Stability Analysis of Ka-band TE01-mode Gyrotron Traveling Wave Amplifier with Lossy Dielectric-Load Waveguide
损耗介质加载结构Ka波段TE01模回旋行波管放大器稳定性的分析

This paper, with the analysis of the propagation characteristics in a lossy cylindrical waveguide and using small-signal theoretical dispersion relation, presents study on the device stability with influence of the absolute instability and the backward wave oscillation in TE01-mode lossy dielectric-load gyrotron traveling wave amplifier. The numerical results show that lossy dielectric-load can heighten the start oscillation current of absolute instability, and increase depends on the magnetic field strength and the perpendicular-to-parallel velocity ratio of the electrons; The thickness of the lossy waveguide increases the start oscillation length of backward wave oscillation. The combined appropriate selection of the lossy waveguide thickness, permittivity, voltage, the applied magnetic field and the velocity ratio can effectively give attention to bandwith and instability to ensure the stable operation of the gyrotron traveling wave amplifier.