FLEXGAN · Ka-band GaN-based SSPA for flexible payloads and multicarrier operation for 5G satellite concept

5G demand requires the deployment of Very High Throughput Satellites (vHTS) than can satisfy the expected needs implying a growth opportunity for GEO satellites. This kind of spacecraft offers high capacity, large number of users and communication volumes (1 Terabit/s per satellite), with lower cost per GBPS, increasing the flexibility since the satellite capacity is allocated where it is needed. Future vHTS satellites will make use of Ka/Q/V gateways where the forward payload link will operate in K-band. Traditionally, demand for power at high frequencies has resulted in TWTAs as the logical amplifier of choice; this is due to the fact that traditional SSPA technology was unavailable at similar performance levels. However, technological advancements such as linearization, miniaturisation, and the use of different materials such as GaN, have levelled the playing field for SSPAs. The objective of FLEXGAN is to design, develop and test in a representative space environment (TRL 5) a low cost high power and efficient Ka-band GaN SSPA with RF output power varying capability, with high innovative & low loss recombination schemes and able to operate in multicarrier operation mode for on-board 5G satellite applications. The operational frequency band is 17.3-20.2 GHz and the objective output power 125W. The main innovations that FLEXGAN brings are: 1) Bring known terrestrial technologies by TTI to space; 2) SSPA able to provide the required output power maximising the power added efficiency to compensate the downlink fading losses; 3) SSPA able to transmit in multicarrier mode w/o memory effect; 4) Implementation of highly innovative linearization techniques; 5) use of lighweight composite structures to decrease the weight of the overall SSPA. In order to have a 100% European SSPA an MMIC based on D01GH technology from OMMIC will be designed, manufactured and tested. FLEXGAN will allow to reinforce and corroborate the use of GaN technology for space applications.