小波降噪在超声回波信号处理中的应用  

Application study of wavelet analysis on ultrasonic echo wave noise reduction

作　　者：周知进[1,2] 文泽军[1] 卜英勇[2] 

机构地区：[1]湖南科技大学机电工程学院,湘潭411201 [2]中南大学机电工程学院,长沙410083

出　　处：《仪器仪表学报》2009年第2期237-241,共5页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(50474052)资助项目

摘　　要：在深海采矿环境中超声波传输介质里存在着大量气泡、扰动沉积物、机械噪声等背景噪声与混响,导致有用信号与高噪声信号迭加在一起,严重影响了测距精度。采用小波分析方法将超声回波信号进行3层小波分解,适当设置门限阈值对小波系数进行处理,然后对信号进行重构,有效地抑制了信号中噪声对测量精度的影响。研究结果表明:小波方法有很好的降低回波信号中噪声的效果,其测距精度高于自适应滤波去噪后的测距精度。There are much background and mixture noise in the course of ultrasonic wave transmission under deep sea mining environment, such as air bubbles and disturbed sediment and mechanical noise. Because of these factors, the useful signals and the high noise signals are combined together, which seriously affects the distance measurement precision. Ultrasonic echo signals are decomposed into three layer wavelets, and a threshold is set to process the wavelet coefficients. Then the signals are reconstructed. Accordingly the influence of environment noise on distance measurement precision is effectively restrained. Research results indicate that wavelet transform method is very useful for noise reduction in signals. Its precision is higher than that of the adaptive filtering method.

关 键 词：小波变换方法 超声回波 降噪 

分 类 号：TN912.16[电子电信—通信与信息系统]