心电信号预处理数字滤波器的设计与分析

Design and Analysis of Digital Filter for ECG Signal Preprocessing

针对原始心电信号(Electrocardiogram,ECG)中工频干扰和基线漂移两种主要噪声,设计了基于经典法的切比雪夫I型、整系数IIR以及基于布莱克曼窗的FIR陷波器抑止工频干扰,并且还设计了巴特沃斯和基于z平面的简单极点法的高通滤波器对范围在0.15~1.5 Hz的基线漂移低频干扰信号的滤除.通过对时域和频域观察的滤波结果显示,这些滤波器均能有效滤除干扰.

In the original ECG signal,it mixes two kinds of noise with power-line interference and baselinedrift. In this paper,the Chebyshev I filter and the coefficient of IIR filter based on classical method,andthe FIR filter based on Blackman window,which are designed to reduce power-line interference. Besides,the Butterworth and high-pass filter based on z plane and simple pole method are designed to filter the lowfrequency of baseline drift in the range 0.15-1.5 Hz. The filtering results in the time domain and frequencydomain show that these filters can effectively filter the interference.