Design And Implementation Of ECG Real-time Filtering Algorithm Based On Single Chip Microcomputer

This subject achieves the function of filtering the 50Hz-frequency disturbing signal in ECG signal based on single chip microcomputer. This function module is the main function module of the ECG equipment, which can effectively provide accurate data and "pure" waveform for the feature extraction and analysis of ECG signal in the back-end module, which assists doctors to make accurate diagnosis.According to the actual development process of this function module, this thesis will be elaborated in several parts as follows: -First of all, this paper introduces the hardware platform of the system. According to the waveform characteristics of the standard ECG signal and the main interference which exists in the process of ECG signal acquisition, this thesis selects the appropriate front-end amplifier and microprocessor and then describes the structure principle of the amplifier and microprocessor respectively.Secondly, based on the study on digital filtering algorithm, this paper proposes a filtering algorithm which could filter the 50Hz-frequency interference signal under the condition of restricted RAM space in 8-bit single chip microcomputer. This algorithm has the characteristics, such as less operation, integer coefficients and so on, which is suitable for being achieved in single chip microcomputer. Through simulating the filtering algorithm in the Windows environment, the algorithm could achieve the anticipated filtering result.Finally, this paper designs the software structure of the filtering algorithm and describes the algorithm achievement process in single chip microcomputer. The data of real-time wave is made by ECG signal generator (including standard ECG signal and 50Hz sine interference signal), and the process of data acquisition and processing from the ECG signal is achieved through real-time A/D conversion, filtering and sending. Through comparing and analysis of the original waveform and the filtered waveform, the validity and availability of the algorithm is verified.