Alamouti-Like Transmission Schemes in Distributed MIMO Networks

In this letter, we investigate the potential benefits of using Alamouti-like orthogonal space-time-frequency block codes (STFBC) in distributed multiple-input multiple-output (D-MIMO) systems. We derive a closed-form ergodic spectral efficiency (SE) formula, numerically calculate outage SEs, and propose a centralized method for clustering radio units and user equipment so that a suitable STFBC is applied within each cluster. The results show that STFBCs together with an optimized clustering significantly outperform baseline techniques in terms of both ergodic and outage SE when there is no instantaneous channel state information at the time of transmission.