摘要
为了对抗电磁干扰与敌方窃听,提出了人工噪声掩护下的跳频通信架构.其中,人工噪声对消是提升系统安全的关键步骤,但实际接收节点处的时间同步误差会降低人工噪声对消效果与系统保密性能.鉴于此,分析了同步误差下人工噪声对消后的残余人工噪声成分和系统保密性能,并提出了具有同步误差鲁棒性的人工噪声最优功率分配方法.理论分析和仿真结果表明,时间同步误差会在人工噪声对消时引入符号间干扰与跳间干扰,进而降低系统的保密性能.此外,当接收节点可以实现完美时间同步时,人工噪声与通信信号应等功率发射.随着时间同步误差的增加,人工噪声与通信信号的功率比应当逐渐减小,以降低时间同步误差引起的保密性能损失.
To counteract electromagnetic interference and hostile wiretapping,an artificial noise-shielded frequency hopping(ANS-FH)architecture is proposed in this paper.In this regard,AN cancellation is a key procedure for secrecy enhancement,but the time-synchronization error between a received signal and the locally reconstructed AN degrades the AN cancellation and system secrecy performance.Given this circumstance,the residual AN components after the cancellation and secrecy performance under the time-synchronization error are analyzed.Based on this analysis,a closed-form optimal transmitting power-allocation(PA)scheme for AN and a confidential signal(CS)is provided to reduce the secrecy loss by synchronization errors.Theoretical and simulation results show that the time-synchronization error in the proposed ANS-FH systems increases the inter-symbol and inter-hop interference during AN cancellation and,thus,degrades the AN cancellation and secrecy performance.Meanwhile,simulations on the proposed PA scheme show that the power ratio of AN to CS should be equivalent when perfect time synchronization is performed and should decrease gradually when the synchronization error increases to counteract the performance degradation by the time-synchronization error.
作者
宋长庆
张译丹
赵宏志
邵士海
Changqing SONG;Yidan ZHANG;Hongzhi ZHAO;Shihai SHAO(National Key Laboratory of Science and Technology on Communications,University of Electronic Science and Technology of China,Chengdu 611731,China)
出处
《中国科学：信息科学》
CSCD
北大核心
2023年第3期550-565,共16页
Scientia Sinica(Informationis)
基金
国家重点研发计划基金(批准号:2018YFB1801903)
国家自然科学基金(批准号:U19B2014,62071094,61901396)资助项目。
关键词
人工噪声
跳频
时间同步误差
噪声对消
功率分配
artificial noise
frequency hopping
time synchronization error
noise cancellation
power allocation
