Research Of Human Vital Sign Monitoring Based On Millimeter Wave Radar

Human vital sign monitoring based on wireless signal is an emerging technology that has been proposed in recent years.The principle is that vital sign activities such as breathing will cause periodic micro-movement in the chest and abdomen,which will then have a regular impact on the reflected wireless signal.Therefore,the hidden vital sign information can be discovered through analyzing the wireless signal,so as to realize the sensing of human vital sign.In addition,compared with the traditional sensor active sensing technology,wireless sensing technology does not require the tester to wear professional hardware equipment,and can complete the sensing task in a "non-contact" manner,so it is more convenient and comfortable.And with the popularization and promotion of communication technology,more and more wireless devices,such as LTE,Wi Fi,millimeter wave radar,etc.,provide a broad development platform for wireless sensing technology,and promote it to smart home,health monitoring and other fields.At present,research on human vital sign monitoring methods based on millimeter-wave radar is in a stage of vigorous development,and it is necessary to explore the essential mechanism so as to provide strong theoretical support.At the same time,researchers also need to work hard to promote the practical application of this technology,so that it can benefit people's daily life as soon as possible.Therefore,this paper explores the theoretical research and practical application of human vital sign sensing,and proves the excellence of the proposed method and hardware system through experiments.In terms of theoretical research,this paper proposes three novel multiplexing mechanisms,namely angle division multiplexing sensing,range division multiplexing sensing,and source division multiplexing sensing.It tries to take advantage of the differences in Ao A,range,and source independence of multi-targets for separating the signal of each target from the mixed signal,so that the complex multi-target sensing is transformed into a relatively simple singletarget problem.In addition,this paper proposes the idea of jointly using three multiplexing mechanisms,so that more targets can be sensed in more complex actual scenes.Finally,this article also defines the concept of sensing capability,by adjusting the hardware parameters of system,to explore the theoretical limit conditions that can separate multiple targets.The multiplexing mechanism and related theories provide a systematic solution to the problem of multi-target sensing,and have important guiding significance for the experimental design of wireless sensing.In terms of practical application,this paper designs and implements a real-time human vital sign monitoring system based on 24 GHz millimeter wave radar.The millimeter wave radar chip,waveform generator,data acquisition card and other hardware are assembled into a portable hard plastic box.The stable and robust algorithm is designed to sensing the vital sign information of the target in the actual environment,and display it in real time on the simple UI interface.After many tests,the real-time system showed excellent sensing performance,demonstrating the huge potential and future direction of human vital sign sensing technology.This paper designs a large number of simulations and experiments to verify the reliability and superiority of the proposed multiplexing mechanisms and related theories.Through the analysis of the sensing capability,it points out the guiding role of the theoretical research on the design of wireless perception experiments.The experimental results show that the method and design system proposed in this paper can achieve significant sensing accuracy.