Design of a Non-Contact Vital Sign Detection Device
In order to solve the problem of not being able to direct use traditional wearable monitoring instruments to monitor human vital signs in real time in clinical medicine,emergency or home care applications,a non-contact vital sign detection device based on Doppler radar is designed,which extracts human respiratory and heartbeat signals from the signals detected by Doppler radar in real time through the STM32F429IGT6 controller.The hardware mainly consists of microcontroller,Doppler radar sensor signal amplification circuit,filte-ring circuit,level boosting circuit,etc.The system achieves the separation and extraction of respiration and heartbeat signals through IIR bandpass filtering,and uses FFT to perform real-time spectrum analysis on the separated respiration and heartbeat signals to calculate and display the respiration and heartbeat counts.The test results show that the device can effectively detect the human breathing and heartbeat counts in real time,and realize the non-contact human vital sign detection within 2 meters,with the maximum mean error of 9.14%for the heartbeat count and 4.7%for the breathing count.