A non-invasive monitoring system

This paper describes a preliminary study carried out using microwave resonant cavities to measure variations in blood-glucose concentrations by observing changes in Q and frequency shifts in a minima occurring in the magnitude response due to variations in the complex permittivity of the blood-glucose mixture. The measurement system presented in this work makes use of low power microwave energy over the frequency range of between 10GHz and 20GHz and resonant cavity structures. One potential future application for this work is to non-invasively monitor variations in concentrations of various constituents contained within biological fluid contained within the human biological system. The measurement data presented here was obtained using laboratory test and measurement equipment, test cells developed specifically for this study, and representative blood-glucose concentrations. The results obtained from this study indicate a variation in blood-glucose concentration representative of the normal and hyperglycaemic states causes a marked shift in the resonant frequency and the Q of the system.