On the robustness of space-time block codes to spatial correlation

In this paper, we generalize the analysis presented originally in [1] to study the robustness of space-time block codes (STBC), paired with linear or circular antenna arrays, to spatial fading correlation. A tight upper bound on the error probability of the scheme is derived based on the distribution of Hermitian quadratic form of complex correlated Gaussian variates. This analytic framework supports various complex orthogonal designs with arbitrary signal cardinalities and arbitrary number of antenna elements. Results indicate that the effective diversity order is retained even when high cross correlation exists and is mainly determined by the geometric mean of the covariance matrix eigenvalues.