Linear Characteristic Of Cylindrical Waveguide TM-Mode Cyclotron Autoresonance Maser (CARM)

High-power radiation sources in millimeter and sub-millimeter waves have a great prospect of applications to radar, plasma heating, high-gradient linear colliders, and communications, and therefore, attract more and more attention in many countries. Microwave devices play an important role in high-power microwave technology. And as one of microwave devices, Bragg reflector is focused by researchers in the world.Previously, a great deal of attention had been paid to the transverse-electric (TE) mode gyro-devices such as gyrotron, gyro-peniotron, cyclotron autoresonance maser (CARM), but very little to the transverse-magnetic(TM) mode operation. Compared to the TE-mode, the TM mode has not only transverse electric field, but also has axial electric field, which may substantially affect the motion of the electrons in the axial direction when in interacts with a relativistic electron beam in a gyro-device. In the CARM mechanism the axial kinetic energy of the electrons is pumped into the transverse kinetic energy and then is delivered to the electromagnetic wave by beam-wave interaction which enlarges the electromagnetic wave. Therefore, use of the TM mode to CARM operation is not only favorable but may have advantages.This thesis pays attention to the dispersion characteristics, growth rate of the TM-mode CARM and analyzes the influence of the parameters on the output power and the gain. Attempt is made to a new method to enhance the output power and improve the capability of this kind of amplifier through the continuous optimization of parameters. The results show that cylindrical waveguide CARM amplifier operating in TM mode has high output power and gain and achieves our desired objectives.The first chapter introduces the high power microwave application, development, the meaning and main work of this thesis.The second chapter expatiate the theory of electron cyclotron maser, the operational principle of CARM, and on the basis of it to dissertate the operational principle and the practicable of cylindrical-waveguide CARM amplifier.The third chapter analyzed the interplay of the electrons and wave using the gyro-kinetics theory of electron cyclotron maser. The dispersion equations have been educed by using two methods based on the gyro-kinetics theory of electron cyclotron maser and the linear theory of Maxwell-Vlasov equations and Laplace transform, and a simulation code has been made by FORTRAN to compute dispersion equations of cylindrical-waveguide CARM amplifier.The simulation code's reliability has been attested by simulating the experiments of cylindrical-waveguide CARM in the forth chapter.In the fifth chapter, it analyzes the affection of the output power and the gain under the different parameters.In the sixth chapter, the TM_1,1, 35 GHz cylindrical-waveguide CARM amplifier has been simulated and the parameters has been optimized, and the beam-wave interaction length is 40cm, and the highest gain is 87.94dB. The thesis contributes to the theoretical and experimental studies of cylindrical-waveguide CARM amplifier from the theory and computer simulation. At last, the summarization and some expectations of this work are made out.Main works in the dissertation are as follows. The thesis produced and demonstrated that the CARM amplifier can employ the TM mode. Using the linear theory based on Maxwell-Vlasov equations and Laplace transform to derive the dispersion equation of the cylindrical-waveguide CARM amplifier.