Simulation of L3-Harris L-4953 Crossed-Field Amplifier

Currently, there is a lack of publicly available design specifications for Crossed-Field Amplifiers (CFAs), which severely impedes CFA research in the public domain. The L3-Harris CFA, L-4953, was commonly used for the Air Route Surveillance Radar (ARSR-1/2) since the 1970's. This is a high power $\left( {P_{out}^{peak} \approx 5\;{\text{MW}},P_{out}^{avg} \approx 3.2\;{\text{kW}}} \right)$ , moderate gain (G=11.2 dB), pulsed ( t pulse = 1.8 μs), L-band (f = 1.28 to 1.35 GHz), reentrant, backward wave, thermionic cathode amplifier. Our group has been developing a particle-in-cell (PIC) model of the CFA to study power saturation and the effects of electron injection. Here, VSim is used to validate the model against CFA operation specifications, such as gain, bandwidth, and dispersion. Preliminary, non-optimized simulation results show as table 9 dB gain at in only 10 ns with a relatively coarse grid of 101×101×60 cells. The short time required to reach steady state and the low number of grid cells allows for short simulation times on the order of only a few hours for common multi-core processors. This makes this CFA design an ideal standard for simulation studies. Additional simulation studies are planned using ICEPIC. We will report the results of the simulations, comparison between the two different PIC codes, assessment with operating specifications, and studies of the electron injection models.