{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T16:57:20Z","timestamp":1790614640093,"version":"4.1.0"},"reference-count":45,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T00:00:00Z","timestamp":1790380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000266","name":"UK Engineering and Physical Sciences Research Council","doi-asserted-by":"publisher","award":["EP\/X039366\/1"],"award-info":[{"award-number":["EP\/X039366\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"award":["EP\/X039366\/1"],"award-info":[{"award-number":["EP\/X039366\/1"]}],"id":[{"id":"https:\/\/ror.org\/0439y7842","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Marie Sk\u0142odowska-Curie, Research and Innovation Staff Exchange","award":["101086492"],"award-info":[{"award-number":["101086492"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents the systematic design, equivalent circuit analysis, and experimental validation of a compact wideband circular microstrip patch antenna for use in biomedical telemetry. The antenna, loaded with interdigital capacitive slots and a defected patch structure (DPS), was fabricated on a Rogers RO3006 substrate (relative permittivity 6.5, loss tangent 0.002, thickness 0.8 mm) with overall dimensions of 25 \u00d7 36.96 mm2. A stepwise design evolution through five variants (ANT1\u2013ANT5) illustrates the progressive bandwidth enhancement mechanisms. The final design (ANT5) achieved a simulated \u221210 dB impedance bandwidth of 1.50 GHz (2.51\u20134.01 GHz), corresponding to a fractional bandwidth of 46%. The fabricated prototype exhibited a measured \u221210 dB bandwidth of 1.42 GHz (2.54\u20133.96 GHz), representing a fractional bandwidth of 43.7%. An equivalent lumped-element circuit model was derived and validated against the full-wave simulation results. The antenna exhibited a simulated peak free-space gain of 3.2 dBi at 3.8 GHz, with free-space radiation efficiency exceeding 90%. Under multi-layer tissue phantom loading, the antenna maintained a robust 910 MHz operational bandwidth with a safe maximum specific absorption rate (SAR) of 0.724 W\/kg and an on-body efficiency of 8.4%. The compact size and wide fractional bandwidth provide enhanced resilience against environmental detuning, making this design particularly suitable for robust wearable biomedical telemetry.<\/jats:p>","DOI":"10.3390\/s26196117","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T15:57:57Z","timestamp":1790611077000},"page":"6117","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Detuning-Resilient Wideband Microstrip Antenna for Wearable Biomedical Telemetry Through Progressive Interdigital Slot Integration and Patch Defect Engineering"],"prefix":"10.3390","volume":"26","author":[{"given":"Prince O.","family":"Siaw","sequence":"first","affiliation":[{"name":"Institute of Digital and Sustainable Futures, University of Bradford, Bradford BD7 1DP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-3773-3150","authenticated-orcid":false,"given":"Ebenezer","family":"Adjei","sequence":"additional","affiliation":[{"name":"Institute of Digital and Sustainable Futures, University of Bradford, Bradford BD7 1DP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmad","family":"Aldelemy","sequence":"additional","affiliation":[{"name":"Institute of Digital and Sustainable Futures, University of Bradford, Bradford BD7 1DP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4085-4743","authenticated-orcid":false,"given":"John G.","family":"Buckley","sequence":"additional","affiliation":[{"name":"Management, Sciences and Engineering, University of Bradford, Bradford BD7 1DP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2972-9965","authenticated-orcid":false,"given":"Raed","family":"Abd-Alhameed","sequence":"additional","affiliation":[{"name":"Management, Sciences and Engineering, University of Bradford, Bradford BD7 1DP, UK"},{"name":"Department of Information and Communication Engineering, Alfarqadein University, Basrah 61004, Iraq"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,26]]},"reference":[{"key":"ref_1","unstructured":"Balanis, C.A. 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