Transitions between Gap Waveguides for use in a phased array antenna fed by a Rotman lens

This paper presents two slot-coupled vertical transitions between Gap Waveguides placed in different layers; this transitions will be later used in a phased array antenna fed by a Rotman lens in the Ka band. The first proposed transition connects two ridge-gap waveguides by an H-type slot and the second transition uses a twist to connect a ridge-gap waveguide and groove-gap waveguide horizontally polarized. Results show an 11% of bandwidth for the first transition and a 2.6% of bandwidth for the second transition, which may be enough for many applications.