2016/10/13 by Ahmed Alkhateeb, Alkhateeb, Ahmed, Geert Leus +3
Computer Science · Engineering · #Advanced MIMO Systems Optimization #Antenna Design and Analysis #Cooperative Communication and Network Coding #FOS: Computer and information sciences #Full-Duplex Wireless Communications #Information Theory (cs.IT)
paper · pdf · doi:10.48550/arxiv.1610.04192
openalex publication_date 2016/10/13 · openalex created_date 2022/10/04 · openalex updated_date 2026/07/28
Massive multiple-input multiple-output (MIMO) systems achieve high sum\nspectral efficiency by offering an order of magnitude increase in multiplexing\ngains. In time division duplexing systems, however, the reuse of uplink\ntraining pilots among cells results in additional channel estimation error,\nwhich causes downlink inter-cell interference, even when large numbers of\nantennas are employed. Handling this interference with conventional network\nMIMO techniques is challenging due to the large channel dimensionality.\nFurther, the implementation of large antenna precoding/combining matrices is\nassociated with high hardware complexity and power consumption. In this paper,\nwe propose multi-layer precoding to enable efficient and low complexity\noperation in full-dimensional massive MIMO, where a large number of antennas is\nused in two dimensions. In multi-layer precoding, the precoding matrix of each\nbase station is written as a product of a number of precoding matrices, each\none called a layer. Multi-layer precoding (i) leverages the directional\ncharacteristics of large-scale MIMO channels to manage inter-cell interference\nwith low channel knowledge requirements, and (ii) allows for an efficient\nimplementation using low-complexity hybrid analog/digital architectures. We\npresent a specific multi-layer precoding design for full-dimensional massive\nMIMO systems. The performance of this precoding design is analyzed and the\nper-user achievable rate is characterized for general channel models. The\nasymptotic optimality of the proposed multi-layer precoding design is then\nproved for some special yet important channels. Numerical simulations verify\nthe analytical results and illustrate the potential gains of multi-layer\nprecoding compared to traditional pilot-contaminated massive MIMO solutions.\n