Relaying Strategies for Cooperative Networks with Minimal Node Communications

Distributed space-time-block-coding (Dis-STBC) achieves diversity through cooperative transmission among geographically dispersed nodes. In this paper, we evaluate the performance of several decentralized Dis-STBC schemes in a selective decode-and-forward two-stage relaying network. In particular, we consider schemes without a central control unit or inter-node communications. These include a pre-assignment strategy and two randomized transmission techniques. The average diversity order of these techniques is considered, and the outage performance is presented under realistic channel conditions. It is found that although the randomized Dis-STBC has the best average diversity order, the performance difference of these schemes is negligible under more realistic scenarios. In addition, the effect of the power distribution between stages and between nodes is evaluated