Diagnostic Techniques, Based On The Ecg Signal Of The Low-cost Processor

Electrocardiogram (ECG) is used in diagnosing arrhythmia in clinical. The purpose of this study is to develop a real-time QRS complex detection algorithm of dynamic ECG signals. Low-cost tele-monitoring system will be availabe by using this algorithm and save the time of rescuing patients.1) By a data compression algorithm based on extremum, the ECG data was compressed from high sampling rate to a low sampling rate. At the same time, the algorithm kept the most characteristics of QRS complex wave.2) By a strong filter, the noise signal is filtered. The cut-off frequency of low-pass filter was set around frequency of the QRS complex wave. And the data through moving windows intergration was used to calculate RR interval.3) The detection threshold of QRS complex was caculated by the average of data in last second. And the position of R point can be detected by the QRS complex position. Then the ST segment and QT interval would be caculated by the R point position.This algorithm can caculate the threshold in real time and use less RAM of microcontroller. It is very suitable for low-cost microcontroller like 51 series. A program diagram is designed in the paper, too. This program can save the RAM and time further.The algorithm is tested by using MIT - BIH arrhythmia database. The result of testing shows that the algorithm is effective.There are two appliance listed in this paper for showing the value of rescuing patient based on this algorithm and system.