Based on the design of the 220 GHz sub-harmonic mixer, the vertical conversion structure of the IF transmission waveguide was proposed, and the four-channel mixer integration module was realized, the transverse size of the single channel of the mixer was shorten effectively. It provided a feasible scheme for the multi-channel linear array integration of the terahertz receiver system. In order to further optimize the accuracy of the system model, the three-dimensional semiconductor device modeling calculation was carried out for the Schottky-barrier diode based on TCAD, and the high-frequency electromagnetic wave simulation of the mixer was carried out according to the extracted key characteristic parameters. Through the test of the design scheme, the test results show that when the local frequency is 110 GHz, and the power is 7 dBm, the conversion loss of the mixer is 8.6-13 dB as the RF input is 200-240 GHz, and the conversion loss is 8.6-11.3 dB at 204-238 GHz. When the local frequency is 108 GHz, the driving power only needs 3 dBm. In addition, the 220 GHz receiver system based on the mixer module has a temperature sensitivity of 1.3 K as the integration time is 700 μs.