Satellite formation, a mobile sensor network in space

Several currently planned space missions consist of a set of satellites flying in a formation. This enables a much higher functionality of the mission compared to missions consisting of only a single satellite. On the other hand, this introduces several new problems, especially in the handling of the formation. Besides their geometric structure, the formation of satellites also has a communication network among the satellites which is the basis for the cooperative behavior, in order to accomplish the overall aim of the mission. The sensors present in each of the satellite enable sensing and communication between the satellites and form a wireless network. This gives rise to a mobile sensor network in space and hence many challenges with it. The topology of this communication in the mobile sensor network can be a bottleneck in the operation of the formation because the transmission of information and the efficient coordination of the formation relies on this topology. This is particularly the case for a large number of satellites in the network. In this paper we study the relative stability of communicating sensor topologies as a key characteristic of the formation of satellites and their behavior as a wireless sensor network in space.