A transition of microstrip line to dielectric microstrip line for millimeter wave circuits

A compact microstrip line to dielectric microstrip line (DML) transition is investigated, where DML is a dielectric waveguide that has quasi-planar structure line like conventional microstrip. DML is much more convenient to be used for various circuit constructions, comparing to other dielectric waveguides such as non-radiative dielectric guide and image guide. However, DML is not a standard transmission line. Transition is required for the measurement. In our experiment, the measured insertion loss of a section of DML with two back-to-back transitions ranges from 3.1 dB to 5.3 dB during 42 GHz to 54 GHz.