Compact and High Efficiency UHF SSPA for Communication Satellites

This paper presents design, development and measured performance of compact and high efficiency 100W UHF SSPA for satellite on-board applications. The SSPA is designed using GaN HEMTs for medium power and high power amplifier stages and includes diode based power detector for providing RF power telemetry. The SSPA produces 100W output power with worst case efficiency of 60% under all operating temperatures and has a low power dissipation of 70W. Being a space hardware, the designed SSPA follows all derating guidelines to meet the required performance and has a maximum device channel temperature within $150 ^{\circ}\mathrm{C}$ with worst case device compression of 1.5 dB. The realized SSPA also has a compact footprint of 250 mm x 170 mm.