Abstract: The Vlasov-Poisson equations are used to simulate the propagation processes of relativistic electron beam (REB) in one plate or two plates.The position of cumulative maximum space charge,the oscillating frequency,of current J,elrctron number density n and electric field E in different positions versus injecting electron number density n₀ and injecting electron velocity v₀ in one plate model,and the inject-ing current J₀ and the distance between the two plates in two plates model are investigated.Numerical results of virtual cathode position are closed to the results given by stable theory.Its oscillating frequency is in agreement with the empiric expresion (1~√2π)ω_peb.Numerical simulation result for injecting elec-tron beam density having Guass distribution for volecity,spread of energy ΔE_n/E_n < 10% appears to be in largely conformity with the conclusion of monoenergy case in one plate model.

Key words: relativistic electron beam, vircator, oscillation