Abstract: A waveguide-transmission line converter has a waveguide including side walls which have inner corners at an open end of the waveguide. The inner corners are beveled to provide tapered inner surfaces. Even if a dielectric substrate is assembled out of alignment with the waveguide due to an assembling error, edges of a ground metal layer on the dielectric substrate are exposed from the beveled inner corners at the open end of the waveguide. The beveled inner corners keep the waveguide spaced widely from edges of a matching element on the dielectric substrate, preventing an electric field concentration from occurring between the waveguide and the matching element. The waveguide-transmission line converter has electromagnetic energy passing and reflecting characteristics prevented from varying.

Abstract: A waveguide-transmission line converter has a waveguide including side walls which have inner corners at an open end of the waveguide. The inner corners are beveled to provide tapered inner surfaces. Even if a dielectric substrate is assembled out of alignment with the waveguide due to an assembling error, edges of a ground metal layer on the dielectric substrate are exposed from the beveled inner corners at the open end of the waveguide. The beveled inner corners keep the waveguide spaced widely from edges of a matching element on the dielectric substrate, preventing an electric field concentration from occurring between the waveguide and the matching element. The waveguide-transmission line converter has electromagnetic energy passing and reflecting characteristics prevented from varying.