| 摘要: |
| 非正交多址接入（Non-orthogonal Multiple Access，NOMA）的核心在于在同一无线资源上为多个用户同时提供服务以提高频谱效率。然而，由于资源的共享，NOMA存在安全漏洞。针对这一问题，提出了一个近场安全传输框架，并设计了一种两阶段波束成形优化策略以对抗内部窃听。该策略首先基于半正定松弛（Semi-definite Relaxation,SDR）将原始问题中的非凸约束转化为等价的半正定松弛形式，再利用连续凸逼近（Successive Convex Approximation,SCA）将处理后的原始问题转化为一系列的连续凸问题，并通过逐步迭代来逼近原始问题的最优解。仿真结果显示，相较于远场通信，该近场安全传输框架能显著提高信息传输的安全性，具体表现为在基站最大传输功率下，信息传输的平均保密率提高了约28%。 |
| 关键词: 非正交多址(NOMA) 近场通信；波束成形；物理层安全 |
| DOI：10.20079/j.issn.1001-893x.241230001 |
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| 基金项目:湖北省教育厅科学技术研究计划重点项目（D20232503） |
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| Analysis of Physical Layer Security Strategies for NOMA Systems in Near-field Scenarios |
| DUAN Lilia,LIU Xueyub,WANG Yinghuib,ZHANG Lei |
| (1a.School of Computer and Information Engineering,1b.School of Physics and Electronic Science,Hubei Normal University,Huangshi 435000,China;2.School of Electrical and Information Engineering,Hubei Polytechnic University,Huangshi 435000,China) |
| Abstract: |
| The core of non-orthogonal multiple access(NOMA) lies in providing simultaneous service to multiple users on the same wireless resources to enhance spectral efficiency.However,due to resource sharing,NOMA is susceptible to security vulnerabilities.To address this issue,a near-field secure transmission framework is proposed,along with a two-stage beamforming optimization strategy designed to counteract internal eavesdropping.In the first stage,based on semi-definite relaxation(SDR),the original problem's non-convex constraints are transformed into an equivalent semi-definite relaxation form.In the second stage,utilizing successive convex approximation(SCA),the processed original problem is transformed into a series of continuous convex problems,approaching the optimal solution of the original problem through iterative steps.Simulation results show that,compared with far-field communication,this near-field secure transmission framework significantly improves the security of information transmission.Specifically,under the maximum transmission power of the base station,the average secrecy rate of information transmission is increased by approximately 28%. |
| Key words: non-orthogonal multiple access(NOMA) near-field communication beamforming physical layer security |
《电讯技术》编辑部 