Identification of non-linear unity feedback systems

An algorithm for the identification of non-linear systems which can be described by a model consisting of a linear system in cascade with a non-linear element followed by another linear system in a unity negative feedback loop is presented. Cross-correlation techniques are employed to identify the system in terms of the individual linear and non-linear subsystems. Parameterisation of both the linear and non-linear elements is discussed and the results of a simulation study are included to demonstrate the validity of the algorithm.