Coax to rectangular waveguide coupler

A coax to waveguide coupler comprising:

• a rectangular waveguide having first and second broad walls spaced apart by first and second narrower walls, said waveguide being dimensioned for operation over a selected frequency range;
• a body of dielectric material disposed between said broad walls for loading said waveguide, said body positioned between the narrower walls of said waveguide, having a cross-sectional dimension substantially less than the width of said waveguide, and having first and second lateral walls generally parallel to said narrower walls of said waveguide;
• a coaxial transmission line terminated at said first broad wall of said waveguide, said first broad wall of said waveguide having an aperture at said termination, said termination being adjacent said first lateral wall of said body;
• a short circuit termination at one end of said rectangular waveguide;
• a probe coupled to the center conductor of said coaxial transmission line;
• said body having a slot along said first lateral wall adapted to receive said probe, and
• said probe extending through said aperture and being disposed in said slot.