In this paper, we propose a pseudo-chaotic modulation suitable for ultrawide-bandwidth impulse-radio communication systems. The coding scheme is based upon controlling the symbolic dynamics of a chaotic map for encoding the digital information to be transmitted. The pseudo-chaotic time hopping enhances the spread-spectrum characteristics of the system, by removing most periodic components from ...

Spatiotemporal chaos of a two-dimensional one-way coupled map lattice is used for chaotic cryptography. The chaotic outputs of many space units are used for encryption simultaneously. This system shows satisfactory cryptographic properties of high security; fast encryption (decryption) speed; and robustness against noise disturbances in communication channel. The overall features of this spatio...

In this paper the problem of simultaneous reconstruction of the state, the sensor fault and the uncertainty in linear systems is considered. Inspired by the idea in chaotic masking, one scheme for chaotic secure communication, this paper proposes a new scheme to resolve the above problem. Together with iterative learning strategy, the generalized state observer proposed in chaotic masking can b...

The passage of light or of electrons through a disordered medium is modified in the presence of resonances. We describe a simple model for this problem, and present first results.

This paper investigates the problem of output regulation of Rössler prototype-4 system, which is one of the classical chaotic systems proposed by O.E. Rössler (1979). Explicitly, for the constant tracking problem, new state feedback control laws regulating the output of the Rössler prototype-4 chaotic system have been derived using the regulator equations of C.I. Byrnes and A. Isidori (1990). T...

Recently, a chaotic image encryption algorithm based on information entropy (IEAIE) was proposed. This paper scrutinizes security properties of the algorithm and evaluates validity of the used quantifiable security metrics. Some common insecurity problems in the field of chaotic image encryption are found in IEAIE, e.g. the short orbits of digital chaotic system and invalid sensitivity mechanis...

Aiming at the abrupt faults of the chaotic system, an adaptive observer is proposed to trace the states of the master system. The sufficient conditions for synchronization of such chaotic systems are also derived. Then the feasibility and effectiveness of the proposed method are illustrated via numerical simulations of chaotic Chen system. Finally, the proposed synchronization schemes are appli...

Chaotic synchronization is the key technology of secure communication. In this paper, an impulsive control method for chaotic synchronization of two coupled Lorenz chaotic system was proposed. The global asymptotic synchronization of two Lorenz systems was realized by using the linear error feedback of the state variables of the drive system and the response system as impulsive control signal. ...

Encryption and Decryption is mainly used to transfer the data between the two communication channels. This paper explains the normal approach of the encryption as well as decryption by using chaotic algorithm and also tried to implement this in video frames. Here the basic chaotic encryption algorithm used to encrypt the images by using the three dynamic chaotic systems (Lu or Chen or Lorenz) t...

The real issues of communicating over radio channels with continuous time chaotic signals are addressed. Synchronized and nonsynchronized methods are assessed. The modeling of radio channels (including multipath and Doppler) is reviewed, and then the effect on chaotic signals is investigated. The bandwidth efficiency of chaotic communication systems is discussed, and compared to conventional me...