100W X-band GaN SSPA for medium power TWTA replacement

This paper reports an X-band solid-state power amplifier with an initial output power of 180W at 9.5 GHz and greater than 100 watts measured over an 8 to 11 GHz bandwidth after burn-in. These SOA results were achieved by combining 16 GaN amplifier modules in a low-loss spatial power combiner network. The combining structure has shown a port to port loss of 0.25-0.75 dB from 8GHz to 12 GHz. The 16-way combiner demonstrates an overall combining efficiency of 90%. The size of the 16-way amplifier/combiner is 2.2" dia. × 6" length. This work represents the widest bandwidth operation of a GaN combiner technology to applications at X-band, and establishes new levels of power and efficiency for solid-state power amplifiers operating at these bandwidths.