A New Method to Suppress Cross-Terms of WVD via Thresholding Superimposition of Multiple Spectrograms
基于多谱图叠加阈值的抑制WVD交叉项的新方法

In this paper, a new method is proposed to suppress the cross-terms of Wigner-Ville Distribution (WVD), which is based on thresholding the superimposition of multiple spectrograms. First, the spectrograms with different time-frequency resolutions are superimposed and then the superimposition is thresholded to localize the auto-term support region of the WVD. Secondly, the WVD is multiplied by the indication function of the region. In this way, a new Time-Frequency Distribution (TFD) is obtained. Unlike the traditional kernel function methods to suppress cross terms, our method not only reduces the interfering cross-terms but also preserves the superb time-frequency concentration of the WVD. The experimental results show that the method is very effective for both the multicomponent signals consisted of the LFM’s and nonlinear frequency modulation chirp signals.