A Ka-band MMIC Power Amplifier in 100-nm GaN-on-Si technology for Space Applications

This contribution reports the design and preliminary on-wafer characterization of a Ka-band MMIC power amplifier (PA) for an earth observation application using a commercial 100-nm GaN-on-Si technology. Design solutions adopted to deal with constraints and challenges posed by space-grade requirements are discussed in detail. In particular, when adopting a Si substrate, thermal management becomes a major issue, requiring the design to be conceived for low power dissipation. Simulation results of the designed amplifier are in line with the state-of-the-art, with an output power in excess of 10W in the 34 GHz to 37 GHz range, with associated PAE and gain close to 30% and 20 dB, respectively. On-wafer measurements in pulsed conditions confirm the output power capability, but also show some criticisms that need further investigation.