On the accuracy of complex permittivity model of glucose/water solutions for non-invasive microwave blood glucose sensing

This paper discusses the accuracy of the current complex permittivity model for binary glucose/water solutions published in the open literature. An accurate model for different concentrations of binary glucose/water solutions is needed for the simulation and validation of radio frequency (RF)/Microwave glucose sensors for the purpose of non-invasive blood glucose measurement. Most liquids can be modeled by the Cole-Cole model when several parameters are known for a specific sample. These parameters are addressed in this paper for the glucose/water solutions of 100mg/dl-500mg/dl range. An open-ended coaxial probe was manufactured for measuring the permittivity values of glucose/water solutions. The values were extracted in MATLAB from the S-parameters obtained on the Vector Network Analyzer (VNA). A new set of Debye parameters were proposed for glucose/water solutions for the frequency range of 1GHz-8GHz.