中国空间科学技术

中国空间科学技术 ›› 2023, Vol. 43 ›› Issue (3): 144-152.doi: 10.16708/j.cnki.1000-758X.2023.0047

• 巨型星座/低轨大规模星座专栏 • 上一篇    

基于方向调制的多目标卫星物理层安全测控技术

王进，张国亭，刘广凯，白真，魏汇赞，孙景云，赵家庆   

  1. 1 北京跟踪与通信技术研究所，北京100094
    2 上海航天电子技术研究所，上海201109
  • 出版日期:2023-06-25 发布日期:2023-05-23

Physical layer security technology for multi-satellite TT&C systems based on directional modulation

WANG Jin，ZHANG Guoting，LIU Guangkai，Bai Zhen，WEI Huizan，SUN Jingyun，ZHAO Jiaqing   

  1. 1 Beijing Institute of Tracking and Telecommunications Technology，Beijing 100094，China
    2 Shanghai Aerospace Electronic Technology Institute，Shanghai 201109，China
  • Published:2023-06-25 Online:2023-05-23

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摘要： 在巨型星座中，航天测控系统需对多目标卫星同时进行测控任务。由于无线信号的广播特性，全空域多波束测控系统在可视弧段内存在多个目标卫星和多个非目标卫星，有用信息在传输过程中易被非目标卫星拦截和窃听，测控链路的物理层安全问题亟待解决。考虑在地面站多波束发射机中引入方向调制技术，通过在发射信号中叠加人工噪声，并针对非目标卫星方向未知和已知两种场景分别设计基于正交投影和基于最大化信泄噪比（maximum signaltoleakageandnoise ratio，MaxSLNR）的波束成形算法，来有效提升测控系统的物理层安全性能。仿真结果表明，两种算法均能使非目标卫星方向上的接收信号星座图产生畸变，同时在目标卫星方向上保持标准的星座图分布。相较而言，正交投影算法更适用于非目标方向未知场景，达到无差别屏蔽非目标卫星方向截获的效果；而MaxSLNR算法综合考虑了对非目标卫星接收机性能的抑制，能够达到定向屏蔽非目标卫星的效果。

关键词: 测控, 方向调制, 物理层安全, 正交投影, 信泄噪比

Abstract: For giant constellations，the space TT&C system needed to serve multiple satellites simultaneously.Due to the broadcasting characteristics of microwave，the information was visible to multiple target satellites and non-target satellites during transmission by the hemispherical coverage multi-target TT&C system.In this process，the confidential messages were easy to be intercepted and eavesdropped by non-target satellites.The directional modulation（DM）technology，as a physical layer security technology，was used to solve this problem.The DM technology was applied for the ground station multi-beam transmitter to enhance the physical layer security.To optimize the beamforming matrices and the superimposed artificial noise vector for transmitted signals，the orthogonal projection method was designed when the directions of the non-target satellites were inaccessible，and the maximum signal-to-leakage-and-noise ratio（Max-SLNR）criterion was applied when the directions of the non-target satellites were available.It follows from the simulation results that both algorithms can distort the received signal constellation pattern in the directions of the non-target satellites，while maintaining the standard constellation pattern in the directions of the target satellites.In contrast，the orthogonal projection algorithm is more suitable without the directions of the non-target satellites，to achieve the undifferentiated interception effect for non-target satellite directions.However，the Max-SLNR algorithm can directionally interfere the receivers of non-target satellites with known directions.

Key words: TT&, C；directional modulation；physical security；orthogonal projection；SLNR