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Resource Management in Satellite Networks part 26

Resource Management in Satellite Networks part 26. This book provides significant knowledge on innovative radio resource management schemes for satellite communication systems that exploit lower layer adaptivity and the knowledge of layer 3 IP QoS support and transport layer behavior. The book integrates competencies considering all the parts of system design: propagation aspects, radio resource management, access protocols, network protocols, transport layer protocols, and more, to cover both broadband and mobile satellite systems | 234 Tommaso Pecorella Giada Mennuti into account whereas in the second one other motion components like Earth rotation and user movements are considered. The key idea of the algorithm is that in order to prevent handover failure during a call bandwidth will be reserved in a particular number S of spot-beams that the call would handover into. In 38 a probabilistic resource reservation strategy for real-time services was proposed. The sliding window concept is adopted to predict the necessary amount of reserved bandwidth for a new call in its future handover spot-beams. As for real-time services a new call request is accepted if the originated spot-beam has available bandwidth and resource reservation is successful in future handover spot-beams. As for non real-time service new call requests are accepted if the originated spot-beam satisfies its maximum required bandwidth. In 6 39 a selective look-ahead strategy is proposed where real-time and non-real time service classes are differently treated. Bandwidth allocation only pertains to real-time connection handovers. To each accepted connection bandwidth allocation is performed in a look-ahead horizon of k cells along its trajectory. This algorithm offers low call dropping probability i.e. a reliable management of call handovers of and acceptable call blocking probability for new calls. 7.4 Conclusions This Chapter has presented a set of dynamic bandwidth allocation techniques and identified associated research topics. We can conclude this Chapter by highlighting these two types of DBA problems and related techniques Handover-constrained techniques mainly used for LEO satellites where the main problem is to acquire a resource among a number of different satellites since the communication lifetime is long enough to require a number of handovers Bandwidth-constrained techniques affecting mainly GEO systems where the main issue is to cope with the high delay-bandwidth product that makes the reactive approaches unfeasible