Rotary joint for switchably rotating between a jointed and non-jointed state to provide for polarization rotation

A method of operating a rotary joint for joining two waveguides for guiding electromagnetic waves, the rotary joint comprising a first portion adapted to receive a first waveguide, a second portion adapted to receive a second waveguide, and a third portion adapted for polarization rotation and arranged between the first portion and the second portion, the rotary joint being configured such that two portions selected from the group comprising the first portion, the second portion and the third portion are rotatable between at least two different angular positions around a central axis, the method comprising:

• switching between a jointed state, in which the first portion, the second portion, and the third portion contact each other for electrical connection, and a non-jointed state, in which the first portion, the second portion, and the third portion have no contact or less contact with each other as compared to the jointed state;
• and
• rotating each of the two rotatable portions between the at least two different angular positions,
• wherein the rotary joint is adapted to switch between the jointed state and the non-jointed state by rotating the two rotatable portions such that the two rotatable portions are lifted away from each other in a direction of the central axis.