  In this study, an integrated low-cost and complexity mm-wave structure of
Whispering Gallery Mode (WGM) is proposed for sensing the glucose levels in
mimicking aquatic solutions of concentrations similar to type 2 diabetics. The
bio-sensor is composed of a curved dielectric waveguide coupled to a dielectric
disc resonator that is loaded with the glucose sample under test. The intense
WGM field induced towards the boundary of the DDR is exploited to detect the
slight variations in the dielectric properties of different glucose levels via
tracing the variations in the magnitude of the transmission coefficient S_{21}
in the mm-wave frequency band (49-70 GHz). The WGM resonator shows a high
sensitivity performance (0.025-0.077 dB/(mg/dL)) at the lower-order modes
WGH_{600} and WGH_{700} as demonstrated by simulations in a 3D full-wave EM
solver (Ansys HFSS).
