{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T14:54:03Z","timestamp":1773154443868,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2021,12,13]],"date-time":"2021-12-13T00:00:00Z","timestamp":1639353600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002809","name":"Government of Catalonia","doi-asserted-by":"publisher","award":["2017SGR-1159"],"award-info":[{"award-number":["2017SGR-1159"]}],"id":[{"id":"10.13039\/501100002809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003741","name":"Instituci\u00f3 Catalana de Recerca i Estudis Avan\u00e7ats","doi-asserted-by":"publisher","award":["."],"award-info":[{"award-number":["."]}],"id":[{"id":"10.13039\/501100003741","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministerio de Ciencia e Innovaci\u00f3n, Spain","award":["PID2019-103904RB-I00"],"award-info":[{"award-number":["PID2019-103904RB-I00"]}]},{"name":"Ministerio de Ciencia e Innovaci\u00f3n, Spain","award":["IJC2019-040786-I"],"award-info":[{"award-number":["IJC2019-040786-I"]}]},{"name":"European Regional Development Fund (ERDF)","award":["."],"award-info":[{"award-number":["."]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Microstrip transmission lines loaded with dumbbell defect-ground-structure (DB-DGS) resonators transversally oriented have been exhaustively used in microwave circuits and sensors. Typically, these structures have been modelled by means of a parallel LC resonant tank series connected to the host line. However, the inductance and capacitance of such model do not have a physical meaning, since this model is inferred by transformation of a more realistic model, where the DB-DGS resonator, described by means of a resonant tank with inductance and capacitance related to the geometry of the DB-DGS, is magnetically coupled to the host line. From parameter extraction, the circuit parameters of both models are obtained by considering the DB-DGS covered with semi-infinite materials with different dielectric constant. The extracted parameters are coherent and reveal that the general assumption of considering the simple LC resonant tank series-connected to the line to describe the DB-DGS-loaded line is reasonable with some caution. The implications on the sensitivity, when the structure is devoted to operating as a permittivity sensor, are discussed.<\/jats:p>","DOI":"10.3390\/s21248334","type":"journal-article","created":{"date-parts":[[2021,12,14]],"date-time":"2021-12-14T01:22:05Z","timestamp":1639444925000},"page":"8334","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Discussion and Analysis of Dumbbell Defect-Ground-Structure (DB-DGS) Resonators for Sensing Applications from a Circuit Theory Perspective"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4753-9340","authenticated-orcid":false,"given":"Lijuan","family":"Su","sequence":"first","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, 08193 Bellaterra, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6502-5987","authenticated-orcid":false,"given":"Paris","family":"V\u00e9lez","sequence":"additional","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, 08193 Bellaterra, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1271-3801","authenticated-orcid":false,"given":"Jonathan","family":"Mu\u00f1oz-Enano","sequence":"additional","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, 08193 Bellaterra, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1494-9167","authenticated-orcid":false,"given":"Ferran","family":"Mart\u00edn","sequence":"additional","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, 08193 Bellaterra, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1109\/75.846922","article-title":"A Novel 1-D Periodic Defected Ground Structure for Planar Circuits","volume":"10","author":"Kim","year":"2000","journal-title":"IEEE Microw. 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