Work

A Bidirectional Right-Hand Circularly Polarized Endfire Antenna Array for 5G Tunnel Communications

Year: 2026

Type: article

Abstract: For 5G tunnel communications, antennas often face critical challenges arising from severe path loss and multipath fading in confined environments, as well as polarization mismatch under dynamic propagation conditions. This paper proposes a 3.5-GHz circularly polarized (CP) endfire antenna array with bidirectional right-hand CP radiation, featuring high gain, low profile, and compact configuration. The array is implemented on a single-layer F4B substrate and integrates eight pairs of electric and magnetic dipoles to synthesize orthogonal linear field components required for CP radiation. By applying the extended method of maximum power transmission efficiency, constraints on the amplitude and phase are introduced to maximize the CP gain in the endfire direction. A 16-element linear array prototype is fabricated and tested for validation. Measurement results show that the proposed array achieves a bidirectional right-hand CP endfire gain exceeding 12.2 dBic, an impedance bandwidth from 3.1 to 3.78 GHz, and a 3 dB axial ratio bandwidth of 19.5%, demonstrating its suitability for 5G tunnel communication applications.

Source: Electronics

DOI: 10.3390/electronics15020374

Authors: Wenbo Li, Haitao Lu, Peng Xu, Xiao Cai

Institutions: Nanjing University of Information Science and Technology, Jiangsu Maritime Institute, State Key Laboratory of Millimeter Waves, Southeast University

Language: English

Topic: Antenna Design and Analysis

Subfield: Aerospace Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $2,896