The orbit dynamics of satellite clusters

The demand for space communications capacity is predicted to increase during the next decade. New space segment concepts are required to meet these demands. One design is the satellite cluster in which a number of satellites are co-located in near-geostationary orbit. The individual satellites cannot be resolved by a communications ground station. The available cluster geometries are reviewed and their properties examined. Orbit evolution of the cluster is discussed together with the implications for absolute and relative station keeping and tracking. An assessment is made of the feasibility of cluster operations and the maintenance of inter-satellite links. Areas requiring further attention are outlined.