一种改进的混沌扩频序列研究  

Study on Modified Chaotic Spreading Spectrum Sequence

作　　者：肖利丽[1] 何世彪[1] 

机构地区：[1]重庆通信学院研究生队,重庆400035

出　　处：《现代电子技术》2010年第15期15-17,20,共4页Modern Electronics Technique

摘　　要：通过对混沌映射的研究,针对单一映射产生的扩频序列其系统复杂度低,容易通过反向逆推估计出系统初值的缺点,以Logistic映射为基础,构造出一种新的映射。该映射容易被数字电路实现,且具有较高的系统复杂度。该序列由两个不同初始值的两个Logistic映射复合而成,具有较高的安全性。在此,对复合混沌序列初值敏感性、平衡性、自相关性、功率谱密度进行了分析。研究结果表明,这种新型的序列具有较高的初值敏感性、优良的平衡性、自相关性和伪随机性,是一种有效和可靠的扩频序列。Aiming at overcoming the shortcoming that the spreading spectrum sequence（SSS） generated by single map has low complexity and that the initial value is easy to be estimated by inversion,a new map is constructed by the research on the chaotic map based on Logistic-map.This map can be realized easily by digital circuit and has high system complexity.The modified chaotic sequences are compounded by two Logistic maps with two different initial values and more secure for communication.The initial-value sensitivity,self-correlation and power spectral density of the compounded chaotic sequences are analyzed.The results indicate that the new sequences have higher sensitivity to initial conditions,better autocorrelation characters and excellent pseudo randomness.A practical scheme of spreading spectrum is simulated.The simulation results show the effectiveness and reliability of the new-style chaos sequences.

关 键 词：混沌序列 LOGISTIC映射 直接序列扩频 相关性分析 

分 类 号：TN911[电子电信—通信与信息系统]