Pairwise Error Probability Performance of SM-MIMO and Spatially Modulated Cooperative Communication Employing SDF Protocol

In this paper, we analyze the performance of spatially modulated (SM) multiple input multiple output (MIMO) system and spatially modulated MIMO cooperative system with multiple relays employing selective decode and forward (SDF) protocol. Here the analysis is done for pre-determined orthogonal channel for SM MIMO and SM MIMO cooperative system using M-PSK modulation and ML detection. Firstly Pairwise error probability (PEP) expression is derived and optimal, sub-optimal detection is done in a spatially modulated MIMO system. Further, the analysis of SDF spatially modulated MIMO cooperative system is extended to single relay and multiple relay configurations. PEP expression is also derived for SDF spatially modulated MIMO cooperative system. Simulation results for the SM MIMO system show optimal detection performs better than suboptimal detection and system performance improves as the number of antenna increases. The simulation results of PEP analysis in the SM MIMO cooperative system include the theoretical PEP, exact PEP and asymptotic PEP and Optimal power allocation (OPA) is also derived for the same. Optimal power allocation for theoretical PEP, exact PEP and asymptotic PEP outperforms the same at equal power allocation