{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T17:22:03Z","timestamp":1778692923063,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,6,17]],"date-time":"2024-06-17T00:00:00Z","timestamp":1718582400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Chosun University"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Mid-field wireless power transfer (WPT) offers a compelling solution for delivering power to miniature implantable medical devices deep within the human body. Despite its potential, the current power delivery levels remain constrained, and the design of a compact source structure to focus the transmitter field on such implants presents significant challenges. In this paper, a novel miniaturized transmitter antenna operating at 1.71 GHz is proposed. Leveraging the antenna proximity-coupled feeding technique, we achieve optimal current distribution for efficient power transfer. Additionally, a receiver integrated within the human body is proposed, comprising a slotted ground and a meandering slotted radiating element. This receiver is excited via a coaxial feedline with a truncated ground. Our findings demonstrate wireless power transfer of \u221223 dB (0.501%) at a distance of 30 mm between the transmitter and receiver, alongside a peak gain of \u221220 dB with an impedance bandwidth of 39.61%. These results highlight promising advancements in enhancing energy transfer efficiency for deep-implant applications.<\/jats:p>","DOI":"10.3390\/sym16060753","type":"journal-article","created":{"date-parts":[[2024,6,17]],"date-time":"2024-06-17T12:48:40Z","timestamp":1718628520000},"page":"753","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Design and Optimization of a Mid-Field Wireless Power Transfer System for Enhanced Energy Transfer Efficiency"],"prefix":"10.3390","volume":"16","author":[{"given":"Daud","family":"Khan","sequence":"first","affiliation":[{"name":"Communication and Wave Propagation Laboratory, Department of Information and Communication Engineering, Chosun University, Gwangju 61452, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0966-9010","authenticated-orcid":false,"given":"Ashfaq","family":"Ahmad","sequence":"additional","affiliation":[{"name":"Communication and Wave Propagation Laboratory, Department of Information and Communication Engineering, Chosun University, Gwangju 61452, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0664-7908","authenticated-orcid":false,"given":"Dong-you","family":"Choi","sequence":"additional","affiliation":[{"name":"Communication and Wave Propagation Laboratory, Department of Information and Communication Engineering, Chosun University, Gwangju 61452, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,17]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"Investigational Study for Overcoming Security Challenges in Implantable Medical Devices","volume":"16","author":"Naser","year":"2024","journal-title":"Int. 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