Mode-selective dielectric resonator coupled to dielectric image waveguide for sensing applications

In this paper, multi-mode dielectric resonators coupled to dielectric image waveguides are investigated for mm-wave sensing applications. It is demonstrated both numerically and experimentally that for each resonance mode, there is a critical coupling condition under which the corresponding mode will have a pronounced response with higher Q-factor compared to the other existing resonance modes. The proposed structure is attractive for sensor devices with high sensitivity, particularly because its resonance frequency can be adjusted over a wide range of millimeter-wave spectrum.