IDENTIFICATION OF WIENER-HAM MERSTEIN MODELS WITH CUBIC NONLINEARITY USING LIFRED

摘要

The identification of Wiener-Hammerstein models using linear interpolation in the frequency domain (LIFRED) is extended from models with quadratic nonlinearity to models with cubic nonlinearity. The modifications to the algorithm are discussed and a simulation example is presented. A further technique is proposed which enables the estimation of the gain response of the first linear subsystem from estimation lines in the output which are distorted due to contributions of several combinations of the input harmonics. This new technique is less susceptible than the first approach to the effects of noise and a possible reason for this is discussed.