Development of a 1.5-kW Average Output Power Coupled-Cavity TWT With a 10% Bandwidth Operating in ${X}$ -Band

A three-section coupled-cavity traveling-wave tube (CC-TWT) has been developed for avionic applications. The design parameters for a TWT operating in X-band with a high average power, high power, high efficiency, high duty, wideband, low weight, and rugged structure have been obtained. Data presented show a good agreement between simulation results and prototype test results. The smallsignal simulations were done with software developed in house for the evaluation of interaction impedance. The commercial code CST suite was used for the prediction of the dispersion diagram. The large-signal simulations were carried out with the “1-D code, computer program for analysis of CC-TWT,” by Cosmic. This paper explains the theory used for the design and shows the “cold test” and “hot test” results achieved with the prototype. The prototype has been able to deliver more than 1.5-kW average output power in a bandwidth larger than 1 GHz.