Small-signal and large-signal noise analyses of nonlinear circuits in frequency domain

The problems of a noise analysis of the nonlinear circuits for small and large signal's levels are surveyed. It's shown, that the known method of the correlation analysis of the linear circuits requiring knowledge of correlation matrices of all elements of the circuit can be implemented at a level of primary sources of noises of each circuit element. Such approach essentially simplifies a mathematical and algorithmic realization of the analysis, dilating its possibilities on all devices, for which the equivalent noise circuits are known, but the correlation noise matrix is not obtained. The nonlinear analysis of the nonlinear circuits noises is discussed. The method of nonlinear noise analysis based on canonical decomposition of spectral densities of circuit's noise sources is advanced. The method, contrary to LSSS method, widely used in the programs of the analysis nonlinear of MW&RF circuits, allows effectively to parse both poorly rustling circuits, and circuit with a very high noise level, when the nonlinearity of the circuit in relation to noise cannot be neglected.