# S. O. StarkovRussian Academy of Sciences | RAS · Institute of Radioengineering & Electronic

S. O. Starkov

Doctor of science

## About

58

Publications

4,588

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631

Citations

## Publications

Publications (58)

Reactors with heavy water coolants and moderators have been used extensively in today's power industry. Monitoring of the moderator condition plays an important role in ensuring normal operation of a power plant. A cellular neural network, the architecture of which has been adapted for hardware implementation, is proposed for use in a system for pr...

This study investigated the method of semantic image analysis by using a set of neuron-like detectors of foreground objects. This method is intended to find different types of foreground objects and to determine properties of these objects. As a result of semantic analysis the semantic descriptor of the image is created. The descriptor is a set of...

Detection of moving objects in a video stream received from a moving camera is difficult computer vision task, because the motion of the camera blends with the motion of the objects in the scene. In order to tackle this problem, we propose a method based on optical flow calculation and Delaunay triangulation. Given a sequence of frames, firstly, we...

We consider in this paper a problem of the design of deterministic chaos generators with given spectral properties. It is shown that implementation of such generators is possible in the class of ring self-oscillating systems. Examples of the synthesis of systems with different types of spectrum are exhibited. The question of practical implementatio...

In this work the authors present a thorough experimental study of a practical realization of a complex
analog signal transmission system using dynamic chaos. It is demonstrated that the chaotic synchronous
response could be used as a basis for the design of secure communication channels. The results presented
in this work confirm the possibility of...

The problem of indoor multipath propagation of ultrawideband signals is considered for direct chaotic communications systems.
The values of the guard interval between the information symbols, which provides the quality of reception at a level of P
err ∼ 10−3 to 10−5, are estimated theoretically. The estimation procedure is based on the models of th...

The models of indoor multipath propagation of wideband and ultrawideband (UWB) signals are considered. Application of these
models is recommended by an IEEE working group. In the framework of one of the models corresponding to the line-of-sight conditions,
the algorithms for reception of UWB chaotic signals in the presence of reflection from multip...

Basic ideas and concepts underlying the technology of ultrawideband wireless direct-chaos communications are presented. The
factors of crucial importance for the development of this communications platform are considered. The models for the origin
of chaos in different frequency bands are discussed. Effects of multipath propagation on ultrawideband...

Possible methods for receiving ultra wideband chaotic signals are considered in case of multipath indoor propagation (line-of-sight channel model). The quality of receiving is estimated taking into account the total influence of the multitude of delayed beams as virtual noise. It is shown that the proposed approaches treated in the BER ∼10<sup>-3</...

The concept of ultra wide band (UWB) direct chaotic communication (DCC) is proposed. Main features, and the performances of proposed scheme are discussed. Theoretical aspects and some performances of proposed technology are considered. The experimental models of the system are described and some experimental results, demonstrating the wireless tran...

Phase synchronization of a receiver to consecutive data batches either with or without an ultrawide-band chaotic pulse at the beginning is considered in application to the problem of indoor communication. The probability that a received and a reference sequence are synchronized with an accuracy to one sampling interval Af is estimated without using...

Error probability estimates are obtained for a model of direct chaotic transmission of a binary information sequence in a multipath channel. Estimation is performed using digital simulation methods for various signal and multipath-channel parameters.

We consider high rate wireless communication scheme, based on wideband chaotic carrier, generated directly in microwave frequency band. Main features and the performances of proposed scheme are discussed. The experimental model of the system is designed and series of the experiments, demonstrating the wireless transmission with the data rates up to...

This paper estimates BER for Ultrawideband Direct Chaotic Communications (UWDCC) through multipath indoor channel is obtained.

We discuss a concept of Direct Chaotic Communications (DCC) that is based on the following ideas: (1) chaotic oscillator generates signals directly in a specified microwave band; (2) information component is put in the chaotic signal by means of formation of an appropriate stream of chaotic radio pulses; (3) envelope detection is used. The principl...

A method of wireless, high-rate, direct chaotic transmission of digital data is proposed. The method is based on the use of
ultrawideband chaotic oscillations generated directly in the microwave range. Experimental results are presented to demonstrate
the possibility of data transmission at a rate of up to 200 Mb/s.

The report is devoted to design of wideband chaotic oscillators and microwave implementations. A model of a basic chaotic oscillator is considered. Results of both simulation and experiments are demonstrated. Examples of chaotic modes in different frequency bands and with spectrum bandwidths up to 30% with respect to the central frequency are given...

We discuss the concept of Direct Chaotic Communication (DCC). The scheme is based on the following ideas: (1) the chaotic source generates chaotic oscillations directly in the specified microwave band; (2) information component is input by means of formation of the appropriate stream of chaotic radio pulses; (3) envelope detection is used. The prin...

