An Alamouti transmission scheme with low relay complexity for cooperative communication systems

This paper addresses a novel Alamouti space-time transmission scheme with low relay complexity for cooperative communication systems. While the conventional scheme requires additional time-reversal operation at the relay nodes, increasing the complexity of the relay nodes to obtain the Alamouti coded form at the destination node, the proposed scheme employs a combination of the data symbols at the source node achieving the second order cooperative diversity. From simulation results, it is shown that, with the lower relay complexity than that of the conventional scheme, the proposed scheme achieves the second order cooperative diversity and has the same bit error rate (BER) performance as the conventional scheme.