Optimum structural parameters of Substrate Integrated Nonradiative Dielectric waveguide for millimeter-wave applications

The maximum usable frequency of a Substrate Integrated Nonradiative Dielectric (SINRD) waveguide is determined by the following factors: parallel plate mode, next higher order mode and the appearance of bandgap effect. Parametric studies are performed to reveal the dependency of the above mentioned factors on the waveguide structural parameters. Guidelines have been formulated for the first time for proper selection of the parameters to maximize the usable frequency band with minimum propagation loss. Experimental results ~ 100 GHz are also included.