Recent Articles
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Far-Field Characterization of High-Gain Antennas at 300-GHz Band Based on a Photonics-Based Near-Field Measurement
27 April 2026 Yusuke Tanaka, Kento Ishihara, Kota Miyake, Keizo Inagaki, Shintaro Hisatake presents a photonics-based near-field measurement approach for characterizing far-field radiation patterns of high-gain antennas operating at 300-GHz. Utilizing an electro-optic (EO) probe for electric near-field sensing, the system enables stable and precise acquisition of amplitude and phase over long measurement durations, which is essential for evaluating antennas with nominal gains exceeding 40 dBi. Far-field patterns reconstructed from near-field data using cylindrical mode expansion showed excellent agreement with direct far-field measurements conducted at an outdoor site with an antenna separation of 53 m. This result confirms that tabletop photonics-based near-field systems can serve as practical alternatives to outdoor far-field ranges at sub-terahertz frequencies.
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A Hybrid Multilayered Slot Array Antenna-Cavity Backed and Fed by Substrate-Integrated Groove Gap Waveguide (SIGGW) Network
23 April 2026 Panagiotis Petroutsos, Sofia Bakogianni, Stavros Koulouridis present a mixed multilayered cavity-backed slot array antenna for the 27 GHz band, fed by a substrate-integrated groove gap waveguide (SIGGW). The proposed antenna structure is based on a three-layer design, consisting of two dielectric substrates for the feeding network and cavity distribution layer, and a metal layer for a corrugated slot array antenna. In the presented multilevel antenna design, the feeding network and cavity layer are implemented by periodic “Mushroom”-type surfaces, creating electromagnetic band gap properties. This allows for easy assembly of the distinct printed layers without requiring an electrical contact or a bonding layer.
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Enhancing Axial Ratio Bandwidth and Gain in Microstrip Antennas Through a 3D-Printed Curved Substrate
22 April 2026 Giacomo Muntoni, Andrea Melis, Alessandro Fanti, Marco Simone, Giuseppe Mazzarella investigates the use of curved substrates, enabled by additive manufacturing (3D printing), for circularly polarized antennas. Curved substrates have proven to be a reliable approach for achieving impedance bandwidth enhancement and efficiency improvement in linearly polarized microstrip patch antennas. In this study, a novel application of this concept is investigated for circularly polarized antennas. Interestingly, the curved profile is found to provide significant benefits in this case, yielding a substantial increase in axial ratio bandwidth compared with the planar configuration (more than three times the original bandwidth), as well as the expected improvements in efficiency (and consequently gain) and impedance bandwidth.
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Miniature Scanning Chern Topological Antenna With Eliminated Trivial Photonic-Crystal-Insulator
16 April 2026 Ahmed Abdelraheem, Mostafa M. Elesawy, Alex D. Santiago-Vargas, Karim Seddik and Dimitrios Peroulis report the first experimental realization of a Chern periodic topological leaky-wave antenna (LWA). Unlike previous designs, our proposed structure utilizes a quasi-uniform aperture mechanism that completely eliminates the bulky photonic-crystal trivial side and interfaces directly to open space through radiating slots. Through optimizing the radiating slots period and width, we achieve full control over the line-wave dispersion and consequently the radiation characteristics. This approach yields full control over the scanning angle, including precise broadside placement, while reducing the electrical size by 45% compared to the smallest existing Chern LWAs.
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Additively Manufactured Waveguide Orthomode Transducer in the K-Band for Dual-Circular Polarization Broadband Satellite Antennas
09 April 2026 José Rico-Fernández, Guillermo Menéndez, Manuel Arrebola, Nelson J. G. Fonseca present a novel reconfigurable reflective surface capable of selective magnitude control at sub-6 GHz frequencies. Each unit cell integrates a low-power single-pole double-throw (SPDT) RF switch beneath the ground plane, providing two distinct impedance states that govern the reflection coefficient of the unit cell. The proposed configuration enables dynamic switching between reflective and absorptive modes at 5.50 GHz. A full system prototype comprising an 8×8 unit cells was fabricated and tested, the measured results exhibit good agreement with full-wave simulations, with the 1-bit (0°-180°) reflection phase control at 5.05 GHz and reflection magnitude switching between −2.4 dB and −26 dB at 5.50 GHz under TE-polarized excitation.
