径向高斯核函数时频分布及在故障诊断中的应用

摘要

A signal adaptive time-frequency distribution（TFD）-radial Gausian kernel TFD is studied． They introduce this TFD into fault diagnosis． This kind of TFD can tune its kernel ambiguity function shape by two-dimensional optimization procedure according to the characteristics of the analyzed signal． It offers improved TFD for a large class of signals over the fixed kernel TFD especially when the signal to noise ratio is low． The experiments are presented to show the RGK-TFD has superior character extracting ability than the traditional fixed kernel TFD that is often used in fault diagnosis．%对一种可调核函数的时频分布——径向高斯核函数时频分布(RGKD)进行了研究，并将径向高斯核函数时频分布引入机械故障诊断。这种时频分布根据被分析信号不同特性，采用优化方法自适应对模糊函数进行整形，尽可能保留集中在原点的信号模糊函数的自分量，抑制远离原点的交叉分量。与固定核函数的时频分布对比结果表明，径向高斯核函数时频分布极大地去除了交叉分量，提高了分辨率，并且对噪声不敏感，在分析实际低信噪比的信号时，仍能保持较高的分辨率，杂散分量很少，该方法具有对信号的广泛自适应性。试验证明径向高斯核函数时频分布在故障诊断中有较强的特征提取作用。