A scheme of chaotic-carrier data communications at radio or microwave frequencies is suggested. The main idea is that a chaotic oscillator should operate in the communication band. The scheme is implemented in an experimental model. High-speed data transmission is effected by means of a radically new carrier, namely, deterministic chaos generated a...

An approach to design of chaotic oscillators with preassigned spectral characteristics is proposed and its practical realization is demonstrated. The basic idea of the approach is to form a frequency-selective circuit and to connect it to a harmonic oscillator so as to provide generation of chaotic oscillations with given spectral characteristics.

A method to identify entities by means of tags is suggested. The tags are represented by sets of unstable periodic orbits
that form the framework of a chaotic attractor. The method is applied to asynchronous packet data transmission from a number
of users over a shared channel. Experimental transmission of two musical signals is reported.

Algorithms for generation of chaotic signals and for chaotic communications systems are proposed and implemented both in software and hardware. Experiments via physical wire channel with the use of Digital Signal Processors (DSP) are carried out in the speech--frequency band. I. INTRODUCTION Last years active researches of an opportunity of chaotic...

Digital techniques for chaotic-signal generation and for information transmission by means of chaos are discussed. The effect of a limited precision of digital signal processors (DSPs) on the properties of generated signals is studied. A chaotic oscillator is simulated with a 16-bit signal processor. A nonlinear-mixing transmission scheme is implem...

The necessity of simultaneous access to one communication channel
by many users, has led to the development of the corresponding
standards: FDMA, TDMA and CDMA. In multiple-access systems, chaotic
signals are used only as efficient and versatile means of quasi-noise
signal formation. In such applications, important and attractive
features, such as...

A scheme for high-rate information transmission using dynamic chaos is proposed, which allows one to perform the transmission of more than one information bit per chaotic sample. The sensitivity of the scheme to the noise in the communication channel is studied, and a method for improving its noise immunity is introduced.

A theoretical possibility is demonstrated of transmitting analog signals in the radio band with the help of chaotic signals and conventional methods for the data reception and transmission. A model of a communications system using dynamic chaos is introduced, and the results of its computer simulation are analyzed. An experimental breadboard model...

Communication scheme for high rate information transmission using
dynamical chaos is suggested. A novel method is presented for encoding
and transmitting digital data by means of chaotic dynamical systems.
This scheme is demonstrated to transmit more than one bit per chaotic
sample. The main features and the robustness of the suggested method
with...

This paper presents experimental results of wire-line and wireless analog information transmission in RF band via chaos using standard signal formation and reception methods.

Synchronization modes are investigated in ensembles of interacting
maps with chaos. For certain types of the map couplings, simple and
rigorous conditions for chaotic synchronization are obtained, determined
by only two parameters of order. The results of numerical simulation of
the processes of chaotic mode establishment and destruction are
presen...

Algorithms for generation of chaotic signals and for chaotic
communications systems are proposed and implemented both in software and
hardware. Experiments with the use of DSPs are carried out in the
speech-frequency bandwidth with the chaotic signals generated by chaotic
maps or by a chaos oscillator described by ordinary differential
equations

This paper presents experimental results of wire-line and wireless analog information transmis-sion in RF band via chaos using standard signal formation and reception methods.

Mathematical models are proposed, based on one-dimensional
piecewise-linear maps, in which complex dynamics, bifurcation phenomena
and chaos are used for information processing

In this report we discuss the ways for realization of code-division multiple access (CDMA) systems based on dynamic chaos. The use of chaos allows us to transmit infor- mation with the robustness close to that of the conventional spread-spectrum systems, and to obtain additional useful consumer properties. I. Introduction Conventional spread-spectr...

Bifurcation phenomena in piecewise-lin ear 1-D maps with stored information are studied. Synchronization as a possible way of information retrieval is suggested. Main properties of such a procedure are discussed. Previously (1-4), we proposed to use limit cycles and strange attractors of piecewise-lin ear maps as information "storehouses". Storing...

This letter presents experimental evidence of how to use Chua's circuit for creating a system transmitting complex analog signals such as speech and music. In comparison with other proposed systems our system has the advantage of being operational over a wide dynamic range of information to chaotic signal ratios.

External noise signal action on self-oscillation systems with inertia and delay is analyzed using the numerical methods. It is shown that in both the cases together with the stochastic movement development effects in action of an external noise signal the inverse phenomena can be observed when external noise results in bifurcations favoring establi...

The radiophysical models of autooscillatory systems are considered including the filters of low frequencies, the bandpass and rejection filters. The conditions of appearance of strange attractors in such systems are analyzed. The possibility of forming the bandpass chaotic signals with prescribed power spectrum is shown. The dependence of the spect...

Radiophysical models of self-excited oscillatory systems, including low-pass, bandpass and rejector filters, are investigated. The conditions under which strange attractors can arise in self-excited oscillatory systems are analysed. It is shown that it is possible for broadband chaotic signals with a specified power spectrum to be generated. The re...

