Particle-In-Cell Simulation Analysis of a Multicavity W-Band Sheet Beam Klystron
Particle-In-Cell Simulation Analysis of a Multicavity W-Band Sheet Beam Klystron
复制标题
DOI：
10.1109/ted.2010.2082544
复制
发表时间：
2011
影响因子：
3.1
通讯作者：
Y. Shin;Jian-xun Wang;L. Barnett;N. Luhmann
中科院分区：
文献类型：
--
作者：
Y. Shin;Jian-xun Wang;L. Barnett;N. Luhmann
研制了一种w波段片束速调管，作为一种便携式相干辐射源，应用于主动拒阻系统。交互电路设计采用8个交错调谐腔（多间隙结构）和12:1宽高比的片状电子束（74 kV和3.6 a），产生50 kW的峰值功率（平均2.5 kW）和40 db增益，瞬时带宽为200 mhz。输出腔被设计成具有利用光波叠加的准光学（QO）外部耦合器。利用一维磁盘模型代码和三维粒子单元（PIC）求解器对电路设计进行了优化。迭代仿真分析表明，五间隙结构可以提供足够的输出功率和稳定的单频工作，无模竞争，是qo输出腔的最佳结构。三维PIC仿真结果表明，设计的电路在94.5 GHz频率下，以4w的输入驱动信号产生稳定的50kw输出功率，增益为40db。频率扫描预测在2π模式下的3db带宽为150 MHz。数值模拟结果与小信号分析结果吻合较好，从而为QO速调管放大器模块的输出性能预测提供了信心。
A W-band sheet beam klystron is being developed as a portable coherent radiation source for active denial system application. The interaction circuit design employs eight stagger-tuned cavities (multigap structure) and a 12:1-aspect-ratio sheet electron beam (74 kV and 3.6 A) to produce 50-kW peak power (2.5 kW average) and 40-dB gain with 200-MHz instantaneous bandwidth. The output cavity is designed to have a quasi-optical (QO) external coupler utilizing optical wave superposition. The circuit design has been optimized by using a 1-D disk-model code and a 3-D particle-in-cell (PIC) solver. The iterative simulation analysis predicts that a five-gap configuration is the optimum structure for a QO-output cavity because it provides sufficient output power and stable single frequency operation without mode competition. The 3-D PIC simulation predicts that the designed circuit produces stable 50-kW output power from a 4-W input driving signal, with 40-dB gain, at 94.5 GHz. The frequency sweep predicts a 3-dB bandwidth of 150 MHz in 2π-mode operation. The numerical simulation results agree well with the small-signal analysis, thereby providing confidence in the predicted output performance of the QO klystron amplifier module.