Microwave Planar Sensor Antenna for Glucose Sensing in Aqueous Solutions

Microwave sensing is a vastly growing sensory method that allows to reduce sensing limits in biomedical applications. In this paper, a coupled complementary split-ring resonator (CSRR) design is introduced that exploits the mutual coupling between CSRRs, thereby creating a highly sensitive region for capacitive changes. An ultra-wideband binomial slot antenna is employed to feed the coupled-CSRRs with an improved excitation signal. This technique requires phase measurement only at the single frequency of f
res
= 2.77 GHz. As a result, glucose content in water within the range of 0 – 500 mg/dL are detectable with the sensitivity better than 30 mg/dL.