CORELA: A cooperative relaying enhanced link adaptation algorithm for IEEE 802.11 WLANs

One of the key challenges for cooperative relaying multi-rate wireless networks is the integration and interaction of relaying with link adaptation algorithms, in particular under incomplete and/or imprecise channel state information conditions. In this paper we propose a practical cooperative relaying link adaptation medium access protocol that considers the historical link quality to enable the relay terminal to adjust its transmission relaying rate by estimating the error probability based on past packet transmission history. Simulation results show that this protocol achieves significant performance improvement in terms of end-to-end throughput and energy efficiency for different network conditions compared with other link adaptation algorithms. It also has the best performance of the direct transmission without perfect knowledge of current channel condition.