Computing the Receive Spatial Correlation for a Multi-Cluster MIMO Channel Using Different Array Configurations

Spatial correlation among received signals has a significant impact on the performance of a multiple- input multiple-output (MIMO) system. In prior research, expressions were derived for the spatial correlation between the signals received at a uniform linear array (ULA) by assuming that the propagation environment has a single cluster, low angular spread or that the received rays arrive only along the broadside of the array. In this paper, analytical expressions are derived for the spatial correlation between the received signals of a ULA and uniform circular array without making any of the above mentioned assumptions. The derivation can be extended to suit most planar antenna array configurations. This makes the derived expressions valid for most practical propagation channels. Finally, we show using simulations that the derived expression evaluates spatial correlation more accurately than the existing models.