Compact Oversized TE01-to-TE11 Mode Converter based on Deformed Waveguide

A Q-band oversized TE 01 -to-TE 11 mode converter is designed for high power transmission line of gyro-TWTs. To obtain a compact and broadband structure, the deformed circular waveguide, named quad-polar waveguide, which can improve the conversion capacity of between TE 01 mode and TE 11 mode is introduced. The axis perturbation is synthesized by iteration method. Validated by simulation software, the designed mode converter has the efficiency over 95% in the range of 46.9 GHz to 49 GHz.