基于小波的声发射信号去噪研究

摘要

The wavelet transform is widely used in the denoising of non-stationary signal due to its strong time-frequency analysis and local analysis abilities. The signal is purified according to the energy percentage of each high-frequency coefficient after wavelet decomposition,and then performed with wavelet threshold denoising. The signal energy percentage and frequency spectrum analysis are used to evaluate the denoising effect. The experimental results show that the method to conduct the purification before threshold denoising can eliminate the noise in the acoustic emission signal effectively while ensuring that the signal is undistorted.%由于小波变换具有较强的时频分析和局部分析能力,常用于非平稳信号的去噪处理中.首先根据小波分解后各高频系数所占的能量百分比对信号进行提纯,再对提纯后的信号进行小波阈值去噪,并运用信号能量百分比和频谱分析对去噪效果进行评判.实验结果表明,这种先提纯后阈值去噪的处理方法能够在保证信号不失真的前提下,有效去除声发射信号中的噪声.