Analysis of rate optimized throughput for large-scale MIMO-(H)ARQ schemes

In this paper, we consider throughput and rate optimized throughput for large-scale MIMO-(H)ARQ systems in i.i.d. complex Gaussian block fading channels. Exact analysis of large-scale MIMO is generally intractable, yet the field of random matrix theory has provided asymptotic expressions for the instantaneous channel capacity, which we propose for studying MIMO-(H)ARQ systems. Even with those expressions, closed-form results for the maximum throughput and optimal rate are not known. We therefore provide i) tight asymptotic lower and upper bounds, with a diminishing gap, for the optimal rate that is useful for the design of practical link adaptation algorithms, and ii) a tight asymptotic lower bound for the maximized throughput, suggesting the practical sufficiency of MIMO-ARQ, without any packet combining, over more complex MIMO-HARQ methods.