{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T00:50:59Z","timestamp":1775609459736,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,4,5]],"date-time":"2022-04-05T00:00:00Z","timestamp":1649116800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["1917105"],"award-info":[{"award-number":["1917105"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["OD024874"],"award-info":[{"award-number":["OD024874"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The UC Irvine\u2019s Beall Applied Innovation","award":["Proof of Product (POP) Grant"],"award-info":[{"award-number":["Proof of Product (POP) Grant"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Fetal electrocardiogram (fECG) assessment is essential throughout pregnancy to monitor the wellbeing and development of the fetus, and to possibly diagnose potential congenital heart defects. Due to the high noise incorporated in the abdominal ECG (aECG) signals, the extraction of fECG has been challenging. And it is even a lot more difficult for fECG extraction if only one channel of aECG is provided, i.e., in a compact patch device. In this paper, we propose a novel algorithm based on the Ensemble Kalman filter (EnKF) for non-invasive fECG extraction from a single-channel aECG signal. To assess the performance of the proposed algorithm, we used our own clinical data, obtained from a pilot study with 10 subjects each of 20 min recording, and data from the PhysioNet 2013 Challenge bank with labeled QRS complex annotations. The proposed methodology shows the average positive predictive value (PPV) of 97.59%, sensitivity (SE) of 96.91%, and F1-score of 97.25% from the PhysioNet 2013 Challenge bank. Our results also indicate that the proposed algorithm is reliable and effective, and it outperforms the recently proposed extended Kalman filter (EKF) based algorithm.<\/jats:p>","DOI":"10.3390\/s22072788","type":"journal-article","created":{"date-parts":[[2022,4,5]],"date-time":"2022-04-05T11:26:07Z","timestamp":1649157967000},"page":"2788","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Fetal Electrocardiogram Extraction from the Mother\u2019s Abdominal Signal Using the Ensemble Kalman Filter"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3177-2770","authenticated-orcid":false,"given":"Sadaf","family":"Sarafan","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering and Computer Science, University of California Irvine, Irvine, CA 92697, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1845-0064","authenticated-orcid":false,"given":"Tai","family":"Le","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Computer Science, University of California Irvine, Irvine, CA 92697, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael P. H.","family":"Lau","sequence":"additional","affiliation":[{"name":"Sensoriis, Inc., Edmonds, WA 98026, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Afshan","family":"Hameed","sequence":"additional","affiliation":[{"name":"Obstetrics & Gynecology, Medical Center, University of California Irvine, Irvine, CA 92868, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tadesse","family":"Ghirmai","sequence":"additional","affiliation":[{"name":"Division of Engineering and Mathematics, Bothell Campus, University of Washington, Bothell, WA 98026, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4197-7208","authenticated-orcid":false,"given":"Hung","family":"Cao","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Computer Science, University of California Irvine, Irvine, CA 92697, USA"},{"name":"Department of Biomedical Engineering, University of California Irvine, Irvine, CA 92617, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,5]]},"reference":[{"key":"ref_1","unstructured":"Gregory, E.C. 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