2018/09/06 by Ikram Boukhedimi, Boukhedimi, Ikram, Abla Kammoun +3 · 1 citation
Engineering · #Advanced MIMO Systems Optimization #Advanced Wireless Communication Techniques #Advanced Power Amplifier Design
paper · pdf · doi:10.48550/arxiv.1809.01872
We carry out a theoretical analysis of the uplink (UL) of a massive MIMO\nsystem with per-user channel correlation and Rician fading, using two\nprocessing approaches. Firstly, we examine the linear minimum-mean-square-error\nreceiver under training-based imperfect channel estimates. Secondly, we propose\na statistical combining technique that is more suitable in environments with\nstrong Line-of-Sight (LoS) components. We derive closed-form asymptotic\napproximations of the UL spectral efficiency (SE) attained by each combining\nscheme in single and multi-cell settings, as a function of the system\nparameters. These expressions are insightful in how different factors such as\nLoS propagation conditions and pilot contamination impact the overall system\nperformance. Furthermore, they are exploited to determine the optimal number of\ntraining symbols which is shown to be of significant interest at low Rician\nfactors. The study and numerical results substantiate that stronger LoS signals\nlead to better performances, and under such conditions, the statistical\ncombining entails higher SE gains than the conventional receiver.\n