The Design And The Measurement Of Millimeter-wave Odd Harmonic Mixer

In the development of microwave technology, microwave-test instruments play the roleof the first army. Millimeter‐wave harmonic mixer as a essential microwave device in the front of the microwave-test equipment’s receiver, its performance directly affects the entire microwave-test instrument’s performance good or bad.In this paper, regarding the situation that the research of millimeter-wave harmonic mixeris mainly focused on the even harmonic mixer, we introduce the design of the third harmonicmixer whose operating frequency is in 5mm band and 3mm-band, and conduct an appropriatemethod to comprehensive test the mixer. The paper works from the Working principle of themixer diodes, then discussed the basic principle of the odd harmonic mixer circuits. Weseparately designed the specific structure of the RF input and LO input and IF output, andverify the Good Quality and feasibility by their theoretical calculations and simulation. At last,we complete the mixer’s processing and assembly. Because of the different frequency in theinput and output port, the mixer is difficult to measure. So we also describe all kinds of testingmethods for millimeter-wave mixer at the end of the paper, and with selected the appropriatetest method to test the mixer according to the actual situation, then got a good experimentalresult.The difficulty of the paper is designing a suitable structure of the RF signal input, so that the RF signal can best be added on the mixer diodes, and does not divulge in the form of themicrostrip line’s high-order mode to the other ports. And the design of the fan low-pass filter in the IF input port is also another difficult.The experimental results show that, the conversion loss of the 5mm band harmonic mixer is better than 18dB; the conversion loss of the 3mm band harmonic mixer is betterthan 26dB. That has achieved the desired results and had a great practical value.