缓变回旋管谐振腔研究

Study on gradually-varying cavity for a gyrotron

在高次模回旋管中,模式竞争是亟待解决的问题.本文基于广义传输线理论,得到能准确描述缓变结构谐振腔模式耦合的一阶传输线方程组;通过分析耦合系数,优化得到了一种新型光滑渐变(缓变)谐振腔.与直线连接的(折变)谐振腔相比,该腔体有更强的模式抑制能力,腔中非工作模式归一化幅值可达-100 dB,输出行波段非工作模式归一化幅值可达-88.6 dB.

The mode competition is the problem to be solved urgently m mgh-order moae gyrotron, tlasea on me generallzea meory o： transmission line, a group of first order transmission line equations that can accurately describe the coupling modes in a gradually- varying cavity is studied. Through analysing the expressions of the coupling coefficients between the various modes, a gradual-varying cavity for a gyrotron is designed. It is proved that the power in spurious modes in this novel cavity may be kept far below that in the line-joint cavity. The normalized amplitudes of non-operating modes can reach -100 dB in cavity and -88.6 dB in travelling wave guide.