理想与非理想信道条件下物理层安全传输的理论与性能分析

发布时间：2018-07-02 15:02

本文选题：物理层安全传输 + 非理想信道估计　；参考：《电子科技大学》2017年硕士论文

【摘要】：物理层安全技术摒弃了基于计算复杂度不可行的传统安全方法,创新地利用无线噪声信道内在的随机的独特性和不可复制性,以信道噪声为“密钥”实现无线数据传输的安全性。然而,现有针对物理层安全传输的研究大多是假设信道状态信息理想的前提下进行的,但在实现应用中信道估计误差不可避免,在实际无线通信系统中得到的都是非理想信道状态信息。基于理想信道状态信息的物理层安全传输研究缺乏对非理想因素的适应能力,因而与实际系统存在差异,无法实现目标安全性。基于上述问题的考虑,本论文以提高无线通信的安全性为目标,研究非理想信道估计条件下的物理层安全传输系统性能,主要研究工作如下:1.研究基于MIMO窃听信道模型的“无条件安全”通信系统:首先,利用基于SVD预编码的波束成形技术建立“优势信道”,经MATLAB仿真结果表明该技术在理想与非理想信道估计条件下均能有效扩大合法接收者的优势;其次,本文提出基于BCH码的安全编码方案,经MATLAB仿真结果表明该方案显著扩大窃听者的接收误码率。2.建立MIMO波束成形联合安全编码的“无条件安全”通信系统模型,讨论分析其在理想与非理想信道条件下系统的安全性能,证明信道估计误差对系统安全性能的影响以及实际系统中物理层安全传输的可实现性。基于USRP-LabVIEW平台实现多天线物理层安全传输系统的测试,其结果表明所建系统具有通信的安全性和可靠性,证明该系统可以实现无条件安全传输。3.建立人工噪声结合协作干扰的MISOSE模型,以系统安全速率作为衡量系统安全性能的指标,优化功率分配方案,使系统安全速率达到最大。4.针对非理想情况,建立三种不同场景下的MISOSE协作模型,分别计算最优功率分配下的系统安全速率。比较理想与非理想信道条件下系统安全速率最大值,分析估计误差对系统安全性能的影响,验证在有信道估计误差的实际通信环境中物理层安全传输的可实现性。经MATLAB仿真得到,非理想信道估计条件下三种MISOSE协作模型以及理想模型随发送端的功率分配比从0到1渐变时的系统安全速率值的变化曲线,找到最优功率分配方案。
[Abstract]:Physical layer security technology abandons traditional security methods based on computational complexity infeasibility and innovatively utilizes the inherent randomness and non-replicability of wireless noise channels. The security of wireless data transmission is realized by using channel noise as "key". However, most of the existing researches on physical layer secure transmission are based on the assumption that the channel state information is ideal, but the channel estimation error is inevitable in the application. In the actual wireless communication system, all of them are not ideal channel state information. The research of physical layer security transmission based on ideal channel state information lacks the adaptability to the non-ideal factors, so it is different from the real system and can not realize the target security. In order to improve the security of wireless communication, the performance of physical layer secure transmission system under the condition of non-ideal channel estimation is studied in this paper. The main research work is as follows: 1. The "unconditional secure" communication system based on MIMO eavesdropping channel model is studied. Firstly, the "dominant channel" is established by using the beamforming technology based on SVD precoding. The simulation results of MATLAB show that this technique can effectively expand the advantages of the legitimate receiver under both ideal and non-ideal channel estimation conditions. Secondly, this paper proposes a secure coding scheme based on BCH code. The simulation results of MATLAB show that the scheme can significantly increase the bit error rate (BER) of eavesdroppers. The "unconditional secure" communication system model of MIMO beamforming joint security coding is established, and the security performance of the system under ideal and non-ideal channel conditions is discussed and analyzed. The influence of channel estimation error on the security performance of the system and the realizability of the physical layer secure transmission in the real system are proved. Based on USRP-LabVIEW platform, the security transmission system of multi-antenna physical layer is tested. The results show that the system has the security and reliability of communication, and proves that the system can realize unconditional secure transmission. The MISOSE model of artificial noise combined with cooperative interference is established. The system security rate is taken as the index to evaluate the security performance of the system and the power allocation scheme is optimized to maximize the security rate of the system. In order to solve the non-ideal situation, the MISOSE cooperation model under three different scenarios is established, and the system security rate under optimal power allocation is calculated respectively. Comparing the maximum of system security rate under ideal and non-ideal channel conditions, the influence of estimation error on system security performance is analyzed, and the realizability of physical layer secure transmission in real communication environment with channel estimation error is verified. By MATLAB simulation, three kinds of misosse cooperation model and the curve of the system security rate when the power distribution ratio of the transmitter changes from 0 to 1 under the condition of non-ideal channel estimation are obtained, and the optimal power allocation scheme is found.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN918

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