摘要
结合多传感器时频分布(multisensor time-frequency distributions,MTFD)和盲源分离(blind source separation,BSS)的特点,提出一种针对机械复合故障信号的欠定盲源分离方法。首先利用Wigner-Ville分布将观测信号转化为MTFD矩阵;然后对该矩阵进行白化处理和噪声阈值处理,并对其自动项进行选择,对其特征向量进行集群处理,从而得到源信号TFD的估计;最后对源信号进行重建,得到源信号的估计。仿真及试验结果表明,本文所提出的方法在处理非平稳复合信号的欠定盲源分离方面具有很好的效果。
Taking advantages of multisensor time-frequency distribution(MTFD)and blind source separation(BSS),this paper presents an underdetermined blind source separation method for composite mechanical fault signals.Firstly,the observed signal is converted into an MTFD matrix by using Wigner-Ville distribution.Secondly,whitening and noise threshold processes are performed on the newly constructed matrix,and then the matrix's automatic items are selected and its eigenvectors are clustered in order to estimate the time-frequency distribution of source signal.Finally,the estimated source signal is obtained by reconstruction.Simulation and experimental results show that the proposed method is fairly effective on underdetermined blind source separation of non-stationary composite signals.
引文
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