Low VSWR Waveguide Twists

Waveguide, the term usually covers various forms of hollow metal waveguides and surface wave waveguides. Among them, the former is called a closed waveguide because the electromagnetic wave it transmits is completely confined inside the metal tube. The latter is also called open waveguide because the electromagnetic wave it guides is confined to the perimeter of the waveguide structure. Such waveguides play a vital role in microwave ovens, radars, communications satellites, and microwave radio link equipment, where they are responsible for connecting microwave transmitters and receivers to their antennas. Waveguide twist is also called waveguide torsion joint. It changes the direction of polarization by reversing the direction of the wide and narrow sides at both ends, so that the electromagnetic wave passes through it, the direction of polarization changes, but the direction of propagation remains unchanged.
When connecting waveguides, if the wide and narrow sides of the two waveguides are opposite, it is necessary to insert this twisted waveguide as a transition. The length of the waveguide twist should be an integer multiple of λ g/2, and the shortest length should not be less than 2 λ g (where λ g is the wavelength of the waveguide).