Network-Controlled Channel Allocation Scheme for IEEE 802.11 Wireless LANs: Experimental and Simulation Study

The increased density of wireless local area network (wireless LAN) access points (APs) based on the IEEE 802.11 standard has induced inter-cell interference that severely degrades system performance. In order to mitigate this issue, this paper proposes an efficient network-controlled channel allocation scheme that can be applied to a managed wireless LAN system with a central coordinator. On the basis of channel monitoring results obtained from APs and data traffic amount at each AP, the central coordinator computes the quasi-optimal frequency channel of each AP in such a way that the given utility function is maximized. Numerous simulations and testbed experiments with UDP traffic flows show that the proposed scheme works well and improves the overall system throughput and fairness among throughput of APs even when there exist uncontrollable APs of other network domains that cannot be controlled by the coordinator.