Modified Q-Aware Scheduling Algorithm for Improved Fairness in 802.16J Networks

摘要

Deployment of Multi-hop Relays in WiMax based Cellular Networks is considered as a cost effective solution to increase the Coverage area of Base Station and also to improve the Network Capacity with high quality short links. Scheduling became a challenging task in these Multi-hop Relay Wireless Cellular Networks of IEEE 802.16j standard. H. Chen, X. Xie and H. Wu proposed a Q-aware Scheduling Algorithm in which back-pressure flow control mechanism is used to reflect current Q size of the Relays and considered high back-pressure links to include in Concurrent Transmission Scenarios, to maximize the throughput. This focus on high back-pressure links, leads to starvation of Mobile Stations having low back-pressure links, resulting unfairness in some cases. To remedy this situation, a Fair Link Inclusion (FLI) mechanism is applied in Greedy Algorithm of Q-aware Scheduling Algorithm. Simulation results show that Modified Q-aware Scheduling Algorithm with FLI mechanism has reasonable improvement in fairness and maintaining steady throughput when compared with existing algorithms.