Recent Articles
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Optically Transparent Single-Layer Dual-Frequency Dual-Polarization Metasurface Applied in Close Proximity to Smartphone Millimeter-Wave Phased Array Antenna Systems
07 March 2025 Wen Fu, Igor Syrytsin, Rocio Rodriguez Cano, Peiye Liu, Andrey Kobyakov, Gert Frølund Pedersen and Shuai Zhang propose an optically transparent single-layer dual-frequency dual-polarization metasurface operating at 28 GHz and 38 GHz to enhance millimeter-wave transmission through glass. The unit cell design of the proposed metasurface has three distinct pattern types: square annular, Jerusalem cross, and circular. The former pattern can independently control the low-frequency resonance, while the latter two can control the high-frequency resonance. The proposed metasurface can achieve a large incident angle of 60 degrees for electromagnetic waves in TE and TM polarizations. After the metal layer of the proposed metasurface is meshed, the transparency of the metasurface is significantly improved.
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A Wideband 4×4 Patch Array Antenna With Low Sidelobes for Radar-Based Obstacle Detection in Railway Transportation
05 March 2025 Thipamas Phakaew, Tiwat Pongthavornkamol, Danai Torrungrueng, Thomas Dallmann and Suramate Chalermwisutkul presents the design, fabrication, and measurement of a 4×4 patch array antenna for radar-based obstacle detection systems in railway transportation. Sidelobe suppression is achieved through amplitude tapering of sub-array elements in the E-plane and asymmetric power dividers in the feed network for the H-plane. The array antenna is framed by a coplanar ground conductor to further reduce sidelobes and fed by a coplanar waveguide port for enhanced impedance bandwidth. The proposed antenna offers an impedance bandwidth from 9.13 GHz to 9.76 GHz (6.3%) and a broadside gain of 18.15 dBi at the center frequency of 9.55 GHz. Sidelobe suppression exceeds 12.22 dB and 19.06 dB in the E- and H-plane, respectively.
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An Anisotropic Metamaterial Cover Layer for Scan Range Enhancement of Patch-Antenna Phased Arrays in Both Principal Planes
04 March 2025 Mohammad Soltani and George V. Eleftheriades introduces a metamaterial cover layer designed to extend the scan range of patch-antenna phased arrays in both principal planes without compromising directivity. The key innovation lies in the anisotropic properties of the cover layer which suppress the excitation of the fundamental surface-wave (SW) mode, effectively mitigating scan blindness within the desired angular range. This suppression mechanism is simply not possible with a conventional dielectric-slab wide-angle impedance matching (WAIM) layer.
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A Wideband and Low Sidelobe Magnetoelectric Dipole Antenna Array With Embedded Resistors
03 March 2025 Jianhui Huang and Kwai-Man Luk propose a simple and effective method, by using ‘0-1’ excitations, to reduce the sidelobe level (SLL) for a wideband magnetoelectric (ME) dipole antenna array. First of all, the multiple-population genetic algorithm (MPGA) is utilized to search optimal ‘0-1’ excitations for SLL reductions. Then, the ‘0’ and ‘1’ excitation can be achieved by incorporating the absorbing element embedded with a resistor and an ME dipole antenna element, respectively. Different from the traditional tapered excitation techniques, the proposed array utilizes an equal power divider to distribute the power to each element. Finally, a planar 16×16 stripline-fed antenna array according to the optimized array configuration is designed, fabricated, and measured.
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Compressed Sensing Digital MIMO Radar Using a Non-Uniformly Spaced SIW Sparse Receiver Array
27 February 2025 Cristian A. Alistarh, Symon K. Podilchak, Dave J. Bekers, Laura Anitori, Wim L. van Rossum, Rob Boekema, Iram Shahzadi, Mathini Sellathurai, John S. Thompson and Yahia M. M. Antar propose a compressed sensing (CS) digital radar system based on a sparse array design for use in automotive collision-avoidance applications. The proof-of-concept radar system offers an enlarged antenna aperture, employing fewer elements and can distinguish targets at an angular separation of only 2 degrees for a bandwidth of 6.25%. This resolution is made possible using a multiple-input multiple-output (MIMO) configuration from the original sparse array which was implemented and tested using substrate integrated waveguide (SIW) technology. More specifically, the total aperture size (of the effective virtual receiver array) is 23.5λ which is equivalent to a uniform-linear array (ULA) having 48 elements spaced at 0.5λ apart.
