An ultra wideband helical groove waveguide TWT

A coaxial helical groove waveguide with step-shaped groove profile, loaded by the annular electron beam guided by a strong magnetic field, has been proposed to produce ultra-wideband coherent radiation of higher frequency electromagnetic waves. The structure has been analyzed for hot dispersion and small signal gain. It is found that compared with other available coaxial helical groove structures, the present structure has dispersion free regimes for an ultra wideband frequency range; therefore the operation bandwidth can be remarkably extended.