独立分量分析在结构振动信号降噪中的应用

Application of Independent Component Analysis in Noise Reduction of Structural Vibration Signal

结构振动信号中混杂的噪声对信号的分析处理以及结构状态的诊断识别有很大影响。本文引入独立分量分析方法对结构动力信号进行降噪处理。通过增加实测噪声通道对多通道传感器信号进行扩展,利用有用信号与噪声成分之间相互独立,对信号进行ICA计算,将噪声与有用信号分离开来。对实验梁的实测振动信号进行分析处理表明,该方法降噪效果比较理想,而且降噪后的信号并没有改变结构动力特性。

The analysis of structure vibration signals is influenced by noise mixed in the signals. Independent component analysis （ICA） method is introduced to denoise the vibration signals in this paper. In order to satisfy the calculation condition of ICA, a noise passage is added to expand the multicenter sensor signals of structure. Because of the statistical independence of noise and signal, the noise can be separated from sensor signals by ICA. This method is proved effective by denoising the testing vibration signals in lab and the denoised signals do not change its dynamical characteristic.