Design of transition from coaxial line to ridge gap waveguide

This paper presents the design of a simple transition from ridge gap waveguide to coaxial line transition. First, a straight ridge gap waveguide with single transition on end is simulated. Then a ridge gap waveguide with two 90deg bends is simulated with two transitions on each end. Available commercial FDTD simulation tool was used to design the transitions. A return loss of -10 dB was achieved over the frequency band of 12- 15.75 GHz.