准两腔振荡器的理论和实验研究

根据两腔振荡器和返波管的特点提出了准两腔振荡器，其作用机理是两腔振荡器的机理，结构类似返波管.这种结构主要由调制腔组和换能腔组两部分组成，调制腔组实现电子束速度调制，调制后的电子束在通过一个微波场较弱的区间时实现电子束群聚，然后在换能腔组实现电子能量到微波能量的转化，并通过输出结构输出；同时，调制腔组和换能腔组之间存在微波耦合，换能腔组中的一部分微波能量可以耦合到调制腔组，形成一个正反馈回路，在一定条件下实现微波振荡.根据此理论，根据Sinus-700加速器的参数(800 kV，10 kA)设计了一个X波段的高功率微波器件，2.5维Particle in Cell (PIC)程序模拟的效率为28%，微波频率为9.42GHz，微波输出功率为2.25GW，实验上得到的微波输出为微波频率9.40GHz，微波输出功率2.44GW. 关键词： 两腔振荡器 返波管 多波切仑可夫微波器件

Experimental and theoretical study of a quasi-bitron as a new high-power microwave device

A new type of high power microwave device is developed as a quasi-bitron. The device is simple and composes of two parts, the modulation cavity and the extraction cavity, with a coupling between the cavities. The structure has two working modes, one of them is the working mode, and competition between modes can be easily avoided even when the RF field in the device is very strong compared with the BWO (backward wave oscillator). Besides the theoretical analysis, the model has been realized on 2.5 PIC (particle in cell) simulation code. A 9.42GHz bitron oscillator is designed and its theoretical efficiency is 29.4%. The simulation shows the device achieves the efficiency 28% when the beam is 800 kV and 10 kA, and outputs RF power of 2.25GW. The experiment was also carried out on Sinus-700 accelerator. The measured microwave power is 2.44GW at the frequency 9.4GHz.