Coverage optimization of satellite formations using Instantaneous overlap area

Formation flying techniques are increasingly adopted in Earth observation. Measurements relevant to the same areas and collected at the same time as in the case of bistatic radar can generate different and richer products than a single platform does. An important parameter to be considered while designing a spacecraft mission is the coverage area granted by the spacecraft, also referred to as the access area. The instantaneous access area is a measure of the extent of the Earth’s surface that a satellite can see at any given instant. When it comes to a formation of satellites, we are more interested in the concept of instantaneous overlap area which is a measure of area on the Earth’s surface that can be serviced by 2 or more satellites simultaneously. Notwithstanding the effects of orbital perturbations, a defined relative geometry among spacecraft belonging to the formation should be maintained to ensure the requested coverage overlap. This paper deals with control algorithms that can be introduced and applied to maximize the instantaneous overlap area, therefore increasing the reliability of measurements all along the mission duration.