Physical analysis and numerical simulations of ultra wideband plasma relativistic microwave noise amplifier

The physical mechanism and output properties of the plasma relativistic microwave noise amplifier (PRNA) are studied numerically by using all electromagnetic particle-in-cell (PIC) code. Firstly, dispersion relation between operating mode slow space charge wave electron beam without coupling is simulated analyzed. Simulation results show that both density <i>n</i><sub>p</sub> radial thickness Δ<i>r</i><sub>p</sub> affect characteristics markedly their increasing can lead frequency at beam-wave resonant point to be enhanced. voltage current also frequency, but effect relatively slight. Secondly, variation linear growth rate bandwidth then evaluated theory. Calculations PRNA has virtue wideband output. Its reach a GHz level. By adjusting parameters Δ<i>r</i><sub>p</sub>, current, tuned over wide range. Therefore fine tunability. Based on above calculation results, whole PIC simulations carried out verify virtues basic features field distributions in evolution process given. bunching energy release plotted. Simulations with 1.4×10<sup>19</sup> /m<sup>3</sup>, 500 kV 2 kA applied magnetic 2.0 T, 200 MW efficiency about 20% obtained. ranges from 7.0 9.0 GHz, band width reaches GHz. And TEM coaxial waveguide. Both relations increases clearly increasing. influence small gap distance little frequency. research will provide useful reference for further designing PRNA.