A rotary joint for two microwave transmission channels of the same frequency band

This dual-channel rotary joint consists of two pairs of rectangular waveguide terminals, a circular waveguide which transmits both channels, and coupling elements between the rectangular waveguide terminals and the circular waveguide which convert the rectangular H
10
mode into the circular H
01
and E
01
modes. If pure H
01
and E
01
modes can be excited, perfect separation of the channels as well as-constant amplitudes and phases can be obtained when the Joint rotates. While the conversion into the circular E
01
mode is performed by a conventional method, a new method had to be developed for the conversion of the rectangular H
10
mode into the circular H
01
mode.