Design of Portable On-line ECG Monitor

Electrocardiogram (ECG) monitors can not only measure ECG signals in real-time but also predict the likelihood of future cardiac conditions. However, current ECG monitors have limitations such as high costs, large size, cumbersome operation, and limited application scenarios, which restrict their use in everyday life. To address these issues, this paper studies ECG signals and noise, and designs a portable on-line ECG monitor based on the STM32 microcontroller. The ECG data acquisition sensor used is the AD8232, and a median filter is applied to process the collected ECG signals. The median filter model which is most suitable for ECG filtering is designed, and the analysis of variance is designed to evaluate the filtering effect. The monitor displays ECG waveforms on its built-in LCD screen and features a SYN6288 voice broadcasting chip for audio output. The monitor also employs a Mini SD card for data storage and is equipped with an HC-05 Bluetooth module for data transmission. The designed monitor has a compact area of only $70 \mathbf{~ c m}^{2}$, offering low cost, portability, high-precision measurement, and real-time data transmission, making it suitable for a variety of applications.