On the uplink of large-scale MIMO systems with correlated ricean fading channels

In this work, we focus on the uplink (UL) of a single-cell large-scale multi-user MIMO system where K mono-antenna users communicate with a BS equipped with N antennas. This latter estimates the Ricean correlated channels based on training symbols and uses maximum-ratio- combining or linear-minimum-mean-square-error receivers for signal processing. Assuming a fixed number of users with an asymptotic antenna regime, we derive closed-form approximations of the achievable UL rates as a function of the system's parameters, the Ricean factors and the training sequence's length. Accordingly, these expressions are instructive in how the aforementioned parameters impact the performances. Plus, a different processing approach using only the statistics of the channels is investigated and found to be a judicious choice when the Ricean factor is high enough. Although our analytical results are based on a large antenna-limit, we show by simulations that they provide very accurate approximations even for finite system dimensions.