WAVEGUIDE TWO-CHANNEL ROTARY JOINT

PROBLEM TO BE SOLVED: To provide a waveguide two-channel rotary joint in which the need of a vent waveguide is eliminated and rotation accuracy of an output port can be set easily, and which can be reduced in size.SOLUTION: A waveguide two-channel rotary joint comprises a first waveguide 22, and a coaxial tube 23. The first waveguide 22 includes a partitioned area 22A in a cylindrically extending hollow center. In the first waveguide 22, within one tube, a first propagation path 22a is disposed on one hand and a second propagation path 22b is disposed on the other hand. The coaxial tube 23 is connected to the first waveguide 22 in a right-angle direction and supported to be freely rotatable around the right-angle direction and, in the axial center, coaxially includes first and second transmission lines 23a and 23b which communicate to the first and second propagation paths 22a and 22b for mode conversion. In the partitioned area 22A, a short-circuit plate 22c, the first transmission line 23a and the second transmission line 23b are disposed. The short-circuiting plate 22c obliquely partitions the partitioned area 22A with a plurality of steps. The first transmission line 23a connects to the short-circuit plate 22c and communicates to the first propagation path 22a. The second transmission line 23b communicates to the second propagation path 22b.