Printed RGW cascaded 3-dB coupler with enhanced performance for millimeter wave applications

This paper introduces a printed ridge gap waveguide (PRGW) hybrid coupler for millimeter wave applications in the Ka-band. The coupler achieves 33% bandwidth with more than 15 dB isolation and return losses. A small amplitude and phase imbalances of less than 0.3 dB and 3 degrees, are obtained, respectively by applying a combined design of two individual 8.34 dB couplers in cascaded manner. Simulation results are compared with other works from literature assisting the improved performance of the proposed design.