General design procedure for high-efficiency traveling-wave amplifiers

A general design procedure is developed for the design of both low-power and high-power high-efficiency traveling-wave amplifiers. The process is based on the selection of optimum values (for highest efficiency) of the design parameters C, QC, B and b from the large-signal curves and design of an amplifier with the particular type of RF structure specified by power and bandwidth requirements and operating parameters as near the optimum values as possible. In cases where the optimum design parameters cannot all be realized simultaneously, the design engineer will be able to select the parameter that he wishes to adjust. The procedure is first developed for helix-type tubes and then correction factors are derived that permit the design of amplifiers with any type of RF structure from the same set of curves.