Design of 340GHz Subharmonic Mixer for Communication Application

In this paper, a 340GHz subharmonic mixer based on a planar Schottky barrier diode is designed. The mixer circuit is fabricated on a 0.05mm thick quartz, substrate adopting suspended microstrip structure and using an anti-parallel diode pair. The HFSS software is used to simulate the passive part of the circuit, including the RF transition structure, LO-IF duplex structure. Then import them into the ADS software to perform nonlinear co-simulation together with the diode pair. After optimization, under the condition of the stable LO frequency, the conversion loss is less than 10 dB in the frequency range of 305-380 GHz, and the bandwidth with a conversion loss of 8 dB or less reaches 60 GHz. Then, the tolerance analysis is further carried out, the test proves that the mixer has very good tolerance to the error in the assembly process.