Single-frequency amplitude-modulation sensor for dielectric characterization of solids and microfluidics
Vélez Rasero, Paris (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Muñoz Enano, Jonathan (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Ebrahimi, Amir (Royal Melbourne Institute of Technology. School of Engineering)
Herrojo, Cristian (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Paredes, Ferran (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Scott, James (Royal Melbourne Institute of Technology. School of Engineering)
Ghorbani, Kamran (Royal Melbourne Institute of Technology. School of Engineering)
Martín, Ferran (Martín Antolín) (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)

Date:	2021
Abstract:	A microfluidic sensor based on a microstrip line loaded with a composite resonator is reported in this paper. The composite resonator combines a shunt connected step impedance resonator (SIR) and a complementary split ring resonator CSRR) etched in the ground plane. By etching the CSRR beneath the patch of the SIR, the composite CSRR-loaded SIR resonator exhibits two transmission zeros and a pole in between. The operating principle of the sensor is the variation of the transmission coefficient at the pole frequency of the bare resonator, when a material or liquid under test (LUT) is in contact with the CSRR (the sensitive element). By designing the CSRR-loaded SIR resonator with closely spaced pole and transmission zeros, highly sensitive sensors are obtained. Despite the fact that the proposed sensor can also operate as a frequency variation sensor, using it as a single-frequency sensor based on the variation of the transmission coefficient (caused by the LUT) at a specific frequency reduces sensor costs. The reason is that a harmonic signal injected to the input port of the microstrip-based sensor plus a simple amplitude modulation (AM) detector (connected to the output port) suffices for measuring purposes. The proposed microfluidic sensor is applied to the characterization of volume fraction of solutions of isopropanol in deionized (DI) water. The sensor is able to resolve volume fractions as small as 5%, and the maximum measured sensitivity is as good as 4 mV/%.
Grants:	Agencia Estatal de Investigación TEC2016-75650-R Agencia Estatal de Investigación PID2019-103904RB-I00 Agencia Estatal de Investigación IJCI-2017-31339 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-1159
Note:	Altres ajuts: ICREA award
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	Complementary split ring resonator (CSRR) ; Microfluidics ; Microstrip technology ; Microwave sensors ; Permittivity measurements ; Step impedance resonator (SIR)
Published in:	IEEE sensors journal, Vol. 21, Issue 10 (May 2021) , p. 12189-12201, ISSN 1558-1748

DOI: 10.1109/JSEN.2021.3062290

Postprint 14 p, 2.2 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Engineering > CIMITEC-UAB
Articles > Research articles
Articles > Published articles