Fast detection of system nonlinearity using nonstationary signals

This paper proposes a method for the detection and quantification of nonlinear distortions in the output of a dynamic system. The basic idea is to use a nonstationary excitation that makes the nonlinear distortions also nonstationary, thus making possible their differentiation from stationary plant noise. The nonstationarity of the excitation allows the evolution of the system nonlinearity to be assessed in one single shot, thus greatly accelerating the experiment.