The Design of a Sheet Beam Electron Optical System for a K-Band Traveling Wave Tube

A sheet beam electron optics system (EOS) consisting of a sheet beam gun and a periodic cusp magnetic (PCM) focusing system is designed in this paper for a continuous wave K-band sheet electron beam (SEB) travelling wave tube (TWT). This electron gun is capable of generating a SEB with a current of 1.4 A at a voltage of 18 kV. The beam waist dimensions are 5.58 mm × 0.63 mm, indicating a large aspect ratio. To effectively focus the SEB, a periodically cusped magnetic (PCM) system is specifically designed. Simulation results indicate that the SEB, when confined by the PCM, can traverse the electron tunnel over a distance of 350 mm without any collisions.