超声检测信号中的小波包分析  

WAVELET PACKET ANALYSIS TO SIGNAL IN ULTRASONIC TESTING

作　　者：罗雄彪[1] 陈铁群[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：《机械工程学报》2006年第4期142-146,共5页Journal of Mechanical Engineering

基　　金：广东省科技计划资助项目(2004A11303001)

摘　　要：超声检测中缺陷回波信号的质量是实现缺陷定位定量定性分析与评价的基础,去噪是超声检测信号处理中很重要的环节。小波包分析方法可以有效地抑制噪声干扰,提离有用信号。在Windows环境下,采用MATLAB 6．5 编程实现了缺陷回波信号的小波包去噪处理。研究结果表明:利用小波包阈值去噪,大大提高了缺陷回波信号的信噪比,改善了信号特征信息的质量,并且具有较高的缺陷定位精度和纵向分辨率。In the process of ultrasonic testing, the quality of flaw echo signals in A-scan lay a better determinant foundation for locational, quantitative and qualitative evaluation. The signal and noise are effectively distinguished by means of wavelet packet analysis techniques. Under Windows circumstance and by use of MATLAB 6.5 program language, it is realized that application of wavelet packet analysis in ultrasonic signal is aiming at de-noising. From the results obtained in experiment, it can be seen that the signal to noise ratio and the effect of signal characteristics are greatly improved, and flaw location accuracy and longitudinal resolution are advanced too.

关 键 词：超声检测 去噪 小波包分析 信噪比 

分 类 号：TG115.28[金属学及工艺—物理冶金]