Application Of Wavelet Transform In Remote Electrocardiogram Monitoring System

With the development of the society economy and life, cardiac diseases have been one of the major diseases that harm human's health. As ECG (Electrocardiograph) reflects the state of the cardiac system, there is important meaning to research the ECG signals. The development of remote electrocardiogram monitoring system has solved the limit of time and space. Also the transmitting signal should be processed correspondingly, so that doctors can get the real condition in time.Wavelet Transform Theory is a Time-Dimension method of signal analysis. It has the characteristics of multi-resolution and can be used to describe the local characteristic of signal in both time field and frequency field. Because of the extra performance in signal processing, in the area of Biomedical Engineering, it has been widely adopted in Signal Detecting, Feature Extraction, Image Processing, Signal Compression and so on.In this paper, the history of remote electrocardiogram monitoring and its current research state in home and abroad are introduced at first, and then the principle and the characteristics of ECG are explained. Based on theory of wavelet transform, the compression method, denoising method and QRS detecting method of electrocardiogram are discussed profoundly. Self-adaptive coding method based on wavelet transform is used in this paper to compress ECG signal, which has fine effect. In denoising procession, noise is removed according to their category, the simulating results are also given.A method using wavelet approximation is used to remove the baseline wanders in electrocardiogram. In order to remove muscle artifact and power frequency interface, a method combining nonlinear threshold with modular maximum denosing method by wavelet transformation is used. It effectivelyremoves the noise and also maintains the higher frequency of QRS at the same time. When detecting QRS wave, quadratic differential wavelet is used to detect R wave, and then locate Q wave and R wave.Finally, Both hardware and software of the remote electrocardiogram monitoring system are designed, so that wavelet analysis used in remote electrocardiogram monitoring system is realized .