Wideband cavity-backed slot subarray with gap waveguide feed-network for D-band applications

A simple and wideband subarray for D-band applications is presented in this paper. The proposed multilayer subarray consists of 2 × 2 cavity-backed slot subarray fed by a ridge gap waveguide transmission line. The simulated results show that the proposed subarray has a relative impedance bandwidth of 22.5% with input reflection coefficient better than -10 dB over the 126-158 GHz frequency band. An array antenna consisting of 8 × 8 slots is designed with the proposed subarray. The simulation results of the proposed subarray and antenna are presented.