Multiclass Satellite Payload for SAR

This work investigates a multiclass spaceborne Synthetic Aperture Radar (SAR) payload architecture aimed at enabling distributed and scalable Earth Observation missions using NanoSats and/or MicroSats in cooperative satellite swarms. The proposed architecture addresses the challenge of achieving high performance SAR imaging within the inherent mass, volume and power constraints of small satellites while supporting advanced mission concepts such as SIMO/MIMO operation, formation flying and onboard artificial intelligence driven data processing.
Central to this architecture is a compact SAR Electronic Subsystem (SES) developed by ARESYS in the frame of SATURN mission of Italian Space Agency (ASI). It has been designed for 16U/16UXL NanoSats to be used with deployable 1 sqm reflector antenna and further evolved and adapted to <120 kg MicroSats to be used with a deployable 5 sqm reflector antenna. Beyond standalone operation, it enables coordinated multi satellite acquisitions where multiple spacecraft function collectively as a distributed SAR antenna. This configuration allows the decomposition of traditional monolithic SAR systems into clusters of smaller, more resilient units. In distributed MIMO mode, imaging performance scales with swarm size enabling enhanced resolutions and an increase in accessible swath width.
The SES is composed of modular modules including the SAR board computer, a high power supplier, an up/down conversion chain, transmit–receive modules. Overall, it achieves total mass below 6 kg, a volume up to 6 dm³ and a max power consumption of less than 125 W, making it compatible with small satellite platforms while supporting X band SAR imaging with mission relevant performance.
Overall, this multiclass SAR payload framework supports agile, high performance and cost efficient small satellite missions contributing to the development of next generation distributed Earth Observation systems in low Earth orbit.