Two-stage dielectric-loading for broadbanding a gyro-TWT

Abstract

A scheme of dielectric-loading for a gyro-traveling-wave tube (gyro-TWT) is proposed for a wider bandwidth at a higher gain. The method uses two-section dielectric-loaded Cylindrical waveguide as the interaction structure, with the first section overloaded to exhibit a valley between the two peaks in the gain-frequency response, while the other suitably loaded to exhibit a single peak centered at the valley so as to yield an overall wideband response. A bandwidth ∼8.8% at a relatively high small-signal gain ∼30 dB is predicted.