Theoretical and experimental phase distortion studies on traveling wave tubes

Traveling wave tubes for satelite communication are required to operate with high efficiency, yet with low phase distortion in order to obtain a large channel capacity in the satellite repeater. A general efficiency and phase distortion analysis for traveling wave tubes was therefore carried out, using a large signal computer program. The phase shift, the AM/PM conversion factor and the efficiency with and without collector depression at saturation and at reduced drive levels have been evaluated for a large range of tube parameters.