Design Of No-contactly Vital Sign Monitoring System Base On Doppler Radar

With the continuous growth of China's health electronics market,the demand for health electronic products are strongly increasing.The non-contactly Vital sign detection technology based on Doppler bio-radar are favored by health electronics because of its own non-contact,penetration and other advantages,it has great potential for daily health monitoring,Special population monitoring,medical diagnosis,intrusion detection,disaster relief and other fields.there are some problems in the study of non-contactly vital signs detection based on Doppler radar,for example:real-time radar signal processing is required in long-term monitoring;cardiopulmonary information should be reconstructed linearly;time-domain cardiopulmonary information is difficult to distinguish from strong clutters.In view of the application of health care,medical and other applications,according to the actual application demands and combined with the above issues to start the study:(1)According to the principle of Doppler radar and the application of vital signs detection,the working mode,operating frequency,antenna and transceiver structure of Doppler radar are determined by studying the basic theory of Doppler radar.(2)Research on real-time detection of cardiopulmonary activities.In view of the daily physiological signs of monitoring demands,emphasizing the real-time of software,low power consumption and low cost of hardware,focusing on the authenticity of signs of information,cardiopulmonary parameters estimation and extraction accuracy.Short-time Fourier transform(STFT)and spectral interpolation were used to extract real-time heart rate and respiration rate.(3)In the system developmentSystem,taking Fully considered of the actual monitoring applications and the current social medical service model,exploring the actual requirements of real-time,precision,portability and integration,designed and implemented of the Doppler-based biological radar intelligent detection,combined with mobile and desktop monitoring platform to build a Doppler radar vital signs monitoring system.The actual experimental results show that the real-time feature extraction algorithm has more than 96%accuracy in heart rate detection and even nearly 100%accuracy in respiration rate detection.