Formation control for Sabrina mission

With the purpose of covering bi-static and interferometry applications ASI defining a civilian program. Such a mission will referred as SABRINA, of (System for Advanced Bistatic and Radar INterferometry Applications), is based on the use of a satellite "BisSat" (Bistatic and Interferometric SAR SATellite). The SABRINA mission will operate in very close formation with a reference COSMO-SkyMed satellite without any impact on the satellite products and with the aim to experiment innovative interferometric-bistatics techniques providing additional products. The Italian Space Agency (ASI) is involved in the realization, together with Ministry of Defence (IAD), of the COSMO-Skyemd program that foresees the deployment, in LEO, of a constellation of 4 SAR satellites, dedicated to the management, control and exploitation of Earth resources for civil and defence applications. Alcatel Alenia Space Italia (AAS-I) is the Prime Contractor responsible for the design, development and verification of the entire system. The innovative concept of space missions in formation needs a non conventional orbital control. The measurement of the relative distances, among satellites, can be done using a dedicated GNSS systems. The Integrated Control System, on board BisSat satellite, has been adapted to satisfy resources demand and requirements of systems of satellites in formation, responding to the stringent requirements for the control and management of the formation flying, and the crucial satellite on board autonomy.