Wideband Low-Profile Fabry-Perot Cavity Antenna with Metasurface

A novel Fabry-Perot cavity (FPC) antenna with metasurface is presented, which can achieve broad bandwidth and low profile. Traditional FPC antennas, with rectangular microstrip antennas as feeds, have limited impedance bandwidth and struggle to make a compromise in the gain bandwidth and maximum gain value. To obtain wide bandwidth, the FPC antenna proposed in this paper utilizes a feed antenna loaded with parasitic patches. To widen impedance bandwidth and gain bandwidth and reduce the profile, a positive phase gradient partially reflective surface (PRS) and an artificial magnetic conductor (AMC) are located above and below the feed antenna, respectively. The phase property of the PRS and AMC also brings in a more smooth gain value curve. To further increase gain values, four metal reflector plates are located around the proposed antenna. The overall dimension of the antenna is 2.570x2.570x0.2570 7 0 x 2.5 7 0 x 0.25 7 0 (70 7 0 is the free space wavelength at 7.5 GHz). Simulated results show that the resonant cavity antenna proposed in this letter exhibits an impedance bandwidth of 13.3% (7-8 GHz) and a 3 dB gain bandwidth of 14.3% (7.02-8.10 GHz). The maximum gain in the whole operating band is 14.5 dBi. The measured results are in good agreement with the simulated ones.