Analysis of FM signals affected by Gaussian AM using the reduced Wigner-Ville trispectrum

Abstract

A novel time-frequency analysis method for FM signals affected by multiplicative and additive noise is proposed. The method, referred to as the reduced Wigner-Ville trispectrum (RWVT), is a member of a class of time-varying polyspectra based on polynomial Wigner-Ville distributions (WVD) (B. Boashash and P. O'Shea, 1991). It is shown that the RWVT outperforms the Wigner-Ville distribution, and therefore any other method based on the Cohen's class of bilinear time frequency distributions (TFDs), for the class of signals considered. In addition, the authors present the statistical properties of an instantaneous frequency estimator based on the peak of the RWVT, and compare them with the properties of the estimator based on the peak of the WVD.