Noise-reduction techniques of high-frequency oscillator-high- order multipliers and avalanche-diode-type microwave sources

Results of noise-reduction techniques by injection phase locking to a master oscillator and through the use of high-Q cavities are presented for a class of high- frequency oscillator-high-order multiplier and avalanche-diode oscillator microwave sources. Frequency and amplitude noise spectra are described for two states of oscillation: free-running and injection phase-locked for the video range 300 hertz to 10 MHz off the carrier frequency. At X band, a rms noise deviation less than 0.15 hertz in a 100-hertz bandwidth has been achieved at frequencies greater than 10 kHz off the carrier for the free-running high- frequency oscillator-high-order multiplier source. Corresponding results obtained for a free-running avalanche- diode oscillator was a flat 6-hertz spectrum across the video range 1 kHz to 100 kHz.