{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T01:01:20Z","timestamp":1770339680866,"version":"3.49.0"},"reference-count":25,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,6,19]],"date-time":"2024-06-19T00:00:00Z","timestamp":1718755200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Xinjiang Uygur Autonomous Region Natural Science Foundation General Project","award":["2022D01C424"],"award-info":[{"award-number":["2022D01C424"]}]},{"name":"Xinjiang Uygur Autonomous Region Natural Science Foundation General Project","award":["510523005137"],"award-info":[{"award-number":["510523005137"]}]},{"name":"Xinjiang Uygur Autonomous Region Natural Science Foundation General Project","award":["62261052"],"award-info":[{"award-number":["62261052"]}]},{"name":"Xinjiang Uygur Autonomous Region Natural Science Foundation General Project","award":["620321063"],"award-info":[{"award-number":["620321063"]}]},{"name":"Xinjiang Uygur Autonomous Region Natural Science Foundation General Project","award":["2022M722962"],"award-info":[{"award-number":["2022M722962"]}]},{"name":"Tianchi Talent Project in Xinjiang Uygur Autonomous Region","award":["2022D01C424"],"award-info":[{"award-number":["2022D01C424"]}]},{"name":"Tianchi Talent Project in Xinjiang Uygur Autonomous Region","award":["510523005137"],"award-info":[{"award-number":["510523005137"]}]},{"name":"Tianchi Talent Project in Xinjiang Uygur Autonomous Region","award":["62261052"],"award-info":[{"award-number":["62261052"]}]},{"name":"Tianchi Talent Project in Xinjiang Uygur Autonomous Region","award":["620321063"],"award-info":[{"award-number":["620321063"]}]},{"name":"Tianchi Talent Project in Xinjiang Uygur Autonomous Region","award":["2022M722962"],"award-info":[{"award-number":["2022M722962"]}]},{"name":"National Natural Science Foundation of China","award":["2022D01C424"],"award-info":[{"award-number":["2022D01C424"]}]},{"name":"National Natural Science Foundation of China","award":["510523005137"],"award-info":[{"award-number":["510523005137"]}]},{"name":"National Natural Science Foundation of China","award":["62261052"],"award-info":[{"award-number":["62261052"]}]},{"name":"National Natural Science Foundation of China","award":["620321063"],"award-info":[{"award-number":["620321063"]}]},{"name":"National Natural Science Foundation of China","award":["2022M722962"],"award-info":[{"award-number":["2022M722962"]}]},{"name":"Xinjiang University Youth Doctoral Research Launch Project","award":["2022D01C424"],"award-info":[{"award-number":["2022D01C424"]}]},{"name":"Xinjiang University Youth Doctoral Research Launch Project","award":["510523005137"],"award-info":[{"award-number":["510523005137"]}]},{"name":"Xinjiang University Youth Doctoral Research Launch Project","award":["62261052"],"award-info":[{"award-number":["62261052"]}]},{"name":"Xinjiang University Youth Doctoral Research Launch Project","award":["620321063"],"award-info":[{"award-number":["620321063"]}]},{"name":"Xinjiang University Youth Doctoral Research Launch Project","award":["2022M722962"],"award-info":[{"award-number":["2022M722962"]}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["2022D01C424"],"award-info":[{"award-number":["2022D01C424"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["510523005137"],"award-info":[{"award-number":["510523005137"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["62261052"],"award-info":[{"award-number":["62261052"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["620321063"],"award-info":[{"award-number":["620321063"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["2022M722962"],"award-info":[{"award-number":["2022M722962"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This research proposes a miniature circular polarization antenna used in a wireless capsule endoscopy system at 2.45 GHz for industrial, scientific, and medical bands. We propose a method of cutting a chamfer rectangular slot on a circular radiation patch and introducing a curved radiation structure into the centerline position of the chamfer rectangular slot, while a short-circuit probe is added to achieve miniaturization. Therefore, we significantly reduced the size of the antenna and made it exhibit circularly polarized radiation characteristics. A cross-slot is cut in the GND to enable the antenna to better cover the operating band while being able to meet the complex human environment. The effective axis ratio bandwidth is 120 MHz (2.38\u20132.50 GHz). Its size is \u03c0 \u00d7 0.032\u03bb02 \u00d7 0.007\u03bb0 (where \u03bb0 is the free-space wavelength of at 2.4 GHz). In addition, the effect of different organs such as muscle, stomach, small intestine, and big intestine on the antenna when it was embedded into the wireless capsule endoscopy (WCE) system was further discussed, and the results proved that the WCE system has better robustness in different organs. The antenna\u2019s specific absorption rate can follow the IEEE Standard Safety Guidelines (IEEE C95.1-1999). A prototype is fabricated and measured. The experimental results are consistent with the simulation results.<\/jats:p>","DOI":"10.3390\/s24123960","type":"journal-article","created":{"date-parts":[[2024,6,19]],"date-time":"2024-06-19T08:06:06Z","timestamp":1718784366000},"page":"3960","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Design of a Compact Circularly Polarized Implantable Antenna for Capsule Endoscopy Systems"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3535-5827","authenticated-orcid":false,"given":"Zhiwei","family":"Song","sequence":"first","affiliation":[{"name":"The School of Electrical Engineering, Xinjiang University, Huarui Street 777#, Shuimogou District, Urumqi 830047, China"}]},{"given":"Xiaoming","family":"Xu","sequence":"additional","affiliation":[{"name":"The School of Electrical Engineering, Xinjiang University, Huarui Street 777#, Shuimogou District, Urumqi 830047, China"}]},{"given":"Youwei","family":"Shi","sequence":"additional","affiliation":[{"name":"The School of Electrical Engineering, Xinjiang University, Huarui Street 777#, Shuimogou District, Urumqi 830047, China"}]},{"given":"Lu","family":"Wang","sequence":"additional","affiliation":[{"name":"The 58th Research Institute of China Electronics Technology Group Corporation, Wuxi 214072, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1109\/RBME.2011.2171182","article-title":"Capsule Endoscopy: From Current Achievements to Open Challenges","volume":"4","author":"Ciuti","year":"2011","journal-title":"IEEE Rev. 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