Microwave Oscillators

Abstract

Microwave applications such as communications and radars require stable, efficient, and low‐noise microwave oscillators. For this purpose, microwave oscillators are characterized by their frequency of operation, output power, phase noise, long‐term stability, and DC‐to‐RF efficiency. This article discusses the small‐signal and large‐signal designs of microwave oscillators, based on the negative‐resistance model. Also, the injection‐locking phenomenon is introduced and analyzed employing the equivalent‐circuit model of injection‐locked oscillators. The phase noise of microwave oscillators is explained using Leeson's model. Several practical oscillators are examined. Finally, the state‐of‐the art result for various microwave integrated oscillators is presented.