Backhaul-aware scheduling for WiMAX femtocell with limited backhaul capacity

Abstract

A femtocell is designed to use a shared broadband IP link. A bottleneck may be occurred due to the limitation of provisioned bandwidth and the existence of background traffic especially in access network. The bottleneck will certainly affect the service performance of the femtocell access point (FAP), which would influence end user experience. In order to maintain QoS requirement against backhaul quality fluctuation, a FAP should be equipped with a QoS management capability which is aware of backhaul condition. By applying backhaul aware admission control and scheduling, FAP can determine whether or not the backhaul bandwidth capacity is able to support a new service session. FAP will know the backhaul bandwidth by implementing bandwidth estimation. When the congestion occurred, FAP will maintain the existing flows and accept sessions with higher priority services (i.e realtime) over lower priority traffic (ie. non-realtime), based on load demand of each service flows.