Noise and nonlinear distortions of signals in fiber-optic systems (review)

An analysis is made of the sources of noise in fiber-optic systems. Estimates are obtained of the levels of intrinsic noise in various types of semiconductor injection lasers and the main causes of an increase in the noise level and of the appearance of nonlinear distortions in signals are discussed for systems of this kind. Some ways of reducing noise in fiber-optic systems are considered.