Power and Efficiency Enhancement of Reltron With Two-Stage RF Output

A novel configuration of a reltron was proposed to enhance its RF output power and efficiency by modifying the conventional design. In the proposed design, an additional power extractor waveguide cavity was put between the output waveguide and the beam dump to recover the remainder energy of the bunched electron beam transporting to the beam dump of the device. The RF electric field profile confirmed π/2 mode resonance, ensuring intense electron bunching through the modulation cavity and a stable device oscillation. The 3-D particle-in-cell (PIC) simulation of the device predicted the RF output power of ~240 MW with ~38% efficiency extracted from the conventional output port and ~65 MW with ~10% efficiency from the additional extractor port. The combiner port provided an RF output power of ~295 MW with ~46% efficiency.