Exact pairwise error probability analysis of space-time codes in spatially correlated fading channels

In this paper, we derive an analytical expression for the exact pairwise error probability (PEP) of a space-time coded system operating over a spatially correlated slow fading channel using a moment-generating function-based approach. This analytical PEP expression is more realistic than previously published exact-PEP expressions as it fully accounts for antenna spacing, antenna geometries (uniform linear array, uniform grid array, uniform circular array, etc.) and scattering models (uniform, Gaussian, Laplacian, Von-Mises, etc.). Inclusion of spatial information provides valuable insights into the physical factors determining the performance of a spacetime code. We demonstrate the strength of our new analytical PEP expression by evaluating the performance of two spacetime trellis codes proposed in the literature for different spatial scenarios. Keywords— Gaussian Q-function, modal correlation, momentgenerating function, MIMO system, non-isotropic scattering, space-time coding.