Unwrapping the Phase Response Functions for Nonlinear Systems

摘要

The phase unwrapping problem for nonlinear systems was studied. Two algorithmswere developed to unwrap the higher order generalized phase response functions. The higher order phase response functions contain important information about the behavior of nonlinear systems. Algorithms based on integrating the partial derivatives of the phase and using multiples of 2pi to amend the principle value were derived and implemented. The use of unwrapped phase allows the entire phase response to be calculated by superposing the phase of the various factors. The parametric estimation approach for the generalized frequency response functions provides a powerful tool for the analysis of nonlinear systems in the frequency domain.