Multimode Steady-State Analysis for a Gyrotron Traveling Wave Amplifier Based on a Distributed Loss-Loaded Metal Cylindrical Waveguide

In this paper, a multimode steady-state theory is established to analyze the beam-wave interaction of gyro-traveling wave tube (Gyro-TWT) based on a distributed loss-loaded waveguide. The analysis for improving stability with uniform dielectric-loaded and periodic dielectric-loaded waveguides was studied. Using the proposed theory, the realization process of the steady amplification for a Ka-band fundamental mode Gyro-TWT was discussed. The theoretical results for the RF output power are in good agreement with those in the experiments at a 7% velocity spread.