{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T17:03:51Z","timestamp":1761930231902,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2021,10,13]],"date-time":"2021-10-13T00:00:00Z","timestamp":1634083200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia (FCT)","award":["UIDB\/05583\/2020","SFRH\/BD\/139847\/2018"],"award-info":[{"award-number":["UIDB\/05583\/2020","SFRH\/BD\/139847\/2018"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Radar systems have been widely explored as a monitoring tool able to assess the subject\u2019s vital signs remotely. However, their implementation in real application scenarios is not straightforward. Received signals encompass parasitic reflections that occur in the monitoring environment. Generally, those parasitic components, often treated as a complex DC (CDC) offsets, must be removed in order to correctly extract the bio-signals information. Fitting methods can be used, but their implementation were revealed to be challenging when bio-signals are weak or when these parasitic reflections arise from non-static targets, changing the CDC offset properties over time. In this work, we propose a dynamic digital signal processing algorithm to extract the vital signs from radar systems. This algorithm includes a novel arc fitting method to estimate the CDC offsets on the received signal. The method revealed being robust to weaker signals, presenting a success rate of 95%, irrespective of the considered monitoring conditions. Furthermore, the proposed algorithm is able to adapt to slow changes in the propagation environment.<\/jats:p>","DOI":"10.3390\/rs13204079","type":"journal-article","created":{"date-parts":[[2021,10,13]],"date-time":"2021-10-13T06:38:41Z","timestamp":1634107121000},"page":"4079","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Dynamic Digital Signal Processing Algorithm for Vital Signs Extraction in Continuous-Wave Radars"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2077-2871","authenticated-orcid":false,"given":"Carolina","family":"Gouveia","sequence":"first","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"},{"name":"Departamento de Eletr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8897-9123","authenticated-orcid":false,"given":"Daniel","family":"Albuquerque","sequence":"additional","affiliation":[{"name":"Centro de Investiga\u00e7\u00e3o em Servi\u00e7os Digitais CISeD, ESTGV\u2014Polit\u00e9cnico de Viseu, 3504-510 Viseu, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4356-4522","authenticated-orcid":false,"given":"Jos\u00e9","family":"Vieira","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"},{"name":"Departamento de Eletr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5588-7794","authenticated-orcid":false,"given":"Pedro","family":"Pinho","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"},{"name":"Departamento de Engenharia Eletr\u00f3nica, Telecomunica\u00e7\u00f5es e de Computadores, Instituto Superior de Engenharia de Lisboa, 1959-007 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1530","DOI":"10.1109\/PROC.1975.9992","article-title":"Non-invasive microwave measurement of respiration","volume":"63","author":"Lin","year":"1975","journal-title":"Proc. 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