Cross-term suppression in the Wigner-Ville distribution using variational mode decomposition

Time-frequency distributions (TFDs) are strong mechanisms for close investigation of non-stationary signals to find out its unique properties. A well known TFD method known as Wigner-Ville distribution shows false-components along-with auto-components. This article presented a novel approach to overcome the issue of cross-terms in Wigner-Ville distribution (WVD) for linear signals. In this method, variational mode decomposition (VMD) is utilized to obtain the narrow-band components correspond to a multi-component non-stationary signals. After decomposition of the signal, WVD is applied on each obtained component for getting the TFD of each and every mode. Final cross-terms free WVD is obtained by adding the WVDs of all the resulting modes. The presented methodology has been compared to the smoothed pseudo-WVD (SPWVD) method. The experimental analysis justify that the suggested technique provides the cross-terms free TFD of multi-component non-stationary signals.