TDCS改进型反馈控制混沌基函数生成方法  

TDCS Modified Feedback Control Chaotic Basis Function Generation Method

作　　者：宋耀辉 黄仰超[1] 高维廷[1] 胡航 张衡阳[1] SONG Yaohui;HUANG Yangchao;GAO Weiting;HU Hang;ZHANG Hengyang(Information and Navigation College,Air Force Engineering University,Xi’an,Shaanxi 710077,China)

机构地区：[1]空军工程大学信息与导航学院,陕西西安710077

出　　处：《信号处理》2021年第1期104-110,共7页Journal of Signal Processing

基　　金：国家自然科学基金(61701521,61901509);陕西省自然科学基金(2018JQ6074)。

摘　　要：针对混沌基函数在数字化生成时出现混沌退化现象,导致变换域通信系统隐蔽性和安全性下降的问题,提出一种反馈控制混沌基函数的生成方法。该方法主要基于改进型反馈控制混沌序列,并据此产生伪随机相位;在Lyapunov指数严格为正的反馈控制混沌系统基础上,分析得出该系统数字化时所需的最小运算精度;同时,引入调整因子,使得数字混沌系统与原始混沌系统特性保持一致。理论分析和仿真实验表明,该方法能产生大量伪随机性强、复杂度高的混沌基函数,在基函数延时自相关、相位覆盖率和近似熵等多个方面具有良好的综合性能。Chaotic degradation occurs when the chaotic basis function is generated digitally in transform domain communication system,which leads to the decrease of the concealment and security of communication.In response to the above problems,a feedback control method for generating chaotic basis functions is proposed.This method is mainly based on the improved feedback control chaotic sequence and generates pseudo-random phase accordingly.Firstly,on the basis of the feedback control chaotic system with Lyapunov index being strictly positive,the minimum operation accuracy required for digitization of the system is obtained.Secondly,the adjustment factor is introduced to make the digital chaotic system consistent with the original chaotic system.Theoretical analysis and simulation experiments show that this method can produce a large number of chaotic basis functions with strong pseudo-randomness and high complexity,and has good comprehensive performance in such aspects as the delay autocorrelation,phase coverage and approximate entropy of the basis functions.

关 键 词：变换域通信系统 基函数 反馈控制 混沌 

分 类 号：TN911.7[电子电信—通信与信息系统]