{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,19]],"date-time":"2025-11-19T11:39:00Z","timestamp":1763552340046,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,27]],"date-time":"2025-01-27T00:00:00Z","timestamp":1737936000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["62201098","2023KQNCX084"],"award-info":[{"award-number":["62201098","2023KQNCX084"]}]},{"name":"Young Innovative Talents Program of General Higher Education Institutions in Guangdong Province","award":["62201098","2023KQNCX084"],"award-info":[{"award-number":["62201098","2023KQNCX084"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Conventional circularly polarized antennas have been employed to deliver microwave illumination in microwave-induced thermoacoustic tomography (TAT). However, these antennas exhibit several limitations in TAT systems, including low efficiency, poor axial ratio (AR) roundness, and narrow axial ratio beamwidth (ARBW). These issues lead to uniform radiation only within a relatively confined area, thereby restricting their effectiveness in clinical applications such as breast imaging. To address these issues, we propose a novel planar slot array antenna that offers a wide ARBW and improved axial ratio (AR) roundness, enabling homogeneous illumination over a larger field. We validated this approach both theoretically and experimentally. Tissue-mimicking phantoms were imaged, demonstrating that the antenna generated a circularly polarized electric field as well as a uniformly illuminated area. These advantages make the antenna proposed in this paper more suitable for clinical imaging compared to traditional microwave radiating antennas.<\/jats:p>","DOI":"10.3390\/sym17020197","type":"journal-article","created":{"date-parts":[[2025,1,27]],"date-time":"2025-01-27T04:59:10Z","timestamp":1737953950000},"page":"197","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Novel Slot Spiral Symmetric Array Antenna with a Wide Axial Ratio Beamwidth for Microwave-Induced Thermoacoustic Tomography Applications"],"prefix":"10.3390","volume":"17","author":[{"given":"An","family":"Yan","sequence":"first","affiliation":[{"name":"School of Electronic Engineering and Intelligence, Dongguan University of Technology, Dongguan 523808, China"}]},{"given":"Yao","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Electronic Engineering and Intelligence, Dongguan University of Technology, Dongguan 523808, China"}]},{"given":"Chengxiang","family":"Gao","sequence":"additional","affiliation":[{"name":"School of Electronic Engineering and Intelligence, Dongguan University of Technology, Dongguan 523808, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0805-3524","authenticated-orcid":false,"given":"Jinghua","family":"Ye","sequence":"additional","affiliation":[{"name":"School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, China"}]},{"given":"Zengpei","family":"Zhong","sequence":"additional","affiliation":[{"name":"School of Electronic Engineering and Intelligence, Dongguan University of Technology, Dongguan 523808, China"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7087","DOI":"10.1109\/TAP.2019.2927824","article-title":"Improvement of multi-frequency microwave breast imaging through frequency cycling and tissue-dependent mapping","volume":"67","author":"Kaye","year":"2019","journal-title":"IEEE Trans. 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