Abstract
A compact and high-efficiency {L} -band relativistic magnetron (RM) with all cavity axial extraction (ACAE) driven by a virtual cathode is proposed. Electron beam current produced by explosive emission cathode is controlled below space-charge-limited current to reduce electron energy dissipation before interaction region, and a low-energy state of electrons with the potential close to a physical cathode potential in an RM is formed by magnetic mirror and an external cathode. The particle-in-cell (PIC) simulation demonstrates that the proposed RM could output a pure TM 01 mode at the frequency of 1.63 GHz with gigawatt radiation power, and power conversion efficiency is improved from 47% to 65% when it is compared with an ACAE-RM with the same anode structure using transparent cathode.