Coding scheme based on multi‐dimensional constellations for relay‐assisted multi‐user system
Ying Chun Huang, Jing Lei · IET Communications · 2016
For relay‐assisted system, better relay channel and instable direct transmission (DT) channel exist. The recent coding schemes always focus on how to improve the system performance when channels are in medium signal‐to‐noise ratios. For the instability of DT channel, a novel coding scheme with multi‐dimensional constellations at relay is proposed, which make use of the robust relay channel. The design rule based on best approximate performance is given in the form of an optimisation problem, and its general solution is also shown. In addition, the optimal relay‐coding matrix design for 8PSK and 16QAM has been discussed in detail. Simulation results show that the authors’ proposed coding scheme outperforms the conventional scheme with repetition and is more robust than other well designed schemes in confronting the instability of DT channel.