Novel 1-Bit Beam-Scanning Reflectarray With Switchable Linear, Left-Handed, or Right-Handed Circular Polarization

• Published in: IEEE transactions on antennas and propagation Vol. 71; no. 2; pp. 1548 - 1556
• Main Authors: Hu, Jianjia, Chi, Pei-Ling, Yang, Tao
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.02.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Apertures; Beam scanning; Circular polarization; Feeds; Linear polarization; p-i-n diode; P-i-n diodes; Phased arrays; PIN diodes; Polarization; Quantization (signal); reconfigurable; reflectarray; Reflection; right-/left-handed (RH/LH) circular polarization; Scanning; switchable polarization; Switches; Switching; Unit cell
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2022.3226146

This article proposes a novel reconfigurable reflectarray (RRA) with 1 bit beam scanning and switchable linear, left-handed (LH) circular, or right-handed (RH) circular polarization. To realize a multipolarization switchable RRA fed by a horn of arbitrarily fixed polarization, the unit cell's reflection phases in <inline-formula> <tex-math notation="LaTeX">x </tex-math></inline-formula>- and <inline-formula> <tex-math notation="LaTeX">y </tex-math></inline-formula>-directions are independently controlled to meet the required differential phase in each state. Explicit reflection-phase relation will be given for switching from one polarization to another while fulfilling the 1 bit beam scanning. A <inline-formula> <tex-math notation="LaTeX">10\times 10 </tex-math></inline-formula> RRA was prototyped with each unit cell using only two p-i-n diodes to implement dual functions. The fabricated RRA was tested and it can experimentally demonstrate 2-D beam scanning and polarization switching among 45°/135° linear polarization and LH/RH circular polarization. In circular polarization, the measured peak gain, aperture efficiency, and 1 dB gain bandwidth are 17.2 dBic, 26%, and 8.2%, respectively. In linear polarization, the measured cross-polarization discrimination (XPD) of greater than 15 dB, peak gain of 16.8 dBi, aperture efficiency of 23.9%, and 1 dB bandwidth of 5.3% are obtained.