Capacity approaching turbo coding for half duplex relaying

In this paper, we develop capacity approaching turbo coding schemes for half-duplex relay systems as an extension of our previous work on the full-duplex relay systems. We design the codes to be used at the source and the relay nodes, and develop an information combining technique at the destination node. In addition, by utilizing information theoretical results, we compute the optimal fraction of time during which the relay node should listen, and use it in the design of capacity approaching coding/decoding schemes. We observe that the performance of the practical coding schemes proposed is about 1.2 dB away from the theoretical limits (for a variety of channel models)