Study On The High-Power Cherenkov Device Of Millimeter Wave

Relativistic Cherenkov devices are promising candidates as sources of high-power millimeter wave band radiation, which is an important direction of high-power microwave (HPM) technology and is focused by all the researchers in the world today. This dissertation gives theoretical, PIC simulative and experimental research on the high-power millimeter wave band Cherenkov device. Several valuable academic achievements are obtained.The "hot" dispersion equation in Cherenkov devices has been derived using the self-consistent linear theory. The design of the code is completed and the validity of our method is discussed. As examples, our general method is successfully applied to three typical slow-wave structures (SWS) , namely rippled-wall, disk-loaded and modified disk-loaded structures. In principle, the linear analysis can be applied to efficiently calculating all kinds of beam-wave interaction in various Cherenkov devices composed of axisymmetric SWSs with arbitrary periodic profile.A simple and unified theory developed by Gover is extended from FEL to the Cherenkov devices for the first time. In principle, the unified theory can be applied to compute the small signal gain and various gain parameters in various Cherenkov devices with arbitrary periodic profile and arbitrary electron beam shape by appropriate modification of the coupling coefficient. It has been successfully applied to analyze the interaction instabilities in sinusoidally rippled and modifieddisk-loaded waveguide.Particle simulation method is used to investigate the properties of the millimeter wave band device with large diameter, short period and two section SWSs, including the basic physical processes of the beam-wave interactions and the dependence of the microwave radiation on the structure parameters, the beam parameters, and the guiding magnetic field intensity. The simulation results confirm that the device with two section SWSs has several advantages, such as more effective beam-wave energy conversion, better spectrum quality, and higher input electrical power. A typical simulation result is that, at the beam parameters of 550kV, 5kA and beam radium...