{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T11:10:00Z","timestamp":1772622600581,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,2,18]],"date-time":"2022-02-18T00:00:00Z","timestamp":1645142400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"H2020\/2014-2020","award":["H2020-ECSEL-2019-IA-876190,"],"award-info":[{"award-number":["H2020-ECSEL-2019-IA-876190,"]}]},{"name":"PT2020","award":["UID\/EEA\/50008\/2020"],"award-info":[{"award-number":["UID\/EEA\/50008\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>In this paper, we present the design of a compact and highly sensitive microwave sensor based on a metamaterial complementary split-ring resonator (CSRR), for liquid characterization at microwave frequencies. The design consists of a two-port microstrip-fed rectangular patch resonating structure printed on a 20 \u00d7 28 mm2 Roger RO3035 substrate with a thickness of 0.75 mm, a relative permittivity of 3.5, and a loss tangent of 0.0015. A CSRR is etched on the ground plane for the purpose of sensor miniaturization. The investigated liquid sample is put in a capillary glass tube lying parallel to the surface of the sensor. The parallel placement of the liquid test tube makes the design twice as efficient as a normal one in terms of sensitivity and Q factor. By bending the proposed structure, further enhancements of the sensor design can be obtained. These changes result in a shift in the resonant frequency and Q factor of the sensor. Hence, we could improve the sensitivity 10-fold compared to the flat structure. Subsequently, two configurations of sensors were designed and tested using CST simulation software, validated using HFSS simulation software, and compared to structures available in the literature, obtaining good agreement. A prototype of the flat configuration was fabricated and experimentally tested. Simulation results were found to be in good agreement with the experiments. The proposed devices exhibit the advantage of exploring multiple rapid and easy measurements using different test tubes, making the measurement faster, easier, and more cost-effective; therefore, the proposed high-sensitivity sensors are ideal candidates for various sensing applications.<\/jats:p>","DOI":"10.3390\/app12042144","type":"journal-article","created":{"date-parts":[[2022,2,21]],"date-time":"2022-02-21T08:14:46Z","timestamp":1645431286000},"page":"2144","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Compact and Highly Sensitive Bended Microwave Liquid Sensor Based on a Metamaterial Complementary Split-Ring Resonator"],"prefix":"10.3390","volume":"12","author":[{"given":"Said","family":"Mosbah","sequence":"first","affiliation":[{"name":"Laboratoire d\u2019Electronique de Puissance et Commande Industrielle (LEPCI), Department of Electronics, University of Ferhat Abbas, S\u00e9tif -1-, S\u00e9tif 19000, Algeria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9803-9346","authenticated-orcid":false,"given":"Chemseddine","family":"Zebiri","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Electronique de Puissance et Commande Industrielle (LEPCI), Department of Electronics, University of Ferhat Abbas, S\u00e9tif -1-, S\u00e9tif 19000, Algeria"}]},{"given":"Djamel","family":"Sayad","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Electrotechnique de Skikda (LES), Department of Electrical Engineering, University 20 Aout 1955-Skikda, Skikda 21000, Algeria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0440-8025","authenticated-orcid":false,"given":"Issa","family":"Elfergani","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"},{"name":"Faculty of Engineering and Informatics, University of Bradford, Bradford BD7 1DP, UK"}]},{"given":"Mohamed Lamine","family":"Bouknia","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Electronique de Puissance et Commande Industrielle (LEPCI), Department of Electronics, University of Ferhat Abbas, S\u00e9tif -1-, S\u00e9tif 19000, Algeria"}]},{"given":"Samira","family":"Mekki","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Electronique de Puissance et Commande Industrielle (LEPCI), Department of Electronics, University of Ferhat Abbas, S\u00e9tif -1-, S\u00e9tif 19000, Algeria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8742-4716","authenticated-orcid":false,"given":"Rami","family":"Zegadi","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Electronique de Puissance et Commande Industrielle (LEPCI), Department of Electronics, University of Ferhat Abbas, S\u00e9tif -1-, S\u00e9tif 19000, Algeria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3487-2467","authenticated-orcid":false,"given":"Merih","family":"Palandoken","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronics Engineering, Izmir Katip Celebi University, No:33\/2, Izmir 35620, Turkey"}]},{"given":"Jonathan","family":"Rodriguez","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2972-9965","authenticated-orcid":false,"given":"Raed A.","family":"Abd-Alhameed","sequence":"additional","affiliation":[{"name":"Faculty of Engineering and Informatics, University of Bradford, Bradford BD7 1DP, UK"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,18]]},"reference":[{"key":"ref_1","first-page":"13","article-title":"3-D Terrains Deployment of Wireless Sensors Network by Utilizing Parallel Gases Brownian Motion Optimization","volume":"22","author":"Gao","year":"2021","journal-title":"J. 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