Design Of Portable ECG Monitoring System Based On STM32

At present,the problem of aging population is becoming more and more prominent in China,so that some social problems have been brought about,especially the number of people suffering from cardiovascular diseases has increased dramatically.At the same time,young people are also beginning to realize the heavy workload,the accelerated pace of life and the growth of age,this increase them suffer from risks of cardiovascular disease and various potential chronic heart disease.Based on this situation,a portable ECG monitoring system based on STM32 is designed in this paper,it is divided into four parts: ECG Analog Signal Acquisition Circuit、digital Processing Circuit for Analog ECG Signal、digital filtering、Upper Computer Software System.Thank to ECG signal is very susceptible to interference,a chip AD8232 with high integration and strong anti-interference ability is chosen as the main control chip of ECG acquisition front-end in this paper;the digital processing circuit of ECG signal is responsible for converting the analog ECG signal sent by the front end of ECG acquisition into digital signal,in this paper,STM32F103C8T6 is chosen as MCU of ECG monitoring system,at the same time,the way of wireless Bluetooth communication is used to realize data transmission with the host computer,Bluetooth module uses BLU4.0 with ultra-low power consumption;digital filtering is used to denoise the collected ECG signals,obtained Purer ECG signal by removing the interference signal contained in ECG signal,in this paper,the method of combining filter with wavelet transform is used to denoise the ECG digital signal;the upper computer is responsible for receiving the digital signal transmitted by the lower computer,and performing the functions of digital filtering,waveform display,heart rate calculation,data saving and system time display.The key part of this paper is the design of hardware circuit,owing to the characteristic of weak and susceptible to interference,taking the Crosstalk between modules and ripple coefficient of system power supply into fully consider whendesigning hardware circuit,at the same time,dividing analog signal and digital signal into regions in the PCB wiring process,after separating analog ground wire from digital ground wire,Connected by a bit of copper,this avoids electromagnetic interference caused by cross wiring.Through the design and debugging of the upper computer,It can display normal ECG signal well and achieve corresponding functions,achieved the expected goal,finally,it summaries the shortcomings in the research and also gives the prospects.