Abstract:
Satellite communication systems (SatCom) are undergoing a major transition. An industry long dominated by a limited number of heavy geostationary (GEO) satellites is shifting its focus to many small satellites in low earth orbit (LEO). The reduction in the cost of launching objects into space and the advent of small satellites are enabling a process of democratizing access to space. As a result, over two thousand satellites were launched in 2023 alone, and a launch rate of 8 satellites per day is expected until 2032. The satellite itself is undergoing a profound transformation from a transparent reflector with rigid constraints to a regenerative flexible system with onboard processing capabilities, enhancing legacy services and opening to new space applications. However, the typical architecture of satellite communications based on monolithic satellites presents certain difficulties in meeting the requirements of future satellite network services. Clusters, fractionated systems, swarms, and, more generally, distributed satellite systems (DSS) replace a monolithic satellite with a coordinated system of multiple small satellites. They create large virtual antenna apertures, leading to a significant increase in spatial resolution, better frequency reuse, and greater fault tolerance.