Enhanced Wideband Circularly Polarized Fabry-Perot Antenna with Dual-layer Partially Reflective Surface for X-band Satellite Communications

This paper presented a dual-layer partially reflective surface (PRS) to increase bandwidth of a circularly polarized (CP) Fabry-Perot (FP) cavity antenna for X-band satellite communications. The proposed PRS consisted of two dielectric substrates with metallic square ring patterns on upper sides, separated by an air thickness λ_o/11 (λ_o is the wavelength in the free space) at 9.3 GHz. By optimizing ring width and layer air thickness, the PRS reflection phase was designed to achieve wideband performance. An antenna prototype with overall size of 2.5λ_o × 2.5λ_o × 0.7λ_o has been simulated. Consequently, the proposed CPFA antenna provides an 8.89 dBi high gain with 87% total efficiency. Moreover, it achieves an AR lowered by 1 dB.