Abstract
Scholars are expected to continue enhancing the depth and breadth of theoretical research on reconfigurable intelligent surface (RIS) to provide a higher theoretical limit for RIS engineering applications. Notably, significant advancements have been achieved through both academic research breakthroughs and the promotion of engineering applications and industrialization. We provide an overview of RIS engineering applications, focusing primarily on their typical features, classifications, and deployment scenarios. Furthermore, we systematically and comprehensively analyze the challenges faced by RIS and propose potential solutions including addressing the beamforming issues through cascade channel decoupling, tackling the effects and resolutions of regulatory constraints on RIS, exploring the network-controlled mode for RIS system architecture, examining integrated channel regulation and information modulation, and investigating the use of the true time delay (TTD) mechanism for RIS. In addition, two key technical points, RIS-assisted non-orthogonal multiple access (NOMA) and RIS-based transmitter, are reviewed from the perspective of completeness. Finally, we discuss future trends and challenges in this field.
摘要
学者们有望继续提高智能超表面(RIS)理论研究的深度和广度, 为RIS工程应用提供更高的理论极限. 通过诸多学术研究的突破以及工程化的推动, RIS技术研究已取得重大进展. 本文首先概述RIS工程应用研究进展, 主要关注其典型技术特性、 分类和部署场景. 然后, 系统、 全面地分析了RIS面临的挑战, 提出潜在解决方案, 包括通过级联信道解耦来解决波束成形问题、 解决RIS调控约束的解决方案、 探索RIS基于网络控制的系统架构、 研究信道调控和信息调制的融合、 研究真时延(TTD)机制在RIS中的使用, 并探讨了RIS辅助非的**交多址接入(NOMA)和基于RIS的发射机. 最后, 讨论了该领域的未来趋势和挑战.
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Yajun ZHAO declares that he has no conflict of interest.
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Project supported by the National Key Research and Development Program of China (No. 2020YFB1807600)
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Zhao, Y. Reconfigurable intelligent surfaces for 6G: applications, challenges, and solutions. Front Inform Technol Electron Eng 24, 1669–1688 (2023). https://doi.org/10.1631/FITEE.2200666
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DOI: https://doi.org/10.1631/FITEE.2200666
Key words
- 6G
- Reconfigurable intelligent surface (RIS)
- Cascade channel decoupling
- RIS regulatory constraint
- RIS system architecture
- True time delay