【作者】 刘光友；

【导师】 李智；

【作者基本信息】 西安电子科技大学 ， 控制理论与控制工程， 2008， 硕士

【摘要】 混沌信号具有不规则,非周期,似噪声,不相关,宽频带,对初始条件极为敏感的特点,适合应用于保密通信。混沌参数调制把信号谱的整个范围都用来隐藏信息,保密性强,目前基于时变参数的混沌调制与解调方案不是很多,实际的混沌通信电路更少。本文在混沌同步的基础上设计合适的调制解调方法,恢复隐藏于混沌参数中的信息信号。所做的工作主要是:根据混沌同步对参数的敏感性,设计基于混沌同步与异步的调制与解调数字通信方案;利用一个低通滤波器,提出混沌自同步的调制解调方法;构造基于自适应控制的同步控制器和参数估计函数,使接收系统参数能对发送系统参数的所有状态同步跟踪,估计出发送系统的参数,恢复信息。分析了单参数与多参数调制的情况。通过数值仿真验证了方案的有效性。设计了一种单参数调制的保密通信电路,并通过电路仿真,验证该通信方案的可行性。更多还原

【Abstract】 Chaotic signals are irregular, aperiodic, noise-like, uncorrelated, broad frequency spectrum, very sensitive to initial conditions. These properties mentioned above make chaos apply in secure communication particularly. Chaos parameter modulation communication has satisfactory confidentiality with the entire range of frequency spectrum to conceal message. At present, there are few schemes of chaotic modulation and demodulation based on time-varying parameter, and much less on practical circuit communication system.In this paper, the contents of the study are mainly focused on designing appropriate modulation and demodulation methods to restore the message signal concealed in the chaos signals based on chaos synchronization. The main contributions are as follows: With chaos synchronization very sensitive to parameters, a digital communication method is proposed by designing a demodulating method to restore information signal. With a nonlinear low-pass filter, a method of modulation and demodulation is discussed in self-synchronizing chaotic communication systems. Based on adaptive control method, a controller is designed to control receiver and transmitter chaotic systems to synchronize, and design appropriate parameter estimation function so that states of parameters in receiver can synchronously track to all states of the parameters in transmitter. By estimating the parameters in receiver, information signals are demodulated. In this paper, Single parameter modulation and multi-parameter modulation for secure communication are discussed. All the methods are proved to be effective by numerical simulations. Then, a secure communication circuit is designed. Through a circuit simulation, the feasibility of the communication scheme is verified.更多还原