基于小波变换的超声信号自适应消噪方法研究  

Research on Wavelet Transform Based Adaptive Noise Cancellation for Ultrasonic Testing

作　　者：罗雄彪[1] 万英[1] 

机构地区：[1]华南理工大学机械工程学院,广州510640

出　　处：《无损检测》2005年第12期617-620,642,共5页Nondestructive Testing

基　　金：广东省科技计划资助项目(2004A13003001)

摘　　要：超声检测中,特定的缺陷回波信号一般都有一定的相关性,因而可利用自适应噪声抵消来增强缺陷回波信号。针对最小均方(LMS)算法自适应噪声抵消的缺点,提出了基于小波变换的自适应噪声抵消方法,通过Matlab软件将该算法应用于超声缺陷信号的仿真处理。结果表明,该算法大大提高了缺陷回波信号的信噪比,且具有较高的缺陷定位精度和纵向分辨率。In ultrasonic testing, the flaw echo signals in A-scan are correlative. Thus, it is possible to enhance flaw echo signals by means of adaptive noise cancellation techniques. Adaptive noise cancellation based on wavelet transform was investigated aiming at covering the shortage of least mean square（LMS） algorithm. Its application to flaw echo signal simulation processing was realized hy Matlab. It was showed that the signal to noise ratio was greatly improved, and flaw location accuracy and longitudinal resolution were heightened.

关 键 词：超声检测 小波变换 多分辨分析 自适应滤波 噪声抵消 

分 类 号：TG115.28[金属学及工艺—物理冶金]