Practical compress-and-forward cooperation for the classical relay network

This paper proposes a practical compress-and-forward cooperation scheme with vector coding at the relay node for a three-terminal classical relay network. We discuss the framework of the relay receiver and analyse two practical vector coding algorithms for the cooperation, nearest neighbour quantization and lattice vector quantization. The error rate performance of the compress-and-forward cooperation and some other protocols under different SNRs is investigated. The impact of the quantization rate at the relay node is also characterised. It is shown that for a quantization rate larger than 2 bits/sample, the vector coding whether employing nearest neighbour quantization or lattice vector quantization, outerforms both the decode-and-forward protocol and scalar coding.