Maximizing Multiuser Diversity Gains in IEEE 802.11 WLANs

Opportunistic scheduling monitors the receivers' channel states and schedules packets to the receivers in relatively good channel conditions. Opportunistic scheduling can be easily implemented in cellular network systems that have embedded channel state report functions. To apply opportunistic scheduling to wireless LANs, deficient of channel report functions, the authors first devise an efficient channel probing mechanism. Prior opportunistic scheduling methods for WLANs limit the number of probed receivers and may not fully utilize the potential multiuser diversity gains. In this paper, they develop a new opportunistic scheduling scheme called WDOS (WLAN Distributed Opportunistic Scheduling). WDOS invites all receivers to channel probing and has a potential to fully realize the multiuser diversity gains.