Noninvasive Method for Measuring the Blood Glucose Level Using a Narrow Band Microstrip Antenna

Abstract

In this paper, a narrowband and compact antenna resonating at 6.1 GHz with a peak realized gain of 3.3 dBi is proposed to monitor the glucose concentration in the blood without taking invasive blood samples. The proposed antenna is fabricated using a low-cost FR-4 substrate with compact dimensions of 30 mm × 30 mm × 1.6 mm. The impedance bandwidth of this antenna ranges from 5.2 to 7.1 GHz. For measuring blood glucose levels, a human finger phantom model with dimensions of 15 mm × 12 mm × 10 mm is constructed using the EM simulation (HFSS) environment. The finger phantom consists of different layers such as skin, fat, muscle, blood, and bone modeled at 6.1 GHz using various dielectric materials for various glucose concentrations. The finger phantom model is placed at different locations around the antenna to measure the frequency shift for monitoring glucose concentration in blood samples. The proposed finger phantom model is validated by conducting an experimental study by placing a real human finger around the fabricated antenna and measuring the frequency shift. This study shows a very good agreement with the results obtained by the simulated phantom model. The advantages and outperformance of the proposed sensor are highlighted in terms of the sensitivity obtained and compared with other techniques given in the literature.