Colpitts oscillator: A new criterion of energy saving for high performance signal sources

This paper describes a new criterion for designing power-efficient signal sources for the application in frequency generating and frequency controlled electronic circuits and systems. The novel approach is based on PI (phase-injection) and MC (mode-coupling) techniques for improving the DC-RF conversion efficiency (η) without degrading the PN (phase noise) and FOM (figure-of-merit) performances. Conventionally, Colpitts oscillator topology is known for low PN signal sources. With a systematic approach to the Colpitts oscillator this paper provides information for an optimized design and the resulting phase noise performances for both low quality factor (example: planar transmission line resonator based energy storing tank circuit) and high quality factor (example: crystal resonator based energy storing devices) based frequency generating sources.