High Mode Purity TE01 Input Coupler for Ka-band Gyro-TWT

A study of a high mode purity TE 01 input coupler for Ka-band gyrotron traveling wave tubes (gyro-Twt) has been presented. The input coupler has two T-type power-deviding sections. It can obtain high purity TE 01 cylindrical waveguide mode which is converted from TE 01 rectangular waveguide mode. On the basis of theoretical calculation, the main structural parameters were optimized by high frequency simulation software. Simulations predicts that the transmission of TE 01 mode was over −1.5dB from 32GHz to 37GHz and the transmission of other modes of competition was less than −30dB.