小波多分辨分析在超声回波信号去噪中的应用

在超声回波信号检测过程中，如何进行降噪处理一直是信号处理研究的焦点之一。该文应用具有优良的时频局部化能力的小波多分辨分析技术对回波信号作降噪处理，提取出材料缺陷处超声回波的主要特征信号。通过选取合适的分解和重构滤波器组，在有救提高信号的信噪比的同时也保持了良好的分辨率，从而实现缺陷识别和定位。在仿真实验中基于MATLAB环境对实际测量得到的超声回波信号进行噪声信号处理及特征提取，仿真结果证明了小波多分辨分析应用于超声回波信号降噪处理的有效性。

Application of Wavelet Multiresolution Analysis in the De-noising of Ultrasonic Echo Waveform

In the analysis of ultrasonic echo waveform,the de-noising technology has always been one of the focuses in signal processing.This paper utilizes the wavelet multiresolution transform,which can perfectly decompose a time series into both time and scale components,to analyze the ultrasonic echo waveform and extract the main feature of the echo waveform.By wavelet decomposing and reconstructing with appropriate filter parameters,the actual fatal feature is extracted with both high signal-to-noise ratio(SNR) and acceptable resolution ratio.In the MATLAB simulation environment,the noise removing and feature extraction of the measured signal are realized and experiment results show the effectiveness of the wavelet multiresolution analysis in the de-noising of ultrasonic echo waveform.