Characterization of Noise Performance of Pumped Nonlinear Systems

An attempt has been made to define exchangeable amplitude and phase noise powers for pumped nonlinear systems. The idea of cascading of linear lossless networks has been introduced for this purpose. Meaningful noise figures for the pumped nonlinear systems have been defined by comparing output parameters with source parameters. This definition of noise figures has the advantage that the figures thus defined are invariant to any further linear lossless transformations one may wish to use.