Study of a $\text{TE}_{01}-\text{TE}_{11}$ Mode Converter for 340 GHz Gyro-TWTs

This paper presents the design of a 340 GHz $\text{TE}_{01}-\text{TE}_{11}$ mode converter for a terahertz-band gyro-TWT. Simulation results indicate that the mode converter achieves a mode conversion efficiency exceeding 95% in the 335.20-345.22 GHz range (relative bandwidth of 2.95%), while maintaining a port reflection coefficient below -30 dB across this bandwidth.