Linear theory of tunneladder traveling wave tubes

Through placing a thin hollow electron beam in the electronic tunnel of the tunneladder TNT, this article derived the linear theory of the tunneladder traveling wave tubes(TWT). A dispersion equation of the tunneladder TWT was derived, and the small signal gain and the working phase velocity were computed. The results manifest that the gain of the Tunneladder TWT is high, and the bandwidth is narrow. When the width of the channel varies from zero to the double of the ring radius, the linear gain decreases within 1%. When the ring radius augment 10%, the linear gain decreases 57%, and the ridge height augment 10%, the linear gain increases 62%. Thus, the width of the channel plays a small role on small signal gain, but the height of the ridge and the radius of the ring affect small signal g