【摘要】 详细介绍了驻极体传声器在心音信号采集中的方法,包括心音信号提取的方案、原理、规则及传声器的阻抗变换问题。同时,为了不使环境电磁噪声埋没有临床价值的心音,对传声器进行了屏蔽保护。临床实验表明,利用驻极体传声器基本上能采集到正常的第一、第二心音,但对有病理信息的第三、第四心音却不易正确采集到,这与患者性别和胖、瘦等因素均有关系。更多还原

【Abstract】 Heart sound is a faint signal which is difficult to be acquired.This paper presents the methods for the heart sound acquisition used electret microphone,including the heart sound extraction project,principle,rules and the impedance conversion of microphone.In order to acquire the useful heart sound,the microphone is shielded by a special device.The clinical experiments have indicated that the first and second heart sound can be almost acquired by the microphone,but it is difficult for the third and fourth,which are affected by sex and bodily form.更多还原