The Addition of Adaptive Comb Filtering to Sequential Adaptive Processing for Fetal Electrocardiograms (ECGs)

Previously published results demonstrated that a sequential combination of adaptive linear prediction (LPC), adaptive noise cancellation (ANC), and non-adaptive (fixed) IIR comb filtering (CF) can effectively remove maternal interference from noninvasive fetal ECGs. This paper presents results obtained by replacing the third stage fixed IIR comb filtering (CF) with adaptive comb filtering (ACF). In this work the fixed IIR comb filtering is replaced by an FIR adaptive comb filtering based on two distinct forms of the ACF adaptive algorithms. Experimental results illustrate that sequential LPC-ANC processing followed by the newly proposed adaptive comb filtering is an effective form of sequential processing.