The possibility of storing and recognizing information based on nonlinear dynamic systems is investigated. To this end a special kind of one-dimensional map of a section into itself is introduced whose stable cycles are in one-to-one correspondence with information blocks in the form of finite segments of symbols. Recognition of an information bloc...

The dimensional characteristics of strange attractors (SAs) were studied experimentally in an oscillator with delay feedback, consisting of a p-n-p-n nonlinear element, an amplifier, a delay unit, and a first-order low-pass RC filter all connected in series and closed in a ring. Results indicate that the SA dimension in real physical systems with d...

It is suggested that a generator with delayed feedback should be used to model some properties of developed turbulence. A prototype model of a generator is described; the results of an experimental study of its response to a change in the parameters are presented; and a numerical analysis of the oscillatory modes in the generator model is performed...

The existence of high-dimension (≈10) SA (strange attractors) in systems with delay is shown in this paper, and the dependence of the dimension value on the ratio of the system passband and delay time is investigated. An oscillator with a delayed feedback consisting of a nonlinear element, amplifier, delay unit and low-frequency first-order RC filt...

Experimental and theoretical results are presented on the use of an oscillator with delayed feedback to model certain properties of developed turbulence. A finite-dimensional model is constructed which approximates a distributed model of this oscillator. It is shown that the dimensionality of the strange attractor in the system is linearly related...

Experimental results are presented on the control of the self-modulation regimes of a single-mode microwave electron-beam/traveling-wave system by an external LF signal. Parametrically stimulated stochastization is investigated, and it is shown that chaos-stimulation processes are optimal when the filter resonant frequency deviates from the natural...

The stochastic dynamics of a ring-type self-excited oscillator, consisting of RC and RLC filters and an inertialess nonlinear amplifier, is investigated. The characteristics of the appearance and evolution of strange attractors (SA) are studied experimentally. The special features of the mathematical model, related to the nonlinear element asymmetr...

The paper is concerned with the stochastic dynamics of a ring oscillator consisting of RC and RLC filters and an inertialess nonlinear amplifier. The principles governing the formation and evolution of strange attractors are investigated experimentally. The characteristics of a mathematical model of a ring oscillator are analyzed with emphasis on t...

The role of asymmetry in the appearance and development of strange attractors (SA) is investigated for a ring-shaped self-oscillating system. The existence of two threshold values of the asymmetry parameter is demonstrated; the first of these is connected with the transition to chaos when asymmetry arises, while the second separates the region wher...

A nonlinear amplifier consisting of a nonlinear element connected in series with a linear amplifier is used to experimentally analyze how the random motion changes during a transition from one chaotic region to another in self-excited ring oscillators. Self-oscillations were excited for linear amplifier gains, M, of greater than 20 dB, and for gain...

Experiments were carried out with a self-excited oscillator, in which a vacuum tube was used as the nonlinear element. We could not detect any chaos in the system. To summarize we can draw the following conclusions. The transition to chaos in the system investigated occurs in accordance with a natural series, namely, via loss of stability of the li...

It is shown that a sinusoidal external wave acting on an electron-beam-traveling-electromagnetic wave system can lead to the excitation of unstable self-modulation components in the spectrum of the signal. Depending on the pump frequency, the transition to chaos may also occur as a result of successive doubling of the beam period, by self-modulatio...

The paper examines the characteristics of the transition from regular oscillations to stochastic oscillations in a determinate model of a self-oscillator with delay. It is shown that both periodic and stochastic complex self-oscillations can occur in an oscillator that is described by a nonlinear difference equation which is reducible to a second-o...

The technology of record, storage and processing of the texts, based on creation of integer index cycles is discussed. Algorithms of exact-match search and search similar on the basis of inquiry in a natural language are considered. The software realizing offered approaches is described, and examples of the electronic archives possessing properties...

In this report, we consider the maps with stored information as sources of spreading pseudo-random se- quences for communications systems. We show that applica- tion of such sources allows us to (i) have very rich set of code sequences; (ii) realize self-synchronization of the transmitter and receiver; (iii) guarantee security of the communications...

A method for multiple access using the structure of the unstable periodic orbits of chaotic attractor is proposed. Possible principles of the control and selection of unsta- ble cycle-codes are presented.

In this report, we investigate phenomena on the edge of spatially uniform chaotic mode and spatial temporal chaos in a lattice of chaotic 1-D maps with only local connections. It is shown that in autonomous lattice with local connections, spatially uniform chaotic mode cannot exist if the Lyapunov exponent λ of the isolated chaotic map is greater t...

Performance of wireless communication scheme with ultrawideband chaotic signals in the multipath channel is evaluated. We consider channel models based on multipath channel models elaborated by IEEE 802.15 working group for high bitrate (IEEE 802.15.3a channel model) and low bitrate (IEEE 802.15.4a channel model) ultrawideband wireless communicatio...