带有数据丢失的混沌保密通信系统采样同步控制研究

发布时间：2018-11-28 18:49

【摘要】：混沌系统是一类极其复杂的非线性系统,混沌信号具有天然的隐蔽性、初值极度敏感性、不可预测性、类似噪声等特点,从而使其非常适合应用于保密通信系统中。近些年,随着数字计算机技术的高速发展,采样控制问题引起了广泛的关注。然而,在实际的采样控制系统中常常存在着控制器数据丢失及采样周期随机不确定等现象,这将会严重地影响系统的性能甚至破坏系统的稳定性。因此,本文主要针对混沌保密通信系统采样数据丢失及随机采样周期的同步控制问题进行研究。论文的主要研究内容如下：首先,在多个随机采样周期下,针对带有控制数据丢失的驱动-响应混沌系统的同步控制问题,采取保持输入策略,将数据丢失转化为系统的输入时延,并采用输入时滞法将误差系统转化为时滞系统进行稳定性分析。控制器增益可用线性矩阵不等式(LM[)的方法求解。通过数值仿真验证控制器设计的有效性,且验证了同步系统能够很好地应用到混沌保密通信系统中。其次,针对带有控制器数据丢失的随机采样混沌同步控制问题,采取零输入策略,利用切换系统法和输入时滞法将带有数据丢失的采样系统描述为一类具有稳定子系统和不稳定子系统的切换时滞系统,并基于平均驻留时间法对其进行指数稳定性分析。同时,讨论了系统性能与数据丢失率之间的关系,由数值仿真可以得出：当数据丢失率越小时,两个混沌系统达到同步的时间越短。同时,仿真结果验证了所设计的同步控制方法能够很好地应用到混沌保密通信系统中。再次,针对带有数据丢失的有向复杂网络同步控制问题,采取保持输入策略,对全部节点设计采样反馈同步控制器,得到了使复杂网络同步的充分条件。数值仿真以含有10个Lorenz节点的有向复杂网络为例,针对所有节点不存在控制器数据丢包、部分节点控制器同时丢包、控制器不同时丢包的情况进行仿真验证,仿真结果表明所设计控制器均可使系统达到稳定,即验证了所设计控制器的有效性。同样,验证了基于混沌掩盖技术可以很好地掩盖和恢复出有用信号。最后对本文的研究工作做了总结,并提出了有待进一步研究的方向。
[Abstract]:Chaotic system is a kind of extremely complex nonlinear system. Chaotic signal has the characteristics of natural concealment, extreme sensitivity of initial value, unpredictability, similar noise and so on, so it is very suitable for application in secure communication system. In recent years, with the rapid development of digital computer technology, sampling control has attracted wide attention. However, in the actual sampling control system, there are often some phenomena such as data loss of controller and random uncertainty of sampling period, which will seriously affect the performance of the system and even destroy the stability of the system. Therefore, this paper focuses on the loss of sampling data and synchronization control of random sampling periods in chaotic secure communication systems. The main contents of this paper are as follows: firstly, under multiple random sampling periods, the strategy of maintaining input is adopted to solve the synchronization control problem of drive-response chaotic system with control data loss. The data loss is transformed into the input delay of the system, and the error system is transformed into the time-delay system by the input-time-delay method to analyze the stability of the system. The controller gain can be solved by linear matrix inequality (LM [) method. The effectiveness of the controller design is verified by numerical simulation and it is verified that the synchronization system can be well applied to the chaotic secure communication system. Secondly, the zero input strategy is adopted to solve the synchronization problem of random sampling chaos with data loss of controller. The switched system with data loss is described as a class of switched delay systems with stable and unstable subsystems by means of the switched system method and the input delay method. The exponential stability of the system is analyzed based on the mean resident time method. At the same time, the relationship between the system performance and the data loss rate is discussed. From the numerical simulation, it can be concluded that the lower the data loss rate, the shorter the synchronization time between the two chaotic systems. At the same time, the simulation results show that the proposed synchronization control method can be well applied to chaotic secure communication systems. Thirdly, aiming at the synchronization control problem of the directed complex network with data loss, the strategy of maintaining input is adopted, and the sampling feedback synchronization controller is designed for all nodes, and the sufficient conditions for the synchronization of the complex network are obtained. Taking the directed complex network with 10 Lorenz nodes as an example, the numerical simulation verifies that there is no controller data packet loss in all nodes, some node controllers lose packets at the same time, and the controller does not lose packets at the same time. The simulation results show that the designed controller can make the system stable, that is, the effectiveness of the designed controller is verified. Similarly, it is verified that the chaotic masking technique can cover up and restore useful signals well. Finally, the research work of this paper is summarized, and the direction of further research is put forward.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN918;O415.5

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