| High quality millimeter wave frequency source is the important component in the development of millimeter wave systems and application. Modern millimeter wave systems require millimeter wave frequency source with high frequency stability, low phase noise, and good output power performance, which could provide high quality millimeter wave signals stably for a long time. Avalanche and Gunn oscillators are the traditional way to generate millimeter wave signals, but they have some shortages such as poor phase noise and frequency stability. The complex oscillator circuit and large volume are difficult for millimeter system integration. Frequency multiplication technology is an important way to obtain high quality millimeter wave signals, which could reduce the operation frequency and increase the application frequency range of millimeter wave system. Frequency multiplier could translate the advantages of microwave device into millimeter wave band, such as high frequency stability, low phase noise and modulation character. At present, frequency multiplier is the important way to generate short millimeter wave and submillimeter wave signals.Traditional frequency multiplier chain could obtain high stable and low phase noise signals, but it has complex circuit structure and needs to solve these problems of interstage circuit matching and filtering, which become prominent as the increase of operation frequency. Avalanche device is the important solid power device to generate millimeter wave signals. The nonlinearity of avalanche device has been researched in many aspects and explored for any new application. Taking advantages of the fierce inductive nonlinearity of avalanche breakdown effect, avalanche device could generate rich high order harmonics up to millimeter wave band and has the ability to realize the high order frequency multiplication in millimeter wave band in a signal stage. Avalanche high order multiplier has a simple circuit structure with high frequency multiplication efficiency, which could provide high stable and low phase noise signals with relative high output power comparing with frequency multiplier chains. In addition, avalanche device could operate in the whole millimeter wave band from 30GHz to 300GHz stably with good power character. So avalanche high order frequency multiplication technology is very suitable to explore the new short millimeter wave frequency band and be applied into high performance millimeter wave and submillimeter wave systems.The work in this dissertation is aimed to solve these basic problems of the mechanism of avalanche high order multiplication, the nonlinear model of avalanche high order multiplication and the characters of avalanche high order multiplication theoretically. Based on analyzing these characters of avalanche carriers generation, increase and transportation process, the interactions between fundamental frequency and harmonics, the energy conversion between harmonics, the operation of avalanche high order frequency multiplication has been interpreted and defined explicitly. According to the physical mechanism of avalanche device, the nonlinear model of avalanche high order frequency multiplication is analyzed and built, which provide a simulation platform to analyze the high order harmonics character of avalanche device. Based on the nonlinear model, the avalanche high order frequency multipliers are analyzed, manufactured and researched in experiment, which demonstrate the rich high order harmonics character of avalanche device and the correction of nonlinear model. The work in this dissertation solve the problem of direct high order frequency multiplication in millimeter wave band by nonlinear solid device and provide a new technology to obtain high quality millimeter wave signals. The major achievements are listed as the followings:1. The nonlinear character of avalanche device in high order frequency multiplication mode is researched and analyzed systematically. The definition of avalanche high order frequency multiplication mode is interpreted and the equal circuit model of this new operation mode is also presented.2. For the first time, the nonlinear model of avalanche device in high order frequency mode is researched and built. And a simulated circuit model has been set up to analyze and predict the high order harmonics character of avalanche device, which has been successfully applied to the analysis and design of W band microstrip integrated avalanche high order multiplier.3. Based on the oscillator circuit of cap structure, the new circuit of radial resonant cavity with cap structure is presented. The electromagnetic character and equal circuit model of radial resonant cavity with cap structure are analyzed. Utilizing the accurate electromagnetic simulation tools, the avalanche high order frequency multiplier is designed and manufactured, which has good performance in experiment.4. For the first time, the D band avalanche high order frequency multiplier is researched and manufactured by domestic avalanche device. Effective output power above 1mw has been obtained at the output frequency of 120GHz.5. For the first time, the W band planar integrated avalanche high order multiplier is realized. Two kinds of microstrip integrated and coplanar waveguide integrated avalanche high order multiplier are analyzed, simulated and manufactured. Good performance has been achieved, which indicate the development of avalanche high order multiplier with low volume and high integration.
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