Design of a 300GHz Cross-coupled Waveguide Filter

In this paper, a 300GHz band-pass filter is designed with cross-coupled structure and waveguide. The initial waveguide is given by the synthesis of the coupled matrix, then the design of the filter is realized by optimizing the electromagnetic model in HFSS. Simulation results show that the filter’s bandwidth is 7.5 GHz, the return loss is less than 22dB, and the insertion loss in the band is less than 1.5dB. The two transmission zeros are located at 288GHz and 310GHz, which makes the S 21 curve steeper near the passband and improve the filter’s out-of-band rejection.