The Implications of Using Linear Frequency Response Function Estimators on Nonlinear Systems-a Functional Series Expansion Approach

摘要

In this paper we discuss the spectral approach to signal analysis and examine the effect of nonlinearity on traditional transfer-function estimators. To this end the Volterra and Fourier-Hermite functional expansions are reviewed and an expression for the cross-spectrum in terms of the latter is developed. The requirements for such a model to be effective are examined and the consequences for identification of nonlinear systems are discussed.