A predictive call admission control scheme for low earth orbit satellite networks

In many recent low earth orbit (LEO) satellite networks, intersatellite lin ks (ISLs) are used to enhance the capability of the networks, The ISLs are continuously deleted and established since the visibility between satellite s changes over time. These topological changes require rerouting of the tra ffic on ISLs, which unavoidably involves dropping of some ongoing calls, Tn general, such an ongoing call dropping degrades the quality-of-service (Qo S) more severely than an initiated fall blocking In this paper, rye propose a call admission control scheme that allows a flexible tradeoff between dr opped ongoing calls and blocked initiated calls. The call admission control scheme makes use of two techniques: traffic recasting and traffic projecti on. The traffic recasting maps the current traffic onto the network after t he topological change whereas the traffic projection projects the recast tr affic from the current time to the time of the topological change. The proj ected traffic is used to estimate the increase in ongoing call dropping who se QoS penalty is compared against that of increased newly initiated call b locking to make the cap admission decision. Simulation results show that th e proposed call admission control scheme significantly reduces the ongoing call dropping probability with only a marginal increase in the initiated ca ll blocking and call completion probabilities.