Rotary joint is mainly used for the connection of fixed part and rotating part in radar feeder system. It can be divided into type I, type L and type U according to the structure form, and can be divided into single, double and multiple rotary joints according to the composition channel.

Ka and Ku band dual-channel rotary joint. The rotary joint includes Ka channel and Ku channel: Ka channel is composed of a door button waveguide coaxial converter and a probe type waveguide coaxial converter, Ku channel is composed of two door buttons The coaxial outer conductor of the Ka channel acts as the coaxial inner conductor of the Ku channel to realize the nested integration of the Ka channel and the Ku channel, and the Ka channel coaxial choke groove is bonded with absorbing material The ring ensures the isolation between Ka channel and Ku channel. Compared with the traditional nested design, the present invention has simple structure and convenient debugging, and is especially suitable for high-frequency multi-channel mechanical rotation radar system.