Highly-sensitive microwave sensors based on open complementary split ring resonators (OCSRRs) for dielectric characterization and solute concentration measurement in liquids

Differential permittivity sensors based on a pair of uncoupled microstrip lines, each one loaded with an open complementary split ring resonator (OCSRR), are proposed in this paper. The sensing principle is based on the measurement of the cross-mode insertion loss, very sensitive to asymmetric loadi...

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Detalles Bibliográficos
Autores: Vélez, Paris|||0000-0001-6502-5987, Grenier, Katia|||0000-0002-5056-5582, Mata Contreras, Francisco Javier|||0000-0001-6116-8681, Dubuc, David, Martín, Ferran|||0000-0002-1494-9167
Tipo de recurso: artículo
Fecha de publicación:2018
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:199678
Acceso en línea:https://ddd.uab.cat/record/199678
https://dx.doi.org/urn:doi:10.1109/ACCESS.2018.2867077
Access Level:acceso abierto
Descripción
Sumario:Differential permittivity sensors based on a pair of uncoupled microstrip lines, each one loaded with an open complementary split ring resonator (OCSRR), are proposed in this paper. The sensing principle is based on the measurement of the cross-mode insertion loss, very sensitive to asymmetric loading. Thus, by loading one of the OCSRRs with the reference sample, and the other one with the sample under test (SUT), the difference in the complex permittivity between both samples generates an asymmetry that gives rise to mode conversion. From the measurement of the cross-mode transmission coefficient, the dielectric properties of the SUT can be determined, provided those of the reference sample are well known. It is shown that by adding fluidic channels on top of the OCSRRs, the proposed sensor is useful for the measurement of the complex dielectric constant of liquids, and experimental results in mixtures of ethanol and deionized (DI) water and methanol in DI water, as a function of the ethanol/methanol content, are provided. Due to the high sensitivity of the proposed differential sensor to detect small perturbations (asymmetries), the structure is also of interest for the accurate measurement of solute concentrations in liquid solutions. In this paper, the structure is applied to monitor sodium content in aqueous solutions, and it is found that sodium concentrations as small as 0.25 g/L can be resolved.