Adaptive coupled synchronization among three coupled chaos systems and its application to secure communications

Abstract

In this paper, the adaptive synchronization method of three coupled identical chaos systems is proposed. New generic criteria of global chaos synchronization and strict theoretical proofs are given. The unidirectional (bidirectional) coupled system will synchronize by adding three adaptive feedback gain equations. As an example, the three Rössler chaotic systems with unidirectional coupling are given to realize the adaptive coupled synchronization; at the same time, the three Lorenz chaotic systems donate the bidirectional coupling adaptive synchronization. This paper also extends the above adaptive synchronization method to secure chaos communications through the method of chaos masking. Based on the three coupled identical Lorenz chaotic systems, a novel method of chaos encryption is proposed, and the basic idea is that after encrypting two times in two transmitters and one receiver, information signal can be recovered exactly at the receiver end. In consideration of interfering random white noise, the results of encoding and decoding are simulated and analyzed for the multistage chaos synchronized system. By analyzing the characteristics of noise, this paper presents a de-noising method using wavelet transform. At last, a secure communications method for high amplitude information signal transmission based on chaotic masking is studied. With the MATLAB, the effects of signal de-noising could be demonstrated.

Time-Delay Characteristics of Complex Lü System and Its Application in Speech Communication

“…Compared with other examples of communication systems [34][35][36][37][38][39][40], the proposed secure communication scheme based on the time-delay complex Lü system has the following advantages:…”

“…Compared with other examples of communication systems [ 34 , 35 , 36 , 37 , 38 , 39 , 40 ], the proposed secure communication scheme based on the time-delay complex Lü system has the following advantages: Due to the time lag in the transmission process, the synchronization phenomenon between the transmitter and the receiver is closer to the real situation; The STDS controller based on Lyapunov’s stability design is relatively simple and has strong stability. Equipped with double time-delay, the complex Lü system is safer; Encryption is performed using linear equations of state variables, which is quite different from previous encryption methods.…”

Time Delay Complex Chen Chaotic System and Secure Communication Scheme for Wireless Body Area Networks

“…Compared with other examples of communication systems [ 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ], the CMPS-based communication scheme has the following advantages:…”

Algoritmo de Encriptación de Imágenes Utilizando el Atractor Caótico de Lorenz

“…Para las cuatro imágenes presentadas se hallaron los coeficientes de correlación agrupados en la Tabla II, las medidas que evalúan la resistencia a ataques diferenciales UACI (promedio unificado de intensidad de cambio, sus siglas en inglés) y NPCR (razón de cambio de pixeles, sus siglas en inglés), además de la entropía correspondiente, los cuales se presentan en las tablas III y IV. La expresión matemática para UACI está dada por la ecuación (9).…”