摘要
采用小信号理论,在考虑到透射、反射束电子不同作用下,分析了虚阴极振荡器产生微波的机制,获得了计算微波主频的方法,讨论了增强束波作用效率的方法,并提出一种新型结构的虚阴极振荡器。该振荡器的阳极后放置了一个谐振腔,谐振腔长度很小,虚阴极不能在其中形成,谐振腔受到反射电子束激励并建立强场,场对入射电子进行调制,同时采用同轴结构引出微波。利用2.5DPIC程序对新型的结构进行了数值模拟,验证了理论分析的正确性。在入射电子束电子能量为520keV和电子束流12.5kA的条件下,获得微波平均功率为1GW,频率为3.66GHz,平均束波转换效率为15.3%。
A simple model was developed to investigate the generation mechanism of virtual cathode oscillation microwave based on space-charge effect under small signal condition. With this model, the generated microwave frequency in a vircator can be calculated. On the basis of theoretical analysis, an improved virtual cathode oscillator was brought forward. In this configure, a resonant cavity is located behind anode, and the cavity is very small so that virtual cathode could not be formed in it. The reflected beam current may excited a cavity mode, which modulates injected beam; and microwave is extracted in coaxial structure. 2.5 D PIC numerical simulation was conducted to study it. Microwave pulse power of 1 GW at 3.66 GHz for 520 kV and 12.5 kA injecting e-beam was obtained, and power efficiency was about 15.3%.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2004年第2期209-214,共6页
High Power Laser and Particle Beams
基金
国家863计划项目资助课题。
