一种双正交心音小波的构造方法

为了提高小波分析在心音信号处理中的性能, 在分析小波构造理论的基础上, 构造了一种专门用于心音信号处理的小波基. 首先提出一种构造滤波器长度为偶数的紧支撑双正交小波的一般方法; 然后根据心音信号的特点, 讨论心音小波的构造原则和一种基于心音 小波族的心音信号合成模型, 并且在此基础上构造出心音小 波. 为了突出使用心音小波处理心音信号的先进性和实用性, 对心音小波进行了比较全面的理论和数值仿真分析. 实验结果表明, 相比常用的db, bior系列小波, 运用心音小波对心音信号进行处理, 能够获得更好的去噪效果、 更精确的心音分类信息以及更小的重构误差率, 为心音特征提取和身份识别的深入研究提供了一种新方法, 在表征心音个体特征的细节方面具有积极的意义. 本文根据应用对象设计专用小波的方法也为工程应用中小波基的选择提供了一种新途径. 关键词： 双正交小波 心音小波 构造方法 心音合成模型

A construction method of biorthogonal heart sound wavelet*

In order to improve the performance of the wavelet analysis in the process of the heart sound signals, in this paper, we construct a wavelet basis which is exclusively used for processing the heart sound signals on the basis of wavelet theory construction. Firstly, we propose a general method of constructing a compactly supported biorthogonal wavelet which has even length filter banks, Secondly, according to the characteristics of heart sound signals, we discuss the structure principle of heart sound wavelet and a synthesis model of heart sound signals based on the heart sound wavelets. Finally, we construct the heart sound wavelet on the basis. In order to highlight the advanced nature and practical application of heart sound wavelet in processing heart sound signals, the theory and numerical simulation of heart sound wavelet are analyzed more comprehensively. Experimental results show that compared with commonly using the db and bior series wavelets, using the heart sound wavelet to process the heart sound signals can obtain good denoising effect, accurate classified information about heart sound and low reconstruction error rate. So the heart sound wavelet provides a new method of deep studying of heart sound feature extraction and identification and has a positive significance in describing the details of the individual characteristics of the heart sounds. The paper designs a method of the special wavelet which is based on the application object, which provides a new approach to the selection of wavelet basis in engineering applications.
Keywords： biorthogonal wavelet heart sound wavelet constructor method a synthesis model of heart sound signals