基于鉴相器的手机瞬时心率监测软件设计

目前用手机摄像头监测心率的手机软件无法检测瞬时心率,因为手机上资源有限,而占用资源较少的主要检测方法差分阈值法需要根据一段时间的结果来设定阈值才能准确检测出心率,不适于瞬时心率的检测.针对以上问题提出了一种基于鉴相器的瞬时心率检测算法,通过手机摄像头检测出的脉搏波信号先与正弦参考信号相乘,再经过低通滤波器提取心率成分,根据相位的变化逐拍检测心率的变化.在Android智能手机上的实验结果表明,与ECG方法相比,计算精度能满足要求.与差分阈值法和滤波器组法相比,本文提出的方法能较快地检测出瞬时心率.

Software Design of Instantaneous Heart Rate Detection Based on Phase Demodulator for Smart Phones

Rarely software in the smart phone market can detect instantaneous heart rate quickly and precisely， because a threshold calculated based on a period of measurement is always necessary when using a derivative based algorithm. A phase demodulator based method was proposed to improve the performance of Android software. The pulse wave detected by cell phone camera was multiplied by a sine wave reference signal and then processed by a low pass filter to extract phase. The phase could be used to calculate the frequency beat to beat. Experimental results on an Android smart phone indicated that there was no obvious difference of instantaneous heart rate between the new method and the ECG method. Compared with derivative based and filter bank based algorithms， less phone resources was needed for the new algorithm and instantaneous heart rate could be obtained more quickly.