Performance of massive MIMO V-BLAST with channel correlation and imperfect CSI

In an uplink massive multiple-input-multiple-output (MIMO) deployment with distributed single-antenna users and a large base-station array, we consider the performance of Vertical Bell Laboratories Layered Space Time (V-BLAST) with maximum ratio combining (MRC) and V-BLAST with zero forcing (ZF). In the performance evaluation, we include the effects of imperfect channel state information (CSI) and channel correlation since these system imperfections are of particular importance in massive MIMO. The main contribution is that the performance of MRC V-BLAST is shown to approach that of ZF V-BLAST under a range of imperfect CSI levels, different channel powers and different types of array, as long as the channel correlations are not too high.