Analysis on the mechanism of pulse-shortening in an X-band triaxial klystron amplifier due to the asymmetric mode competition

作者：Qi, Zumin^*; Zhang, Jun; Xie, Yongjie; Zhang, Yi; Wang, Zehua; Zhou, Xiaofeng; Zhu, Jianhui; Zi, Yanyong; Zhong, Huihuang

来源：Physics of Plasmas, 2016, 23(12): 123103.

DOI：10.1063/1.4969079

Asymmetric mode competitions are observed in the design of an X-band triaxial klystron amplifier with an asymmetric input cavity, and the generation mechanism of the asymmetric mode competition is analyzed in the paper. The results indicate that the asymmetric modes are excited in the buncher cavity. The asymmetric mode (coaxial TM612 mode) in the buncher cavity with the highest shunt impedance can start up first among the asymmetric modes with negative beam loading conductance. The coupling of the corresponding coaxial TE mode between the buncher and input cavity exacerbates the start oscillation of the asymmetric mode competition. The rationality of the analysis is demonstrated by cutting off the propagation of the corresponding coaxial TE modes between the buncher cavity and the input cavity, and the asymmetric mode competitions are thoroughly suppressed by specially designed reflectors and lossy material. In simulation, a microwave with a power of 1.28GW and a frequency of 9.375 GHz is generated, and the extraction efficiency and the gain are 34.5% and 41.5 dB, respectively. Published by AIP Publishing.

• 出版日期2016-12
• 单位中国人民解放军国防科学技术大学; 西北核技术研究所