A Novel Admission Control for Multimedia LEO Satellite Networks

Low Earth Orbit (LEO) satellite networks are deployed as an enhancement to terrestrial wireless networks in order to provide broadband services to users regardless of their location. In addition to global coverage, these satellite systems support communications with hand-held devices and offer low cost-per-minute access cost, making them promising platforms for personal communication services (PCS). LEO satellites are expected to support multimedia traffic and to provide their users with some form of quality of service (QoS) guarantees. However, the limited bandwidth of the satellite channel, satellite rotation around the Earth and mobility of end-users makes QoS provisioning and mobility management a challenging task. One important mobility problem is the intra-satellite handoff management. While global positioning systems (GPS)-enabled devices will become ubiquitous in the future and can help solve a major portion of the problem, at present the use of GPS for low-cost cellular networks is unsuitable. RADAR - refined admission detecting absence region - a novel call admission control and handoff management scheme for LEO satellite networks is proposed in this chapter. A key ingredient in this scheme is a companion predictive bandwidth allocation strategy that exploits the topology of the network and contributes to maintaining high bandwidth utilization. Our bandwidth allocation scheme is specifically tailored to meet the QoS needs of multimedia connections. The performance of RADAR is compared to that of three recent schemes proposed in the literature. Simulation results show that our scheme offers low call dropping probability, providing for reliable handoff of on-going calls, and good call blocking probability for new call requests, while ensuring high bandwidth utilization.