Network coding scheme with multi-rate transmission in 802.11 DCF wireless networks

Recently network coding has been proven as a very promising technique to improve wireless network throughput. In multi-rate wireless networks, simply seeking more coding opportunities or coding more packets into one frame without exploiting multi-rate feature may lead to selecting low-rate links for transmission, and thus compromise the performance gain brought by network coding. In this paper, we aim at exploiting the potential benefits brought by both multi-rate and network coding. We carefully address the bottleneck problem in applying network coding to multi-rate networks, and propose an multi-rate COPE-like network coding scheme, which is called COPE-MR and employs the Multi-rate Rate Adaptation(MRA) algorithm. It implements COPE with some extension to allow it to work in multi-rate environment. Simulation experiments results based on NS-2 demonstrate that COPE-MR can significantly improve network performances in terms of both throughput and end-to-end delay in 802.11 DCF multi-rate environment, at a relatively low cost of signaling overhead.