Ridge waveguide to a partial H-plane waveguide transition

A waveguide transition comprising a ridge waveguide section that in turn comprises a first ridge part running along a first wall in the ridge waveguide section, where there is a first distance between the first wall and an opposing second wall, wherein the waveguide transition comprises a partial H-plane waveguide section that in turn comprises at least one electrically conducting foil arranged inside the partial H-plane waveguide section and comprising a longitudinally running foil slot ending a certain edge distance before a foil edge that faces the ridge waveguide section, where the ridge waveguide section and the partial H-plane waveguide section overlap at a transition section that has a first end at a transition between the second wall and a third wall, the third wall being parallel to the second wall, where there is a second distance between the first wall and the third wall that exceeds the first distance, and where the transition section has a second end where the first ridge part ends by a transversely running second ridge part that crosses the foil slot and connects to the third wall, perpendicular to the first wall.