Fabry-Perot Resonant Cavity Antenna with Tunable Superstrate for Beam Steering Millimeter-Wave Applications

This work presents a novel beam-steerable microstrip millimeter-wave antenna. The antenna is constructed using a single-layer metamaterial superstrate, arranged on top of a wideband patch antenna in the form of a Fabry-Perot resonant cavity (FPRC). The superstrate comprises dual-array of square patches; each array consists of 9X3 square unit cells. The dual-array unit cells are placed on both sides of a parasitic patch printed on the top layer of the superstrate. By varying the electrical length of the unit cells using electronic switches controlled with DC bias, the proposed antenna achieves beam steering at -20 degrees and +20 degrees. Other beam directions can be achieved by changing the switching schemes of the electronic switches. The proposed FPRC based on a single patch antenna exhibits an acceptable peak gain that ranges from 7 to 9.7 dB throughout the whole operating impedance bandwidth from 29 GHz to 35.3 GHz and for different switching schemes.