The
waveguide-
microstrip conversion device comprises a
dielectric substrate, a first grounding layer and a second grounding layer are arranged on the upper surface and the lower surface of the
dielectric substrate respectively, a rectangular
waveguide is arranged on the first grounding layer, a window is formed in the narrow wall of one side of the rectangular
waveguide, a
metal patch is arranged in the first grounding layer, and the
metal patch is arranged in the second grounding layer. The
metal patch comprises an L-shaped short-circuit stub and a reconfigurable grounding metal
gasket, the upper surface of the
dielectric substrate is provided with a
microstrip line, the
microstrip line is connected with the L-shaped short-circuit stub through a window and feeds power to the L-shaped short-circuit stub, and the reconfigurable grounding metal
gasket is connected with the second grounding layer; and double-
ridge waveguide
impedance transformer structures are arranged on the L-shaped short-circuit
branch knots and the reconfigurable grounding metal gaskets. The ground structure at the
tail end of the micro-strip
transmission line is reconstructed to be combined with the double-
ridge waveguide
impedance transformer, good matching of an
electric field and impedance is achieved at the same time, the working bandwidth is remarkably improved, the whole Ka working
frequency band is covered, and the antenna has the advantages of being small in
insertion loss and simple and compact in structure.