A staggered double-vane slow-wave structure with double sheet electron beams for 340 GHz traveling wave tube

An improved slow-wave structure (SWS) for a 340 GHz traveling wave tube (TWT) is proposed. The dispersion curve and transmission characteristics of SWS have been calculated and analyzed. The transmission and reflection of the RF structure are S-21 > -7 dB and S-11 < -16 dB, respectively. Two sheet electron beams with identical physical parameters are used to control the operation of a TWT. In addition, the output power, gain, and bandwidth of the TWT were studied using three-dimensional particle-in-cell (PIC) simulation method. A uniform constant magnetic field with the magnetic field density of 0.2 T is used to focus the sheet electron beam. The results of the PIC simulations show that the TWT achieves the maximum output power of 12 W and the 3 dB bandwidth of 25 GHz (328-353 GHz) at the input power of 10 mW. At 340 GHz, the output power of 12 W and the gain of 30.8 dB are obtained.