Cooperative MIMO network, which consists of multiple relay nodes equipped with a single antenna, is introduced in this paper. Virtual MIMO is examined with multi-relay cooperative communication. Performances of Distributed Space-Time Block Code (DSTBC) in cooperative MIMO are analyzed and compared with general cooperative diversity protocols. Diversity multiplexing tradeoff (DMT), outage probability of DSTBC and pair-wise error probability (PEP) of virtual MIMO with DSTBC are derived in detail with equation denotation presented. Numerical Results of DMT and outage performance indicate that, DSTBC could provide full spatial diversity in two cooperative nodes, and it outperforms other cooperative protocols such as Amplify-and-Forward (AF) and Selection Decode and Forward (SDF) with the increase of cooperative nodes. Meanwhile, Monte Carlo simulation of average error performance in cooperative MIMO network reveal that, with the increase of cooperative nodes, DSTBC could obtain both spatial diversity gain and coded gain. In addition, higher order modulation with the increased number of relays could also enhance BER performance in multi-relay cooperative MIMO network. Theoretical results are confirmed by means of simulations.
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