Inner Slotted Threaded Waveguide And Dual Electron Beam Coaxial Cavity Cyclotron Pipeline Theoretical Research

Gyrotron is a new and important type of electrical microwave device from 50th years of last century to current. As a high power resource, it can produce and amplify milimeter and submilimeter-wave radiation at high frequency. So its naissance brings a lot of hope and promotion to application and deploitation of milimeter and submilimeter-wave.Because of gyrotron,s superiority of high peak power and average power among many known milimeter and submilimeter-wave gyrodevices, it has been paid much respect in the world for application in many areas such as plasma heating, RF accelerator, millimeter radar, DEW and so on. During the last thirty years gyrotron has been subjected to extensive theoretical and experimental studies. This thesis analyse the linear theory of Gyro-TWT with spiral corrugated waveguide and two-beam coaxial gyrotron. First of all, base on the theory of coupled-wave, the dispersion equation and coupling condition of spiral corrugated waveguide is realized by applying the method of impedance perturbation. Then the nonlinear coupled electromagnetic and electron motion equations were obtained from the Lorentz equation. And numerical calculation and analysis of cold cavity by pic software were applied to analyze the both hot and cold dispersion characteristic of this waveguide.The second, as a novel gyrodevice the two-beam coaxial gyrotron which was proposed by professor Liu shenggang is analysed by kinetic theory of ECRM. General dispersion equation for ECRM and expressions for the interaction power and the starting current are derived in the case of eccentricity of the electron beam in the coaxial cavity. Finally, by numerical calculation, the advantage of two-beam coaxial gyrotron in interaction efficiency and mode competition are discussed.