A Tutorial on Extremely Large-Scale MIMO for 6G: Fundamentals, Signal Processing, and Applications

By Zhe Wang, Jiayi Zhang, Hongyang Du, Dusist Niyato, Shuguang Cui, Bo Ai, Merouane Debbah, Khaled Ben Letaief, H. Vincent Poor. IEEE Communications Surveys and Tutorials, 2023

499 citations recorded by the source corpus.

Extremely large-scale multiple-input-multiple-output (XL-MIMO), which offers vast spatial degrees of freedom, has emerged as a potentially pivotal enabling technology for the sixth generation (6G) of wireless mobile networks. With its growing significance, both opportunities and challenges are concurrently manifesting. This paper presents a comprehensive survey of research on XL-MIMO wireless systems. In particular, we introduce four XL-MIMO hardware architectures: uniform linear array (ULA)-based XL-MIMO, uniform planar array (UPA)-based XL-MIMO utilizing either patch antennas or point antennas, and continuous aperture (CAP)-based XL-MIMO. We comprehensively analyze and discuss their characteristics and interrelationships. Following this, we introduce several electromagnetic characteristics and general distance boundaries in XL-MIMO. Given the distinct electromagnetic properties of near-field communications, we present a range of channel models to demonstrate the benefits of XL-MIMO. We further discuss and summarize signal processing schemes for XL-MIMO. It is worth noting that the low-complexity signal processing schemes and deep learning empowered signal processing schemes are reviewed and highlighted to promote the practical implementation of XL-MIMO. Furthermore, we explore the interplay between XL-MIMO and other emergent 6G technologies. Finally, we outline several compelling research directions for future XL-MIMO wireless communication systems.

Subfields: Aerospace Engineering, Electrical and Electronic Engineering

View Paper: https://www.semanticscholar.org/paper/4378fea4ae93bdf6b43900b5b087e0a04153a629

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The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

D. Morales-Jiménez
Pablo Ramírez-Espinosa
F. R. Ghadi
Kin-Fai Tong
Junhui Rao
Hao Xu
Chan-Byoung Chae
Ross D. Murch

Citations in the corpus

A Tutorial on Fluid Antenna System for 6G Networks: Encompassing Communication Theory, Optimization Methods and Hardware Designs (2024, background): “Researchers are naturally encouraged to explore XL-MIMO, where the basic idea is to deploy an extremely large number of antennas in a compact space in which the antenna aperture could be discrete or continuous [64].”
The Integrated Sensing and Communication Revolution for 6G: Vision, Techniques, and Applications (2024, unknown): “…number of antennas at least an order of magnitude, e.g., several hundreds or even thousands of antennas, thus obtaining electrically large aperture arrays (ELAAs) and unprecedentedly improving the spectral efficiency and spatial resolution for wireless communication and sensing [229], [230], [231].”
A Tutorial on Near-Field XL-MIMO Communications Toward 6G (2023, unknown): “The appealing beneﬁts of XL-MIMO have spurred active research recently, and several overviews [51], [64]–[69] and survey/tutorial [8], [28], [41], [70], [71] papers on XL-MIMO have appeared, which are summarized in Table I for ease of reference.”