A link assignment algorithm for GNSS with crosslink ranging

In satellite navigation system using spot beam to build inter-satellite link (ISL) for Autonomous Navigation, each satellite has less number of transceivers than its visible satellites, which poses the natural problem of how to assign these transceivers to point other satellites effectively in order to meet the both crosslink ranging and data exchange requirements of Autonomous Navigation. This paper provides a topology model applicable for both requirements. Based the topology model, this paper presents a link assignment algorithm which is designed to maximize the quantity of crosslink ranging information periodically and to improve the communication performance of inter-satellite network simultaneously. Although some communication performance loss is inevitable to perform link assignment for crosslink ranging, the simulation results show that the algorithm gives better communication performance than mesh-link link assignment which is adopted in Iridium system in up to 80 percent of each satellite period.