A Design of Extremely Wideband Fabry-Perot Cavity Antenna

This paper presents an extremely wideband Fabry-Perot cavity antenna (FPCA). By using gradient permittivity partially reflection surface (PRS), the 3-dB gain bandwidth is improved dramatically. To achieve effective gradient permittivity, a single-slab superstrate with different size holes is studied, showing that the effective gradient permittivity decreases with the dimension of holes increase. The gain performance with different gradient steps of permittivity is analyzed and optimized. A Ku-band FPCA is simulated. The simulated results demonstrate that the proposed design has high efficacy, which can achieve maximum gain of 17.3dBi with 3-dB gain bandwidth of 58%.