Cycle Of Slow Wave Structure Of Super-radiation Mechanism Of A Preliminary Study

Subnanosecond millimeter relativistic backward wave oscillator, based on superradiance mechanism, was a novelty microwave device developed in last few years. The dependence of peak power on the square of the density of electron beam is almost linear. With the theory analysis of the superradiance mechanism its condition that occurs from the.foundation. can be understood clearly.In the first chapter, the high power microwave device development process was reviewed, the physical mechanisms underlying superradiance phenomenon based on Cherenkov radiation expounded and the research activities in this field, both in and out of China, summarized.Employing the self-consistent nonlinear theory, the wave beam interaction and the wave developing with time in the subnanosecond millimeter relativistic backward wave oscillator were theoretically analysised. The basic condition that produced superradiance and the radiation power were gotten.Using the Particle-in-Cell (PIC) model, a 8 millimeter relativistic backward wave oscillator underlying superradiance mechanism was gotten, the influence on both operation frequency and radiation efficiency of the guiding magnetic field, the diode voltage, the beam current and the beam radius as well as the corrugation structure were also presented. The simulation results show the existence of both limits and optima for the studied parameters, related to the stable operation and the maximum efficiency, respectively. Underlying the conditions that The longitudinal guiding magnetic field is 1. 8T, diode voltage is 250 kV , the impedance is 150 Ω, we got a peak power as high as 100 MW for the TM01 mode at 38GHz.