A Method for Identifying Volterra Kernels of Nonlinear System Using Low-degree M-sequence

Abstract

Many classes of non-linear systems can be represented by Volterra kernels. In order to obtain the Volterra kernels, one of the authors has proposed a new method by use of M-sequences and correlation function.
In this paper, the authors propose a new method for polynomial approximation of non-linear system using the Volterra kernels measured by the M-sequence method. The non-linear system can be approximated as a combination of a linear system and its squared portion. The parameters, which represent the relative magnitude of the squared part, is calculated by use of the Volterra kernels.
The proposed method is applied to a non-linear chemical process. From the results of simulations, it is shown that the output signals of the non-linear system calculated by the proposed method agree well with the theoretical outputs.