Design Strategy of Microwave Resonant Sensors with Stable Response for Blood Glucose Monitoring

Microwave signals have gained significant interest for emerging medical applications. An example includes blood glucose monitoring where the complex scenario can compromise an accurate sensing, due to a number of factors, such as system noise, environmental temperature, and all those factors affecting the dielectric properties of tissues (e.g., variation across people). In order to mitigate such a drawback, a modified patch resonator (2.3 GHz) with a solid "matching layer" interposed between a traditional microstrip antenna and the phantom under test, is presented. Numerical results confirm this solution allows to achieve a good trade-off between measurement stability and sensitivity, allowing to discriminate glucose concentrations in a broad range from 100 up to 350 mg/dL.