Polynomial time-frequency distributions and time-varying higher order spectra: application to non-stationary signal analysis

The paper deals with analysis and time-frequency representation of multicomponent signals characterised by non-linear frequency variation in time. A certain type of higher-order time-frequency distribution, referred to as polynomial Wigner-Ville distribution, has been designed to achieve delta function concentration in the time-frequency plane for this class of signals. In the presence of multiplicative noise, the signals are treated as being random and we introduce time-varying higher-order spectra (TV-HOS) as ensemble averaged polynomial Wigner-Ville distributions. TV-HOS are shown to be natural tools for analysis of non-stationary random signals, and we demonstrate this in the context of FM signals affected by multiplicative noise