Oscillator phase noise models

Harmonic signal sources can be found in almost all modern electronic systems. These generators serve e.g. as clock sources for timing or they can be used for synchronization. In all cases, strict claims are posed on a quality of the output signal, especially the stability, the purity and the signal level. This article deals with the modeling of the oscillator phase noise. The general definition of the phase noise is explained and the single sideband phase noise course is shown. Various oscillator phase noise models are introduced. Each model is described and its parameters affecting the phase noise are studied. The phase noise impact to the precise oscillator design is mentioned.