近场通信物理层安全技术综述

徐勇军; 李晶; 骆东鑫; 王骥; 李兴旺; 杨龙; 陈莉

doi:10.11999/JEIT250336

近场通信物理层安全技术综述

doi: 10.11999/JEIT250336 cstr: 32379.14.JEIT250336

徐勇军^{1, 2},
李晶¹,
骆东鑫¹,
王骥^3, ,,
李兴旺⁴,
杨龙⁵,
陈莉¹

1.
重庆邮电大学通信与信息工程学院重庆 400065
2.
东南大学毫米波国家重点实验室南京 210096
3.
华中师范大学物理科学与技术学院武汉 430079
4.
河南理工大学物理与电子信息学院焦作 454003
5.
西安电子科技大学通信工程学院西安 710000

基金项目: 国家自然科学基金(62271094)，重庆市自然科学基金(CSTB2022NSCQ-LZX0009, CSTB2023NSCQLZX0079)，重庆市青年创新人才计划(CSTB2024NSCQ-QCXMX0059)，湖北省重点研发计划项目(2023BAB061)，中央高校基本业务费(CCNU25ai026)，东南大学毫米波重点实验室开放课题(KN202502-07)

详细信息

作者简介:
徐勇军：男，教授，研究方向为RIS、通感一体化等

李晶：男，硕士生，研究方向为近场通信、物理层安全

骆东鑫：男，硕士生，研究方向为反向散射通信、RIS

李兴旺：男，副教授，研究方向为通感一体化、RIS等

杨龙：男，教授，研究方向为无线物理层安全和协作通信等

陈莉：女，工程师，研究方向为反向散射通信、RIS

通讯作者:
王骥　jiwang@ccnu.edu.cn

中图分类号: XXXX
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- 文章访问数: 17
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- 被引次数: 0
出版历程
- 修回日期: 2025-09-17
- 网络出版日期: 2025-09-23

A Survey on Physical Layer Security in Near-Field Communication

XU Yongjun^{1, 2},
LI Jing¹,
LUO Dongxin¹,
WANG Ji^{3
, ,},
LI Xingwang⁴,
YANG Long⁵,
CHEN Li¹

1.
School of Communications and Information Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China
2.
State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
3.
College of Physical Science and Technology, Central China Normal University, Wuhan 430079, China
4.
School of Physics and Electronic Information Engineering, Henan Polytechnic University, Jiaozuo 454003, China
5.
School of Communication Engineering, Xidian University, Xi’an 710000, China

Funds: National Natural Science Foundation of China (62271094), Natural Science Foundation of Chongqing (CSTB2022NSCQ-LZX0009, CSTB2023NSCQLZX0079), New Chongqing Youth Innovative Talent Program (CSTB2024NSCQ-QCXMX0059), Key Research and Development Program of Hubei Province under Grant (2023BAB061), Fundamental Research Funds for the Central Universities of China under grant (CCNU25ai026), Open Research Fund of State Key Laboratory of Millimeter Waves, Southeast University (KN202502-07)

