Suppression of cross-terms in Wigner-Ville Distribution based on short-term Fourier transform

摘要

The time-frequency analysis method studies the spectrum of signal at a certain time, and can analyze the signal locally. It is suitable for the analysis of non-stationary signal. For time-frequency analysis of cosine signal contained in multi-frequency component, with the property of short-term Fourier transform (STFT) not generating cross-term, STFT and WVD (Wigner-Ville Distribution) are combined. In this way, generation of cross-term is suppressed while maintaining high time-frequency resolution. For partial discharge signal is simulated and analyzed using MATLAB. The simulation results show that: through the means to restrain the generation of cross terms, get the correct frequency information of multi frequency signal, also reflected in the frequency diagram frequency aggregation of good, is conducive to the detection and processing of multi frequency signal or signal superimposed composite signal.