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 tra¢ c types in broadband communication require di¤erent levels of quality of service (QoS). Tra¢ c control is required to make sure that each tra¢ c demand may receive the expected QoS. Another problem is that the dynamic topology of a LEO satellite network requires a tra¢ c allocation control, which is able to allocate tra¢ c demand into the Inter Satellite Links (ISLs) between LEO satellites. In this thesis, tra¢ c allocation strategy in a dynamic LEO satellite communication network is studied and analyzed. The delivery of Quality of Service (QoS) is an important objective. Tra¢ c allocation control is performed in the LEO satellite constellation to provide a near optimal utilization of these ISLs. An alternative solution is proposed in this research, in which a combination of two algorithms will be used to allocate tra¢ c in this dynamic satellite network. The …rst algorithm allocates tra¢ c during small time intervals, based on an assumption that the topology is unchanged during these intervals. The second algorithm allocates tra¢ c after topology updating has been accomplished. Tra¢ c allocation respects some constraints including QoS (due to multiservice requirements), capacity constraints, tra¢ c distribution, and availability constraints. Both theoretical and empirical studies have been undertaken to examine 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 tra¢ c, including bene…ts for tra¢ c allocation of multiclass tra¢ c in LEO satellite communication. It provides a novel tra¢ c allocation mechanism to cope with the dynamic topology of a LEO satellite; moreover this algorithm distributes multiservice tra¢ c evenly over the network. Simulations results are provided. Thesis Supervisor: Stephen Sugden Title: Dr, Associate Professor