Spectral-Efficiency Analysis of Massive MIMO Systems in Centralized and Distributed Schemes

• Published in: IEEE transactions on communications Vol. 64; no. 5; pp. 1930 - 1941
• Main Authors: Kamga, Gervais N., Minghua Xia, Aissa, Sonia
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.05.2016; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna arrays; Antenna location optimization; centralized and distributed MIMO; Channel models; Correlation; Fading; massive MIMO; MIMO; Shadow mapping; spectral efficiency; massive MIMO; centralized and distributed MIMO; Antenna location optimization; spectral efficiency
• ISSN: 0090-6778; 1558-0857
• DOI: 10.1109/TCOMM.2016.2519513

This paper analyzes the spectral efficiency of massive multiple-input multiple-output (MIMO) systems in both centralized and distributed configurations, referred to as C-MIMO and D-MIMO, respectively. By accounting for real environmental parameters and antenna characteristics, namely, path loss, shadowing effect, multipath fading, and antenna correlation, a novel comprehensive channel model is first proposed in closed-form, which is applicable to both types of MIMO schemes. Then, based on the proposed model, the asymptotic behavior of the spectral efficiency of the MIMO channel, under both the centralized and distributed configurations is analyzed and compared in exact forms, by exploiting the theory of very long random vectors. Afterwards, a case study is performed by applying the obtained results into MIMO networks with circular coverage. In such a case, it is attested that for the D-MIMO of cell radius r c and circular antenna array of radius r a, the optimal value of r a that maximizes the average spectral efficiency is accurately established by r a opt = r c /1.31. Monte Carlo simulation results corroborate the developed spectral-efficiency analysis.