The Design Of Millimeter-wave Mixer

The research about millimeter wave mixer always is a hot subject since many years. With basic design theory of millimeter wave mixer and harmonic balance analysis method, the design of the millimeter wave mixer is explored in this thesis and A Ka band mixer and Ka band up-converter assembly was developed. The Ka band mixer was designed with a low frequency LO. In addition, it used a diode that was used in design of sub-millimeter wave harmonic mixer as mixing element to validate the feasibility about design of sub-millimeter wave harmonic mixer.By measuring the Ka band mixer, the results of the test show that this mixer has the better conversion loss, isolation and VSWR between all ports. By measuring the Ka band up-converter assembly, the results of the test show that this assembly has the better conversion loss, the higher rejection ratio to LO, inter-modulation signals and spurious signals, the better amplitude-frequency characteristic and the smaller geometry size. The electric indexes of Ka band mixer and Ka band up-converter satisfy the user's requirements.At present, the research about sub-millimeter wave harmonic mixing is still very rare in domestic. Meanwhile, because millimeter wave technique has been mature and sub-millimeter wave technique will be a new research domain, the research about design of sub-millimeter wave harmonic mixer will be developed in this thesis. By using co-simulation of ADS and HFSS software, the design of 360GHz second harmonic mixer using microstrip line as basic transmission line was performed. This mixer used Fluorphlogopite Mica with high dielectric constant and low-loss as the substrate material and used Schottky diode with high cut-off frequency as mixing element. The results of simulation show that sub-millimeter wave harmonic mixer using Schottky diode pairs as mixing element has the better conversion loss and isolation.