-Chaotic system are unstable and a-periodic ,making them naturally difficult to identify and to predict .This nonlinear , unstable and a-periodic characteristics of chaotic signals has numerous features that make it attractive for communication use. This field of communication is termed as chaotic communication. Chaotic communication signals have large bandwidth and have low power spectrum dens...

Protecting signals is one of the main tasks in information transmission. A large number of different methods have been employed since many centuries ago. Most of them have been based on the use of certain signal added to the original one. When the composed signal is received, if the added signal is known, the initial information may be obtained. The main problem is the type of masking signal em...

This paper introduces multifractal theory into the research of chaotic channels, and a novel model of chaotic channel is established from nonlinear science standpoint. By studying the relationship between multifractal dimensions and work environments, increments probability distribution, and statistical self-similarity of low power line communication (L-PLC) channel which is a typical chaotic c...

The problem of separation of a noise-contaminated observed sum of chaotic signals into the individual components is considered. A noise threshold is found above which high-quality separation is impossible. Below the threshold, each signal is recovered with any prescribed accuracy with a separation method. The threshold effect is shown to be associated with the information content of chaotic sig...

When the number of the mixed signals is less than that of the source signals, the underdetermined blind source separation (BSS) is a significant difficult problem. Due to the fact that the great amount data of speech communications and real-time communication has been required, we utilize the intractability of the underdetermined BSS problem to present a dual key speech encryption method. The o...

Using chaotic signals in spread-spectrum communications has a few clear advantages over traditional approaches. Chaotic signals are nonperiodic, wide-band, and more difficult to predict, reconstruct, and characterize than periodic carriers. These properties of chaotic signals make it more difficult to intercept and decode the information modulated upon them. However, many suggested chaos-based ...

Chaotic signals are used in digital communications primarily in a bid to increase the security of transmissions. Moreover, second-order cyclostationary characteristics can easily be identified in chaotic signals used in communication systems. The detection of the cyclostationary properties in the transmitted signal decreases the security level for such systems. In this paper, we focus our atten...