一种应用于心磁噪声抑制的选择性平均方法研究

Study of a selective averaging method for magnetocardiography-based noise suppression

在心磁信号探测中,抑制环境噪声是提取心磁信号的关键.为了提高心磁信号的信噪比,信号平均得到了广泛地使用.然而,由于局部干扰噪声的存在,对整段数据进行平均的传统方法不可避免地会带来心磁信号的失真.本文通过采取模版匹配的方式,提出了一种选择性平均方法.结果显示,本方法能有效剔除带有低频波动、脉冲毛刺等干扰的数据段,获取高质量的平均心磁信号.

Noise suppression is a key technique in retrieving weak magnetic signal from human heart. In order to improve the signal-to-noise ratio （SNR） of magnetocardiography （MCG） signals, signal average method is widely used. However, due to the existence of local environmental interference, averaging the whole section data would unavoidable bring distortion to the average signal. In this paper, the authors proposed a kind of selective average method by using the template matching. The results showed that this method can effectively eliminate the data section with interference such as low frequency fluctuation, pulse burr etc. Thus averaging MCG signal with high SNR and fidelity will be obtained.