新型反射腔在多频相对论返波振荡器中的粒子模拟研究

Particle Simulation of Novel Type of Reflector in Multi-Frequency Relativistic Backward Wave Oscillator

设计了两类新型同轴反射腔并成功地应用于多频高功率微波输出。反射腔采用非对称的同轴结构,置于同轴相对论返波振荡器(CRBWO)慢波系统的前端。文中利用2.5维CHIPIC粒子模拟软件进行粒子模拟研究。仿真结果表明,带有两类新型同轴反射腔的双频CRBWO都实现了X波段双频稳定输出,并且其工作的电压和磁场的稳定性要明显好于传统谐振腔双频返波管。采用第二类新型同轴反射腔,在强流电子束电压480 kV,电流7.5 kA,磁场2.7 T的条件下,得到了稳定的三频、四频输出,其注波转换效率分别为15.3%和13.9%,明显高于其他类型的多频高功率微波器件。

The two novel types of resonant reflector with dissymmetric structures were developed as the high power multi-frequency output,and used in the design of the multi-frequency coaxial relativistic backward wave oscillator（CRBWO）,respectively.The newly-developed reflectors were calculated with 2.5-dimension particle-in-cell（PIC） simulation code CHIPIC.The simulated results show that the dual frequency CRBWO,equipped with the two types of resonant reflector,generated stable dual frequency output in the X-band,outperforming the conventional counterparts when it comes to the stability of the operating voltage and magnetic field.Moreover,with an electron beam of 480 keV,7.5 kA,and guided by a magnetic field of 2.7 T,the CRBWO equipped with the 2nd type of the newly-developed reflector produced stable multi-frequency（three-,and four-frequency） output with the standing wave conversion efficiencies of 15.3% and 13.9%,respectively,which are much higher than those of the conventional multi-frequency,high power microwave devices.