Analysis and Design of a Microwave Coplanar Sensor for Non-Invasive Blood Glucose Measurements

AVALOS RIBAS, R.; CELESTE CEBEDIO; URIZ, A. J.; GELOSI, I. E.; CASTIÑEIRA MOREIRA, J.

IEEE SENSORS JOURNAL

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Lugar: New York; Año: 2020 vol. 20 p. 10572 - 10581

1530-437X

In this paper a design for a microwave sensor forthe non-invasive measurement of blood glucose concentrationsis proposed. The sensor is intended for usage as part of anon-invasive glucose-quantifying device. With this aim, threedifferent microwave resonator structures are analyzed as possiblecandidates, and strengths and weaknesses are highlighted in eachcase. The chosen resonator is an open structure in which a fingerof the patient is placed, fulfilling the role of a sample to becharacterized by the sensor. The shape and size of the finger thuscondition those of the resonator. Variations in the concentrationof blood glucose modify the dielectric properties of the tissue,which is part of the microwave resonator-finger system, andas such, the changes translate to the resonance frequency ofthe whole structure. Among the three studied topologies, it wasfound that a single resonator designed using a coplanar structurewith a ground plane showed the best trade-off in frequencysensitivity, stability and repeatability of the measurements. Anotable correlation, between the resonance frequency of theproposed sensor and the blood glucose levels measured with atraditional glucometer, was found. This highlights a potentialinterchangeability of both glucose measurement methods.