S波段长脉冲相对论速调管放大器的实验研究

Investigation on S-band long pulse relativistic klystron amplifier

介绍了S波段强流长脉冲相对论速调管放大器(RKA)的高频系统设计、长脉冲强流相对论电子束(IREB)的调制及微波提取等方面的实验研究结果。重点阐述了长脉冲IREB调制和输出微波中的自激振荡问题。通过采用高阶工作模式以及参差模式设置的谐振腔、提高系统安装的同心度和调节电子束参数等措施,使自激振荡得到了抑制。采用550 kV,4 kA及210 ns的环行电子束,经过优化调节RKA参数,使强流调制电子束流脉宽由50 ns增加到150 ns,同时得到了3.2 kA的基波调制电流。从该RKA得到了峰值功率580MW、脉宽140 ns的输出微波,束波转换效率26%,增益34 dB。

This paper presents the progress on design and adjustment of cavities, experiments of beam-current modulation and microwave extraction for an S-hand long-pulse-intense-current relativistic klystron amplifier. Modulation of long-pulse intense relativistic electron beams and self-exciting oscillation of output microwave are described in detail. The cause of self-exciting oscillation and its results is also introduced. The self-exciting oscillation was suppressed to a certain extent by taking relevant adjustments. In experiments, a hollow electron beam of 550 kV, 4 kA and 210 ns generates an electron beam with modulated current of 3.2 kA and pulse width of 150 ns after optimization and adjustment of the parameters of cavities. More than 580 MW RF power with a duration of 140 ns is obtained. The efficiency is about 26%, and the gain is about 34 dB.