Modelling of nonlinear elements with memory

Two simple models are proposed for Saleh's subclass of nonlinear elements, which can be represented by frequency-dependent AM/AM and AM/PM characteristics; solid-state power amplifiers and cavity-coupled TWTAs are the application. It is noted that the simplicity of these models makes them appealing for analysis and simulation considerations. Using these models, the analysis techniques which have been developed to investigate signal behavior through effectively memoryless nonlinear elements (e.g., helix-type TWTAs) can be directly applied. Straightforward identification schemes connected with these models are presented.