Wideband Quad-Polarization-Reconfigurable Bidirectional Antenna With a Simple Wideband Switchable Feeding Network

• Published in: IEEE antennas and wireless propagation letters 2023-06, Vol.22 (6), p.1-5
• Main Authors: Liu, Min, Zhai, Zhen Jun, Lin, Feng, Sun, Hou Jun
• Format: Article
• Language: English
• Subjects: Antennas; Baluns; Bidirectional antenna; Broadband; Broadband antennas; Circular polarization; Dual polarization (waves); Fractals; Linear polarization; Monopole antennas; PIN diodes; quad-polarization antenna; reconfigurable antenna; Reconfiguration; Substrates; switchable feeding network; Switches; Wideband
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2023.3241987

This paper presents a wideband quad-polarization-reconfigurable bidirectional antenna using a simple wideband switchable feeding network. By cutting a symmetrical fractal slot on the ground, a wideband dual-polarized differential bidirectional circular monopole antenna with high isolation is realized. To achieve reconfigurable quad-polarization diversity, the bidirectional circular monopole antenna is fed by a wideband switchable feeding network, which provides four output states by only using six PIN diodes. For verification, a prototype operating at 1.85 GHz is designed and fabricated. For the two linear polarization (LP) states, the measured 10-dB bandwidths are 28.4% and 25.3%, while the measured peak gains are 4.2 dBi and 3.1 dBi, respectively. For the two circular polarization (CP) states, the measured bandwidths with 10-dB return loss and 3-dB axial ratio (AR) are 26.3% and 17.4%, respectively. The measured peak gains are 2.8 dBi and 2.4 dBi, respectively.