以微波传输线理论和谐振腔等效电路理论为基础, 分别对速调管滤波器加载谐振腔输出回路的间隙阻抗实部和端口群时延公式进行了推导, 通过简化两公式的比值因子, 得到了利用端口群时延特性来分析输出腔间隙阻抗-频率特性的原理和方法。利用3维电磁计算软件CST分别对X波段和Ku波段两个滤波器加载输出回路进行模拟计算, 结果表明:群时延时间法与其他已有方法计算结果一致, 验证了此方法的正确性。基于模拟计算软件强大的后处理功能, 群时延时间法使速调管输出回路的计算步骤更加简捷直观。

The gap impedance and the group delay time of the output cavity for a klystron loaded with a filter are deduced using the microwave transmission line theory and the equivalent circuit theory. A method that analyzes the gap impedance of the output cavity through its group delay time is proposed. Two typical examples of the output cavity at X band and Ku band are calculated by the software CST, and the calculated results are consistent with those evaluated by other methods. The proposed method is proved to be reasonable, with more simple calculation and more explicit outcome based on the powerful post-processing capability of the calculation software.