{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T17:53:03Z","timestamp":1770227583818,"version":"3.49.0"},"reference-count":45,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,2,22]],"date-time":"2024-02-22T00:00:00Z","timestamp":1708560000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\/Minist\u00e9rio da Ci\u00eancia, Tecnologia e Ensino Superior (MCTES)","award":["UIDB\/50008\/2020-UIDP\/50008\/2020 (IT)"],"award-info":[{"award-number":["UIDB\/50008\/2020-UIDP\/50008\/2020 (IT)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The Bio-Radar is herein presented as a non-contact radar system able to capture vital signs remotely without requiring any physical contact with the subject. In this work, the ability to use the proposed system for emotion recognition is verified by comparing its performance on identifying fear, happiness and a neutral condition, with certified measuring equipment. For this purpose, machine learning algorithms were applied to the respiratory and cardiac signals captured simultaneously by the radar and the referenced contact-based system. Following a multiclass identification strategy, one could conclude that both systems present a comparable performance, where the radar might even outperform under specific conditions. Emotion recognition is possible using a radar system, with an accuracy equal to 99.7% and an F1-score of 99.9%. Thus, we demonstrated that it is perfectly possible to use the Bio-Radar system for this purpose, which is able to be operated remotely, avoiding the subject awareness of being monitored and thus providing more authentic reactions.<\/jats:p>","DOI":"10.3390\/s24051420","type":"journal-article","created":{"date-parts":[[2024,2,22]],"date-time":"2024-02-22T08:34:35Z","timestamp":1708590875000},"page":"1420","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Remote Emotion Recognition Using Continuous-Wave Bio-Radar System"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2077-2871","authenticated-orcid":false,"given":"Carolina","family":"Gouveia","sequence":"first","affiliation":[{"name":"Instituto de Engenharia Electr\u00f3nica e Telem\u00e1tica de Aveiro, Departamento de Electr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Intelligent Systems Associate Laboratory, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Colab Almascience, Madan Parque, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8855-6323","authenticated-orcid":false,"given":"Beatriz","family":"Soares","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"},{"name":"Departamento de Electr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8897-9123","authenticated-orcid":false,"given":"Daniel","family":"Albuquerque","sequence":"additional","affiliation":[{"name":"Instituto de Engenharia Electr\u00f3nica e Telem\u00e1tica de Aveiro, Departamento de Electr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Intelligent Systems Associate Laboratory, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"},{"name":"Escola Superior de Tecnologia e Gest\u00e3o de \u00c1gueda, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4195-7805","authenticated-orcid":false,"given":"Filipa","family":"Barros","sequence":"additional","affiliation":[{"name":"Center for Health Technology and Services Research, Department of Education and Psychology, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"William James Center for Research, Department of Education and Psychology, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Sandra C.","family":"Soares","sequence":"additional","affiliation":[{"name":"William James Center for Research, Department of Education and Psychology, University of 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 Electr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4356-4522","authenticated-orcid":false,"given":"Jos\u00e9","family":"Vieira","sequence":"additional","affiliation":[{"name":"Instituto de Engenharia Electr\u00f3nica e Telem\u00e1tica de Aveiro, Departamento de Electr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Intelligent Systems Associate Laboratory, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8650-9219","authenticated-orcid":false,"given":"Susana","family":"Br\u00e1s","sequence":"additional","affiliation":[{"name":"Instituto de Engenharia Electr\u00f3nica e Telem\u00e1tica de Aveiro, Departamento de Electr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Intelligent Systems Associate Laboratory, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Boric-Lubecke, O., Lubecke, V., Droitcour, A., Park, B., and Singh, A. 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