心冲击信号（ballistocardiogram，BCG）是由心脏搏动和大动脉血液循环引起的人体对外压力的变化，可用于无接触心脏活动检测。该文使用PVDF（polyvinylidene fluoride）压电薄膜，研制心冲击信号-心电信号（electrocardiogram，ECG）联合采集设备，并提出自适应模板匹配算法，基于心冲击信号计算心动周期，实现心率实时检测。采集24名健康成年人信号，对比ECG与BCG在心率检测方面的差异，同时评价算法的有效性。结果表明：BCG和ECG在计算心率方面无显著差异，自适应模板匹配算法查准率达到99.77%，查全率达到99.56%，准确性符合要求。
A ballistocardiogram (BCG) unobtrusively records the weight variation caused by the reaction force of blood ejection and blood flow in the aorta. A BCG system was developed to record BCG signals and detect the heart beats in the BCG signal. Data from 24 healthy subjects was collected to investigate the system with simultaneous electrocardiograms (ECG) as a reference. The results show no significant difference between the heartbeats detected by the ECG and BCG system (p=0.95) with the BCG system having a sensitivity of 99.56% and an accuracy of 99.77%.
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