ReDEx: Receiver Diversity Exploitation Mechanism for 802.11 Wireless Networks

The authors' objective is to increase the individual throughput of each node in the network by exploiting neighbors with more favorable channel conditions in terms of bit rate and packet loss ratio. They propose a per-neighbor message queue in order to reduce the effect of the Head Of Line (HOL) blocking problem of IEEE 802.11. A weighted queuing scheduler grants each neighbor a service proportional to its channel conditions. The sender maintains a separate back-off counter for each neighbor and adopts a dynamic binding strategy to avoid multiple transmissions to a neighbor with bad channel conditions. They use a continuous time Markov chain model to study the proposed mechanism and to derive the correspondent parameters optimizing the channel utilization.