Three-dimensional analysis of multiple beam klystron

The three-dimensional analysis PIC code KARAT-3D was used to assess the multiple beam klystron(MBK). A power output of about 128 kW was obtained at 1.25 GHz when input voltage was 14 kV and input current was 20.8 A. Specially, the beam transimission coefficient and the current modulated coefficient were calculated.It was concluded that the current modulated coefficients were increased by the cavity number and that the energy of the electron decreased very fast when the electron passed the output cavity because some of the electron energy was transformed to microwave energy.