Performance analysis of space-time block codes over generalized-K fading MIMO channels

This paper elaborates on the performance of orthogonal space-time block codes (STBCs) for multiple-input multiple-output (MIMO) systems operating in generalized-K fading conditions. The considered fading model is generic since it intimately encompasses both small-scale fading (modeled via the Nakagami-m distribution) and large-scale fading (modeled via the gamma distribution). In the following, new exact analytical expressions are derived for the Shannon capacity along with asymptotic expressions in the high and low Signal-to-Noise ratio (SNR) regimes. We also present exact tractable expressions followed by first-order expansions for the marginal outage probability and symbol error rate (SER); further, we quantify the performance of STBCs in terms of diversity order and coding gain. The derived analytical expressions are validated via a set of Monte-Carlo simulations which also demonstrate the implications of the model parameters on the overall performance.