A New Method for Interference Reduction in the Smoothed Pseudo Wigner-Ville Distribution

This article presents a new method facilitating interference reduction in the Wigner-Ville distribution, which is used for nonstationary signal analysis, for example in machine condition monitoring. The algorithm is based on multiple Smoothed Pseudo Wigner-Ville distributions: differently smoothed time-frequency planes are compared and, for every point, a cross-term free value is calculated on the basis of optimal smooth estimation. The proposed approach is compared with the Gabor-Wigner transform, the Zhao-Atlas-Marks distribution, and the Choi-Williams distribution. Five time-frequency Gaussian atoms and a bat echolocation chirp are used as the testing signals. The Rényi entropy, the ratio of norms, the Stanković measure, and the mean squared error are used as quantitative measures to demonstrate the promising results of the proposed method.