Description: Studying the state of nonlinear dynamic systems that demonstrate complex conduct is a topical issue in radio engineering and telecommunications. One of the reasons for interest in this problem is the possibility of practical use of research results for reserved information transmission. During the development of modern systems for the confidential information transmission, developers are increasingly turning to the use of alternative methods to ensure the secrecy of signals dealing with chaotic dynamics. There is a tendency to use signals which characteristics are close to flat random noise. These signals include chaotic sequences. Possessing signs of chance, the simplest mathematical models of chaotic sequences have a structured phase portrait that distinguishes them from ordinary flat random noises. Therefore, the direct use of chaotic sequences for the information transmission does not solve the problem of information transmission systems secrecy. At present, the methods of phase portraits complication and the restoration of chaotic signals that are dealing with them, as well as the evaluation of their secrecy in condi-tions of the prior uncertainty regarding the kind of chaotic signal and noise statistics are insufficiently studied. The study of the nonlinear dynamic systems conduct demonstrate complex conduct can partially solve the problem of developing methods for complicating the phase portrait of chaotic signals, which helps to increase the secrecy and their processing in the presence of flat random noise. The reason for the interest in this problem is also related to the possibility of practical use of research results for latent information transmission. Therefore, the issue remains an actual problem. In the work, the authors suggested to increase the secrecy of information transmission systems by using chaotic processes. A phase-manipulated signal is inserted in a chaotic carrier that destroys the typical for chaotic processes conduct based on phase plane, that does not show features of structuring. As a chaotic sequence, the chaotic sequence of Chebyshev is used. The authors propose a functional diagram of the system for transmitting information using chaotic signals as an option for the research results practical use.
Keywords: IID-secrecy, chaotic sequences, attractor, Chebyshev polynomial, phase portrait, MPSK signal
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