Numerical simulations of microwave energy extraction from a high-gain, high-power pulse compressor with a plasma switch

Resonant microwave pulse compressors producing output pulses of megawatt-to-gigawatt peak power with high (tens and hundreds) power gain operate at high pressures of a background gas filling a compressor´s cavity and switch¹. Meanwhile, at present, there is no clear understanding of processes governing the plasma formation and ultimately determining the output power in such compressors. In this work, numerical simulations of the microwave energy release from a compressor comprising a gas-filled cavity and interference switch were carried out. The plasma discharge in a switch in a waveguide H-plane tee was modeled using the code MAGIC². Gas ionization, plasma evolution and interaction with RF fields accumulated within the compressor were simulated using different approaches provided by MAGIC: particle-in-cell approach accounting for electron-neutral collisions, gas conductivity model based on the concept of mobility, and hybrid modeling. The dependences of the microwave output pulse peak power and waveform on parameters that can be controlled in experiments, such as the external ionization rate, RF field amplitude, and background gas pressure, were investigated. Results of these simulations will be presented.