Preliminary experimental study on a GW-level C-band relativistic magnetron

A C-band relativistic magnetron with an improved structure is investigated experimentally in this paper, which was proposed in the previous work. This magnetron adopts a periodically symmetric extraction structure, achieving strong coupling with non-\pi modes. It enables the single operation of the \pi mode, enhancing the stability and efficiency of the magnetron's operation. In the simulations, the microwaves are generated with a peak power of 2.53 GW and a power efficiency of 58.3%. In the initial experiments, the deposition of axial leakage current on the output inner conductor severely affected the operation of the CRMIS. By improving the structure of the output inner conductor, the effect of axial leakage current was mitigated. At a voltage of 537 kV and a magnetic field of 0.275 T, a diode current of 9.1 kA was obtained, and the microwave power reached 1.27 GW at a frequency of 4.367 GHz, corresponding to a power efficiency of 26%. However, when the diode voltage increased to 600 kV, a breakdown occurred between the anode vanes and the cathode cap.