基于MBM和大规模MIMO的物理层安全问题研究

发布时间：2018-06-30 08:13

  本文选题：物理层安全 + MBM调制　； 参考：《浙江大学》2017年硕士论文

【摘要】：无线通信技术的不断发展使得传输安全面临严峻考验。物理层安全作为一种在实际应用中开销合理、切实可行的无线通信安全机制,正受到越来越多的关注。物理层安全利用信道随机性确保非法对手无法获取合法信息。这种基于信息论和信号处理实现数据安全传输的技术,为信息安全领域提供了新的研究思路。而探索基于新型无线通信技术的物理层安全问题,具有重要的研究价值。媒介调制(Media-BasedModulation,MBM)是一种新型调制方式,它利用丰富的散射环境产生一系列信道,并将发送信息包含在传输媒介中。该调制利用无线信道随机性和独特性的核心思想与物理层安全一致,因此可以研究基于该调制提高物理层安全的方法。大规模多输入多输出(Multiple Input Multiple Output,MIMO)技术是一种具有频谱及功率效率优势的新兴无线通信技术。通过在基站覆盖区域布置数十根或上百根天线,它能极大地提升频谱效率和数据传输速率。但是大量天线对物理层安全的作用却很少有研究关注。本学位论文针对MBM系统和大规模MIMO系统特点,围绕基于两种系统的物理层安全问题展开,具体研究内容如下:在讨论MBM系统物理层安全问题之前,我们首先研究该系统的基本原理、基本模型和接收检测方法,为后续研究打下基础。与传统的相移键控(Phase Shift Keying,PSK)、正交振幅调制(Quadrature Amplitude Modulation,QAM)等源调制(Source-Based Modulation,SBM)不同,MBM的核心思想是将发送信息包含在传输媒介中,即利用信道的随机性和独特性来发送不同消息。所有传输信道将映射形成接收星座图。文中首先研究了该调制系统的基本原理,然后介绍了单输入和多输入两种类型的MBM系统及其传输特性,并提出该调制下接收机一种可行的信号检测算法。针对MBM系统的物理层安全问题,我们主要研究存在单个被动窃听对手的情况下,提升系统安全性的方法。根据MBM系统可以自由选择大量传输信道的特点,我们提出了基于信道选择来提升系统安全性能的方法,且该方法没有在收发端之间进行信道信息传输的要求。基于不同前提条件,我们提出了三种信道选择方案,分别为理想条件下最优信道选择、实际条件下可行信道选择和人工噪声(Artificial Noise,AN)辅助信道选择三种方案。我们详细研究并仿真分析了三种信道选择方案的保密中断概率和保密级数,并比较了其对安全性的提升作用。仿真结果证明,由于MBM有大量待选发送信道,只要通过一定条件的信道选择,就能大幅提高系统的安全性能。我们研究了基于大规模MIMO系统的物理层安全问题。首先我们介绍了大规模MIMO系统的通信窃听模型。该模型条件下,我们分析了多天线对手使用不同接收方式,并分别采用被动窃听和主动攻击导频及数据部分时对系统保密速率的影响。通过对系统保密速率、保密中断概率和保密级数的推导分析可知,由于大规模MIMO基站布置了大量天线并使用预编码,被动窃听和针对数据部分的主动攻击对系统的安全性能几乎不会造成影响。因此主动攻击成为威胁大规模MIMO系统安全性的有效手段。我们进一步研究了大规模MIMO基站针对主动攻击的检测方法。在分析已有的能量检测法和导频相关法之后,我们提出了一种将能量检测与导频相关相结合的简易算法。仿真结果证明我们的算法具有鲁棒性,并能够有效提升检测性能。
[Abstract]:The continuous development of wireless communication technology has made the transmission security face a severe test. Physical layer security, as a reasonable and feasible wireless communication security mechanism in practical applications, is receiving more and more attention. The physical layer is safe to use channel randomness to ensure that illegal hands are unable to obtain legal information. The technology of data security transmission with signal processing provides new research ideas for the field of information security, and it has important research value to explore the physical layer security problem based on new wireless communication technology. Media-BasedModulation (MBM) is a new mode of modulation. It produces a system using a rich scattering environment. The Multiple Input Multiple Output (MIMO) technology is a kind of spectrum and a method for improving the physical layer security based on the modulation, which is the core idea of the radio channel randomness and uniqueness and the physical layer. The power efficiency advantage of the new wireless communication technology. By laying dozens or hundreds of antennas in the base station coverage area, it can greatly improve the frequency efficiency and the data transmission rate. However, there is little research attention on the effect of a large number of antennas on the security of the physical layer. This dissertation focuses on the characteristics of the MBM system and the large-scale MIMO system. Based on the physical layer security problem of two systems, the specific research content is as follows: before discussing the physical layer security problem of the MBM system, we first study the basic principle of the system, the basic model and the reception detection method, which lays the foundation for the follow-up research. And the traditional phase shift keying (Phase Shift Keying, PSK), orthogonal amplitude modulation (Quadra). The ture Amplitude Modulation, QAM) equal source modulation (Source-Based Modulation, SBM) is different. The core idea of MBM is to include the transmission information in the transmission medium, that is to use the randomness and uniqueness of the channel to send different messages. All the transmission channels will be mapped to form a reception constellation. In this paper, the basic original of the modulation system is studied. Then, we introduce two types of MBM systems with single input and multiple inputs and their transmission characteristics, and propose a feasible signal detection algorithm under the modulated receiver. In view of the physical layer security problem of the MBM system, we mainly study the method of improving the security of the system under the presence of a single passive eavesdropping opponent. According to the MBM system, In order to select a large number of transmission channels freely, we propose a method to improve the security performance of the system based on channel selection, and this method does not require channel information transmission between the transceiver. Based on different preconditions, we propose three channel selection schemes, which are the optimal channel selection under ideal conditions, and the actual conditions are practical. The feasible channel selection and the artificial noise (Artificial Noise, AN) auxiliary channel selection are three schemes. We have studied and simulated the secrecy probability and the security series of the three channel selection schemes in detail, and compared its enhancement to the security. The simulation results show that as the MBM has a large number of channels to be selected to send, only through After a certain channel selection, the security performance of the system can be greatly improved. We have studied the physical layer security problem based on the large-scale MIMO system. First, we introduce the communication eavesdropping model of the large-scale MIMO system. Under this model, we analyze the multiple antenna opponents using different reception methods and use passive eavesdropping respectively. And the influence of the active attack on the system secrecy rate and the data part. Through the analysis of the system secrecy rate, the secrecy interrupt probability and the security series, it is found that the large-scale MIMO base station has a large number of antennas and used precoding, the passive eavesdropping and the active attack against the data division are almost not safe to the system. Therefore, active attack is an effective means to threaten the security of large-scale MIMO systems. We have further studied the detection methods of large-scale MIMO base stations for active attack. After analyzing the existing method of energy detection and pilot correlation, we put forward a simple calculation of combining the energy detection with the pilot correlation. Simulation results show that our algorithm is robust and can effectively enhance the detection performance.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN918;TN919.3
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本文编号：2085617