一种改进的 MP-WVD 滚动轴承信号时频分析方法

Aiming at the problem of cross interference in the analysis of bearing vibration signals by Wigner-Ville distribution (WVD) method, a time-frequency analysis method based on improved matching pursuit (MP) algorithm and WVD is proposed. Firstly, based on the analysis of bearing vibration signal, the basis function of dictionary atoms in the MP algorithm is determined, and atomic parameters are determined by correlation filtering method to complete the dictionary construction. Then, fast Fourier transform (FFT) is used to calculate the cross-correlation spectrum between the signal and the atoms in the dictionary, and instead of the inner product operation in MP algorithm, the signal has the sparse representation, and the frequency parameters in the dictionary are updated according to the spectrum of the residual signal during the iteration process. Finally, the atoms in the sparse representation results are calculated by WVD, and the time-frequency representation of each atom is linear overlapping with the corresponding atomic coefficient as the weight to complete the time-frequency analysis of the signal. The experimental results show that it effectively improves the computing speed of MP algorithm, and compared with other three improved WVD algorithms, the time-frequency aggregation degree of the time-frequency analysis results of this paper method is higher, which can better overcome the cross interference term in the WVD method, and provide a new solution for the time-frequency analysis of the rolling bearing signal.