Quadratic System Identification By Hereditary Approach

Quadratic systems are the first kind of nonlinear systems in which we are interested in order to study polynomial nonlinearities. They can be approximated by bilinear models with nilpotent structure that approximate certain nonlinearities and generate finite degree Volterra series. The hereditary identification algorithm limited until now to linear systems is extended here for identification of nonlinear systems by implementing a canonical structure to the approximant of degree two (quadratic). A NARX (nonlinear autoregressive exogenous input) multidimensional expression is employed in order to perform identification by hereditary computation