
2017 年 1 月 Journal on Communications January 2017
2017009-1
第 38 卷第 1 期 通 信 学 报 Vol.38
No.1
基于用户配合的全双工蜂窝系统保密传输方案
康小磊,季新生,夏路,黄开枝
(国家数字交换系统工程技术研究中心,河南 郑州 450002)
摘 要:全双工人工噪声机制在干扰功率持续增加时性能提升受限,并且损失了双工增益。针对上述 2 个问题,
提出一种基于用户配合的全双工蜂窝系统保密传输方案,半双工的用户上行发送的同时,与其配合的用户可以进
行下行发送。蜂窝基站使用全双工技术实现配合用户的干扰消除,并且采用部分功率发送人工噪声干扰窃听者。
在此基础上以最大化系统保密速率为目标,设计下行用户期望信号矢量与人工噪声波束矢量;并且利用一维线性
搜索获得最优功率配比。仿真结果表明,参考 RS-ref 方法和 HD 方法,所提方法能获得的系统保密速率呈线性增
长,并且能够获得全双工增益。
关键词:保密通信;同时同频全双工;用户配合;人工噪声;功率分配
中图分类号:TN925 文献标识码:A
Full duplex secret transmission scheme based on user cooperation
KANG Xiao-lei, JI Xin-sheng, XIA Lu, HUANG Kai-zhi
(China National Digital Switching System Engineering & Technological R&D Center, Zhengzhou 450002, China)
Abstract: Full-duplex artificial noise scheme can achieve a limited improvement while the interference power keeps
increasing and the full-duplex gain is null. To solve these two problems, a full-duplex secure transmission scheme
based on user cooperation was proposed, in which the full-duplex receiver used partial power to send artificial noise,
and transmitted the downlink signal by the remaining power to the user who shared the same frequency. In order to
maximize the system secrecy rate, the beam vector of the desired signal and the artificial noise were designed. Besides,
the optimal power allocation factor was obtained by one-dimensional search simply. Simulation results show that
compared with the RS-ref and HD methods, the proposed method can achieve an approximate linear growth in high
power and can obtain the full-duplex gain.
Key words: secret communication, co-frequency co-time full duplex, user coordination, artificial noise, power allocation
1 引言
无线通信技术的蓬勃发展造成个人数据和信
息进行愈加频繁和大范围的交互共享,因此,面临
被窃听的安全问题越发突出。现有的基于人工噪声
的物理层安全技术
[1]
通过无线信道特性实现对用户
信号的天然保护,但是人工噪声技术需要发送方天
线较多。显而易见地,未来蜂窝通信(5G)中大规模
天线基站的使用将为人工噪声的利用带来巨大的
机遇
[2]
。但是,受限于体积、功耗等因素,终端目
前难以做到多天线,因此,蜂窝通信的上行安全问
题已成为制约蜂窝系统安全性的关键所在。
蜂窝上行链路窃听问题可以建模为 SIMOME
模型,即发送方单天线,接收方和窃听方都为多天
线,现有的大部分安全方案都集中于 MISOME
[3~5]
、
MIMOME
[6,7]
等场景,而对于 SIMOME 场景,大多
借助于外部节点的协作辅助达到类似的多天线效
果
[8,9]
。文献[8]在完美信道状态信息假设下,研究
收稿日期:2016-05-28;修回日期:2016-11-18
基金项目:国家自然科学基金资助项目(No.61379006, No.61401510, No.61471396, No.61501516, No.61521003);国家高技术研究
发展计划(“863”计划)基金资助项目(No.2014AA01A704)
Foundation Items: The National Natural Science Foundation of China (No.61379006, No.61401510, No.61471396, No.61501516,
o.61521003), The National High Technology Research and Development Program of China (863 Program) (No.2014AA01A704)
doi:10.11959/j.issn.1000-436x.2017009