Results of phase and injection locking of an orotron oscillator

Experiments are described which result in phase and injection locking of a 60-GHz orotron oscillator in pulsed and CW modes. The measured phase-locked phase noise results obtained in CW mode were -85, -95, and -105 dBc/Hz at 1, 10, and 100 kHz separation from the carrier, respectively. The null depths and asymmetry of the first maxima of the pulsed spectrum for this source were 35 dB and 2 dB (difference between power levels of first maxima), respectively, operating with a pulse width of 15 μs. At 3 μs, these quantities become 25 dB and 1 dB, respectively. The orotron was observed to injection lock in pulsed mode with an input signal 22 dB below the output power level