基于级联混沌系统的分数域语音加密算法  

Audio encryption algorithm in fractional domain based on cascaded chaotic system

作　　者：徐丽云 闫涛 钱宇华 XU Liyun;YAN Tao;QIAN Yuhua(Institute of Big Data Science and Industry,Shanxi University,Taiyuan Shanxi 030006,China;School of Computer and Information Technology,Shanxi University,Taiyuan Shanxi 030006,China)

机构地区：[1]山西大学大数据科学与产业研究院,太原030006 [2]山西大学计算机与信息技术学院,太原030006

出　　处：《计算机应用》2021年第9期2623-2630,共8页journal of Computer Applications

基　　金：国家自然科学基金资助项目(61901248,62006146);山西省高等学校科技创新项目(2019L0029)。

摘　　要：为保证语音信号在通信传输中的安全性,提出一种基于级联混沌系统的分数域语音加密算法。首先,对语音信号进行分组;其次,利用混沌系统获取分数傅里叶变换的阶次,各组数据对应的阶次呈动态变化;然后,采用具有较低计算复杂度的采样型分数傅里叶离散变换得到各组对应的分数域谱数据;最后,利用级联混沌系统依次对各组分数域进行数据加密,从而实现语音信号的整体加密。实验结果表明,所提算法对密钥具有极大的敏感度,得到的加密信号与原信号相比波形和分数域谱分布更均匀、相关性更小;同时与频域加密和固定阶次的分数域加密方法相比,该算法能有效增大密钥空间,同时降低计算复杂度。可见所提算法能够有效满足语音信号的实时安全传输要求。In order to ensure the security of audio signals in communication transmission,a fractional domain audio encryption algorithm based on cascaded chaotic system was proposed.Firstly,the audio signal was grouped.Secondly,the chaotic system was used to obtain the orders of fractional Fourier transform,and the order corresponding to each group data changed dynamically.Thirdly,the sampling fractional Fourier discrete transform with less computational complexity was used to obtain the fractional domain spectrum data of each group.Finally,the cascaded chaotic system was used to perform data encryption to the fractional domain of each group in turn,so as to realize the overall encryption of the audio signals.Experimental results show that the proposed algorithm is extremely sensitive to the key,and has the waveform and fractional domain spectrum of obtained encrypted signal more uniformly distributed and less correlated compared with those of the original signal.At the same time,compared with the frequency domain encryption and fixed-order fractional domain encryption methods,the proposed algorithm can effectively increase the key space while reducing the computational complexity.It can be seen that the proposed algorithm can satisfy the real-time and secure transmission requirements of audio signals effectively.

关 键 词：通信安全 语音加密 级联混沌 分数傅里叶变换 变换域加密 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]