PIC Simulation of a Periodically Dielectric Loaded Millimeter Wave Gyro-twystron Amplifier

A periodically dielectric loaded W -band gyro-twystron has been designed and studied for its beam-wave interaction behavior using a commercially available Particle-In-Cell (PIC) code “CST Particle Studio”. The present gyro-twystron is operated in circular TE
₀₁
mode and driven by the DC voltage of 57kV and 5A of electron beam current. The dielectric loading in the output section suppresses the spurious backward wave modes, including TE
₁₁
, TE
₂₁
, and second harmonic TE
₀₂
modes. The PIC simulation of the present dielectric loaded gyro-twystron produced a peak RF output power of ~84 kW at 94 GHz in TE
₀₁
mode. The power conversion efficiency and the saturated gain are calculated as ~29 % and ~32 dB, respectively.