Abstract:Aiming at the abdominal electrode-sourced ( AES) signals, a fetal electrocardiogram ( FECG) signal extraction method utilizing extended Kalman filter (EKF) combined with FastICA is proposed. Firstly, the raw maternal abdominal mixed signals are preprocessed to suppress baseline drift, power frequency interference and pulse artifacts. Then, FastICA is used to separate the maternal electrocardiogram (MECG) signal estimation and FECG signal estimation containing residual MECG component and other noise from maternal abdominal mixed signals. The EKF is used to filter the FECG signal estimation to obtain the residual MECG component estimation, which is suppressed to obtain the noisy FECG signal estimation. At last, the clear FECG signal is extracted using EKF again. The clinical data were adopted to verify the proposed FECG extraction method. The sensitivity, positive predictive value and F1 score of the proposed FECG extraction method are 99. 27% , 94. 35% , 96. 71% , respectively, and the signal-to-noise ratios based on cross correlation and singular value decomposition are 6. 145 4 dB and 6. 509 6 dB, respectively. The experiment results show that the proposed method is better than traditional FECG signal extraction methods both on subjective visual effect and objective assessment index