{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T18:15:28Z","timestamp":1780683328277,"version":"3.54.1"},"reference-count":44,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2024,10,2]],"date-time":"2024-10-02T00:00:00Z","timestamp":1727827200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62301262"],"award-info":[{"award-number":["62301262"]}],"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":["2022M720063"],"award-info":[{"award-number":["2022M720063"]}],"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":["BK20220440"],"award-info":[{"award-number":["BK20220440"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["62301262"],"award-info":[{"award-number":["62301262"]}],"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":["2022M720063"],"award-info":[{"award-number":["2022M720063"]}],"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":["BK20220440"],"award-info":[{"award-number":["BK20220440"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Natural Science Foundation of Jiangsu Province of China","award":["62301262"],"award-info":[{"award-number":["62301262"]}]},{"name":"Natural Science Foundation of Jiangsu Province of China","award":["2022M720063"],"award-info":[{"award-number":["2022M720063"]}]},{"name":"Natural Science Foundation of Jiangsu Province of China","award":["BK20220440"],"award-info":[{"award-number":["BK20220440"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, a complementary split-ring resonator (CSRR)-based patch antenna is proposed as a microwave sensor to measure the salt concentration of NaCl solution. The microwave sensor consists of an RF-4 substrate, where a small copper disc is attached on the top as the radiator, a larger copper disc integrated with two CSRRs is attached on the bottom side as the finite ground plane, and a coaxial feeding port is introduced at the ground plane center. During salt concentration sensing, only the top disc is immersed into NaCl solution. The results indicate that the proposed microwave sensor can measure salt concentrations ranging from 5\u2030 to 35\u2030 with a maximum sensitivity of 0.367 (kHz\/(mg\/L)). The proposed microwave sensor is low-cost, low-profile, electrically small, lightweight, and easy to fabricate, and it also can be applied to other solutions\u2019 concentration sensing.<\/jats:p>","DOI":"10.3390\/s24196389","type":"journal-article","created":{"date-parts":[[2024,10,2]],"date-time":"2024-10-02T03:57:08Z","timestamp":1727841428000},"page":"6389","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["An Electrically Small Patch Antenna Sensor for Salt Concentration Measurement of NaCl Solution"],"prefix":"10.3390","volume":"24","author":[{"given":"Jinfeng","family":"Zhu","sequence":"first","affiliation":[{"name":"Research Center of Applied Electromagnetics, Nanjing University of Information Science and Technology, Nanjing 210044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cheng","family":"Chen","sequence":"additional","affiliation":[{"name":"Research Center of Applied Electromagnetics, Nanjing University of Information Science and Technology, Nanjing 210044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2529-1145","authenticated-orcid":false,"given":"Xiao","family":"Sun","sequence":"additional","affiliation":[{"name":"School of Biological Science and Food Engineering, Chuzhou University, Chuzhou 239099, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guowen","family":"Ding","sequence":"additional","affiliation":[{"name":"Research Center of Applied Electromagnetics, Nanjing University of Information Science and Technology, Nanjing 210044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4079-7945","authenticated-orcid":false,"given":"Shenyun","family":"Wang","sequence":"additional","affiliation":[{"name":"Research Center of Applied Electromagnetics, Nanjing University of Information Science and Technology, Nanjing 210044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1038\/s41581-021-00533-0","article-title":"The impact of excessive salt intake on human health","volume":"18","author":"Hunter","year":"2022","journal-title":"Nat. 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