L.V. Savkin – Leading Designer, 
Special Design Bureau of Space Instrumentation of Space Research Institute of RAS (Tarusa),
Post-graduate Student, Kotel'nikov IRE of RAS (Moscow) E-mail: solaris.rafo@gmail.com

In this article the possibilities of using Thomas chaotic systems as a carrier of information are considered. At the same time, the criteria for choosing a dynamic system are observed:
1) the simplicity of the technical implementation of identical generators of chaotic oscillations at the transmitting and receiving sides; 2) spectral characteristics of the carrier chaotic signal (the shape of the envelope of the spectral power density, the frequency range, the presence of periodicity windows in the spectrum of the chaotic carrier, etc.);
3) stability of the mode of generation of chaotic oscillations on the transmitting and receiving sides; 4) time of complete synchronization or registration of a synchronous chaotic response at the receiving side; 5) complexity of the reconstruction of the attractor of the master oscillator of chaotic oscillations.
The problem of constructing systems fit hidden information transmission using the dissipative Thomas «labyrinth» chaos, which was not previously used for this kind of problems is considered.
The main attention in the work is paid to the possibility of constructing a chaotic information transmission system in which a onedimensional realization of Thomas's dissipative «labyrinth» chaos acts as a carrier of a useful information signal.
Several definitions and agreements have been introduced related to the methods of communication systems with chaotic labyrinth modulation. Possibilities of symmetrical and asymmetrical control of the Thomas slave oscillator are explained. In the Simulink software environment, based on numerical modeling, the possibility of constructing communication systems with one-parameter chaotic labyrinth modulation is shown. As the main method of controlling the Thomas oscillator, an asymmetric control of the frequency parameter was chosen by additively mixing its value with the value of the information signal. Examples of information signal extraction from an idealized channel without noise and a data transmission channel with a «carrying chaotic signal-to-noise» ratio of ~ 104 are shown.
The possibility of constructing a chaotic communication system, the dynamics of which is characterized by many unstable equilibrium points, different from the dynamics of the attractor type, is shown. The advantage of such communication systems is the complexity of the phase portrait reconstruction by analyzing time series.

Savkin L.V. The one-parametric chaotic labyrinth modulation. Electromagnetic waves and electronic systems. 2020. V. 25. № 4. P. 11−19. DOI: 10.18127/j15604128-202004-02. (in Russian)

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