{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T03:23:17Z","timestamp":1768965797427,"version":"3.49.0"},"reference-count":36,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,5]],"date-time":"2023-09-05T00:00:00Z","timestamp":1693872000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Commission","award":["813483"],"award-info":[{"award-number":["813483"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Unobtrusive monitoring of children\u2019s heart rate (HR) and respiratory rate (RR) can be valuable for promoting the early detection of potential health issues, improving communication with healthcare providers and reducing unnecessary hospital visits. A promising solution for wireless vital sign monitoring is radar technology. This paper presents a novel approach for the simultaneous estimation of children\u2019s RR and HR utilizing ultra-wideband (UWB) radar using a deep transfer learning algorithm in a cohort of 55 children. The HR and RR are calculated by processing radar signals via spectrogram from time epochs of 10 s (25 sample length of hamming window with 90% overlap) and then transforming the resultant representation into 2-dimensional images. These images were fed into a pre-trained Visual Geometry Group-16 (VGG-16) model (trained on ImageNet dataset), with weights of five added layers fine-tuned using the proposed data. The prediction on the test data achieved a mean absolute error (MAE) of 7.3 beats per minute (BPM &lt; 6.5% of average HR) and 2.63 breaths per minute (BPM &lt; 7% of average RR). We also achieved a significant Pearson\u2019s correlation of 77% and 81% between true and extracted for HR and RR, respectively. HR and RR samples are extracted every 10 s.<\/jats:p>","DOI":"10.3390\/s23187665","type":"journal-article","created":{"date-parts":[[2023,9,5]],"date-time":"2023-09-05T10:26:43Z","timestamp":1693909603000},"page":"7665","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Ultra-Wideband Radar for Simultaneous and Unobtrusive Monitoring of Respiratory and Heart Rates in Early Childhood: A Deep Transfer Learning Approach"],"prefix":"10.3390","volume":"23","author":[{"given":"Emad","family":"Arasteh","sequence":"first","affiliation":[{"name":"Department of Neonatology, University Medical Center Utrecht, Wilhelmina Children\u2019s Hospital, 3508 EA Utrecht, The Netherlands"},{"name":"Department of Electrical Engineering (ESAT), STADIUS Center for Dynamical Systems, Signal Processing and Data Analytics, KU Leuven, 3001 Leuven, Belgium"}]},{"given":"Esther S.","family":"Veldhoen","sequence":"additional","affiliation":[{"name":"Pediatric Intensive Care Unit and Center of Home Mechanical Ventilation, University Medical Center Utrecht, Wilhelmina Children\u2019s Hospital, 3508 EA Utrecht, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9505-1270","authenticated-orcid":false,"given":"Xi","family":"Long","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Eindhoven University of Technology, 5612 AE Eindhoven, The Netherlands"}]},{"given":"Maartje","family":"van Poppel","sequence":"additional","affiliation":[{"name":"Pediatric Intensive Care Unit and Center of Home Mechanical Ventilation, University Medical Center Utrecht, Wilhelmina Children\u2019s Hospital, 3508 EA Utrecht, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-0583-2745","authenticated-orcid":false,"given":"Marjolein","family":"van der Linden","sequence":"additional","affiliation":[{"name":"Department of Neonatology, University Medical Center Utrecht, Wilhelmina Children\u2019s Hospital, 3508 EA Utrecht, The Netherlands"}]},{"given":"Thomas","family":"Alderliesten","sequence":"additional","affiliation":[{"name":"Department of Neonatology, University Medical Center Utrecht, Wilhelmina Children\u2019s Hospital, 3508 EA Utrecht, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9843-0740","authenticated-orcid":false,"given":"Joppe","family":"Nijman","sequence":"additional","affiliation":[{"name":"Pediatric Intensive Care Unit and Center of Home Mechanical Ventilation, University Medical Center Utrecht, Wilhelmina Children\u2019s Hospital, 3508 EA Utrecht, The Netherlands"}]},{"given":"Robbin","family":"de Goederen","sequence":"additional","affiliation":[{"name":"Department of Neonatology, University Medical Center Utrecht, Wilhelmina Children\u2019s Hospital, 3508 EA Utrecht, The Netherlands"}]},{"given":"Jeroen","family":"Dudink","sequence":"additional","affiliation":[{"name":"Department of Neonatology, University Medical Center Utrecht, Wilhelmina Children\u2019s Hospital, 3508 EA Utrecht, The Netherlands"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"104321","DOI":"10.1016\/j.compbiomed.2021.104321","article-title":"Non-contact breathing rate monitoring in newborns: A review","volume":"132","author":"Maurya","year":"2021","journal-title":"Comput. 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