一种基于符号动力学的伪随机序列发生器设计方法

混沌序列具有带宽大、类噪声、难于预测和重构等特点,因而常使用于网络通信和数据加密。本文提出一种基于符号动力学和混沌系统的伪随机序列发生器的设计方法。为了克服计算机有限精度造成的短周期,对生成的混沌序列进行了周期性修正,这样不仅增大了序列的周期,而且使得序列的周期可度量。我们用两个混沌系统产生的符号序列进行异或运算后作为最终输出,从而进一步增加了输出序列的随机性,也使得输出序列更加难以破译。理论研究和模拟结果表明,该序列发生器具有较好的随机性并且便于软硬件的实现。

A Design Method of Pseudo-Random Sequences Generator Based on Symbolic Dynamics

As we all know,chaotic sequence possess good features such as broad band,noise-like,accurate regenera- tion and difficult prediction,so it is suitable for information encryption. In this paper,Pseudo-Random Sequences Gen- erator based on Symbolic Dynamics and chaotic system is presented. In order to overcome short period resulted from the finite precision in practical application,we amend the output of chaotic sequence periodically so as to lengthen the period of the sequence and make the period of the sequence can be measured. Moreover,the bit sequence generated by the XOR operation of two chaotic sequence is used as the final output sequence,by this method,the randomness of the output sequence will be increased thus difficult to decrypt. The computer simulation results also show that this Pseu- do-Random Sequences Generator has good randomness properties and can be driplemented easily in both software and hardware.