Towards Near-Field Communications for 6G: Challenges and Opportunities

doi:10.12142/ZTECOM.202401002

ZTE Communications ›› 2024, Vol. 22 ›› Issue (1): 3-15.DOI: 10.12142/ZTECOM.202401002

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Towards Near-Field Communications for 6G: Challenges and Opportunities

LIU Mengyu¹, ZHANG Yang¹, JIN Yasheng¹, ZHI Kangda², PAN Cunhua¹()

^1.Southeast University, Nanjing 210096, China
^2.Queen Mary University of London, London E1 4NS, UK

Received:2023-11-30 Online:2024-03-28 Published:2024-03-28
About author:LIU Mengyu received his BE degree from the School of Electronic and Information Engineering, Beijing Jiaotong University, China in 2023. He is currently pursuing his ME degree with the School of Information Science and Engineering, Southeast University, China. His research interests include massive MIMO, reconfigurable intelligent surfaces (RIS), and near-field communications.
ZHANG Yang received his BE degree from the Harbin Institute of Technology, China in 2023. He is currently pursuing his ME degree with the School of Information Science and Engineering, Southeast University, China. His research interests include reconfigurable intelligent surfaces (RIS), array signal processing, near-field communications, and localization.
JIN Yasheng received his BE degree from the Bell Honors School, Nanjing University of Posts and Telecommunications, China in 2023. He is currently pursuing his ME degree with the School of Information Science and Engineering, Southeast University, China. His research interests include massive MIMO, reconfigurable intelligent surfaces (RIS), machine learning and near-field communications.
ZHI Kangda received his BE degree from the School of Communication and Information Engineering, Shanghai University, China in 2017, ME degree from School of Information Science and Technology, University of Science and Technology of China in 2020, and PhD degree from the School of Electronic Engineering and Computer Science, Queen Mary University of London, UK in 2023. His research interests include reconfigurable intelligent surface (RIS), massive MIMO, and near-field communications. He received the Exemplary Reviewer Certificate of the IEEE Wireless Communications Letters in 2021 and 2022.
PAN Cunhua (cpan@seu.edu.cn) received his BS and PhD degrees from the School of Information Science and Engineering, Southeast University, China in 2010 and 2015, respectively. From 2015 to 2016, he was a research associate at the University of Kent, UK. He held a post-doctoral researcher position at the Queen Mary University of London, UK from 2016 to 2019, where he was a lecturer from 2019 to 2021. Since 2021, he has been a full professor with Southeast University. His research interests include reconfigurable intelligent surfaces (RIS), intelligent reflection surface (IRS), ultra-reliable low latency communication (URLLC), machine learning, UAV, the Internet of Things, and mobile edge computing. He has published over 120 IEEE journal articles. He received the IEEE ComSoc Leonard G. Abraham Prize and IEEE ComSoc Asia-Pacific Outstanding Young Researcher Award both in 2022.
Supported by:
National Key Research and Development Young Scientist Project 2023YFB2905100, the National Natural Science Foundation of China(62201137);the Fundamental Research Funds for the Central Universities(2242022k60001);the Research Fund of National Mobile Communications Research Laboratory, Southeast University, China(2023A03)

Abstract

Abstract:

Extremely large-scale multiple-input multiple-output (XL-MIMO) and terahertz (THz) communications are pivotal candidate technologies for supporting the development of 6G mobile networks. However, these techniques invalidate the common assumptions of far-field plane waves and introduce many new properties. To accurately understand the performance of these new techniques, spherical wave modeling of near-field communications needs to be applied for future research. Hence, the investigation of near-field communication holds significant importance for the advancement of 6G, which brings many new and open research challenges in contrast to conventional far-field communication. In this paper, we first formulate a general model of the near-field channel and discuss the influence of spatial nonstationary properties on the near-field channel modeling. Subsequently, we discuss the challenges encountered in the near field in terms of beam training, localization, and transmission scheme design, respectively. Finally, we point out some promising research directions for near-field communications.

Key words: near-field communications, extremely large-scale antenna arrays, spatial non-stationarity, beam training, localization

LIU Mengyu, ZHANG Yang, JIN Yasheng, ZHI Kangda, PAN Cunhua. Towards Near-Field Communications for 6G: Challenges and Opportunities[J]. ZTE Communications, 2024, 22(1): 3-15.

Figures/Tables 10

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Towards Near-Field Communications for 6G: Challenges and Opportunities

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