Extracting the fetal heart rate variability using a frequency tracking algorithm

In this work, we propose an algorithm to extract the fetal heart rate variability from an ECG measured from the mother abdomen. The algorithm consists of two methods: a separation algorithm based on second-order statistics that extracts the desired signal in one shot through the data, and a heart instantaneous frequency (HIF) estimator. The HIF algorithm is used to extract the mother heart rate which serves as reference to extract the fetal heart rate. We carried out simulations where the signals overlap in frequency and time, and showed that it worked efficiently. (C) 2002 Elsevier Science B.V. All rights reserved.