Chaotic signals produced by nonlinear systems can be used for encrypting the transmitting messages in secure communications. Synchronization of chaotic systems has an important role in this field of science. Figure 1 shows how chaotic signals and chaos synchronization are utilized for secure communication. The message is a signal that should be transferred in a secure encrypted form. Using two ...

In this paper, the wavelength mismatch between the message and the chaotic carrier in the chaotic optical communication with chaos-masking has been experimentally investigated. The results show that the decryption performance of the receiver can be improved when the message wavelength is greater than that of the chaotic carrier. When the wavelength offset is set to 0.12 nm, high-speed secure op...

Chaotic signals have been considered potentially attractive in many signal processing applications ranging from wideband communication systems to cryptography and watermarking. Besides, some devices as nonlinear adaptive filters and phase-locked loops can present chaotic behavior. In this paper, we derive analytical expressions for the autocorrelation sequence, power spectral density and essent...

Recent investigations show that wireless communication systems are a very promising application area of chaotic dynamics. At the same time synthesis of chaotic oscillators suitable for IC implementation and producing chaotic oscillations in the specified frequency band is a problem. Here the problem of synthesis of RC chaotic oscillator with preassigned spectrum is discussed. Spectral propertie...

Recent work has considered the possibility of utilizing symbolic representations of controlled chaotic orbits for digital communication. We argue that dynamically a coding scheme usually leads to trajectories that live on a nonattracting but noise-resisting chaotic saddle embedded in the chaotic attractor. We present analyses and numerical computation which indicate that the channel capacity of...

Chaos based communications have drawn increasing attention over the past years. Chaotic signals are derived from non-linear dynamic systems. They are aperiodic, broadband and deterministic signals that appear random in the time domain. Because of these properties, chaotic signals have been proposed to generate spreading sequences for wide-band secure communication recently. Like conventional DS...

Application of chaos in communications, in particular, wireless communications is actively investigated since 1990s [1–5]. Direct chaotic scheme of wireless communications employs chaotic radio pulses as information carriers. This scheme was proposed in 2000 [6–7]. At that time the first experiments were made with this scheme in 900–1000 MHz range. In 2001 investigation of UWB direct chaotic sy...

Chaotic communications based on semiconductor lasers have aroused great research interest since 1990s. Physical-layer encryption using chaotic lasers is an alternative to transmit message rapidly and confidentially. There are some practical devices and setups for optical chaotic communications, which are intuitively considered to be secure. However, there is lack of a set of security evaluation...

The experimental study of a secure chaotic synchronized communication system is presented. The synchronization between two digital chaotic oscillators, serving as a transmitter-receiver scheme, is studied. The oscillators exhibit rich chaotic behavior and are unidirectionally coupled, forming a master-slave topology. Both the input information signal and the transmitted chaotic signal are digit...

We derive the Cramér-Rao lower bound associated with the estimation of the initial condition of noise-embedded chaotic signals produced by general onedimensional maps. We relate its asymptotic behaviour to the chaotic attractor’s Lyapunov number. These results can be used to choose the chaotic generator more suitable for applications on chaotic digital communication systems.