Terahertz Gyroklystron Amplifier Simulation Study

THz wave is one kind of electromagnetic wave whose frequency scope in 0.1-10THz(wavelength is in 30-3000μm).It is in the transition region of electronics to photon.Owing to the special position of THz electromagnetic spectrum,it has a lot of superior specific properties,and possesses very important academic value and application value.As a novel millimeter-wave coherent radiation source with high-power capability,high-efficiency and moderate bandwidth advantages, gyroklystron amplifiers have received a great deal of attention in recent years for a variety of applications such as high power millimeter radar,electromagnetic countermeasure(ECM),communications,precision guidance,material processing, plasma heating,and a new generation of particle accelerators and so on.At present the international study of gyroklystron has achieved great progress in high frequency wave band.This thesis combines the international development trend to discuss and study the gyroklystron carefully working in 220GHz,such as the high frequency system structure and the mutual action of electron beam and standing wave.Chief working as follows:1.Studies the input resonant cavity of gyroklystron works in 220GHz and the work model serve as TE₀₃,applying the method of traveling-wave field mating law,and spread out the model function of cavity,and uses the continuity of horizontal electric field and magnetic field,works out the sudden change resonant cavity field matching equation in the derivation,parses each model work value and reflection coefficient of the cavity at sudden change place by the solution of numerical equation.Then we can beg out the resonance frequency and quality factor,draw out distribution function of cavity infield.On the foundation of theory analysis,we work out the computational procedure of the high frequency and each reference amount of the resonant cavity by using the hardware of C++Builder6.0.This procedure is suitable for cool designing resonance frequency and quality factor calculation of cavity in the various sudden change structures.In this chapter,we find the solution and analyses by way of high frequency simulation software CST,get the result of sudden change structure resonant cavity,count out the physics reference amounts such as resonance frequency f and quality factor Q value of resonant cavity.By the way,we draw S parameter what reflect a whole cavity object to pay attention to a specific property directly.Then we make it compared with the last simulated results,and verifying correct nature of this procedure.2.Studying to the theory method of gyroklystron before detailedly introducing frankly,In the modulation cavity,the beam-wave interaction is studied with non-self-consistent nonlinear theory.However,this process is studied with self-consistent nonlinear theory in the output cavity.3.By using the nonlinearity theoretical to study the nonlinear interaction course of the gyroklystron works in 220GHz and the work model serve as TE₀₃,and make the corresponding nonlinear analysis.This process of beam-wave interaction is simulated. The developing software is C++Builder6.0 in the paper.After a big amount of numerical calculation,some parameters such as drifting length,dc magnetic field,operating voltage,operating current and the dimension of the cavity have been discussed,their influence over the efficiency are also discussed.Some valuable results are obtained. Some measure are put forward to improve the application interface,such as visualization,generalization and modularization.Counting two cavities and three cavities circles round all work parameters of klystron,and got corresponding efficiency, gain and bandwidth,and conquers the important foundation for later research.