Studies on Efficient Operation of an X-Band Oversized Slow-Wave HPM Generator in Low Magnetic Field

The efficient operation of high-power microwave (HPM) sources using slow-wave structures (SWSs) in low magnetic field has been an attractive aim pursued by HPM researchers. This paper presents the latest experimental results of an X-band oversized SWS HPM source operating at low guiding magnetic field with both power and efficiency enhancements. Driven by an electron accelerator with diode voltages of 450-900 kV, the generator operated with the output microwave power ranging from 0.5 to 3 GW and the efficiency being kept at about 25%. The optimized magnetic field was in the 0.5-0.75 T range, depending on diode voltages. Without the employment of superconductive-solenoid system, a very stable 100-Hz repetitive operation with 1.5-GW output microwave power was realized in the 1-s-burst mode.