Millimeter-wave Mixer

This thesis overall views the historical development, future trend, active devices. sensitivity definitions and configurations of microwave and millimeter mixers, and then discuss several kinds of mixers and mixer diodes. The theory of mixer diode -anti-diodes, harmonic mixed frequency and harmonic balance analysis is given. Based on those and the practical needs of some projects, The thesis mainly focuses on two different kind millimeter mixers: a Ka band mixer and an EHF band mixer.In the EHF band mixer design the crossbar mixer type was used. Based on the results of the theory analysis and computer simulation of suspended stripline low pass filter, band pass filter, the transition from waveguide to finline and the transition from waveguide to suspended stripline, the structure design and manufacture were made. The measured results match the requirement.Different from the traditional mixers used in the domestic communications satellites, the sub-harmonic balance mixer type was used in the Ka-Band mixer design. This will decrease the frequency of the local oscillator and simplify the local oscillator design, and increase the performance and the reliability of the mixer.In this article, the input diplexer method was firstly presented in the mixer design. With this method the Ka-band mixer was designed, simulated, manufactured and tested. The measured results are much better than the product of the other research institute.