A single layer high gain Fabry-Perot cavity antenna
A single layer and single feed high gain Fabry-Perot cavity type antenna is presented in this paper. The antenna is designed to operate at around 22 GHz so that it can be used for K-band applications. An open-ended leaky-wave slit dipole fed by a coplanar waveguide is printed on one side of the substrate whereas a frequency selective surface made of a circular hole array is defined on another side of the substrate; thus forms a substrate-integrated Fabry-Perot cavity. The simulation results show that the proposed feeding structure exhibits a wide impedance bandwidth characteristic and effectively excites the resonance of the substrate cavity simultaneously. After optimization, the antenna is capable of having an impedance bandwidth (VSWR≤2) of about 8%, a maximum gain of about 14 dBi, and a 3-dB gain bandwidth of approximately 1.5% at a resonance frequency of 21.7 GHz.