{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,5]],"date-time":"2026-02-05T07:07:46Z","timestamp":1770275266181,"version":"3.49.0"},"reference-count":36,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,31]],"date-time":"2025-01-31T00:00:00Z","timestamp":1738281600000},"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"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>The ability to measure vital signs using electromagnetic waves has been extensively investigated as a less intrusive method capable of assessing different biosignal sources while using a single device. On-body antennas, when directly coupled to the human body, offer a comfortable and effective alternative for daily monitoring. Nonetheless, on-body antennas are challenging to design primarily due to the high dielectric constant of body tissues. While the simulation process may often include a body model, a unique model cannot account for inter-individual variability, leading to discrepancies in measured antenna parameters. A potential solution is to increase the antenna\u2019s bandwidth, guaranteeing the antenna\u2019s impedance matching and robustness for all users. This work describes a new on-body microstrip antenna having a stacked structure with parasitic elements, designed and optimized using artificial intelligence (AI). By using an AI-driven design approach, a self-adaptive Bayesian neural network surrogate-model-assisted differential evolution for antenna optimization (SB-SADEA) method to be specific, and a stacked structure having parasitic elements and a defected ground structure with 27 tuneable design parameters, the simulated impedance bandwidth of the on-body antenna was successfully enhanced from 150 MHz to 1.3 GHz, while employing a single and simplified body model in the simulation process. Furthermore, the impact of inter-individual variability on the measured S-parameters was analyzed. The measured results relative to ten subjects revealed that for certain subjects, the SB-SADEA-optimized antenna\u2019s bandwidth reached 1.6 GHz.<\/jats:p>","DOI":"10.3390\/bioengineering12020138","type":"journal-article","created":{"date-parts":[[2025,1,31]],"date-time":"2025-01-31T05:08:26Z","timestamp":1738300106000},"page":"138","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Design and Optimization of Stacked Wideband On-Body Antenna with Parasitic Elements and Defected Ground Structure for Biomedical Applications Using SB-SADEA Method"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-9607-3392","authenticated-orcid":false,"given":"Mariana","family":"Amador","sequence":"first","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Departamento de Eletr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1164-5501","authenticated-orcid":false,"given":"Mobayode O.","family":"Akinsolu","sequence":"additional","affiliation":[{"name":"Faculty of Arts, Computing and Engineering, Wrexham University, Wales LL11 2AW, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3125-9587","authenticated-orcid":false,"given":"Qiang","family":"Hua","sequence":"additional","affiliation":[{"name":"School of Computing and Engineering, University of Huddersfield, Huddersfield HD1 3DH, UK"}]},{"given":"Jo\u00e3o","family":"Cardoso","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia de Lisboa, Departamento de Engenharia Eletrot\u00e9cnica e de Computadores, 1959-007 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8897-9123","authenticated-orcid":false,"given":"Daniel","family":"Albuquerque","sequence":"additional","affiliation":[{"name":"Escola Superior de Tecnologia e Gest\u00e3o de \u00c1gueda, Universidade de Aveiro, 3750-127 \u00c1gueda, 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, Departamento de Eletr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,31]]},"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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