摘要： 讨论小波包阈值法去噪的机理，提出基于小波包变换的3σ规则和µ律阈值法在心音信号预处理中的方法，该方法保留小波包变换去噪的优势，能够有效地突出心音的特征部分，在心杂音信号去噪中有较好的效果。实验结果表明，该方法在去除干扰和心杂音上有着一定的优势，在心音信号检测中有重要的应用价值。

关键词: 小波包变换, 3σ规则, µ, 律阈值法, 心音, 去噪

Abstract: This paper discusses the principle of wavelet packet transform threshold de-noising used for restraining noise in nonstationary signal and puts forward a method of using 3σ-rule and µ-threshold method based on wavelet packet transform to pre-process the heart sounds. The method retains the advantages of normal wavelet packet transform in signal processing, and projects heart sounds’ features. Experimental results show that the method has a significant advantage on de-noising and heart murmurs processing, and it has a very good application foreground in heart sounds detection.

Key words: wavelet packet transform, 3σ-rule, µ, #NAME?, heart sound, de-noising

中图分类号: 

• R318.08