Optimization design of bent circular waveguide TM01-TE11 mode converter

The bent TM01-TE11 mode converter is analyzed by theoretical calculation and numerical simulation, keeping the axes of the output port and that of the input in parallel. The mode converter is minimized by decreasing the inner radius of waveguide. The optimized results are shown as follows: the inner diameter of waveguide is 7.0 cm, the distance between the axes of the two ports of the mode converter is 8.03 cm, and the axial length is 15.11 cm. The overall power conversion efficiency exceeds 90% in the frequency range from 3.41 to 3.74 GHz and the efficiency reaches up to 95.6% at 3.60 GHz．