A tri-band Fabry-Perot cavity for antenna gain enhancement

This paper presents a tri-band Fabry-Perot cavity, which can be applied to design tri-band Fabry-Perot resonator antennas. The cavity is composed of a PEC ground plane and a thin partially reflective surface (PRS). On the proposed PRS, two distinct resonant frequencies are appropriately designed so that the Fabry-Perot cavity is able to resonate at three frequency bands. This can be utilized to enhance the directivity and gain of small antennas at three distinct bands. Simulations confirm the design principle.