Multiservice traffic allocation in LEO satellite communications

Satellite communication promises potential methods for providing global communication. In particular, by the development of a Low Earth Orbital (LEO) satellite constellation, both global coverage and broadband communication will be accessible. Problems arise in situations where various traffic types in broadband communication require different levels of quality of service (QoS). Traffic control is required to make sure that each traffic demand may receive the ex-pected QoS. Another problem is that the dynamic topology of a LEO satellite network requires a traffic allocation control, which is able to allocate traffic demand into the Inter Satellite Links (ISLs) between LEO satellites.

In this thesis, traffic allocation strategy in a dynamic LEO satellite communication network is studied and analyzed. The delivery of Quality of Service (QoS) is an important objective. Traffic allocation control is performed in the LEO satellite constellation to provide a near op-timal utilization of these ISLs. An alternative solution is proposed in this research, in which a combination of two algorithms will be used to allocate traffic in this dynamic satellite net-work. The first algorithm allocates traffic during small time intervals, based on an assumption that the topology is unchanged during these intervals. The second algorithm allocates traffic after topology updating has been accomplished. Traffic allocation respects some constraints including QoS (due to multiservice requirements), capacity constraints, traffic distribution, and availability constraints. Both theoretical and empirical studies have been undertaken to exam-ine the performance of the proposed algorithm, denoted GALPEDA (Genetic Algorithm Linear Programming and Extended Dijkstra Algorithm). The proposed algorithm provides privileges to a class of high priority traffic, including benefits for traffic allocation of multiclass traffic in LEO satellite communication. It provides a novel traffic allocation mechanism to cope with the dynamic topology of a LEO satellite; moreover this algorithm distributes multiservice traffic evenly over the network. Simulations results are provided.