3-D Fast Nonlinear Simulation for Beam–Wave Interaction of Sheet Beam Traveling-Wave Tube.

In this paper, a 3-D fast time-domain nonlinear algorithm (FTDNA-3-D) based on particle-in-cell method for the beam–wave interaction of the sheet beam slow wave structure (SWS) is presented. Calculation equations of the circuit electric field and the space charge electric field are given. Calculation approaches of the energy exchange and the particle mover are displayed. A simplified coupling impedance simulation approach for sheet beam SWS is indicated. The FTDNA-3-D takes the transverse electric field and the focusing magnetic field into consideration. The FTDNA-3-D could reach a high simulation speed. This novel algorithm gives a faster accurate choice for the design of sheet beam traveling-wave tube (TWT). It could be used to enhance the design efficiency of sheet beam TWT. A Ka-band staggered double vane TWT is used to verify the FTDNA-3-D. Simulation results of output power and gain versus frequency from FTDNA-3-D are compared with results from CST particle studio. The results of FTDNA-3-D are in accord with CST particle studio well. [ABSTRACT FROM AUTHOR]