2015/05/14 by Xueru Li, Li, Xueru, Emil Björnson +7
Computer Science · Engineering · Mathematics · #Advanced MIMO Systems Optimization #Advanced Wireless Communication Techniques #FOS: Computer and information sciences #Information Theory (cs.IT) #Wireless Communication Networks Research #cs.IT #math.IT
paper · pdf · doi:10.48550/arxiv.1505.03682
31 pages, 9 figures, submitted to IEEE Trans. Wireless Commun
openalex publication_date 2015/05/14 · arxiv created 2015/05/26 · arxiv updated 2015/05/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this paper, a new state-of-the-art multi-cell MMSE scheme is proposed for massive MIMO networks, which includes an uplink MMSE detector and a downlink MMSE precoder. The main novelty is that it exploits all available pilots for interference suppression. Specifically, let K and B denote the number of users per cell and the number of orthogonal pilot sequences in the network, respectively, where β= B/K is the pilot reuse factor. Then our multi-cell MMSE scheme utilizes all B channel directions, that can be estimated locally at each base station, to actively suppress both intra-cell and inter-cell interference. The proposed scheme is particularly practical and general, since power control for the pilot and payload, imperfect channel estimation and arbitrary pilot allocation are all accounted for. Simulations show that significant spectral efficiency (SE) gains are obtained over the single-cell MMSE scheme and the multi-cell ZF, particularly for large β and/or K. Furthermore, large-scale approximations of the uplink and downlink SINRs are derived, which are asymptotically tight in the large-system limit. The approximations are easy to compute and very accurate even for small system dimensions. Using these SINR approximations, a low-complexity power control algorithm is also proposed to maximize the sum SE.