Identification of Wiener-Hammertein Systems Using the Best Linear Approximation

In this chapter, a nonlinear structure identification procedure is presented. The behaviour of the best linear approximation of some nonlinear block structures is given for the class of extended Gaussian excitation signals. The method is applied to a physical system, and the results are discussed. Next, a method is proposed to initialise the linear dynamic blocks of a Wiener-Hammerstein model. The idea is to build these blocks from the poles and zeros of the Best Linear Approximation of the system under test. The initial values are then further optimised via a nonlinear search routine. The proposed method is applied to measurements from an electronic Wiener-Hammerstein circuit.