W波段带状注速调管电子光学及注波互作用系统

The electron optics system and beam-wave interaction for novel W-band sheet beam klystron

通过冷流模型理论对均匀场聚焦带状电子注的传输进行了研究,结果表明,通过增强聚焦磁场并提高电子注填充高度因子,可以有效降低Diocotron不稳定性并实现长距离的稳定传输.结合理论研究,对均匀场聚焦带状注电子光学系统进行了三维仿真设计与优化,利用自主开发的二维非线性注波互作用程序SBK2D,对W波段带状注速调管进行了初步分析,结果为输出峰值功率69 kW、效率24%、增益37dB、3dB带宽100 MHz.研制出的具有高机械对准精度的带状注速调管电子束管,带状注截面10 mm×0.5 mm,且在电子注电压20～82 kV,电流0.50～4.27A,长度100 mm的漂移通道内电子注传输直流通过率达到98%以上,高于之前在90 mm漂移通道内获得的95%的实验结果.

The cold fluid model theory was used for studying the transport and its instability for the sheet electron beam in the uniform magnetic field.The results show that if the focusing magnetic field and the filling factor of the beam in tube are increased,the Diocotron instability will be decreased to achieve a transportation in a long distance.Based on above results,3D simulation method was employed to design and optimize the electron optics system for the W-band sheet beam klystron.2D macro-particle model for sheet electron beam was proposed to develop a beam-wave interaction simulation program code for SBK,named SBK2D.The beam wave interaction processes in the W-band SBK with 8 multi-gap cavities are calculated using the SBK2D.The simulation indicated that a 69 kW peak power output at high frequency with efficiency of 24%,gain of 37 dB,and 3dB bandwidth of 100MHz at 3 dB can be derived.The W-band sheet beam tube was manufactured according to the design.The transmission rate and cross-section experiments were performed with the beam voltage in the range of 20~82 kV,beam current of 0.5~4.27A,and the length of tunnel of 100mm.More than 98% transmission rate with the beam cross-section about 10mm×0.5mm were obtained.