基于LabVIEW的超声信号小波阈值去噪方法

图形化编程软件LabVIEW具有强大的信号采集功能,但对于需要进行大量数据运算处理的复杂应用就显得力不从心。数学工具软件MATLAB强大的计算功能及较高的编程效率可以弥补LabVIEW开发的不足。文中结合两者软件的优点,采用混合编程的方法进行实际工程的去噪处理,同时针对超声缺陷回波信号信噪比低、易于被噪声淹没的特点,选取小波阈值去噪的方法,通过调用LabVIEW里的MATLAB Script节点对信号进行仿真实验,仿真结果表明采用stein的无偏风险阈值去噪的方法消噪效果最为明显,得到较高的信噪比。

Wavelet Threshold De-Noising Method of Ultrasonic Signal Based on LabVIEW

Graphical programming software LabVIEW has a very strong signal acquisition function,but to process large amounts of data computing for complex applications,it becomes powerless.Mathematical tool software MATLAB with powerful computing and higher programming efficiency can make up for the lack of LabVIEW development.Absorbing the advantages of the two software,use the hybrid programming approach to practical engineering de-noising.At the same time,signal to noise ratio for ultrasonic flaw echo signal is low,and the signal is easy to be drowned by the noise.Owe to the characteristics,select the method of wavelet threshold,by calling the MATLAB Script node for signal simulation.Simulation result shows that the stein＇s unbiased risk threshold method can get better de-noising effect,and it gets a higher signal to noise ratio.