The Design And Realization Of A Ecg Collection And Transmission System Based On Bluetooth

Heart diseases often happen suddenly and are with high fatalness. In order to detect the illness in time, people need to conduct effective monitoring on the patients suffered from heart diseases. At present in domestic China, the most common way is to carry on real-time electrocardiogram monitoring on patients in hospital, which not only is too expensive for ordinary patients to afford, but also restricts their area of activities. we are in need of ECG monitor which is portable, economical and practical, So that we can discover and diagnose some disease early by self. In recent years, the rapid development of embedded systems technology provides a good technical condition for such studies. The paper designed an ECG acquisition and transmission systems. To process the ECG signal, The Method of combining circuit filter and digital filter is adopted. To transfer data to the receiving end (intelligent mobile phone etc), Bluetooth technology is used. The paper mainly does below studies:(1) The character of ECG waveform, the common interfering signals in mobile environment and the leads which are conventionally employed in clinical electrocardiography are analyzed. The character of Bluetooth technology is elaborated. Then the system design scheme was drawn up.(2) The system hardware is designed and implemented. Firstly, according to the ECG waveform characteristics analysis, The ECG signal acquisition circuit is designed, which mainly includes band-pass filter circuit, the right leg drive circuit and lead-fall circuit. Then the STM32F103microcontroller, a high-performance and low power Arm CPU is selected to design the central processing module for ECG signals processing and analysis. And the related interface circuit is completed, which includes microcontroller minimum system circuit, RS232interface circuit, A/D conversion chip interface circuit.At last the paper selects the Bluetooth module for transmission. (3) The relative ECG filtering algorithms are studied. The FIR filtering algorithm suitable for single chip which is to eliminate the interference of50Hz alternating current, and limiting filtering algorithm and weighted average recursive filtering algorithm which eliminate pulse noise are proposed.(4) The application-layer protocols based on the Bluetooth wireless communications is designed on data transmission, a detailed description of the communication process of the sender and receiver is given.(5) The system software is designed and implemented. It’s main function is to configure system clock, control A/D conversion chip by STM32F103SPI interface and complete ECG data collection periodically by Systick timer and send ECG data by UART.