Recent Articles
-
Mechanically Scanned Leaky-Wave Pillbox K-Band Antenna With Dual Radiating Layers Using Variable Permittivity Substrate and Nonuniform Patches
09 May 2025Ahmed Jasim, Mahdi Moosazadeh, Christophe Fumeaux and Amin Abbosh present a low-profile, high-gain leaky-wave pillbox K-band antenna with mechanical beam scanning. The antenna consists of three layers: one feeding network layer and two radiating layers. A substrate-integrated waveguide wide-angle H-plane horn feed is connected to a one-dimensional reflector using vias rows, forming a closed pillbox reflector to prevent parasitic wave leakage. A simple coaxial feeding port is used to reduce the antenna’s complexity and cost.
-
Efficient Calculation of Propagation Coefficients in Anisotropic Media Through Transfer Matrix Method Based on Eigenvalue Analysis
08 May 2025 Jiuyang Fan, Zhixiang Huang, Xiaoli Feng and Yuxian Zhang adopt eigenvalue (EV-) analysis to implement the transfer matrix method (TMM), abbreviated as EV-TMM, enabling the accurate capture of propagation coefficients with different polarizations under the inhomogeneous multi-layer background. When the plane waves carrying electromagnetic information enters an anisotropic medium from air, it will excite four beams with different energies and propagation directions in the medium.
-
Metrology of Multicarrier-Based Delay-Doppler Channel Sounding for sub-THz Frequencies
02 May 2025 Jonas Gedschold, Diego Dupleich, Sebastian Semper, Michael Döbereiner, Alexander Ebert, Giovanni Del Galdo and Reiner S. Thomä propose and discuss an over-the-air artifact allowing a joint verification of delay and Doppler parameters in a multipath scenario. The evaluations of exemplary sub-THz measurements with a multicarrier-based sounder highlight the strong interplay between sounder hardware and estimation algorithms, especially when coping with the mutual interference of parameters from multiple propagation paths. Hence, a metrological assessment always requires considering the full processing pipeline from the unprocessed measurements up to the extracted propagation parameters.
-
A Wideband and Low-SAR Antenna Design at 2.45 GHz for Biomedical Applications
30 April 2025 Sami Ullah Khan, Muhammad Aamir, Muhammad Abbas, Uzman Ali, Usman Ali and Toni Björninen design a miniaturized implantable antenna for biomedical applications operating within the industrial, scientific, and medical band (ISM, 2.4–2.48 GHz). The proposed implantable antenna has a compact size of 5.5 × 5.5 × 0.64 mm and is manufactured using a biocompatible substrate, Roger RO3010 with permittivity of εr=10.2 and losstangentof tan(δ)=0.0022. To enhance safety, a superstrate and a silicon coating around the antenna are employed to isolate the antenna from the surrounding biological tissues. The simulation software from the HFSS and CST studio suite was utilized to simulate and optimize the proposed implantable antenna, followed by fabrication and testing.
-
A Single-Bit Reconfigurable Folded Reflectarray/Transmitarray Antenna
30 April 2025 Manting Wang, Jiachen Du, Dashuang Liao and Chi Hou Chan introduce a novel receiving-transmitting (RA-TA) metasurface unit cell for folded transmitarray/reflectarray antennas (FTAs/FRAs). The unit cell comprises two substrates with an air gap to ensure optimal transmission and integration of PIN diodes. Polarizer grids are employed for selecting desired polarization while each grid metal provides DC bias independently to a single unit cell with two PIN diodes surface-mounted and their orientation perpendicular to each other, i.e., along 1450, respectively, enabling 1-bit phase compensation and polarization conversion. Thus, the proposed antenna achieves 1-bit reconfigurability and maintains polarization consistency with the feeding source.
-
Multipolar On-Resonance Interference For Super-Gain Electrically Small Dielectric Resonator Antenna (Esdra) Design
25 April 2025 Ahmed Abdelraheem, Duhan Eroglu, Karim Seddik and Dimitrios Peroulis propose a Mie scattering-based approach, employing multipolar decomposition to tailor the dielectric resonator multipoles. The poor radiation efficiency associated with small size (ka < 1) is remedied by on-resonance multipole overlapping, subsequently increasing aperture efficiency and gain. Two simple single-ported ESDRAs with the smallest reported ka of 0.99 and 0.62 are presented. Driven by a deeply subwavelength, poorly radiating elementary electric dipole, high-efficiency ESDRAs are obtained.
-
Dielectric EBG Leaky-Wave Antenna: Design and Experimental Validation
25 April 2025 Ludovica Tognolatti, Paolo Baccarelli, Cristina Ponti, Silvio Ceccuzzi, Vakhtang Jandieri and Giuseppe Schettini propose a novel Electromagnetic Band-Gap (EBG) leaky-wave antenna (LWA) operating in the K-band with enhanced directivity at broadside. A rigorous method that combines the analysis of the band diagrams of Bloch waves propagating within two-dimensional (2-D) EBG structures and the properties of bound and leaky modes in transversely open lattice waveguides is used to design the antenna. For the first time, a three-dimensional (3-D) realistic configuration of the EBG structure is designed, manufactured, and measured in the K-band.
-
Electromagnetic Analysis of Radio Propagation in Fresh Water and Measurement by Axial Mode Helical Antenna at 433 MHz
21 April 2025 Afiza Nur Jaafar, Hajar Ja’Afar, Yoshihide Yamada, Nurul Huda Abd Rahman, Naobumi Michishita, Norsiha Zainudin, Fatemeh Sedeghikia, Rina Abdullah clarify antenna design and electrical performance in underwater use. Then, analysis of electric field distributions underwater and radio link design equation are clarified using electromagnetic simulations. A frequency of 433 MHz is selected from the ISM band. For a high gain antenna, an axial mode helical antenna is selected because of structural simplicity and adaptability of gain change by changing number of turns. The antenna is placed in a capsule to prevent direct contact with surrounding water. In order to achieve effective antenna gain, it is shown to fill the capsule with distilled water of zero conductivity.
-
Additive Manufacturing of Antennas and RF Components for SATCOM: A Review
18 April 2025 Hafsa Talpur, Ulan Myrzakhan, Juan Andres Vasquez-Peralvo, Shuai Zhang and Symeon Chatzinotas provide a review of current state-of-the-art AM printed antennas and RF components incorporating different additive manufacturing (AM) techniques and materials to obtain specific design characteristics such as high gain, wide bandwidth, beamforming, and better power handling capacity, particularly for Ku, K, and Ka-band satellite communication (SATCOM).
-
Investigation of Orthogonal Modes in a Periodic Structure and Application to Two-Separate Beams Steering Within the Same Frequency Band
18 April 2025 Yunhao Fu, King Yuk Chan, and Rodica Ramer investigates orthogonal modes and their space harmonics in a dielectric-filled rectangular waveguide (RWG) leaky-wave structure. The dispersion analysis on orthogonal modes in periodic structures aims to determine the feasibility of two individual beams steering in different spatial regions. The Brillouin diagrams explain the basic principles of the constructed leaky-wave structure; a feeding network is developed for mode excitation. The proposed two-port prototype utilizes standard printed circuit board (PCB) and 3D printing techniques, and the dispersion properties reveal an agreement between measurements and simulations. From 19.6 to 22.2 GHz, the measurements showcase two separate beams steered for each port excitation.