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Efficient Neural Network-Based Reconstruction of Three-Dimensional Antenna Radiation Patterns From Two-Dimensional Cuts
21 February 2025 Saeed Jan, Yuanzhi Liu and Costas D. Sarris present a novel solution to the classical problem of interpolating three-dimensional antenna radiation patterns from two-dimensional, orthogonal pattern slices. They introduce a neural network model that performs this interpolation with high accuracy across a wide range of patterns, including cases where conventional interpolation methods struggle. This model is beneficial for three-dimensional modeling methods, such as ray-tracing, where a full antenna radiation pattern is needed, whereas only principal plane patterns are available from measurements or data sheets.
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Stability Analysis of the EFIE-IBC Formulation and Regularization via Spatial Filtering
21 February 2025Subuh Pramono, Josaphat Tetuko Sri Sumantyo, Muhammad Hamka Ibrahim, Ayaka Takahashi, Yuki Yoshimoto, Hisato Kashihara, Cahya Edi Santosa, Steven Gao and Koichi Ito proposes a novel antenna substrate that is realized based on low-temperature co-fired ceramic (LTCC) technology using cordierite ceramic (2MgO 2Al2O3 5SiO2). Compared to other existing ceramics, it has an impressive low dielectric constant (ϵr) of 4.674 and a loss tangent (tan δ ) of 0.0723 at 5.3 GHz, which makes it ideal for creating an ultra-wideband (UWB) circularly polarized (CP) array antenna. In addition, cordierite ceramic is suitable for high-temperature environments, its coefficient of linear thermal expansion is about 1.8×10−6 /K (40°C– 800°C), and it expands only 0.1% of its room temperature dimensions even in a 1000°C environment. Through a sputtering process, platinum with a melting point of 1768°C and very good oxidation resistance is used as a conductive material on the cordierite ceramic substrate.
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Temperature-Dependent Over-the-Air Measurements of Total Isotropic Sensitivity for Minimum Uncertainty
20 February 2025 Jiyu Wu, Francesco de Paulis and Yihong Qi suggest a new total isotropic sensitivity (TIS) method that measures TIS at the device’s thermally stable condition, thus redefining TIS not a single value but rather as a function of the transmitter’s power, reducing uncertainty and ambiguity in TIS measurements for wireless and 5G devices. Based on measurement results in this paper, the TIS measurement exhibits a variability of up to 1 dB due to the effects of temperature and transmitting power levels, distinct from the inherent measurement uncertainty of 0.28 dB specified by the standard. A more complex yet accurate measurement procedure is proposed while varying the power level. The proposed method is applied and experimentally verified, demonstrating its usefulness to extract the TIS profile instead of a single value, with a result of the TIS variation as a function of the transmitting power.
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Synthesis of Shaped-Beam Radiation Patterns With Efficient Optimization Algorithm
19 February 2025 Ting Zang and Gaobiao Xiao extend the efficient optimization algorithm for synthesizing shaped beams to the synthesis of radiation patterns of planar current sheets that have different beams and polarizations on the two sides of the source plane. The radiation pattern is described with a real-valued function, which is expressed with the superposition of entire functions and its extrema can be quickly located by searching on a fixed uniform grid in the k-space. By flexibly tuning the positions of the extrema, the ripples in the main beam and the levels of the sidelobes can be effectively controlled.
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Frontiers in Quantum Antennas: Theoretical Foundations, Practical Applications, and Future Outlook
25 February 2025 Abdoalbaset Abohmra, Muhammad Zubair, Masood Ur Rehman, Hasan Abbas, Muhammad A. Imran and Qammer H. Abbasi provide an overview of the theoretical foundations for quantum antennas as open quantum systems, discussing how strong coupling and quantum state manipulation can be harnessed for practical implementations. They then examine groundbreaking advancements in quantum antenna design, including the integration of novel material configurations, such as quantum dot arrays and their interactions with photonic reservoirs. The review explores the unique quantum phenomena exhibited by these antennas, including Rabi oscillations, solitons, and non-reciprocal behavior, which set them apart from classical antennas.