A High-Sensitivity Cylindrical Cavity Resonator Sensor for the Characterization of Aqueous Solutions

AVALOS RIBAS, R.; GELOSI, I. E.; URIZ, A. J.; CASTIÑEIRA MOREIRA, J.; BONADERO, J. C.

IEEE SENSORS JOURNAL

Institute of Electrical and Electronics Engineers Inc.

Año: 2021 vol. 21 p. 7581 - 7589

1530-437X

—In this paper, a high sensitivity concentrationsensor for aqueous solutions is presented. The device isa cylindrical cavity resonator operating around a frequencyof 1.5 gigahertz. The measurement procedure is simple,instantaneous,non-destructive,and obtains information fromtwo different resonance parameters (frequency and amplitude). Samples are introduced via small, standard test tubes,and a very small amount (aroundfour milliliters) is sufficienttoperform a measurement. The design is first approached froma theoretical perspective, after which, empirical adjustmentsare paired with a simulation-based design optimization. Theresulting topology is constructed, showing agreement withsaid simulations. The final sensor can be used, after a regression type calibration, to indirectly measure the concentration of a liquid solution of known components. The experimentalvalidation,employingdifferentmixtures, demonstrates thatthe proposeddevice shows an enhancedsensitivityto solutionconcentration when compared to other resonator-based arrangements found in the literature.