On sampling and prefiltering in nonlinear system identification

A number of design variables is available in system identification to increase model accuracy in specified frequency bands: among others, one can resort to prefiltering or choose the sampling interval in a suitable way. In this paper a framework for the extension of the analysis of the role of sampling and prefiltering from linear to nonlinear system identification is proposed. In particular, a frequency domain interpretation is provided, based on the use of Volterra series representations for the true system and the considered model structure. Simulation results illustrate the conclusions of the analysis.