Linear traveling wave tube amplifier utilizing input drive limiter for optimization

Abstract

A linearized traveling wave tube amplifier with average power limiter is disclosed. The device includes an average power limiter for the purpose of preventing a TWT from operating at output powers higher than the required operating point. The device includes a detector for dynamically producing a detector signal proportional to an average power of an input signal and substantially independent from a peak power of the input signal, and an attenuator, in communication with the detector and the amplifier, for dynamically attenuating the input signal according to the detector signal. The limiter allows the TWTs to be optimized for performance at the required operating point, resulting in higher efficiency, and eliminates the need to size the amplifier for a power level any larger than the required operating point which reduces the cost and complexity of the system. The limiter protects the TWT while not degrading the linear performance of the TWT by limiting the average power while allowing peak powers of short duration to pass with low loss.