{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T02:11:06Z","timestamp":1774404666703,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,2,18]],"date-time":"2024-02-18T00:00:00Z","timestamp":1708214400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Microwave medical imaging (MMI) is experiencing a surge in research interest, with antenna performance emerging as a key area for improvement. This work addresses this need by enhancing the directivity of a compact UWB antenna using a Yagi-Uda-inspired reflector antenna. The proposed reflector-loaded antenna (RLA) exhibited significant gain and directivity improvements compared to a non-directional reference antenna. When analyzed for MMI applications, the RLA showed a maximum increase of 4 dBi in the realized gain and of 14.26 dB in the transmitted field strength within a human breast model. Moreover, it preserved the shape of time-domain input signals with a high correlation factor of 94.86%. To further validate our approach, another non-directional antenna with proven head imaging capabilities was modified with a reflector, achieving similar directivity enhancements. The combined results demonstrate the feasibility of RLAs for improved performance in MMI systems.<\/jats:p>","DOI":"10.3390\/s24041315","type":"journal-article","created":{"date-parts":[[2024,2,19]],"date-time":"2024-02-19T03:18:38Z","timestamp":1708312718000},"page":"1315","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["UWB Antenna with Enhanced Directivity for Applications in Microwave Medical Imaging"],"prefix":"10.3390","volume":"24","author":[{"given":"Dawar","family":"Awan","sequence":"first","affiliation":[{"name":"Department of Electrical Technology, University of Technology Nowshera, Nowshera 24170, Pakistan"},{"name":"Department of Electrical Engineering, University of Engineering and Technology Peshawar, Peshawar 25120, Pakistan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6254-7947","authenticated-orcid":false,"given":"Shahid","family":"Bashir","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, University of Engineering and Technology Peshawar, Peshawar 25120, Pakistan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4097-0928","authenticated-orcid":false,"given":"Shahid","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad 22060, Pakistan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2852-575X","authenticated-orcid":false,"given":"Samir Salem","family":"Al-Bawri","sequence":"additional","affiliation":[{"name":"Space Science Center, Institute of Climate Change, Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0369-7520","authenticated-orcid":false,"given":"Mariana","family":"Dalarsson","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, SE 100-44 Stockholm, Sweden"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"15491","DOI":"10.1038\/s41598-019-51620-z","article-title":"A low cost and portable microwave imaging system for breast tumor detection using UWB directional antenna array","volume":"9","author":"Islam","year":"2019","journal-title":"Sci. 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