Determination of the Optimum Square Resistance of Absorbing Vanes of the Rotary Vane Attenuator

Dependence on the square resistance of the linear attenuation caused by an absorbing vane in a circular waveguide is investigated. The maximal attenuation is determined to be attained at the square resistance values in the range 130-150 $\mathrm{\Omega }$. Special constructions of impedance-matched low-reflectivity absorbing vanes are proposed and production-ready structural calculation are carried out.