Keysight Technologies, Inc.
Low phase noise oscillator using negative feedback

Abstract:

An oscillator includes a resonator and a first loop circuit. The first loop circuit includes an amplifier and a first coupler. That first loop circuit is electrically coupled to the resonator. The oscillator is configured to produce negative feedback for the amplifier in a cavity mode relative to short circuit terminations or open circuit terminations of a cavity modelling the oscillator at frequencies offset from a carrier frequency. The oscillator has a loss of less than 4.00 dB for a bidirectional trip through the cavity at the frequencies offset from the carrier frequency.