Spectral Analysis for Nonlinear Spectral Analysis Part 1: Parametric Nonlinear Spectral Analysis

A new theory of spectral analysis for nonlinear systems is introduced. The method consists of estimating the parameters in a NARMAX model description of the system and then computing the generalised frequency response directly from the estimated model. The paper is divided into into three parts. Part 1 introduces a methodology for estimating the models and computing the frequency response functions. Part 2 concentrates on the interpretation of the nonlinear frequency response functions and Part 3 describes a series of case study examples and illustrates in detail how to apply the algorithms to real systems.