2025.3575299","url":null,"abstract":"This communication presents a compact antenna which can realize broadband radar-infrared multispectral stealth. The antenna consists of a dual-layer structure: the top layer is an infrared shielding layer (IRSL) made up of periodically arranged square metal patches, while the bottom layer is a radar scattering layer (RSL) comprises a checkerboard pattern of polarization conversion metasurface (PCM) elements. The patch antenna is located in the central area of the RSL. At the central working frequency of 5 GHz, the overall dimensions of the antenna are <inline-formula> <tex-math>$2lambda _{0} times 2lambda _{0} times 0.09lambda _{0}$ </tex-math></inline-formula>. Measured results show that the proposed antenna (PA) operates within the 4.75–5.36 GHz band, achieving a maximum gain of 8.6 dB near 5.1 GHz. When the electromagnetic wave is vertically incident along the <italic>x</i> and <italic>y</i> polarization directions, the radar cross section (RCS) reduction exceeds 8 dB within the 4.44–12.76 GHz frequency range (94.5%) and 10 dB within the 4.45–12.62 GHz frequency range (85.5%). Moreover, the PA’s average infrared emissivity is 0.21. Experimental results show that antenna can control radiative thermal effectively, leading to a significant decrease in the apparent temperature observed under a thermal imager.","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 9","pages":"7057-7062"},"PeriodicalIF":5.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145036195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 High-Fidelity Radar Cross Section Analysis and Control Method of Phased Array Based on Impedance Modulation","authors":"Chan Bai;Shuai Zhang;Zixuan Song;Zepu Wang;Ruixue Zhang","doi":"10.1109/TAP.2025.3575617","DOIUrl":"https://doi.org/10.1109/TAP.2025.3575617","url":null,"abstract":"This article proposes a high-fidelity scattering control method for phased array based on analytical theory, which is applicable to radar cross section (RCS) reduction. Through theoretical derivation, an analytical relationship is established between the array radiation field, antenna-mode scattering field (AM-SF), and structure-mode scattering field (SM-SF). It is demonstrated that, based on analytical formulas, the AM-SF can be modulated into arbitrary scattering patterns using nonuniform termination impedance. The total scattering field (T-SF) is synthesized from AM-SF and SM-SF. Thus, the impedance network, corresponding to the modulated AM-SF, is designed to achieve T-SF control and port matching. Different from previous scattering reduction methods of phased array, the proposed method considers mutual coupling between elements and achieves high-fidelity scattering control while maintaining radiation performance. An eight-element microstrip patch antenna array is designed to validate the proposed method by reducing the RCS to the defined value at the desired angle or angular domain. Specifically, the RCS of the designed array is reduced to −60 dBsm at normal incidence or oblique incidence of −22°, −50 dBsm at oblique incidence of 13°, or to below −40 dBsm across the entire angular domain. There is only slight degradation in radiation gain compared to the reference array, and the scanning range still covers ±60°. The proposed high-fidelity scattering analytical method is well validated numerically and experimentally.","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 9","pages":"6871-6882"},"PeriodicalIF":5.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Institutional Listings","authors":"","doi":"10.1109/TAP.2025.3571659","DOIUrl":"https://doi.org/10.1109/TAP.2025.3571659","url":null,"abstract":"","PeriodicalId":13102,"journal":{"name":"IEEE Transactions on Antennas and Propagation","volume":"73 6","pages":"C4-C4"},"PeriodicalIF":4.6,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11026765","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144255655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}