Encyclopedia of Wireless Networks

Living Edition
| Editors: Xuemin (Sherman) Shen, Xiaodong Lin, Kuan Zhang

Cell-Free Massive MIMO

  • Hien Quoc NgoEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-32903-1_137-1



Cell-free massive multiple-input multiple-output (MIMO) is a system comprising a very large number of access points (hundreds or thousands of access points) and a relatively smaller number of active users (tens or hundreds of users) distributed over a large area. The access points use directly measured channel characteristics to jointly serve all users in the same time-frequency band. There are no cells or cell boundaries.

Historical Background

Conventional mobile networks are based on cellular structure where a coverage area is divided into cells, and each cell is served by one access point/base station. These networks are called “cellular wireless networks.” We have seen many revolutions related to the cellular wireless network since its first trial was introduced in the 1970s (Young, 1979). Intercell interference is one of the inherent limitations of cellular networks. In particular, users at the cell boundaries perform badly due to the...

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Electronics, Electrical Engineering and Computer ScienceQueen’s University BelfastBelfastUK

Section editors and affiliations

  • Wei Zhang
    • 1
  1. 1.School of Electrical Engineering and TelecommunicationsThe University of New South WalesSydneyAustralia