An assessment of satellite-to-satellite tracking applied to satellite clusters

A satellite cluster, meaning a collection of two or more satellites located in geostationary orbit within a longitude deadband typical of a single satellite, presents special orbit control problems. In order to control the relative motion between satellites by means of thruster firings subject to execution errors, there is a requirement to determine the relative orbits within specified time intervals. The ability of an on-board tracking system to achieve this is examined. A least-squares error analysis of short range satellite-to-satellite tracking between cluster members is presented. From this, the tracking system requirements are assessed, and hardware options are briefly considered.