Abstract: The article explores the technology of hybrid modeling of chaotic systems in the form of synchronization of digital and analog models of the Rossler system, interacting via analog-digital and digital-analog conversion paths. The unidirectional and bidirectional variants of chaotic synchronization are considered, and the synchronization error is estimated for each of the specified cases. For the analog implementation of the Rössler system, a circuit has been developed based on operational amplifiers, multipliers, and precision passive elements. The digital model of the system is based on a semi-implicit hardware-oriented method of numerical integration of the second order of algebraic accuracy. In order to substantiate the choice of the method, graphs of the performance of various solvers of ordinary differential equations are presented when simulating the Rössler system. It is shown that the chosen semi-implicit numerical integration method has the highest computational efficiency among all second-order methods. Experimentally demonstrated the ability to synchronize analog and digital models of a chaotic system. The synchronization of two and three models of the Rossler system in various variants of the connection topology is considered. By analyzing the synchronization error, it is shown that the greatest accuracy is achieved when using a fully coupled topology, which is based on the bi-directional synchronization method of the three models of the Rössler system.

Abstract: The most common type of sounding signals of sonar systems are broadband linear-frequency-modulated signals (LFM). Due to the use of such signals it is possible to increase the range and resolving power of hydroacoustic devices, but this does not solve the problem of mutual interference of pulses. One type of broadband signals are chaotic oscillations, which theoretically are able to become an alternative to chirp signals due to increased resistance to crosstalk. The paper compares chaotic and chirp signals by simulating their passage in an aqueous medium. Chaotic signals generated by systems with different numbers of basins of attraction are investigated. The study shows that chaotic signals are more resistant to mutual interference, and also experience less attenuation when propagating in an aqueous medium compared to the types of signals currently used. The stability of chaotic broadband signals to interference and attenuation correlates with the number of basins of attraction of the attractor of the generating chaotic system. Based on the results of the work, it can be concluded that the chaotic signals are used as probing pulses of sonar systems.