Compact reversed Cherenkov radiation oscillator with high efficiency

An all-metal metamaterial slow-wave structure (MSWS), which comprises a hollow circular waveguide loaded by periodically arranged complementary electric split-ring resonators (CeSRRs), is proposed. Due to the CeSRRs with the characteristics of both subwavelength and strong resonance, the MSWS has both compact size and high interaction impedance relative to conventional SWS. Based on the reversed Cherenkov radiation in the MSWS, a compact reversed Cherenkov radiation oscillator (RCRO) with high efficiency is developed. The measured electronic efficiency is 19.54%, and measured output power is 10.16 kW at 2.221 GHz under the conditions that the beam voltage is 26 kV, the beam current is 2.0 A, and axial magnetic flux density is ∼962 G. The experimental results clearly show that the brand-new RCRO can be applied to large-scale scientific facilities, medical imaging, microwave heating, microwave disinfection and sterilization, and so on.