Travelling-wave whispering gallery resonance sensor in millimetre-wave range

A high sensitivity sensor with a simple structure is presented for analysis of (bio)chemicals in liquid or solution form. The proposed technique is based on the travelling-wave whispering gallery resonance perturbation method in the millimetre-wave range. The resonance modes are launched inside a dielectric disk through coupling into a dielectric image waveguide. The top surface of the disk is used as the sensing area where the resonance mode interacts with the sample. Theoretical analysis and experimental results for the proposed sensor are discussed.