Detailed research and design of remote ECG monitoring system
As a routine method for clinical examination of heart disease, electrocardiogram has the characteristics of non-invasive, simple operation, fast drawing, etc., and plays a decisive role in the diagnosis of various arrhythmia and conduction disorders. With the rapid development of related technologies such as computer networks and communications, ECG detection technology has gradually been applied to the field of telemedicine , making it possible for hospitals to provide telehealth services for heart patients. Up to now, China has developed an ECG transmission system that transmits ECG signals through fixed telephones. Due to large interference and high cost, it has not been used in clinical practice. To this end, this paper will study the design of a low-cost, low-power, portable wireless remote ECG monitoring system to provide convenient remote ECG monitoring services for heart patients. 1 System Overview The remote ECG monitoring system consists of an ECG detection terminal, a wireless communication network, and a hospital monitoring center. The block diagram is shown in Figure 1. The ECG detection terminal is used to collect and detect the patient's ECG signal, and then transmit it to the hospital monitoring center through the GPRS wireless network. After the host computer of the hospital monitoring center receives the ECG data through the network, the doctor can use the ECG in the host computer. The analysis software analyzes and classifies the patient's ECG signals. The ECG detection terminal can also directly transmit the ECG data to the computer through the RS 232 serial port. 2 system hardware design In order to design a small-sized, low-power, high-speed ECG detection terminal, the system uses the MSP430F449 MCU produced by TI as a microprocessor. The working voltage of the MCU is between 1.8 and 3.6 V. 1 MHz, 2.2 V active mode state, current is 280μA; 12-bit A/D converter with internal reference source, sample-and-hold, auto-scan feature; serial communication software with asynchronous UART and synchronous SPI modes selected. The device has a rich on-chip peripherals and a large-capacity on-chip working register and memory, saving a lot of space for the design of the circuit. The hardware of this system mainly includes ECG signal acquisition module, RS 232 communication module and GPRS transmission module. 2.1 ECG signal acquisition module The ECG signal is a very weak low-frequency signal with an amplitude of 0.5 to 4 mV and a frequency of 0.05 to 100 Hz. Other biosignals, 50 Hz power frequency interference and interference from surrounding electrical equipment are also mixed during the detection process. . Therefore, the ECG signal acquisition method consists of signal extraction, signal amplification, signal filtering and signal processing, as shown in Figure 2. Rice Transplanter,6 Rows Rice Transplanter,Walking Rice Transplanter,Efficient Manual Rice Transplanter Taizhou Yingtian Agricultural Machinery Manufacturing Co., Ltd. , https://www.sakuradaagc.com
