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 H10mode into the circular H01and E01modes. If pure H01and E01modes 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 E01mode is performed by a conventional method, a new method had to be developed for the conversion of the rectangular H10mode into the circular H01mode.