Design of a novel circular waveguide TM02-TE11 mode converter

Abstract

In this paper, we report the design methods and numerical results for a novel and compact circular waveguide TM02-TE11 mode converter, which has a high pure TE11 mode output. The converter has been designed to transform the high order TM02 circular waveguide output mode from relativistic backward-wave oscillators into the fundamental TE11 circular waveguide mode. The results show that the purity of output fundamental TE11 mode of the converter exceeds 99.6% for an operating frequency of 9.4 GHz and the power capability is as high as 1.66 GW. The mode conversion efficiency is more than 90% from 9.23 to 9.83 GHz band and the relative bandwidth is approximate 6.38%.