A cooperative transmission scheme based on symbol constellation expansion over multipath fading channels

In this paper, we propose a novel cooperative transmission scheme based on a symbol constellation expansion over Rayleigh and Rician multipath fading channels. The proposed scheme expands the symbol constellation through a unique combination of the original symbols, thus increasing the minimum distance among the single points. We also analyze the bit error rate (BER) performance showing that the proposed scheme achieves the fourth order diversity. Numerical results demonstrate that the proposed scheme not only achieves the fourth order cooperative diversity, but also has a better BER performance than those of the conventional schemes.