Progress of the Methods for Optimum of Quasi-Optical Mode Converters at KIT

The paper reports the progress of the methods for the synthesis of Quasi-Optical (QO) mode converters at KIT in the period from 2018 until today. Typically, the QO mode converter consists a waveguide launcher and a mirror system. The first progress done is the development of the spectrum reconstruction method for smoothing the launcher wall. The second is the improvement of the method for the design of quasi-parabolic mirrors. The third progress considers the synthesis of a Denisov-type launcher for the conversion of co- and counter-rotating modes.