Design and construction of 100W solid state pulse amplifier by using CW amplifier modules

This article describes the first stage in designing and realizing three 100W C-band power amplifier alternatives based on the GaAs-technology for use in TT&C-transmitters. The operational frequency range spanned from 4.3GHz to 4.5GHz. A Gysel power divider was used to feed each branch in the second stage. The amplifiers were capable of delivering 100W output power. This distributed design of the microwave SSPA results in built in redundancy and graceful degradation of output power should any individual PA section fail. Each branch includes a current sense alarm indication which is monitored and fed to the RF SSPA controller. The amplified outputs of all the symmetric branches are summed up in a passive combing network which routes the resultant high power to the output of the RF SSPA.