Dual Circularly-Polarized Fabry-Perot Antenna Using Single-Layer Self-Polarizing PRS

This letter presents a dual circularly-polarized (CP) Fabry-Perot antenna (FPA) using a novel self-polarizing partially reflecting surface (PRS). Its source element is a double differential-fed patch for generating a dual linearly-polarized (LP) radiation. The PRS is an array of double truncated-corner patches with orthogonal slots and shorted pins, which is built on a single-layered substrate to not only ensure high reflectivity for a high-gain FPA but also convert the dual-LP waves to dual-CP waves. A prototype operating at 5.8 GHz has been fabricated and measured. The proposed FPA with overall size of 2.4\lambda _{{0}}\times 2.4\lambda _{{0}}\times 0.58\lambda _{{0}} at 5.6 GHz achieves a 10-dB return loss bandwidth (BW) of 11.3% (5.50-6.16 GHz), an isolation \ge 17 dB, a 3-dB axial-ratio BW of 8.6% (5.6-6.1 GHz), and a 3-dB gain BW of 13.8% (5.4-6.2 GHz) with the peak gain of 13.7 dBi.