| With the developing of millimeter-wave communication and radar, the demand on millimeter-wave source is more and more strict. And millimeter-wave solid-state oscillators can抰 meet the demands of some systems. It is necessary to develop W- band frequency sources with referenced crystal oscillator. In chapter one, the survey of W-band solid-state frequency sources is given, and the necessity to study frequency sources with high frequency stability and low phase noise is pointed out. In chapter two, based on the theory analysis of two-port second- harmonic Gunn oscillators, W-band phase-locked sources are achieved. In chapter three, in the light of the need of W-band military digital communication system, phase-locked Gunn oscillators with high stability and reliability are developed, which can be modulated directly by digital signal and make the cost of millimeter- wave system lower greatly. In chapter four, the microwave and millimeter-wave multipliers are studied. And in chapter five, W-band multiplier sources with low spurious output and low phase noise are developed. At first, according to the theory analysis on the foundamental and harmonic mode of &unn oscillator, two kinds of two-port second-harmonic Gunn oscillators, one is bias-tuned, and another is varactor-tunable, are presented, and the oscillators have been stabilized in phase-locked loops. The phase noise of the phase-locked oscillator with analogue phase detectors is -77dBc/Hz at 10kHz offset. While the miniaturized phase-locked source in digital phase-locked loops is suitable for military systems. It is analyzed that the relationship of phase shaking between the signals of millimeter-wave and phase-locked intermediate frequency of harmonic mixer in phase-locked ioop. Meanwhile, the inexpedience of substituting the phase noise of internal intermediate frequency for that of phase-locked millimeter-wave oscillator is pointed out. By combining the theory of modulation and phase locking, the feasibility of direct frequency modulation to phase-locked oscillator is analyzed, and W-band phase-locked digital military communication systems with high stability and commercial frequency tracing transceiver systems with low cost are developed by the direct modulation technique. Secondly, the output spectrum of double-balanced mixer using as multiplier is analyzed and it is suitable for even order multiplier. The X4 multiplier with conversion loss 21.2dB in P-band is achieved, which is fit for multiplying the frequency of crystal oscillator. The principle of PIN diode multiplier is described, ?? and the conversion loss of anti-parallel PiN diodes multiplier, which is suitable for odd order multiplier, is calculated by on-off model of PIN diode. As a result, one C- band 5th multiplier is achieved and the conversion loss is 10.6dB. Two multiplier sources, each including one crystal oscillator, one P-band X4 multiplier and one band 5th multiplier, are presented with phase noise -l36dBc/Hz at 10kHz offset. A U-band X4 multiplier, involving one PHEMT doubler and one mixer diode doubler, is achieved with conversion gain 3.5dB. If it is followed by an amplifier, the output power will be up to 40mW, which can meet the demand of fundamental wave injection 2nd harmonic Gunn oscillators, pulsed or continuous wave. Furthermore, the causes of noise and spurs in frequency multiplier chain are pointed out, and the ways to solve the problems are given. It is serious that the influence of flicker noise of com...
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