Network coding based cooperative device-to-device communications in the uplink of cellular network

In this paper we introduce an scheme which combines device-to-device communications nodes which act as relays for a cellular user (CU) located on the cell boundary. The proposed system works as an overlay cellular network. The CU having weak channel towards the base station exploits the availability of a pair of wireless terminals intending to communicate directly with each other. These intermediate device-to-device communications users use network coding to forward CUs´ information to the base station. In addition, they use the same network coded information for exchange of mutual information between themselves. This strategy not only increases the numbers of concurrent transmissions within the common cell but it also, using the same spectrum, offloads the base station which as a results can serve other demanding users within the cells and improve the overall efficiency of the network. We use outage probability as a performance metric to evaluate the performance of the proposed scheme and show that the proposed scheme performs better then space time and repetition coding based cooperative communications.