Preliminary Experimental Research on Split-Cathode-Fed Relativistic Magnetron With Bidirectional Emission Structure

Simulations and experiments of an ${S}$ -band TEM-output relativistic magnetron (RM) driven by split cathode (SC) are proposed. In the previous researches on SC, as a result of the space-charge-screening effect of squeeze-state electrons accumulated nearby the emission surface, the diode current is limited, which finally results in low output power. To improve the output performance, a bidirectional emission SC (BSC) is introduced. Experimental results on EPA-90 high-voltage electron beam accelerator demonstrate that when the voltage is around 480 kV and the axial magnetic field is 0.49 T, comparing with a conventional unidirectional emission SC, the output power can be enhanced from 124 to 400 MW by adding an extra downstream emitter. This work lays a foundation for further researches to make the SC-fed RM more practical.