Smart Cooperative System Using Orthogonal Signaling with Signal Space Diversity

Abstract

In this paper, an efficient cooperative transmission scheme with signal space diversity is proposed for two-user cooperative systems. In contrast with the conventional cooperative scheme based on orthogonal signaling, the proposed scheme obtains signal space diversity by utilizing rotated constellation. Because the proposed scheme provides much information to receiver in decoding process, a receiver can decode information more accurately. Therefore, the proposed scheme improves the bit error rate performance in severe fading channel environments. Simulation results demonstrate that the performance of the proposed scheme is especially superior to the performance of the conventional scheme in low inter-user channel quality.