What is oscillator jitter?

Jitter is a method of describing the stability of an oscillator in the Time Domain. It combines all the noise sources together and shows their effect with respect to time. Jitter measures the variations of signal period in the time domain, describing how far the signal period has wandered from its ideal value.

What is clock wander?

While jitter is normally measured with reference to a clock extracted from the data signal, wander is measured against an external reference clock . The fundamental measurement is of Time Interval Error (TIE). This represents the time deviation of the clock signal under test relative to the reference source.

What is wander in networking?

Wander is slow phase variation over time. The accumulated phase changes in the node clock result in a frequency offset, which ideally should be zero over very long observation periods; at least, this is true for a node clock that is properly locked to the nearest higher level in the hierarchy.

What is jitter tolerance?

Furthermore, testing of device performance for jitter tolerance often involves the injection of jitter into electronic components with specialized test equipment. Jitter is a measure of short-term, significant variations of a digital signal from its ideal position in time.

How does a van der Pol oscillator work?

The forced, or driven, Van der Pol oscillator takes the ‘original’ function and adds a driving function A sin ( ωt) to give a differential equation of the form: where A is the amplitude, or displacement, of the wave function and ω is its angular velocity . Electrical circuit involving a triode, resulting in a forced Van der Pol oscillator.

What are the characteristics of a good oscillator?

Some oscillators have good short term characteristics but show more long term drift and random walk (crystal oscillators, or XOs for instance) and others have more noise in the short term but better long term characteristics (Cesium or GPS for instance).

What causes a variation in the period of an oscillator?

This variation in oscillator period is called jitter. Local temperature effects cause the period of a ring oscillator to wander above and below the long-term average period.

What makes a clock a disciplined oscillator?

A clock is a “disciplined” oscillator Oscillator: The discrete-time signal {w(n,k) = [x(n+k)-x(n)]} is the “Time Interval Error” (TIE) and is the basis for quantifying the “frequency” performance of the clock (relative to reference); first difference removes any constant time (phase) error.