Low-complexity amplify-and-forward relaying protocol for non-coherent chaos-based communication system

This study proposes a low-complexity amplify-and-forward (AF) relaying scheme for a differential chaos shift keying (DCSK) system. In this scenario, like the conventional AF-DCSK scheme, a source node communicates with a destination node via one relay node, in a way that the source transmits the reference and the data carrier signal to the destination and the selected relay. This approach being sub-optimal, presents a new relaying algorithm for the AF-DCSK scheme to minimise the processing load, the cooperative time and the energy for relaying symbols. Furthermore, it is analytically proven that the new AF scheme benefits from less relaying complexity, and while preserving reasonable power levels, it does not degrade the error performance of the system. Finally, the scheme is evaluated by comparing the transmitted energy, the cooperative time and the error performance gain to the corresponding values in the conventional AF-DCSK scheme.