Symbol Mapping Optimization for Cooperative Systems with a Hybrid Search Algorithm

Abstract

Cooperative diversity is an important method that has been widely studied in the recent years. In this scheme, a source node wishing to transmit data to a destination node can benefit from other nodes in its neighborhood (relay nodes) to forward copies of the original signal to the destination. However, the performance of cooperative systems can be significantly improved by using the constellation rearrangement technique (CoRe), in which different signal constellations are used in different retransmissions. In this context, this paper proposes the use of a hybrid search algorithm, which uses genetic mutation and clonal selection, to perform the optimization of the constellation mapping. The performance evaluation of the algorithm shows that a good performance is achieved when compared to other approaches outlined in the literature.