Design And Implement Of Bluetooth And Android Based Portable ECG Device

In the fast paced society, people are now living under increasingstress which will be the cause of cardiovascular disease. In diagnosingthose diseases, electrocardiogram, without doubt, is most direct andefficient way. Accurate extractions of ECG signal and careful analysis andreaches will effectively assist the doctors in analyzing and diagnosingthe illnesses.The traditional ECG monitoring devices are big and costly, not portableto be carried by the patients, and not suitable to achieve the long-termmonitoring. The expensive prices lay more burdens on the patients. Thus,it is necessary to design a small, cheap, portable device with low powerconsumption. The drawbacks of the traditional devices mainly originatedfrom the integration of functions. Taking all these factors intoconsideration and complying with the trend of rapid advancement of smartterminal devices, we try to divide the conventional ECG monitoring deviceinto two parts: signal acquisition unit and signal processing anddisplaying unit (the widely used smart phones and Tablet PCs will be perfectchoices). The units can communicate with the help of Bluetooth techniqueand then transmit the data. There are two advantages of processing anddisplaying signals on the smart terminal devices. Firstly, the costs andsizes of ECG monitoring devices can be reduced; the power consumptions canbe lowered. Secondly, the smart terminal devices have powerful signalprocessing abilities and scalabilities. Thus a new and better design comesout.To reduce the signal distortion to the minimum, the medical electrodesare selected to collect signals. The ADS1292produced by Texas Instrumentscompanies will be used to condition the ECG signal. The built-inprogrammable amplifier can offer flexible adjustment of the amplifier gain.The built-in right leg drive amplifier can effectively restrain the power line interference. And the built-in high-resolution24bits ADC canaccurately collect the signals and then convert the analog signals intodigital signals.51-Core MCU of STC15series produced by STC will be usedas host controller in ECG signal preprocessing unit. The host controllerwill conduct necessary initialization of ADS1292, simply process the datacollected by ADS1292, and then send the data to the smart terminal throughthe Bluetooth module. After receiving the ECG signal, the smart terminalfilter the baseline drift, power line interference, EMG interference andother inferences with digital filter. And then the R wave of ECG signalcan be detected and the heart rate can be obtained. At last the completeECG and heart rate will be displayed on the smart terminal. The ECG signalcan be saved in form of picture or data for further analysis and diagnose.At last the author made a detailed test of the ECG device, from theaspects of power consumption, transmission distance, bit error rate,compatibility test and accuracy etc. the testing result is satisfying. ThisECG device is easy to operate and to expand functions. With furtherimprovement and popularization, this device will be of great help toprevent and diagnose the Cardiovascular Disease.