车辆加速度信号的EMD和IIR滤波联合降噪方法

Combined denoising method of vehicle acceleration signal based on EMD and IIR filtering

针对传统EMD分解中因高频IMF分量存在有用信号与噪声信号混叠的现象,导致降噪结果不理想的问题,提出了一种基于EMD分解和IIR低通数字滤波的联合降噪方法。在EMD分解的基础上,使用IIR低通数字滤波器对高频IMF分量进行滤波,将滤波信号与低频IMF分量进行重构得到降噪信号。最后使用某车辆加速度信号进行降噪试验,结果表明IIR低通数字滤波有效改善了高频IMF中信噪混叠的现象,验证了该降噪方法降噪效果优于EMD分解降噪和IIR低通数字滤波降噪。

To solve the problem that the noise reduction result is not ideal because of the aliasing of useful signal and noise signal in high frequency IMF component in traditional EMD decomposition,a joint noise reduction method based on EMD decomposition and IIR low-pass digital filter was proposed.On the basis of EMD decomposition,the IIR low-pass digital filter was used to filter the high-frequency IMF component,and the filtered signal was reconstructed with the low-frequency IMF component to get the denoising signal.Finally,a noise reduction testwas carried out with a vehicle acceleration signal,and the results show that IIR low-pass digital filter can effectively improve the problem of signal-to-noise aliasing in high-frequency IMF.It is verified that the effect of this noise reduction method is better than that of EMD decomposition and IIR low-pass digital filtering.