A Key Technology in Body Surface Potential Acquisition System——Electrocardiological Signal Digital Filter

This article introduces the wavelet basic theory and its important role in digital filtering area,and describes how to decompose and reconstruct the electrocardiological signal with Coif Wavelet and Mallet algorithm.It can solve the following three problems:1.selection of wavelet function;2.determination of frenqency feature of electrocardiological signal and noise;3.and determination of wavelet bandwidth in different measure.The results of experiments have proved that,by using Coiflet wavelet to filter electrocardiological signal,the baseline drift,powerline interference and electromyographical interference can be effectively removed.