Design of an Electron Optics System for L-Band Klystron

This paper describe the design of an electron optics system for L-band klystron with a power of 20 MW. When the cathode voltage and the current are 223 kV and 172 A, respectively, the beam radius is 10 mm, and the transmission distance is more than 1000 mm. In the solenoid focusing system, two compensative coils are arranged outside the collector to increase the magnetic field near the output cavity. The electron beam transfers stably with a radius of maximum radius of 12 mm and a minimum radius of 9 mm.