Scalability Aspects of Cell-Free Massive MIMO

Giovanni Interdonato; Pål Frenger; Erik G. Larsson

doi:10.1109/icc.2019.8761828

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arXiv · 1902.11275

Scalability Aspects of Cell-Free Massive MIMO

Giovanni Interdonato·Pål Frenger·Erik G. Larsson

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Abstract

Ubiquitous cell-free massive MIMO (multiple-input multiple-output) combines massive MIMO technology and user-centric transmission in a distributed architecture. All the access points (APs) in the network cooperate to jointly and coherently serve a smaller number of users in the same time-frequency resource. However, this coordination needs significant amounts of control signalling which introduces additional overhead, while data co-processing increases the back/front-haul requirements. Hence, the notion that the "whole world" could constitute one network, and that all APs would act as a single base station, is not scalable. In this study, we address some system scalability aspects of cell-free massive MIMO that have been neglected in literature until now. In particular, we propose and evaluate a solution related to data processing, network topology and power control. Results indicate that our proposed framework achieves full scalability at the cost of a modest performance loss compared to the canonical form of cell-free massive MIMO.

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Giovanni Interdonato, Pål Frenger, Erik G. Larsson. 2019-02-28. Scalability Aspects of Cell-Free Massive MIMO. https://doi.org/10.1109/icc.2019.8761828

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