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A Superposition Method for Dual-Band Narrow-Wall Shorted-Slotted Waveguide Arrays at 3/4 GHz for Shared-Aperture ISAC Front-Ends
08 April 2026 Joko Suryana, Ali Rhomadoni, Lenni Yulianti and Annaz Vatica presents the design and implementation of a single-fed, dual-band narrow-wall shorted slotted waveguide array (SWA) operating at 3 GHz and 4 GHz within a shared aperture. Rather than treating the dual-band integration only as a geometric coexistence of two resonant slot families, this work introduces a coupling-aware multi-frequency formulation derived from the classical Elliott framework to interpret cross-family loading within a shared aperture. Within this formulation, the slot ensemble is partitioned into two frequency-selective families. Cross-family electromagnetic interactions are interpreted through a coupling perturbation term introduced within an extended multi-frequency impedance-matrix representation.
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A High-Order Fast Boundary Element Method as a Benchmarking Computational Framework for RCS Analysis of PEC Targets
07 April 2026 Omid Babazadeh, Ian Jeffrey, Constantine Sideris and Vladimir I. Okhmatovski propose a fast and accurate boundary element method framework for benchmarking the Radar Cross Section (RCS) computations for various Perfect Electric Conductor (PEC) targets, including sharp-edge models with electrically large sizes. The approach employs a high-order Chebyshev-based Boundary Integral Equation (CBIE) formulation of the Magnetic Field Integral Equation (MFIE). Acceleration is achieved using both the H -matrix framework and distributed parallelism for filling inadmissible blocks, substantially improving computational efficiency in both time and memory usage. We refer to the resulting solver as H -CBIE and demonstrate its O(hp) error convergence, scalability, and accuracy through extensive numerical results, h being the mesh element size and p the order of discretization. Localized hp -refinement is incorporated for sharp-edge problems to maintain accuracy near edges and junctions.
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Tri-Mode Hybrid Dielectric Resonator Antenna Fabricated via Laser-Based Selective Material Processing for WLAN Applications
06 April 2026 Zhenyi Shou, Nianyao Chai, Xiao Yang, Lin Li , Kewen Pan present a novel tri-mode hybrid dielectric resonator antenna (DRA) designed for wireless local area network (WLAN) applications. hrough a special DRA design, the antenna profile is compressed to 0.05 λ0 . TE y1+δ11 and TE y2+δ11 modes of a complex, irregular dielectric resonator are merged to provide the coverage of WLAN 5.2/5.8-GHz bands, while a quarter-wavelength monopole mode of an F-shaped metal strip is excited for the WLAN 2.4-GHz band.
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Antenna Characterization Techniques for Accurate Electromagnetic Imaging
26 March 2026 Yuri Álvarez López, Alicia Flórez Berdasco, Elena de Cos Gómez, Jaime Laviada Martínez and Fernando Las-Heras Andrés analyze the impact of the field radiated by the antennas of an electromagnetic imaging system on its imaging capabilities. The goal is to provide criteria for selecting appropriate imaging algorithms. Specifically, it evaluates whether conventional backpropagation methods, such as delay-and-sum or phase shift migration, are sufficient, or if more advanced techniques that consider the antenna characterization are required for accurate imaging. The capability of the more advanced imaging methods to enable the use of antennas that are not specifically designed for imaging applications is experimentally tested. In particular, imaging results obtained with an antenna commonly used for microwave imaging are compared against those achieved with two antenna prototypes not designed for imaging applications. Qualitative and quantitative analysis is conducted to assess the degree of improvement that can be achieved with the proposed methodology.
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Vertical Polarized Helicoid Array With Full Azimuth Beam-Scanning
12 March 2026 Yat Hin Chan, Hossein Mardani, Neil Buchanan and Vincent Fusco outlines the theory behind helicoid antenna array beamforming and the practical validation on an 8×8 helicoid antenna array. Design, simulation, and measurement are presented at 2.45 GHz. A practical method for obtaining the phase steering weights required to perform beam pointing over 360 degrees is presented. A specialised dipole was also developed, achieving 4.9 dBi and low mutual coupling. It was also shown by analysis, simulation and measurement that this type of array, unlike a planar array, does not exhibit beam pointing error, making it highly attractive for retrodirective applications when precision beam pointing is required.
