Integer Linear Programming Based Topology Design for GNSSs With Inter-Satellite Links

Inter-satellite links (ISLs) can be employed in global navigation satellite systems (GNSSs) for space-based telemetry, telecommand and ranging, which reduces the requirement for a large number of ground stations (GSs). However, the polling time division duplex (PTDD) ranging hierarchy of the ISLs raises the topology design problem of the networks. To optimize the communication performance with the constraint of ranging for precise orbit determination in GNSSs, we model the ISLs network with finite state automation (FSA) and solve the optimization problem with integer linear programming (ILP). With the proposed method, for the first time, optimal delay and throughput are both achieved for data transmission between satellites and GSs with guaranteed ranging performance. Simulation results corroborate that, compared with two existing methods, the proposed scheme largely improves the communication performance, i.e., the average delay and the network throughput by 46.9% and 11%, respectively.