Reentrant double-staggered ladder coupled-cavity structure for X-band traveling-wave tube

The paper describes the design of an X-band coupled-cavity traveling-wave tube (CC-TWT) based on the reentrant double-staggered ladder coupled-cavity slow wave structure (SWS) using High Frequency Structure Simulator (HFSS) and particle-in-cell (PIC) code in Computer Simulation Technology (CST) Particle Studio. When the cathode voltage and cathode current are 25.9 kV and 5 A, respectively, the PIC simulation results show that the corresponding saturated output power is over 20kW from 8.6 to 9.7 GHz, the maximum output power can reach 28.8 kW at 9.2 GHz, and the electronic efficiency and the gain can reach over 15.6% and 40 dB.