速调管输入腔开放腔的高频特性分析与实验研究

 建立了带输入波导结构的S波段速调管放大器输入腔开放腔模型，利用3维软件对其高频特性进行了数值计算研究，并对输入腔结构进行了优化设计。利用已加工的输入腔进行了高频参数的冷测实验研究，实验中的输入腔结构尺寸与高频分析中的完全相同，实验结果与高频分析结果一致。用3维PIC程序对电子束经过该输入腔后的束流调制以及注入微波的吸收情况进行了模拟。模拟结果表明：该输入腔与微波注入波导匹配很好，注入微波能被电子束和谐振腔全部吸收，在输入腔间隙后37 cm处得到了13%的基波电流调制深度。

High frequency characteristics analysis and experimental study on open input cavity for klystron

This paper presents high frequency characteristics analysis on an open input cavity of an S-band relativistic klystron amplifier and the optimization of the cavity geometry. Cold test on the high frequency parameters of the fabricated cavity is performed, and experimental results agree well with that of high frequency analysis. A three-dimension fully electromagnetic particle-in-cell(PIC) code is used to simulate the absorption of the injected microwave and the fundamental harmonic modulated current while the electron beams propagating the input cavity gap. The simulated results show that the cavity matches with the input waveguide and the whole energy of the driven microwave is absorbed by electron beams. The depth of the fundamental harmonic modulated current is about 13% at 37 cm downst