{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T19:06:32Z","timestamp":1773255992004,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,20]],"date-time":"2024-08-20T00:00:00Z","timestamp":1724112000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Shuimu Tsinghua Scholar Program of Tsinghua University","award":["2023SM057"],"award-info":[{"award-number":["2023SM057"]}]},{"name":"Shuimu Tsinghua Scholar Program of Tsinghua University","award":["61971263"],"award-info":[{"award-number":["61971263"]}]},{"name":"Shuimu Tsinghua Scholar Program of Tsinghua University","award":["62171259"],"award-info":[{"award-number":["62171259"]}]},{"name":"Shuimu Tsinghua Scholar Program of Tsinghua University","award":["764479"],"award-info":[{"award-number":["764479"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2023SM057"],"award-info":[{"award-number":["2023SM057"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61971263"],"award-info":[{"award-number":["61971263"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62171259"],"award-info":[{"award-number":["62171259"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["764479"],"award-info":[{"award-number":["764479"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Institute for Precision Medicine of Tsinghua University","award":["2023SM057"],"award-info":[{"award-number":["2023SM057"]}]},{"name":"Institute for Precision Medicine of Tsinghua University","award":["61971263"],"award-info":[{"award-number":["61971263"]}]},{"name":"Institute for Precision Medicine of Tsinghua University","award":["62171259"],"award-info":[{"award-number":["62171259"]}]},{"name":"Institute for Precision Medicine of Tsinghua University","award":["764479"],"award-info":[{"award-number":["764479"]}]},{"name":"Department of Electronic Engineering of Tsinghua University","award":["2023SM057"],"award-info":[{"award-number":["2023SM057"]}]},{"name":"Department of Electronic Engineering of Tsinghua University","award":["61971263"],"award-info":[{"award-number":["61971263"]}]},{"name":"Department of Electronic Engineering of Tsinghua University","award":["62171259"],"award-info":[{"award-number":["62171259"]}]},{"name":"Department of Electronic Engineering of Tsinghua University","award":["764479"],"award-info":[{"award-number":["764479"]}]},{"name":"EMERALD Project funded by the European Union Horizon 2020 Research and Innovation Program through the Marie Sklodowska-Curie","award":["2023SM057"],"award-info":[{"award-number":["2023SM057"]}]},{"name":"EMERALD Project funded by the European Union Horizon 2020 Research and Innovation Program through the Marie Sklodowska-Curie","award":["61971263"],"award-info":[{"award-number":["61971263"]}]},{"name":"EMERALD Project funded by the European Union Horizon 2020 Research and Innovation Program through the Marie Sklodowska-Curie","award":["62171259"],"award-info":[{"award-number":["62171259"]}]},{"name":"EMERALD Project funded by the European Union Horizon 2020 Research and Innovation Program through the Marie Sklodowska-Curie","award":["764479"],"award-info":[{"award-number":["764479"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper demonstrates the design steps of a slot-loaded Vivaldi antenna for biomedical microwave imaging applications, showing the influence of the design parameters on the antenna\u2019s dimensions and performances. Several antenna miniaturization techniques were taken into consideration during the design: reduction in the electromagnetic wavelength by using a high-permittivity substrate material (relative permittivity \u03f5r=10.2), the placement of the antenna inside a coupling medium (\u03f5r=23), and the elongation of the current path by etching slots on each side of the radiator to reduce the antenna\u2019s lowest resonant frequency without increasing its physical dimensions. Moreover, an analysis of different antenna slot design scenarios was performed considering different slot lengths, inclination angles, positions, and numbers. Considering the frequency range of microwave imaging (i.e., about 500 MHz\u20135 GHz) and the array arrangement typical of microwave imaging, the best design was chosen. Finally, the antenna was fabricated and its performances in the coupling medium were characterized. The simulation and measurement results showed good agreement between each other. In comparison with literature antennas, the one developed in this work shows wide bandwidth and compact dimensions.<\/jats:p>","DOI":"10.3390\/s24165368","type":"journal-article","created":{"date-parts":[[2024,8,20]],"date-time":"2024-08-20T06:07:35Z","timestamp":1724134055000},"page":"5368","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Slot-Loaded Vivaldi Antenna for Biomedical Microwave Imaging Applications: Influence of Design Parameters on Antenna\u2019s Dimensions and Performances"],"prefix":"10.3390","volume":"24","author":[{"given":"Mengchu","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Electronic Engineering, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2498-3219","authenticated-orcid":false,"given":"Lorenzo","family":"Crocco","sequence":"additional","affiliation":[{"name":"CNR-IREA National Research Council of Italy, Institute for Electromagnetic Sensing of the Environment, 80124 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7258-6413","authenticated-orcid":false,"given":"Maokun","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7624-1113","authenticated-orcid":false,"given":"Marta","family":"Cavagnaro","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, Electronics, and Telecommunications, University of Rome \u201cLa Sapienza\u201d, 00184 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Persico, R. 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