The Design Of Portable ECG Measurement Device

The cardiovascular disease is one of the main diseases which threatens human beings'health,while ECG is the important basis of clinical diagnosis of heart disease. With the functions of ECG testing, analysis and so on, the conventional ECG machine is usually expensive and large, and mainly used in large medical establishments such as hospitals. What's more, the probability of arrhythmia recorded is relatively lower when time is limited. Later, a portable ECG monitoring system is created, which can continuously record and store the data of heart activity. But lack of the function of automatic ECG analysis, its practical value is reduced thereby.Regarding of these disadvantages of the ECG testing system, we have designed a portable ECG monitor system, which can not only store and record ECG data, but also analyze the common arrhythmia. A performance excellent ECG acquisition system is designed according to the human ECG features, and the signal created by a high signal-to-noise ratio. By using high-capacity SD cards for storage media, a continued real-time monitoring can be realized. The system embedded with the FAT file system, and the ECG data can be stored as TXT files which makes the data file has a strong readability and portability. Based on 32-bit microprocessor LM3S1138 with ARM Cortex-M3 as a platform, the system, with powerful processing capabilities and low power consumption, can process large and real-time data. Its internal instruction and data bus are independent of each other and can be read from the memory at the same time. In addition to that, multiple operations can be also executed in parallel with a high quality. QRS complex detection algorithm is the core of the entire data analyzed and processed, with real-timing, accuracy and reliability as its basic requirements. Meanwhile,the accuracy can reach at 99% through the detecting of MIT-BIH ECG database. The designed monitor includes an LCD display which can display the ECG waveform and the real-time result of the data analysis. So it provides users a friendly interface by which the human-computer interaction can be realized with an easy operation system.After prototype is completed, the system performance parameters were tested. As the result suggested, the portable ECG measurement device can work continuously, reliably, stably in a long time. It owns a lot of features, such as large storage capacity, real-timing, safety, reliability, system versatility, portability, easy expansion, low power consumption, small size, and so on. Actual body testing indicates that, this ECG measurement device is easy to operate, stably with high accuracy. It also can monitor ECG in time and alarm when arrhythmia happens. This system achieves an ideal result, with those advantages are not only suitable for family medical care, but also throw a great significance on the cardiovascular disease monitoring.