Digital chaotic sequence generator based on coupled chaotic systems

• Published in: Chinese physics B Vol. 18; no. 12; pp. 5219 - 5227
• Main Author: 刘树波 孙婧 徐正全 刘金硕
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.12.2009
• Subjects: Algorithms; Chaos theory; Coding; Computation; Computer simulation; Control systems; Cryptography; Degradation; Digital; Dynamical systems; Dynamics; Encryption; Field programmable gate arrays; Generators; Joining; Logistics; Mathematical analysis; Mathematical models; Orbits; Perturbation methods; Real time; Security; 序列发生器; 数字混沌; 混沌序列; 物流系统; 现场可编程门阵列; 耦合混沌系统; 输出速度
• ISSN: 1674-1056; 2058-3834
• DOI: 10.1088/1674-1056/18/12/019

Chaotic systems perform well as a new rich source of cryptography and pseudo-random coding. Unfortunately their digital dynamical properties would degrade due to the finite computing precision. Proposed in this paper is a modified digital chaotic sequence generator based on chaotic logistic systems with a coupling structure where one chaotic subsystem generates perturbation signals to disturb the control parameter of the other one. The numerical simulations show that the length of chaotic orbits, the output distribution of chaotic system, and the security of chaotic sequences have been greatly improved. Moreover the chaotic sequence period can be extended at least by one order of magnitude longer than that of the uncoupled logistic system and the difficulty in decrypting increases 2^128＊2^128 times indicating that the dynamical degradation of digital chaos is effectively improved. A field programmable gate array （FPGA） implementation of an algorithm is given and the corresponding experiment shows that the output speed of the generated chaotic sequences can reach 571.4 Mbps indicating that the designed generator can he applied to the real-time video image encryption.