A 400 GHz Broadband Multi-Branch Waveguide Coupler

Terahertz (THz) technology is a hotspot in current academic research. A 400 GHz broadband Multi-branch waveguide hybrid coupler is designed in this paper. Compared to 5-branch designs, the proposed hybrid consists of 7-branch and has been optimized to a great performance, which increases the operation bandwidth. Based on this model, the performance of the mixer is optimized by HFSS software. The simulation results show that the return loss (S11) and isolation (S23) are better than 20 dB in the frequency range of 350 GHz to 450 GHz, which is nearly 25% relative bandwidth, and the good performance of power splitting can also be seen from the amplitude and phase of S21 and S31.