Wideband, Dual-Polarized Patch Antenna Array Fed by Novel, Differentially Fed Structure

• Published in: Electronics (Basel) Vol. 13; no. 7; p. 1382
• Main Authors: Ou, Naiming, Wu, Xian, Xu, Kaijiang, Sun, Fukun, Yu, Tongfei, Luan, Yuchen
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.04.2024
• Subjects: Antenna arrays; Antennas; Antennas (Electronics); Bandwidths; Broadband; Cables; Circuit boards; Circular polarization; Coaxial cables; Design; Dual polarization (waves); Horizontal polarization; Musical performances; Patch antennas; Printed circuits; Radiation; Substrates; Vertical polarization
• ISSN: 2079-9292; 2079-9292
• DOI: 10.3390/electronics13071382

In this article, a 1 × 4 wideband, dual-polarized patch antenna array fed by a novel, differentially fed structure is proposed. The differentially fed structure of the antenna was realized by a parallel line structure that was printed on a PCB and connected with the inner and outer conductors of a coaxial cable. This method elaborately solved the problem of the narrow bandwidth of conventional microstrip differential feeding. By using a relatively thick air substrate (thickness = 0.19 λ0), stacked patches, a coupling feeding structure, and a differential feeding structure with the novel design, the element of the patch antenna array introduced below operated from 0.415 GHz to 0.707 GHz (achieving the 52.0% bandwidth) with a VSWR < 2.0, yielding a high port isolation less than −28 dB. For the array, an active VSWR less than 2.0 was also obtained with a port isolation of less than −25 dB, ranging from 0.405 GHz to 0.696 GHz. In the desired bandwidth, the array had an azimuth 3 dB beamwidth of about 19° for both horizontal polarization and vertical polarization. The antenna array also had good performance in scanning (stable gain and 3 dB beamwidth) and circular polarization (a 3 dB axial ratio bandwidth better than 54.5%).