This component, based on the theory of Periodically Coupled Waves (*), splits the 1 MW in the main transmission line into 12 rectangular waveguides; the TE01 circular mode in input is converted to the TE10 rectangular mode at the output.
The 12 output rectangular waveguides are symmetrically displaced around the circular input waveguide and coupled to it through selective holes.
To avoid the risk of arching, the converter is pressurised with SF6 (P = about 3 Bar abs)
The mechanical dimensions of the converter are experimentally optimized for a total power transfer.
Final Converter with terminal load
(*) S. E. Miller: Coupled wave theory and waveguide applications; The Bell System Technical Journal, May 1954, pag. 661, 719