P2-11: Small-signal Eulerian hydrodynamic analysis of a plasma-filled helix TWT

Small-signal analysis of a plasma-filled helix traveling-wave tube was developed following Eulerian hydrodynamic approach. The electron beam was treated as a moving charged fluid and the plasma a stationary quasi-neutral fluid. The coupled circuit and electronic equation was developed and a Pierce-type hot dispersion relation obtained, which was then interpreted for the gain-frequency response of the device. The analysis was validated against an existing approach that treats the interaction as a boundary value problem by considering the beam-plasma system as a propagating medium of an equivalent relative permittivity tensor.