Patent ID: 10992050

Abstract:
Disclosed is an antenna device including a rectangular waveguide (1) having a first opening end (2a) and a second opening end (2b), a septum phase plate (3) disposed inside the rectangular waveguide (1) in such a way as to partition the first opening end (2a) into two parts along a first direction perpendicular to a waveguide axial direction of the rectangular waveguide (1), a width of the septum phase plate in a second direction perpendicular to both the waveguide axial direction of the rectangular waveguide (1) and the first direction becoming narrower stepwise with advancing from the first opening end (2a1, 2a2) toward the second opening end (2b), and first projecting portions (4a, 4b) disposed on two respective first inner walls (1a, 1b) parallel to the septum phase plate (3), out of four inner walls of the rectangular waveguide (1), in such a way as to project toward an inside of the rectangular waveguide (1).