A novel self-injection relativistic backward wave oscillator

Abstract

A novel self-injection relativistic backward wave oscillator (RBWO) has been proposed. By introducing a self-injection path into the RBWO, a small portion of the energy in the reflector can be coupled to the upstream of the reflector, and then the formed electric field in the self-injection path region can pre-modulate the passing electron beam, to promote a frequency-locking oscillation of the electron beam. The pre-modulated electron beam can be expected to enhance the beam-wave interaction and suppress parasitic mode oscillation, which is beneficial for maintaining the dominant role of the operating mode. The proposed self-injection RBWO shows great potential for improving the conversion efficiency and pulse duration time. Through particle-in-cell simulation, a microwave with a power of 10.6 GW is obtained, when the beam voltage is 1.08 MeV, and the beam current is 18.6 kA. The conversion efficiency is 53%.