A 60 GHz-Band 4×4 Butler Matrix Based on Ridge Gap Waveguide

Paper in proceeding, 2022

A 4×4 butler matrix based on ridge gap waveguide (RGW) is presented for 60 GHz applications. The proposed Butler matrix consists of four ridge gap waveguide-based couplers, a cross-over and four phase shifters. The simulation results show that return loss and isolation of the Butler matrix are better than 15 dB. Also, power-split imbalance of ±1 dB and phase error of ±7° is achieved over the bandwidth of 59-61 GHz. This wideband Butler matrix design can play a great role while designing wideband beam forming feed network, comparator network etc. for the antenna arrays at millimeter-wave frequencies.