Cooperative spatial multiplexing with joint incremental selective relaying

Inefficient use of spectrum is one of the main drawbacks of cooperative protocols that employ half-duplex relay nodes. In this paper, for a multi-relay cooperative network with decode-and-forward (DF) relaying, we propose a spectrally-efficient protocol based on the cooperative spatial multiplexing (C-SM) technique in conjunction with a combination of incremental and selective relaying schemes. The proposed scheme makes use of spectrum as efficiently as possible by minimizing the duration of the second hop transmission. We analyze the performance of the protocol in terms of the outage probability, the average rate and the diversity-multiplexing tradeoff. The simulation results show that the proposed scheme significantly outperforms the conventional relaying schemes in terms of the outage probability and the average rate.