High power and efficiency power combining of space TWTAs with waveguide magic-T for Satellite communication

A high efficiency power combining demonstration is presented in this paper of 2 X-band TWTAs based on magic-T corporate combiner. A low loss, amplitude and phase balanced, high isolation and power waveguide magic-T combiner is designed. Power combining efficiencies of greater than 90% and output power of more than 85W over a 0.7GHz frequency band are successfully demonstrated by introducing phase shifter and variable attenuator within input end. Such combiner can also be taken as an element within a corporate combining architecture of more TWTAs for much high efficiency and power outputting for satellite communication.