Research And Implementation Of The Wireless ECG Monitoring System Design

With the acceleration of the process of global aging and people’s livingstandards improving, cardiovascular and other chronic diseases become the numberone killer endangering the health of people. Real-time monitoring of ECG and otherphysiological parameters can partly reduce and prevent the harm of these chronicdiseases. Due to the development of modern e-health technology, efficient portableor wearable ECG monitoring devices go into the day-to-day diagnosis of thecommunity hospital or home. The Body Area Network (BAN) describes thatwearable or implantable health sensors sent their datum to the remote terminalthrough wireless communication. It helps people to monitor their health parametersuninterruptedly and without much influence of their daily lives. It also brings newlight to low-cost, low-power, portable monitoring devices. The medical telemetrysystems using wireless communication by means of electromagnetic waves of RFcan be applied for this purpose. In actual use, such system is surrounded by manyelectromagnetic noise sources which give serious effect to wireless datatransmission by a RF wave. Since RF link power consumption has brought greatchallenges to the low-power design, it is difficult to obtain in the wireless type ECGmonitoring system.An effective portable wireless system for continuous monitoring of ECG isproposed. It is powered by ordinary lithium battery and uses intra-bodycommunition (IBC) for wireless transmission of ECG datum. The ECG monitoringsystem integrates functions for ECG acquisition, wireless transmission, storage anddisplay. Compared with other traditional systems, it has advantages of safe andreliable transmission and energy-efficient power designs. On the basis of IBC theoryand human channel analysis, we design a human body based, half-duplex andcapacitive coupling IBC transceiver which is composed of FPGA, logarithmicamplitier, analog comparator and band pass filter. The IBC transceiver works in the40MHz band and uses thte On-Off Keying (OOK) modulation and8B/10B encodingthat is based on digital circuit design. ARM microprocessor LPC2148controls theIBC transceiver through a modified SPI serial communication protocol. We madesome interface circuit designs and ARM-based embedded programming. They helpthe data recorder to store the inbound ECG data in SD card based on FatFs filesystem, to commnicate with PC through the USB device and to come true someother auxiliary storage and display functions. The inbound ECG data can bedynamically displayed in a PC software which is designed in Visual C++. The ECGdata are obtained from a ECG device which is developed by the Shenzhen Institute of Advanced Technology.Based on the ECG sensor and intra-body communication, a new wireless ECGmonitoring system is developed. It provides throretical and practical basises forreliable, secure, low-cost, low-power, portable wireless ECG monitoring systemdesign. The system proposed provides the funtions of ECG wireless transmission,real-time storage and display, which reduces the complexity of traditional ECGmonitoring systems, promotes the progress of the ECG monitoring technology, andlays a good foundation for the BAN.