The Research And Design Of Intelligent Detection & Analysis For Mobile Cardiac Telemonitoring System

Telemedicine is one kind of service system that uses communication technology to provide cure, health care and consultation for remote patient. Telemonitoring and Home Health Care (HHC) is important but relatively weak research field of the telemedicine. Because cardiopathy and hypertension have characteristics of abruptness and dangerousness, generally, telemonitoring of ECG is thought as important application of HHC. The system of telemonitoring developed by us is a new telemonitoring system out of hospital that can automatically alarm, real time monitor, diagnose and supervise first aid. The monitor center can monitor patient's ECG transmitted by mobile communication. The system can not only be thought as a part of ICU/CCU but also help doctor to diagnose unknown heart-throb, breast ache and swoon, or detect miocardial infarction, ventricle arrhythmia and hypertension and direct treatment The research is divided into three parts: 1) Terminal that can intelligently alarm and real time transfer data Intelligent mobile terminal has a MSP430 that can get ECG data. We designed active electrode that can promote the quality of signal. The MSP430 has a small dimension and integrates a lot of outer circuit, so the main unit takes small space. Moving amplifier circuit to front and using micro IC can make main unit smaller. After amplified and pretreated, the signal is transmitted to main part of terminal by serial port. The MCU of main part uses SAMSUNG S3C44B0X that is ARM7TDMI structure, and runs ucLinux operation system. By using TCP/IP stack and PPPOE protocol embeded, firmware control mobile communication module to transmit the abnormal ECG data to monitor center. The type of communication module can be GPRS or CDMA. 2) Mobile communication and data server The mobile communication can be divided into two parts: wireless data transmission and internet. According to transmission type, it can be GPRS or CDMA network. The ECG data is transmitted to base station, and then sent from the base station to data server in internet though IP. The module sending ECG data is GPRS modem or CDMA modem. They use AT instruction to control modem. Generally, we don't directly use these instructiones, and these instructiones are used by ucLinux. After creating data link, ucLinux uses TCP/IP stack to send ECG data. Data is transmitted to data server though internet. So data need a gateway server to manage and distribute. 3) Monitor center Real time ECG data is distributed to work station in monitor center. Doctor can see alarm and ECG data through the work station, and make cure response if any. A precise real-time QRS detection algorithm based on local minima of second derivatives and cross-zero points of first derivatives of ambulatory ECG signals to meet the need of mobile ECG telemonitoring system is developed in this dissertation. The flash chip can storage ECG data for more than one day. So the system can also replace Holter. Doctor can diagnose disease according to ECG data storage in flash card. The technology in this dissertation has realized in products and proved effective by clinical test.