该文提出了一种新的基于第二代电流传输器(CCII)的网格多涡卷混沌吸引子产生器,用于物理混沌加密和高级加密标准(AES)加密的混合图像加密算法.因CCII比普通运放有更好的频率特性和更大的动态范围,能产生频率更高,动力学特性更复杂的多涡卷物理混沌信号.基于CCII的多涡卷物理混沌加密和AES加密的混合加密系统。不存在确定的明文密文映射关系,密文统计特性也应优于其他加密系统.基于该算法研究了混合加密和单级加密的抗统计分析能力,以及涡卷数目不同的混沌信号在该算法中应用时密文统计特性的不同.完成了基于CCII的混沌电路设计与硬件实现,对加密系统进行了数值仿真,仿真结果与理论分析一致,同时表明涡卷数目越多的混沌系统其加密产生的密文相关性越弱.
In this paper we propose a novel grid-scroll chaotic attractor generator based on the second generation current conveyor(CCII), which is used for hybrid image encryption of physical chaos encryption and advanced encryption standard (AES) encryption algorithm, because CCII has a higher speed and larger dynamic range than ordinary operational amplifier and can generate multiscroll physical chaotic signal with higher frequency and more complex dynamics properties. The hybrid encryption system of multiscroll physical chaos encryption and AES encryption based on the CCII, does not assure the relationship between plaintext and ciphertext, and the statistical characteristics of ciphertexts in this algorithm should be better than those of any other encryption system. The difference in statistical property of cipher text between the two cases is studied. One case is that the ciphertexts come from different schemes, i. e. the hybrid and the single stage ones, respectively, and the other is that the ciphertexts are generated by chaotic signals with different numbers of scrolls in the same algorithm. We design and implement the chaos circuit based on CCII, and simulat the encryption system. The results shown that they are in agreement with the theoretical analyses, and that the bigger number of scrolls chaotic system causes the weaker correlation of ciphertexts.