Injection locking

Injection locking and pulling effects are observed in numerous types of physical systems, however the terms are most often associated with electronic oscillators or laser resonators.

Injection locking has been used in beneficial and clever ways in the design of early television sets and oscilloscopes, allowing the equipment to be synchronized to external signals at a relatively low cost.

However, injection locking and pulling, when unintended, can degrade the performance of phase-locked loops and RF integrated circuits.

Modern researchers have confirmed his suspicion that the pendulums were coupled by tiny back-and-forth vibrations in the wooden beam.

It has been employed for frequency division[2] or jitter reduction in PLL, with the input of pure sinusoidal waveform.

Entrainment occurs because small amounts of energy are transferred between the two systems when they are out of phase in such a way as to produce negative feedback.

[11] The use of the word entrainment in the modern physics literature most often refers to the movement of one fluid, or collection of particulates, by another.

The use of the word to refer to mode locking of non-linear coupled oscillators appears mostly after about 1980, and remains relatively rare in comparison.

This chaotic artifact (entrainment) is observed when correlated input signals are presented to an adaptive feedback canceller.

Phase-Locked Loop Circuit Design, Prentice Hall, ISBN 0-13-662743-9, pages 95–105 * Lee, Thomas H. 2004.