Design of Wide Band 80 W Solid State Power Amplifier Using GaN HEMT

This paper describes the design & fabrication and measurement results of a wide band(S to C band) 80 W solid state power amplifier(SSPA) using a GaN HEMT. The SSPA is fabricated with wide band impedance matching topology in a balanced combined configuration using two GaN HEMT bare dies and with a super CMC(S-CMC) structure with high thermal conductivity using the eutectic bonding carrier packaging method. The wide band 80 W SSPA, with 42 dBm CW input power injection at operation frequency, demonstrated performance with an average output power of 81.4 W, an average power addition efficiency(PAE) of 36.65%, and an average power gain of 7.1 dB. Furthermore, with 41 dBm CW input power injection at 4.5 GHz frequency, it had a peak output power of 121.9 W, a maximum PAE of 49.16 %, and a maximum power gain of 9.86 dB. To verify the applicability to an electronic warfare jammer, the designed 120 W RF SSPA module was implemented and measured by combining two such wide band 80 W SSPAs in a 90° hybrid coupled power configuration.