Thin Conformal Directive Fabry–Pérot Cavity Antenna

A compensated-phase partially reflective surface (PRS) is proposed in this letter. It is used together with a metallic ground plane to form a low-profile Fabry-Pérot (FP) cavity antenna conformed on a cylindrical surface. A microstrip patch antenna is embedded inside the cavity to act as the primary feed. To validate the proposed PRS, an antenna is designed to operate at the 5.7-GHz Wi-Fi frequency. The subwavelength FP cavity with a fixed overall thickness of λ
₀
/10 (where λ
₀
is the free-space operating wavelength) is fabricated and measured. The impact of compensating the PRS phase is analyzed.