70W GaN-HEMT Ku-Band Power Amplifier in MIC Technology

In this paper the design, implementation, and experimental results of a Ku-band 70W GaN-HEMT power amplifier (PA) for satellite communication are presented. A two-stage design approach with two 250nm bare-die devices has been chosen to achieve a considerably high saturated gain of 15 dB over the whole extended Ku-band (13.75-14.5 GHz). The circuit was realized in a hybrid microwave integrated circuit technology on an alumina substrate. The PA shows a measured performance of more than 50W output power for a continuous-wave signal with a power-added efficiency (PAE) higher than 23%. Modulated measurements demonstrate an average output power of more than 30W (70W peak) and 21% PAE, while holding the Eutelsat linearity requirements.