An Rectangular Diplexer Based on Substrate Integrated Waveguide

In paper, substrate integrated waveguide (SIW) method is used to design a diplexer. The diplexer adopts the structure of SIW to design two band-pass filters and T-junctions. And it is connected according to the structure of this paper. The simulation results show that the insertion loss is −2dB and the return loss is −20dB, and the sample of the diplexer is obtained through certain processing. The test results show that the isolation degree is −50dB, verifying the rationality of the design.