基于改进的AES算法加密跳频图案研究

发布时间：2018-03-19 17:03

本文选题：跳频图案　切入点：AES算法　出处：《南昌航空大学》2017年硕士论文　论文类型：学位论文

【摘要】：跳频通信具备良好的抗干扰、抗衰落以及多址等性能,不管是在军事通信领域还是民用通信领域都被广泛地运用。在组网通信时,跳频图案是作为跳频系统中控制跳频频率跳变的关键技术,其性能的好坏直接影响整个跳频系统的安全性。然而,在这个高频率、高速度的信息时代,随着通信干扰技术的快速发展,基于传统序列构造的跳频图案存在着间隙小、保密性低等缺点,已经不能满足高保密通信系统的要求,因此,为了改善传统序列构造出的跳频图案存在的缺陷,本文提出一种加密宽间隔跳频图案研究方案。本文首先详细介绍AES算法加密的过程,并分析算法的优缺点。为了能够克服因算法的公开性,而致使攻击者有机可趁,针对AES算法加密过程中唯一的非线性部件S盒,在研究混沌映射的基础上,提出了一种重构方法,从而达到改进AES算法。其重构方法是:利用混沌Henon映射的遍历性、对初始条件的敏感性等特点并将其映射空间[0,1]均匀划分为256个子区间作为存储S盒数值,同时通过所设定的适应度函数优化S盒的性能排序,使得重构后S盒中的元素按性能强弱排序。其次,在分析几种传统构造跳频图案方法的后,选取了性能好、数目多且易于实现的RS码序列作为设计跳频图案的基础并详细阐述了其原理,同时为了避免跳频图案相邻频点间间隔过小,而引起多进衰落,通过一种新的宽间隔处理法对其进行优化。最后利用改进的AES算法实现对传统的RS码序列加密,同时通过新宽间隔法改善其相邻频点间间隔,从而构造出保密性强的宽间隔跳频图案。研究表明,改进的AES算法加密RS码宽间隔跳频图案,不仅使传统的RS码跳频图案具有一定强度的密码特性,而且在相同条件下,改进AES算法加密的RS码宽间隔跳频图案相邻频点间间隔明显优于传统的跳频图案,并且优于非重复宽间隔处理后的跳频图案。
[Abstract]:Frequency-hopping communication has good performance of anti-jamming, anti-fading and multi-access. It is widely used in both military and civil communication fields. Frequency hopping pattern is the key technology to control the frequency hopping in frequency hopping system. Its performance directly affects the safety of the whole frequency hopping system. However, in this information age of high frequency and high speed, With the rapid development of communication interference technology, the frequency hopping pattern based on traditional sequence has some shortcomings, such as small gap, low confidentiality and so on, so it can not meet the requirements of high security communication system. In order to improve the defect of frequency hopping pattern constructed by traditional sequence, this paper proposes a scheme to encrypt wide-interval frequency-hopping pattern. Firstly, this paper introduces the encryption process of AES algorithm in detail. The advantages and disadvantages of the algorithm are analyzed. In order to overcome the openness of the algorithm, the attacker can take advantage of it, aiming at the S-box, the only nonlinear part in the encryption process of the AES algorithm, based on the study of chaotic mapping. In this paper, a reconstruction method is proposed to improve the AES algorithm, which is based on the ergodicity of chaotic Henon maps. The sensitivity of the initial condition and the mapping space [0 / 1] are divided into 256 sub-regions to store S-box values, and the set fitness function is used to optimize the performance ranking of S-boxes. The elements in the reconstructed S-box are sorted according to the performance. Secondly, after analyzing several traditional methods of constructing the frequency-hopping pattern, the performance of the reconstructed S-box is very good. A large number of RS code sequences, which are easy to be implemented, are used as the basis for the design of frequency-hopping patterns and the principle is expounded in detail. In order to avoid the excessive spacing between adjacent frequency points of the frequency-hopping patterns, multi-path fading is caused. At last, the improved AES algorithm is used to encrypt the traditional RS code sequence, and the new wide interval method is used to improve the interval between adjacent frequency points. The research shows that the improved AES algorithm not only makes the traditional RS code frequency hopping pattern have some strong cryptographic characteristics, but also under the same conditions, the improved AES algorithm can encrypt the RS code wide interval frequency hopping pattern. The frequency hopping pattern encrypted by the improved AES algorithm is obviously superior to the traditional frequency hopping pattern and is superior to the frequency hopping pattern after non-repetition wide interval processing.
【学位授予单位】：南昌航空大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN914.41;TN918

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