Opportunistic relay selection for wireless network coding

Owing to its potential of enhancing the network performance and to the large number of applications it can be suited for, wireless network coding is attracting a lot of interest from both the academic and the industrial communities. A common assumption in most of the literature is the presence of a single intermediate relay node where the network coding operation takes place. However, in an actual wireless system, a multitude of relaying nodes would exist, thus potentially further improving the performance; but with this the issue of relay selection arises. In this paper we study the performance of network coding in presence of opportunistic relay selection. We conjecture that relay selection schemes should be aware of, and account for, the network coding operation in case of its presence. Based on system level simulation results, it is demonstrated that such an awareness provides considerable capacity gains as compared to its traditional opportunistic counterparts, in addition to increased fairness among the encoded sources.