Sensitive Microfluidic Sensor With Weakly Coupled Dumbbell Defect-Ground-Structure Resonators for Volume Fraction Determination in Liquid Mixtures
Casacuberta Orta, Pau (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Vélez Rasero, Paris (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Su, Lijuan (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Canalias, Xavier (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Martín, Ferran (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)

Date:	2024
Abstract:	This letter presents a highly sensitive reflective-mode phase-variation permittivity sensor implemented by means of a pair of weakly coupled dumbbell defect-ground-structure (DB-DGS) resonators, the sensing elements, excited by a microstrip line. Weak magnetic coupling between the DB-DGS sensing resonators generates two closely spaced resonances, the separation of which can be adjusted by the coupling level. Since the phase of the reflection coefficient experiences an excursion of 360° between such frequencies, the phase slope can be made arbitrarily high. Thus, by tuning the device within that frequency range, the phase response of the sensor is highly sensitive to variations in the dielectric constant of any material surrounding the DB-DGS resonators, e. g. , a liquid under test (LUT). This configuration, with the sensing elements etched in the ground plane, avoids any interference between the driving line and the LUT, or any mechanical accessory required for operation, thereby enhancing the sensor's practical application. Specifically designed for detecting small concentration changes in mixtures of water and isopropanol, the sensor achieves a peak sensitivity of 293°/% and a resolution of less than 0. 1% with the presented setup.
Grants:	Agencia Estatal de Investigación PID2022-139181OB-I00 Agència de Gestió d'Ajuts Universitaris i de Recerca 2021/SGR-00192 Ministerio de Ciencia, Innovación y Universidades FPU20/05700 Agencia Estatal de Investigación PREP2022-000364 Agencia Estatal de Investigación RYC2022-035819-I
Note:	Altres ajuts: acords transformatius de la UAB
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Resonators ; Sensitivity ; Couplings ; Permittivity ; Microstrip ; Table lookup ; Microstrip resonators ; Integrated circuit modeling ; Sensors ; Phase measurement ; Microfluidics
Published in:	IEEE microwave and wireless technology letters, Vol. 34, Issue 12 (December 2024) , p. 1411-1414, ISSN 2771-9588

DOI: 10.1109/LMWT.2024.3475210

4 p, 7.8 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Engineering > CIMITEC-UAB
Articles > Research articles
Articles > Published articles