摘要

摘要: 近场通信作为未来移动通信的关键方向，凭借其低时延及高精度定位等特性，成为6G网络演进的重要支撑。针对现有物理层安全技术仍集中在远场通信，该文系统梳理了6G近场通信物理层安全的研究进展，深入分析其核心技术与挑战。首先，阐述了近场通信的信道特性及与远场的本质区别，介绍了近场通信的体系架构，提出保密容量、保密速率等物理层关键性能指标。其次，针对不同目标与传输环境，总结了基于波束聚焦、人工噪声及多技术融合的物理层安全技术。再次，进一步探讨了视距、非视距及混合远近场环境下的安全传输策略。然后，指出复杂信道建模、安全与性能平衡及多网融合抗干扰等未来挑战。最后，对近场通信物理层安全的未来研究方向进行了展望，对推动近场通信物理层安全发展及标准化具有重要参考价值。
- 近场通信 /
- 物理层安全 /
- 6G /
- 波束聚焦
Abstract: Significance Traditional wireless communication systems have relied on far-field plane-wave models to support wide-area coverage and long-distance transmission. However, emerging Sixth-Generation (6G) applications—such as extended reality, holographic communication, pervasive intelligence, and smart factories—demand ultra-high bandwidth, ultra-low latency, and sub-centimeter-level localization accuracy. These requirements exceed the spatial multiplexing gains and interference suppression achievable under far-field assumptions. Enabled by extremely large-scale antenna arrays and terahertz technologies, the near-field region has expanded to hundreds of meters, where spherical-wave propagation enables precise beam focusing and flexible spatial resource management. The additional degrees of freedom in the angle and distance domains, however, give rise to new Physical Layer Security (PLS) challenges, including joint angle–distance eavesdropping, beam-split-induced information leakage caused by frequency-dependent focusing, and security–interference conflicts in hybrid near- and far-field environments. This paper provides a comprehensive survey of near-field PLS techniques, advancing theoretical understanding of spherical-wave propagation and associated threat models while offering guidance for designing robust security countermeasures and informing the development of future 6G security standards. Progress This paper presents a comprehensive survey of recent advances in PLS for near-field communications in 6G networks, with an in-depth discussion of key enabling technologies and optimization methodologies. Core security techniques, including beam focusing, Artificial Noise (AN), and multi-technology integration, are first examined in terms of their security objectives. Beam focusing exploits ultra-large-scale antenna arrays and the spherical-wave propagation characteristics of near-field communication to achieve precise spatial confinement, thereby reducing information leakage. AN introduces deliberately crafted noise toward undesired directions to hinder eavesdropping. Multi-technology integration combines terahertz communications, Reconfigurable Intelligent Surfaces (RIS), and Integrated Sensing And Communication (ISAC), markedly enhancing overall security performance. Tailored strategies are then analyzed for different transmission environments, including Line-of-Sight (LoS), Non-Line-of-Sight (NLoS), and hybrid near–far-field conditions. In LoS scenarios, beamforming optimization strengthens interference suppression. In NLoS scenarios, RIS reconstructs transmission links, complicating unauthorized reception. For hybrid near–far-field environments, multi-beam symbol-level precoding spatially distinguishes users and optimizes beamforming patterns, ensuring robust security for mixed-distance user groups. Finally, critical challenges are highlighted, including complex channel modeling, tradeoffs between security and performance, and interference management in converged multi-network environments. Promising directions for future research are also identified, such as Artificial Intelligence (AI)-assisted security enhancement, cooperative multi-technology schemes, and energy-efficient secure communications in near-field systems. Conclusions This paper provides a comprehensive survey of PLS techniques for near-field communications, with particular emphasis on enabling technologies and diverse transmission scenarios. The fundamentals and system architecture of near-field communications are first reviewed, highlighting their distinctions from far-field systems and their unique channel characteristics. Representative PLS approaches are then examined, including beam focusing, AN injection, and multi-technology integration with RIS and ISAC. Secure transmission strategies are further discussed for LoS, NLoS, and hybrid near–far-field environments. Finally, several open challenges are identified, such as accurate modeling of complex channels, balancing security and performance, and managing interference in multi-network integration. Promising research directions are also outlined, including hybrid near–far-field design and AI-enabled security. These directions are expected to provide theoretical foundations for advancing and standardizing near-field communication security in future 6G networks. Prospects Research on PLS for near-field communications remains at an early stage, with no unified or systematic framework established to date. As communication scenarios become increasingly diverse and complex, future studies should prioritize hybrid far-field and near-field environments, where channel coupling and user heterogeneity raise new security challenges. AI-driven PLS techniques show strong potential for adaptive optimization and improved resilience against adversarial threats. In parallel, integrating near-field PLS with advanced technologies such as RIS and ISAC can deliver joint improvements in security, efficiency, and functionality. Moreover, low-power design will be essential to balance security performance with energy efficiency, enabling the development of high-performance, intelligent, and sustainable near-field secure communication systems.
- Near-field communication /
- Physical Layer Security (PLS) /
- 6G /
- Beam focusing

HTML全文

图 1 近场通信应用图

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图 2 文章内容逻辑结构

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图 3 近场通信和远场通信

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图 4 近场通信和远场通信MISO系统模型

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图 5 近场通信采用节点放置部署架构

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图 6 近场通信采用网络层部署架构

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图 7 近场和远场安全传输的比较

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图 8 面向不同传输场景下的近场通信模型

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图 9 基于多技术融合的近场通信模型

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图 10 LoS环境下近场通信模型

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图 11 NLoS环境下近场通信模型

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图 12 混合远近场环境下通信模型

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图 13 关键技术与挑战性问题的关系

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表 1 近场通信基于不同角度部署对比

类别	部署优势	技术复杂性	应用场景
节点部署	灵活动态调整节点位置配置	较低主要考虑远近效应	智慧城市和物联网等通过节点部署实现可靠通信
网络层部署	高效显著提升通信系统性能	较高涉及复杂信道处理和网络复杂度	无人驾驶和车联网等同时进行感知和数据传输场景

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表 2 基于不同目标的近场通信物理层安全技术对比

物理层安全技术	优点	缺点	应用场景
波束聚焦	增强物理层安全以及提升保密性能	技术实现复杂、对信道模型的准确性要求高	物理层安全、无线能量传输和多用户通信中的干扰缓解
人工噪声	抗干扰能力强、无需共享密钥、保密性强	涉及复杂信道处理和网络复杂度	广播通信系统、物理层安全
多技术融合	降低能耗、提升性能可以适用多种场景	算法复杂度高、信道估计难度大	智能家居、医疗健康以及智能交通等领域

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表 3 不同近场通信物理层安全技术的对比和联系

关键技术	安全机制	频谱效率	复杂度	融合形式
波束聚焦	空间隔离	高	中实时波束优化	接收器中心保护区域叠加人工噪声
人工噪声	信号干扰	低	低仅需功率分配	波束聚焦引导人工噪声分布
多技术	空间信号联合优化	高	高需联合多技术协同优化	ISAC结合动态波束调控

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表 4 基于不同传输环境的近场通信物理层安全技术的对比

传输环境	优点	缺点	应用场景
近场LoS环境	信号质量好、波束聚焦效果佳及定位精度高	覆盖范围受限、易受干扰及部署成本高	工业物联网、智能医疗及智能交通管理等
近场NLoS环境	信号传输灵活性高、环境适应能力强等	信号衰减严重、系统复杂度增加及多径干扰严重	城市峡谷间的车联网通信、室内复杂环境下的设备互联
混合远近场	覆盖范围广、适应未来通信需求	技术实现难度大、安全挑战增加及信道估计困难	通感融合技术

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