作　　者： ; ;

机构地区： 杭州电子科技大学电子信息学院

出　　处： 《电路与系统学报》 2011年第6期99-103,共5页

摘　　要： 利用有限精度的数字系统产生混沌伪随机序列时会出现短周期问题。为克服这种数字混沌动力学退化从而产生性能良好的伪随机序列,提出了一个变参数变结构混沌系统。该系统含有两个开关函数,在自身变量的控制下使混沌系统的某个参数在四个值之间自动切换,同时使其在两个结构不同的子系统之间切换。系统参数的变化相当于对其进行随机扰动,系统结构的变化相当于两个混沌系统的混合,系统参数扰动和结构变化都可扩展混沌数字序列的周期,改善其统计特性。在对该系统理论分析的基础上,利用DSP实现了该混沌系统的数字序列,并对此数字序列进行了NIST测试。测试结果证明变结构、变参数混沌系统可改善其数字序列的随机性。 That chaotic system is implemented with finite precisions in digital systems leads to a short cycle problem for PR （pseudo-random） sequences. To solve the dynamics degradation of digital chaos and ：generate good PR sequence, this paper presents a chaotic system with variable parameter and construction, which contains two switching functions and automatically changes in its＇ four parameter values and two different structure of the subsystems under the control of its own variables. The former is equivalent to random perturbation to system parameters, and the later as well as to the mixing of two systems. The both changes can increase the cycle length and improve the statistical properties of chaotic digital sequences. Based on theoretical analysis for the proposed system, digital sequences of the system are implemented using DSP, and the obtained sequences are tested by NIST standard. The tested results show that the proposed chaotic sequence can improve the randomness of the digital sequences.

关 键 词： 混沌 变参数 变结构 数字序列

领　　域： [电子电信] [电子电信]