基于回归支持向量机的胎儿心电提取

Extraction of Fetal Electrocardiogram Using Support Vector Regression Machine

针对胎儿心电难以提取的问题,提出一种从母体腹壁混合信号中提取胎儿心电的方法。首先利用回归支持向量机(Support vector regression machine,SVRM)拟合母体心电传导至腹壁所经历的非线性变换,然后将母体心电经由所拟合的非线性变换得到腹壁混合信号中的母体心电干扰的最优估计,再从腹壁混合信号中减去母体心电干扰的最优估计得到含噪声的胎儿心电,最后通过小波包去噪技术抑制胎儿心电中的基线漂移和噪声,得到清晰的胎儿心电。在胎儿心电和母体心电QRS波完全重叠的情况下,通过该方法能够提取出清晰的胎儿心电。实验结果验证了该方法的有效性。

A novel method based on support vector regression machine （SVRM） is proposed to extract the fetal electrocardiogram （FECG） from the abdominal composite signal of the pregnant woman. The maternal electro cardiogram （MECG） interference in the abdominal composite signal is a nonlinearly transformed version of the MECG and this nonlinearly relation is identified by the SVRM. An optimal estimation of the MECG interference in the abdominal composite signal is obtained by the MECG undergoing the nonlinear transformation. The fetal electrocardiogram（FECG） is extracted by removing the optimal estimation of the MECG interference from the abdominal composite signal. The baseline shift and the noise in the extracted FECG are suppressed by the wavelet packet denoising technique. Experimental results show that the clear FECG can be extracted even under the condition of the fetal QRS wave being entirely overlapped with the maternal QRS wave in the abdominal composite signal. Experimental results verify the proposed method.