Time-Domain Modeling of TWT Collector Using EBAC

In this paper, TWT spent beam behavior is investigated using the electron beam analyzing code (EBAC). Spent beam energy and temporal distribution are calculated by a Lagrangian TWT interaction code. Both steady-state and time-domain approaches are implemented to model the spreading behavior of spent beam with different current densities. As a result, it is shown that for a medium power TWT, the results of the steady-state model can be inaccurate near the saturation. Therefore, for collector design of such TWTs, it is more reasonable to use the time-domain model instead of the steady-state approximation.