The discriminating properties of the synchronized oscillator

The paper describes the response of a synchronized van der Pol oscillator to small-amplitude signals accompanying the synchronizing signal. A simple method of characterization, which involves the response to symmetrical and antisymmetrical sideband pairs of the synchronizing signal, is obtained analytically and is shown to be simple to use. Advantages of this particular characterization of small-signal response are demonstrated by examples, one of which discusses the response of a synchronized oscillator to narrowband noise. A practical oscillator is presented whose behaviour closely approximates to that of the van der Pol oscillator, and which can be used for practical application of the filtering properties of the synchronized oscillator.