基于毫米波雷达的心音检测  

Heart sound detection based on mm⁃wave radar

作　　者：王浩 张兴敢[1] WANG Hao;ZHANG Xinggan(School of Electronic Science and Engineering,Nanjing University,Nanjing 210023,China)

机构地区：[1]南京大学电子科学与工程学院,江苏南京210023

出　　处：《现代电子技术》2023年第23期12-18,共7页Modern Electronics Technique

摘　　要：心音信号的分割是心音分类和心杂音分析的基础,也是实现自动心音分析系统的关键。利用线性调频(LFM)毫米波雷达提出一种基于双特征的心音分割方法。首先通过LFM毫米波雷达获得被测试者的心音信号;然后提取出心音信号的一阶导数特征和频率包络特征,通过最大类间方差法计算特征阈值,将心音信号在时域上初步分割为第一或第二心音部分以及非心音部分;最后根据不同心音的生理特征,完成第一心音(S1)和第二心音(S2)的识别及心音信号的最终分割。实验通过毫米波雷达采集的不同受试者的心音数据对提出的算法进行了测试,提出的方法得到的平均F1分数为(90.49±2.30)%,而基于逻辑回归的隐半马尔可夫模型(LR-HSMM)算法得到的平均F1分数为(83.09±2.31)%。实验结果表明提出的方法具有更好的心音分割效果。The segmentation of heart sound signals is the basis for classification of heart sound and analysis of heart murmur,and it is also the key to achieve an automatic heart sound analysis system.In this paper,a heart sound segmentation method based on dual features is proposed by using linear frequency modulation(LFM)millimeter⁃wave(MMW)radar.The heart sound signals of the person⁃under⁃test is obtained by LFM MMW radar first,and then the first⁃order derivative feature and frequency envelope feature of the heart sound signals are extracted.The feature threshold value is calculated by the maximum between⁃class variance method,and the heart sound signals are preliminarily divided into the part of first heart sound,the part of second heart sound and the part of non⁃heart sound in the time domain.According to the physiological characteristics presented by different heart sounds,the first heart sound(S1)and the second heart sound(S2)are recognized and the final segmentation of the heart sound signals are completed.The proposed algorithm was tested by different subjects'heart sound data collected by MMW radar.The proposed method achieves an average F1 score of(90.49±2.30)%,while the logistic regression based hidden semi⁃Markov model algorithm,named LR⁃HSMM,achieves an average F1 score of(83.09±2.31)%.Experimental results indicate that the proposed method has better effect on heart sound segmentation.

关 键 词：毫米波雷达 心音检测 隐半马尔可夫模型 心音分割 心音提取 频率包络 逻辑回归 心音识别 

分 类 号：TN958-34[电子电信—信号与信息处理]