基于N次峰值捕捉的超宽带雷达生命体征检测

Vital sign detection of ultra-wideband radar based on N peaks capture

针对心跳信号易被呼吸谐波和其他噪声干扰而难以提取的问题,提出基于N次峰值捕捉的生命体征检测算法。首先对雷达接收信号进行平均相消法处理滤除静止杂波;接着利用距离门选择算法提取出体表振动信号;然后对体表振动信号进行低通滤波和自相关处理去除随机噪声;最后,在提取呼吸频率的基础上抑制其高次谐波,进而在心跳频段捕捉M个峰值频率,并迭代N次统计心跳频段出现最多次数的峰值频率作为心跳频率。仿真结果表明,该算法相对于离散傅里叶变换(discrete Fourier transform,DFT)算法具有更高的测量精度和更好的抗干扰能力,可有效应用于生命体征检测领域。

Aiming at the problem that the heartbeat signal is easily interfered by respiratory harmonics and other noises and difficult to extract,a vital sign detection algorithm based on N peak capture is proposed.First,the radar signal received by the average cancellation method to filter out static clutter,and it uses the range gate selection algorithm to extract the body surface vibration signal;then it performs low-pass filtering and autocorrelation processing on the body surface vibration signal to remove random noise.On the basis of extracting the breathing frequency,its higher harmonics are suppressed,and M peak frequencies are captured in the heartbeat frequency band,then the peak frequency of the maximum number of occurrences of the heartbeat frequency band is calculated iteratively N times as the heartbeat frequency.Simulation results show that the algorithm has higher measurement accuracy and better anti-interference ability than the discrete Fourier transform(DFT)algorithm,and can be effectively used in the field of vital signs detection.