Design of a 600GHz Broadband 3dB Hybrid Coupler

A E plane of 3 dB rectangular waveguide directional coupler with different lengths of branch waveguide and introducing two waveguide-height discontinuity sections placed symmetrically in the main wave-guide operating at the center frequency of 600 GHz is presented. This kind of structure introduces a controllable ripple in the operational band and allows low amplitude imbalance over a wide operational band. The amplitude imbalance is less than 0.4dB, and the bandwidth can reach 24.5%.