Chaotic Synchronization in Digital Communication

Second IFAC Conference on Analysis and Control of Chaotic Systems (2009), 2009

In this work, a novel chaotic encryption technique is proposed to realize a secure communication system. In the proposed method, the message signal to be transmitted is first encrypted using a chaotic keystream and then masked with a chaotic signal. At the receiver end, the received chaotic signal is used for synchronization and to recover the encrypted signal. After applying the same keystream used in transmitter side, the message signal could be decrypted back. The main contribution of this work is generation of the keystream which is not part of the transmitter chaotic oscillator but is produced using an oscillator of different structure.

Seventh International Symposium on Signal Processing and Its Applications, 2003. Proceedings., 2003

In this note we propose a new chaotic modulation scheme with output feedback. It is shown that the receiver can synchronize with the transmitter with any desired rate. Moreover, this approach can be applied to a large class of chaotic systems and provides higher security against an intruder. The robustness of our scheme with respect to noise is illlistrated and compared to the symmetric chaos shift keying method.

Chaos Theory - Modeling, Simulation and Applications - Selected Papers from the 3rd Chaotic Modeling and Simulation International Conference (CHAOS2010), 2011

In this paper, a modified chaotic shift keying method is proposed to transmit digital bits securely over a communication channel. The scheme is based upon encrypting the digital bits 0 and 1 into infinite levels by applying the keystream such that there is no recognisable pattern in the encoded transmitted signal. The encoded transmitting signal generated is shown to resist popular attack method therefore realizing a secure and trustworthy digital communication system.

Applications for Encryption

In this work the authors thoroughly investigated a digital information transmission system using discrete chaotic signal over cable. As an example in their work the authors consider the non-autonomous 2 nd order non-linear oscillator system presented in Tamaševičious, Čenys, Mycolaitis, and Namajunas (1998) which is particularly suitable for digital communications and present the experimental results regarding synchronization. The effect of noise (internal or external) on the synchronization of the driveresponse system (unidirectional coupling between two identical systems) is analyzed and since in every practical implementation of a communication system, the transmitter and receiver circuits (although identical) operate under slightly different conditions the case of the mismatch between the parameters of the transmitter and the receiver is considered. Moreover, there is a study of the robustness of the system with reference to the desired security, proposing a more sophisticated approach, which combines the simplicity in the implementation of a chaotic system with an enhanced encoding scheme that will overall increase security.

This paper presents an encryption alg orithm that can be used for text messages, images and recorded voice with high security. The proposed algorithm is then applied to secure communication using a new approach for constructing two chaotically synchronized systems in the presence of a multipath Rayleigh fading channel. The results reveal that synchronization and a signal to chaos ratio of -252dB have been achieved..

In this paper a new, efficient algorithm for secure digital communications in error free networks is presented. The proposed scheme uses pseudo chaotic random number generator (PCRNG) for secure communication. A quantized version of the PCRNG is used and the number of bits used for quantization decides the bandwidth expansion factor of resulting spread sequence. The proposed scheme utilises deterministic chaotic encryption via the logistic map and requires 3 keys. The initial seed, the chaotic equation and the value of constant α. This scheme has been successfully tested for the encryption of images and audio signals.

2006 International Conference on Advanced Computing and Communications, 2006

We try to revive the first generation chaotic secure communication scheme by improving the degree of security level, using the concept of mutual chaotic synchronization. This provides additional robustness to secure communication systems designed for quality of service applications. This is aimed at obtaining a system which can generate very long streams of keys to be directly used for one-time stream ciphers (additive masking). The first generation scheme has the advantage of being easily implementable and uses less complex algorithm but have less degree of security. This proposed method is supposed to increase the degree of security level as it is protected against the parameter estimation attacks, which are a major threat to the identical synchronization schemes.

Chaos, Solitons & Fractals, 2003

In this paper we propose some secure digital communication schemes using discrete chaotic systems. In our approach a message is encrypted at the transmitter using chaotic modulation. Next, the driving signal synchronizes the receiver using discrete observer design or drive-response concept. Finally, by reverting the coding procedure the transmitted message is reconstructed. To demonstrate the efficiency of our communication schemes a modified H e enonÕs map is considered as an illustrative example.

There is a great interest in secure communications within industry and various sectors of society. It has been found that chaotic systems and cryptosystems share many similar properties. For instance, chaotic systems are sensitive to the initial conditions, which correspond to the diffusion property of good cryptosystems. In this paper we describe a technique for transmitting digital information using pseudo chaotic carrier. The pseudo chaotic sequences are used as spreading codes to encode each user's message. The user's message can again be separated by the orthogonal property of chaotic sequences at the receiver. Chaos-based communication systems offer higher security Index Terms-chaos, pseudo chaotic carrier, chaotic function, NLFS R, PCS .

Understanding Complex Systems, 2011