{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T19:18:16Z","timestamp":1773775096649,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,15]],"date-time":"2023-06-15T00:00:00Z","timestamp":1686787200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Royal Academy of Engineering Industrial Fellowship","award":["IF2223-201"],"award-info":[{"award-number":["IF2223-201"]}]},{"name":"Royal Academy of Engineering Industrial Fellowship","award":["EP\/R511705\/1"],"award-info":[{"award-number":["EP\/R511705\/1"]}]},{"name":"EPSRC Research Council","award":["IF2223-201"],"award-info":[{"award-number":["IF2223-201"]}]},{"name":"EPSRC Research Council","award":["EP\/R511705\/1"],"award-info":[{"award-number":["EP\/R511705\/1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A wideband low-profile radiating G-shaped strip on a flexible substrate is proposed to operate as biomedical antenna for off-body communication. The antenna is designed to produce circular polarization over the frequency range 5\u20136 GHz to communicate with WiMAX\/WLAN antennas. Furthermore, it is designed to produce linear polarization over the frequency range 6\u201319 GHz for communication with the on-body biosensor antennas. It is shown that an inverted G-shaped strip produces circular polarization (CP) of the opposite sense to that produced by G-shaped strip over the frequency range 5\u20136 GHz. The antenna design is explained and its performance is investigated through simulation, as well as experimental measurements. This antenna can be viewed as composed of a semicircular strip terminated with a horizontal extension at its lower end and terminated with a small circular patch through a corner-shaped strip extension at its upper end to form the shape of \u201cG\u201d or inverted \u201cG\u201d. The purpose of the corner-shaped extension and the circular patch termination is to match the antenna impedance to 50 \u03a9 over the entire frequency band (5\u201319 GHz) and to improve the circular polarization over the frequency band (5\u20136 GHz). To be fabricated on only one face of the flexible dielectric substrate, the antenna is fed through a co-planar waveguide (CPW). The antenna and the CPW dimensions are optimized to obtain the most optimal performance regarding the impedance matching bandwidth, 3dB Axial Ratio (AR) bandwidth, radiation efficiency, and maximum gain. The results show that the achieved 3dB-AR bandwidth is 18% (5\u20136 GHz). Thus, the proposed antenna covers the 5 GHz frequency band of the WiMAX\/WLAN applications within its 3dB-AR frequency band. Furthermore, the impedance matching bandwidth is 117% (5\u201319 GHz) which enables low-power communication with the on-body sensors over this wide range of the frequency. The maximum gain and radiation efficiency are 5.37 dBi and 98%, respectively. The overall antenna dimensions are 25 \u00d7 27 \u00d7 0.13 mm3 and the bandwidth-dimension ratio (BDR) is 1733.<\/jats:p>","DOI":"10.3390\/s23125608","type":"journal-article","created":{"date-parts":[[2023,6,16]],"date-time":"2023-06-16T02:54:33Z","timestamp":1686884073000},"page":"5608","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Flexible Antenna with Circular\/Linear Polarization for Wideband Biomedical Wireless Communication"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8894-9525","authenticated-orcid":false,"given":"Mohammed E.","family":"Yassin","sequence":"first","affiliation":[{"name":"Electronics and Communications Engineering Department, Akhbar Elyom Academy, 6th of October City 12573, Egypt"}]},{"given":"Khaled F. A.","family":"Hussein","sequence":"additional","affiliation":[{"name":"Microwave Engineering Department, Electronics Research Institute (ERI), Cairo 11843, Egypt"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7097-9969","authenticated-orcid":false,"given":"Qammer H.","family":"Abbasi","sequence":"additional","affiliation":[{"name":"James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4743-9136","authenticated-orcid":false,"given":"Muhammad A.","family":"Imran","sequence":"additional","affiliation":[{"name":"James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4982-6471","authenticated-orcid":false,"given":"Shaimaa A.","family":"Mohassieb","sequence":"additional","affiliation":[{"name":"Electronics and Communications Engineering Department, Akhbar Elyom Academy, 6th of October City 12573, Egypt"},{"name":"James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"754","DOI":"10.1049\/mia2.12081","article-title":"Flexible circularly polarized antenna with axial ratio bandwidth enhancement for off-body communications","volume":"15","author":"Yang","year":"2021","journal-title":"IET Microwaves Antennas Propag."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2523","DOI":"10.1109\/LAWP.2019.2942147","article-title":"A compact circularly polarized antenna with directional pattern for wearable off-body communications","volume":"18","author":"Ullah","year":"2019","journal-title":"IEEE Antennas Wirel. 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