Measurement of Electrocardiogram by using Fast Fourier transform

People usually ignore how their bodies react in the middle of busy and stress life. Although annual health check-ups can provide people health information, it is costing and time consuming. Moreover, people might miss the best treatment time since they cannot get the real-time health information. A study “10 leading causes of death in Taiwan” which was reported by Taiwanese government in 2007 shows that “heart disease” ranks a second, representing 9.3% of the death among Taiwanese resident. As a result, the observation of heart disease is an important topic in our daily life. In the hospital, doctors and nurses can use Electrocardiogram, ECG, to determine whether the patient’s rhythm has return abnormal result. This thesis will provide a real-time and easy to carry-on system for users to measure the Electrocardiogram at home and avoid the ignorance of heart disease. This self-monitoring system is composed by an analog processing module and a digital processing module. The analog processing module used OP-AMP to implement the amplifier circuit and filter circuits. In the digital processing module, a Texas Instrument microprocessor MSP430 is applied to convert analog signals to digital signals by a 12bits ADC and then using Fast-Fourier-Transform method, FFT, to get the Electrocardiogram in the frequency domain. Furthermore, the Electrocardiogram related information would be delivered to PC by using the UART interface. PC would analyze the data and provide users the frequency-spectrum. By using this system, users would be able to observe the abnormal rhythm and protect themselves from heart disease.