抑制Wigner-Ville分布交叉项方法的比较

The Comparison of Methods that Inhibit Wigner-Ville Distribution's Cross-term

由于Wigner-Ville分布对于多分量信号存在交叉项的干扰,影响了特征提取的准确性。利用Choi-Williams分布,可以有效地抑制上述存在的交叉项问题,但其时频聚集性有所下降。因此,提出了基于EMD的Wigner-Ville分布进行特征提取,并在数字仿真振动信号上加以验证。分析结果表明,该方法解决了交叉项和时频聚集性下降问题。

Wigner-Ville distribution can reveal the nature composition of the non-stationary signal from the combination approach of time-domain and frequency-domain, while the existence of cross-term interference in multi-component signal affects the accuracy of feature extraction. Using Choi-Williams distribution to extract feature from signal can effectively inhibit Wigner-Ville distribution＇s cross-terms, but meanwhile, decreast the aggregation of time-frequency. In face of these problems, this article has achieved a better result by putting forward the EMD-based Wigner-Ville distribution to extract feature from the digital and test it using simulated vibration signal.