LINEAR-QUADRATIC SYSTEM-IDENTIFICATION WITH COMPLETED FREQUENCY-DOMAIN REGION OF SUPPORT

In general, aliasing exists in the output of discrete-time nonlinear s ystems due to the higher order harmonics and intermodulation among inp uts. If the input is allowed to cover the full range from DC to half t he sample rate, the aliased components in the output must be taken int o account for accurate system identification. We have extended a known system identification method to account for these aliased terms by co mpleting the region of support for the quadratic transfer function. We also present a method for preventing a form of time domain aliasing. Together, these approaches can lead to significantly improved system c haracterization with less data as compared to current techniques.