Footprint handover rerouting protocol for low Earth orbit satellite networks

Abstract

Low Earth Orbit (LEO) satellite networks will be an integral part of the next generation telecommunications infrastructures. In a LEO satellite network, satellites and their individual coverage areas move relative to a fixed observer on Earth. To ensure that ongoing calls are not disrupted as a result of satellite movement, calls should be transferred or handed over to new satellites. Since two satellites are involved in a satellite handover, connection route should be modified to include the new satellite into the connection route. The route change can be achieved by augmenting the existing route with the new satellite or by completely rerouting the connection. Route augmentation is simple to implement, however the resulting route is not optimal. Complete rerouting achieves optimal routes at the expense of signaling overhead. In this paper, we introduce a handover rerouting protocol that maintains the optimality of the initial route without performing a routing algorithm after intersatellite handovers. The FHRP makes use of the footprints of the satellites in the initial route as the reference for rerouting. More specifically, after an optimum route has been determined during the call establishment process, the FHRP ensures that the new route due to handover is also optimum. The FHRP demands easy processing, signaling, and storage costs. The performance results show that the FHRP performs similar to a network without any handovers in terms of call blocking probability.