Optimization and Improvement of Output Performance in G-Band Extended Interaction Klystron

To improve the output performance of G-band extended interaction klystron (EIK), several practicable methods have been discussed. Firstly, the synchronization characteristics of the electron beam with the operating mode are analyzed in order to obtain large output power for optimized period. The influence of input gap voltage on the beam-wave interaction is studied, and the well-matched condition is established by optimizing the structure of input cavity. The gap length of output cavity is optimized to improve the electric field distribution. By adopting the optimized gap length and non-uniform gap lengths, the output power significantly increases from 360 to 570 W and 660 W, respectively; the corresponding bandwidth reaches to 650 MHz and 470 MHz. Moreover, AJDISK calculation is adopted to compare the results with CST simulation, and the similar gains and tendencies validate the relative reliability of our designed beam-wave interaction circuit. Therefore, our proposed methods for improving the output performance of G-band EIK are feasible and utilizable.