提出采用圆形电子注和双排矩形梳状慢波结构作为w波段宽频带行波管注波互作用回路.对该慢波回路的“冷”态特性、输入输出结构等方面进行了模拟仿真和分析,研究结果表明,该结构色散特性较好,带宽较宽;通过调整双排矩形梳状慢波结构之间的距离和电子注通道半径的尺寸,圆形电子注系统取得了和带状注系统相同的耦合阻抗;且该结构传输特性较好,优化后整管的驻波比能在较宽的频带内保持在2以下.此外,对该慢波系统的大信号理论计算和PIC粒子模拟结果一致.在50mw驱动功率下,输出功率在10GHz带宽内大于40w,增益高于29dB
A double rectangular comb slow-wave structure with a round beam channel is proposed as the slow-wave structure (SWS) circuit of a broad bandwidth traveling-wave tube at W-band. The "cold" characteristic of the SWS and the transmission of the input/output structure are simulated and optimized in this paper. The results show that this circuit has a very broad bandwidth, and that the impedance of the structure with round beam channel can be the same as that of sheet beam by modifying the distance between the double vanes and the radius of the beam channel. Moreover, the transmission of the whole tube is so good that the VSWR can be kept at below 2 in a very broad bandwidth after optimization. The output performance is investigated by both the big signal theory MTSS and the PIC code MAFIA, and they have the same results that in 10 GHz bandwidth the output power is over 40 W and the gain is above 29 dB under a driven power of 50 mW.