Research And Implementation Of Vital Signs Monitoring With Radar Based On Adaptive Signal Analysis And Antenna Optimization

Vital sign monitoring plays a crucial role in the fields of medicine and health management.Impulse Radio Ultra-Wideband(IR-UWB)radar,with its high resolution,wide bandwidth,and strong penetration capabilities,has emerged as a novel non-contact solution for vital sign monitoring.However,current techniques for vital sign monitoring based on IR-UWB radar face challenges when dealing with overlapping radar signal components in multi-target scenarios.Moreover,the antenna,as a vital component of the IR-UWB radar system,directly impacts performance of radar,yet there is limited research on improving radar vital sign monitoring from an antenna optimization perspective.This thesis aims to investigate the adaptive identification of radar signal components in multi-target vital sign monitoring scenarios and optimize the antenna system to establish a foundation for achieving stable and robust monitoring.To overcome the challenges posed by overlapping and interference of radar signal components,this thesis proposes an adaptive analysis algorithm for radar signals in multi-target vital sign monitoring scenarios.The algorithm employs a constructed radar signal analysis network in combination with the Maximum Likelihood Kalman Filtering algorithm to adaptively extract multiple target trajectories,thus obtaining the corresponding human echo signals.Based on these echo signals,the AdaBoost classification algorithm is utilized to identify the body posture of each target,achieving high recognition accuracy.Furthermore,the thesis employs the variational mode decomposition algorithm based on the echo signals to estimate heart rate and respiratory rate,achieving an average accuracy of 84.2%in heart rate estimation and an average absolute error of 2.5 rpm in respiratory rate estimation.Experimental results demonstrate the effectiveness of this method.The thesis also focuses on antenna optimization to enhance the vital sign monitoring performance of the radar system.Three kinds of ultrawideband antennas,namely microstrip antennas,Vivaldi antennas,and horn antennas,are optimally designed to suit the characteristics of IRUWB radar.The performance parameters of these three optimized antennas are compared and analyzed,utilizing indicators such as standing wave ratio,radiation pattern and frequency-gain curve.Experimental data reveals that,overall,the performance of Vivaldi antennas and horn antennas surpasses that of microstrip antennas.Additionally,the thesis establishes a simulation system for IR-UWB radar,enabling a comprehensive analysis of vital sign monitoring performance based on each optimized antenna.