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• MICROWAVE MODELS OF INTERFERENCE LOGIC ELEMENTS

  A.G. Bykov, I.V. Oshkin, V.B. Profe, S.A. Stepanenko, K.V. Trotsuk, E.V. Tjapkov

  2022-01-31

  Abstract ▼

  In the modern world interference logic gates (ILG) are an integral part of computers in the
  modern world. One of the most important tasks of developers of new computing technology is to
  reduce the duration of logical operations. This ensures the perfomance of various computing systems
  used in large objects modeling with a large number of details in various industries and in
  processing a large amount of information. A possible way to solve this problem is to use ILGs
  based on the element base of the optical wavelength range. These models microwave ILG are being
  developed for implement the functions of ILG based on a microstrip line in the ultra-high frequency
  (UHF). The paper presents the result of modeling, engineering, manufacturing and testing models of microwave ILG which form a complete functional basis. A numerical simulation microwave
  model ILG, which implements the functions “AND“, “XOR“ and “NOT“, has been carried
  out. The model consists of four types microwave functional units: circulators, single-stage ring
  power adder and power take-off elements, which are directional couplers, with lateral coupling
  and with a given branch coefficient. The finite integration method in the time domain for numerical
  system modelling is used to confirm the operational principle of ILGs and their realizability.
  ILG mock-ups implement the functions “AND“, “XOR“ and “NOT“. The identity of the intensity
  values corresponding to the logical “0“ and “1“, generated by different elements, is observed.
  The execution duration of logical operations is determined by the duration of the pulse propagation
  in the waveguide. The use of reactive elements in the design of the ILG makes it possible to
  minimize the loss of microwave energy during the propagation of an electromagnetic pulse.

• IMPROVING INTERFERENCE IMMUNITY OF GROUND-TO-AIR RADIO LINKS BY ADAPTIVE ROUTE MODIFICATION OF A UAV RELAY BASED ON INTERFERENCE ENVIRONMENT ANALYSIS

  А. А. Shmidt , V.R. Bikbulatov , D.N. Polyakov , А.А. Tkhakakhov

  2026-04-29

  Abstract ▼

  The relevance of the work is driven by the increasing intensity of electronic countermeasures in the tactical command echelon, where traditional relay communication methods with fixed routes fail to ensure the required interference immunity and signal security. The objective of this study is to develop a method for adaptive route control of a UAV relay based on continuous monitoring of the electromagnetic environment in order to improve interference immunity of ground-to-air radio links. The primary method employed is multi-criteria flight path optimization with adaptive weighting coefficients, simultaneously considering three criteria: minimization of interference levels at the relay operating frequencies, ensuring radio accessibility with network correspondents, and reduction of detection probability by enemy electronic warfare assets. To reconstruct the spatial interference pattern from a limited set of onboard measurements, several interpolation and extrapolation methods are examined: inverse distance weighting, radial basis function interpolation, and statistical extrapolation based on a spatial correlation function. A cyclic operational procedure for the adaptive routing system is developed, comprising data collection, construction of a three-dimensional interference map, prediction of its evolution, calculation of the optimal trajectory, and monitoring of the maneuver outcome. Simulation results show that the proposed method increases the signal-to-interference ratio by 1.5–2 dB on average and up to 8 dB in the worst-case scenario compared to fixed-route flight. The practical significance lies in the possibility of implementing the proposed method using existing UAV platforms and radio-electronic equipment without fundamentally new technical solutions.

• NEURAL NETWORK TECHNOLOGIES IN THE TASKS OF MONITORING THERMOFLUCTUATION PROCESSES OF A CABLE LINE TAKING INTO ACCOUNT THE INFLUENCE OF INTERFERENCE

