Rf Cavity Analysis And Design Of95GHz Gyrotron Oscillator

Gyrotrons are vacuum tubes for the generation of high-frequent microwaves. Theresearch on the gyrotron microwave tube was initiated by the demand of high power,high frequency electromagnetic wave source in the magnetically confined plasma fusionapplication. Since the initial phase of gyrotron development, new thrust areas have beenexplored. The gyrotron shows several unique advantages as a high power sourcecompare to the other millimeter/submillimeter wave sources either semiconductor baseddevices or vacuum based tube devices. At present gyrotron is used successfully in thefield of plasma heating, medical spectroscopy, material processing etc. Several newfields of technology like metal joining, planetary defense etc. are under exploration forthe futuristic use of gyrotron. Gyrotrons operating at95GHz are successfully beingused in: ECRH plasma generation for a electron cyclotron resonance ion source(ECRIS), and focused power transmission in the atmosphere. In this work, the design ofa95GHz gyrotron will be studied. This article will include:1. The theoretical analysis, using the linear theory slove the dispersion equation,computing start-up current research and analysis gyrotron operating parameters; Withapproximate nonlinear theory analysis beam-wave interaction efficiency efficiency andoptimize the length of interaction; Study solving process of domain analysis method ofopen cavity and study the basic characteristics of the high-frequency structure.2. Initialize actual model and simulation. choose the operating frequency at95GHz,TE5,3. calculated the cavity radius, electron beam guiding center radius, coldcavity analysis, based on Q and resonant frequency to optimize and initialize the finalcavity structure; combined the field distribution in cavity to calculate the start-upcurrent, Established the approximate range of operating parameters by analysis thedispersion curve; Take use of programming stand by large-signal theory analysis thestructure and operating parameters’ effect on beam-wave of interactionefficiency;Choosen one group parameters to do a deep analysis.3. Optimize the efficiency, Firstly, conduct a brief analysis of efficiency caused byeach part of the gyrotron secondly, studying the relationship between ohmic losses of cavity and interaction efficiency, and then proposed efficiency optimization programsand simple demonstration of different scenarios. Finally select the cavity with roundingsto optimize efficiency, Based on the optimized parameters to come out that the ohmiclosses density decreases and the output power and efficiency are improved.