基于小波包的振动信号去噪应用与研究

Application and Research of De-noising of Vibration Signal Based on Wavelet Packet

小波包分析算法对上一层的低频部分和高频部分同时进行细分,具有更为精确的局部分析能力。基于小波包变换的优良时频分析特性,论述小波包分析的基本原理,研究小波包在振动检测信号消噪处理中的应用,给出应用小波包变换对基于MSP430F449单片机的信号采集电路所检测到的振动信号进行消噪处理的实例。结果表明小波包变换的方法可以降低系统噪声影响,通过变换分解出高频噪声部分,利用小波包收缩的阈值量化方法能够更好地去掉高频部分,从而达到有效去除信号中噪声的目的。

By means of the wavetet packet analysis, the low frequency part and high frequency part of the superstratum can be concurrently further broken down, and therefore, more exact analysis of localities can be conducted. According to the excellent time-frequency localization analysis properties of the wavelet packet, this paper introduced the basic principle of wavelet packet analysis, and researched the application of de-noising of vibration signal, and provided an example of de-noising of the signal detected based on MSP430F449 singlechip using wavelet packet. The result proves that the wavelet packet transform can eliminate the influence of the system noise, thus separating the high frequencies. After the decomposition, the wavelet shrinkage is performed with thresholding to eliminate the high frequency component, which can be applied in signal to denoise effectively.