Design of V-band Diplexer Based on Electro-magnetic Band Gap Structure

In this paper, a V-band diplexer with high isolation and short branches characteristic is introduced. A bandpass filter (BPF) is connected to the common port of the diplexer, and stopband filters (BSFs) based on electromagnetic band gap (EBG) structure are inserted into the branches to achieve the characteristics of high isolation and short branches of the diplexer. The isolation and passband of the diplexer can be changed by adjusting the dimensions of EBG structure. The simulation results show that the maximum insertion losses are 1.15 dB and 1.19 dB at the center frequency of 60 GHz and 65 GHz, the relative bandwidth are 5 % and 4.6 %, respectively. And the isolation is better than 37 dB, which has good electrical performance.