Abstract
A key limitation of magnetically insulated transmission line oscillators (MILOs) is their relatively low efficiency, typically less than 20%. To address this issue, we propose an X-band planar MILO operating under a modest external magnetic field. Particle-in-cell simulations demonstrate that at a diode voltage of 727 kV, a diode current of 7.2 kA, and an applied magnetic field of 0.25 T, the device achieves an output microwave power of 2.2 GW at a frequency of 8.96 GHz. This corresponds to a beam-wave conversion efficiency of 42%. The required external magnetic field can be supplied by a permanent magnet weighing only 29 kg. Compared to existing high-power microwave sources, the proposed device exhibits notable advantages in terms of efficiency, output power, and compactness, thus providing a very promising foundation for future practical applications.