Performance analysis of distributed space-time coded cooperative multicast

Cooperative multicast/broadcast technique which can improve performance of traditional wireless multicast communications system has been paid a broad attention. However, in 2-hop Cooperative multicast system [8], it is easy to arise interference in destination node if all the nodes who decode message correctly in phase 1 forward information to other users simultaneously. In this paper, to solve this problem, we propose the distributed space-time coded cooperative multicast (DSTC- CM) scheme based on coded cooperation, where the base station (BS) sends a part of the information and the relays transmit the rest. The system performance is improved by making use of coding gain provided by the DSTC coded cooperation. The capability of the proposed scheme is evaluated in terms of the outage probability and diversity-multiplexing tradeoff (DMT). The closed-form of the average outage probability is derived. Asymptotic behavior of the average outage probability in high SNR regions is analyzed and it confirms that the proposed scheme is efficient in the sense of achieving full diversity. Finally, we compare the average outage probability and DMT for different transmission protocols in the simulations.