带状注速调管单端口输入腔的场形平衡方法

Balancing Field Distribution in Single-Port Input Cavity of Sheet Beam Klystron

对X波段带状注速调管单端口输入腔中间隙纵向电场(电子注方向)的场形平衡问题进行了研究。通过在另一侧腔体外加载封闭波导,使其内部的电场场形可以在一定范围内进行调整。这种方法简化了驱动装置,并能避免双端口激励方法中输入信号相位不一致引起场形失衡的问题。使用CST软件进行模拟计算获得了较好的优化结果,随后为验证该方法的有效性,使用加工的冷测模型对单端口耦合的输入腔进行了测试,实验结果表明:加载平衡波导可以有效的改善场分布,此外,通过改变调谐钉深度和加载波导侧的耦合孔尺寸对场分布也有明显的调节作用。

A novel method was developed to balance the distribution of the longitudinal electric field（in the beam propagating direction） in the single-port input cavity′s gap of the X-band sheet beam klystron.The original work is that a loaded waveguide is installed at the opposite side of the input cavity,so that the field can be adjusted within a certain range to achieve a uniform distribution.The newly-developed technique simplifies the driving unit,and solves the problem of the input signal asynchronism of the double-port input.The structure was optimized by means of a simulation with software package CST-Microwave Studio.The feasibility was verified with the lab-built cold test setup.The tested results show that the loaded waveguide is capable of easily adjusting the field distribution.In addition,the depth of the tuning nail and the dimension of the coupling aperture were found to strongly affect the field distribution.The experimental data agree fairly well with the simulated results.