Multilayer Slot-Coupler Based On Integrated Substrate Gap Waveguide

A multilayer slot-coupler based on integrated substrate gap waveguide (ISGW) is proposed. The proposed coupler is consisted of two ISGWs, which are broadside coupled through fish bone shape slot in the common ground. Simulation shows that the proposed coupler can have either -3±1 dB tight coupling from 23.07 to 28.55 GHz or -6±1 dB tight coupling from 24.48 to 30.73 GHz. Moreover, the phases between through and coupled port differ by 90°. The return loss and isolation are less than -20 dB over the operating frequency band.