Microwave sensor for non-invasive glucose measurements design and implementation of a novel linear

In this paper, a novel non-invasive sensor for the measurement of the glucose concentrations in blood is presented. By using a microstrip band pass filter, a wireless sensor is achieved. In the introduced design, the thumb is placed on the structure of the filter as a superstrate. The response of the filter is dependent on the permittivity of the superstrate. A compact size, linearity and cost effectiveness are the most important advantages of the proposed sensor. The linear behaviour of the filter in terms of the frequency is investigated and for a linear behaviour, a certain frequency for operation is selected. The introduced sensor can be used by diabetics for continuous self-monitoring of the glucose level. The structure of the proposed sensor is designed on the low-cost substrate, FR4, by compact dimensions of 50 mm x 40 mm x 1.6 mm. A prototype of the proposed filter was fabricated and the performance of the filter was investigated, experimentally.