基于形态学的心电信号基线漂移矫正方法

Removal method of baseline drift from ECG signals based on morphology filter

基线漂移噪声是心电信号(ECG)中噪声的主要组成成分,矫正基线漂移是心电信号预处理的重要一步。目前,矫正ECG信号中基线漂移的方法包括小波变换、曲线拟合法以及FIR和IIR滤波的方法,但因计算量较大、实时性受信号长度影响和截止频率固定等因素,使得滤波带来不便。提出数学形态滤波器来矫正基线漂移,并根据心电信号的几何特征设计参数。经验证:该方法能有效矫正基线漂移,较好地保留信号特征。

Baseline drift is the main noise of ECG signals which its removal is an important step in the ECG signal preprocessing. At present, methods to correct the baseline drift in the ECG signal include wavelet transform, curve fitting as well as FIR and IIR filtering method. But factors such as the large amount of calculation, signal length effect real-time and the cut-off frequency of the filter give the work inconvenience. This paper presents the mathematical morphological filter to correct the baseline drift, according to the geometric parameters of ECG signal. The experiments prove that the method effectively corrects the baseline drift, preserving signal better.