自适应滤波心音增强

心音听诊是诊断心脏疾病的重要方法，近二十年在临床上得到了广泛应用．然而，心音传感器与皮肤的摩擦所产生的干扰，肺音在心音记录中的固有干扰等，而且有时这些干扰很强，给心音诊断带来了一定影响甚至误诊断．为防止呼吸干扰在记录心音时要求屏住呼吸或采用低通滤波方法，但滤波时滤去部分干扰音的同时，也丢失了心音的低频部分．本文采用的是自适应滤波，它可进行心音增强和抑制噪声．实验证实了本文方法的有效性

ENHANCEMENT OF HEART SOUNDS BY ADAPTIVE FILTERING

The cardiophony is the important method for the diognostic of heart diseases and gets its wide application in the last two decades. The friction on the body surface by the action of sensor, lung sounds in the recording of the heart sounds and the like are the main source of the interference and noise for PCG (phonocardiogram ). These interference and noise are strongenough as to produce the influence and error for diognostic. In order to prevent the interference of lung sounds it is required to hold the one's breath in recording of PCG or to adopt the lowpass filtering. In the second case the filtering can not only eliminate the interference, but also cause the loss of low frequency components of PCG. This peper presents the adaptive filtering method which can enhance the heart sounds and eliminate the noises. The experiments have verified the effectiveness of this method.