Coaxial-waveguide rotary coupling assemblage

Abstract

A coaxial-waveguide assemblage is disclosed herein of the invention includes a first coaxial transmission line having a first inner and a first outer conductor. The inventive assemblage further includes a waveguide electromagnetically coupled to the first coaxial transmission line, where an inner surface of the waveguide bounds a signal propagation space. The waveguide is also electromagnetically coupled to a second coaxial transmission having a second inner and a second outer conductor. The inner conductor of the second coaxial transmission line is disposed to rotate about a first vertical axis, thereby enabling the second coaxial transmission line to be connected to a rotating antenna. In a particular implementation the coaxial-waveguide assemblage is disposed within a rotary joint operative to couple electromagnetic energy between first and second signal ports. An axially elongated dielectric sleeve, disposed about the second inner conductor, will preferably be dimensioned to extend into the waveguide propagation space. The rotary joint will generally include a bearing arrangement interposed between the second outer conductor and the axially elongated dielectric sleeve of the second coaxial transmission line. Tuning of the coaxial-waveguide assemblage is facilitated by a tuning cavity in communication with the propagation space.