  N.K. Poluyanovich, M.N. Dubyago

  2021-02-13

  Abstract ▼

  The article is devoted to the assessment of the influence of magnetic interference, in the
  study of thermal fluctuation processes in the dynamic current load mode of a power cable line
  (SCL). On the basis of such artificial intelligence methods as neural networks and fuzzy logic, the
  thermal resistance of SCL insulating materials determining the throughput of the cable line of
  electric power systems was investigated. A comparative review of the currently existing traditional
  non-destructive methods for predicting thermal processes in SCR showed that most of the methods
  have a low prediction accuracy, as well as have a high degree of complexity and a large number
  of necessary computational operations to obtain the necessary data for predicting thermal processes
  in SCR. Also, most forecasting methods are not able to work in real time, which is an extremely
  significant drawback. To solve this problem, it is necessary to resort to forecasting systems
  that are based on artificial intelligence using machine learning methods. The method of artificial neural networks (ANN) seems to be the most promising today. The need to develop a more
  perfect method for analyzing the aging of SCR insulating materials is shown. The urgency of the
  problem of creating neural networks (NN) for assessing the throughput, calculating and predicting
  the temperature of SCL cores in real time based on the data of the temperature monitoring system,
  taking into account the change in the current load of the line and the external conditions of heat
  removal, has been substantiated. A neural network has been developed to determine the temperature
  regime of the current-carrying conductor of a power cable. A comparative analysis of the
  experimental and calculated characteristics of temperature distributions was carried out, while
  various load operating modes and functions of changing the cable current were investigated. A
  neural network model was developed in Matlab Simulink for predicting the temperature of a cable
  core. The creation, training and modeling of the neural network was carried out using the Neural
  Network Toolbox. The model can be used in devices and systems for continuous diagnostics of
  power cables by temperature conditions.

• STUDY OF THE STABILITY OF THE MIMO-OFDM SYSTEM TO ACTIVE INTERFERENCE USING AN ADAPTIVE ALGORITHM FOR PROCESSING SPATIAL-TEMPORAL SIGNALS

  V.P. Fedosov , А. V. Tsirkulenko

  227-236

  2025-10-01

  Abstract ▼

  Modern communication systems often operate in a complex interference and signaling environment, while there are various ways to reduce the error of the restored signal. Some of the methods relate directly to mathematical processing algorithms in the receiver, however, there are other approaches based on spatial filtering of signals. In particular, in recent years, an approach based on the weighted processing of signals received from different antennas has been actively developed using the correlation matrix of the input signal, which makes it possible to use information from the antennas more efficiently by choosing an antenna with the maximum level of useful signal and lower levels of noise and interference, which is physically the formation of an equivalent radiation patterns of the receiving antenna array with a maximum on the path with the maximum level of the useful signal and minima on others. The application of this approach is of practical interest, especially in systems with active interference, for example, from electronic warfare stations, as it can improve the quality of signal recovery. Separately, it should be noted that in the case of active interference, a method based on the minimum RMS error of restoring the pilot tones should be used to select the eigenvector for weight processing (which is possible in OFDM), since if the maximum eigenvalue is selected, it is unknown whether it will be signaling or interfering if it is high. This paper presents an experimental study of an adaptive algorithm for processing spatiotemporal signals for a MIMO-OFDM communication system with different levels of active interference from an electronic warfare (EW) station. In this case, experiments are carried out both in the descending (Downlink, from the base station to the mobile) and ascending (Uplink, from the mobile station to the base station) channel using adaptation on both the BS and MS sides, and both. It is shown that the application of the algorithm can improve the quality of signal processing and reduce the bit error rate for a wide range of signal–to-noise ratios (SNR – signal-to-noise ratio), even with imperfect channel estimation (by pilot tones).

• OPTIMIZATION OF REMOTE DOPPLER RECEIVER’S PARAMETERS IN SEMI-ACTIVE RADAR SYSTEMS

  P.A. Dyatlov, K.K. Bagrat

  2021-02-13

  Abstract ▼

  This article discusses the issues of increasing the noise immunity of semi-active radar systems
  based on the use of transmitters for target illumination using harmonic radiation and remote
  Doppler receivers in conjunction with a central information processing station. This solution is
  not only the simplest from the point of view of hardware implementation, but also has such advantages
  as high speed and increased sensitivity, as well as the ability to search-free spatial and
  frequency processing of radiation. Of the shortcomings, it should be noted the low secrecy of the
  functioning of this semi-active radar system. The purpose of the work is to eliminate the indicated
  drawback by using frequency tuning in the illumination transmitter or when using several spaceseparated
  illumination transmitters operating according to a given frequency-time scheme in a
  semi-active radio-location system. In addition, the paper deals with the optimization of the main
  parameters of portable Doppler receivers of semi-active radar systems. In particular, the paper
  gives recommendations for reducing the blinding effect of a direct signal to a Doppler receiver
  and presents a set of measures aimed at increasing the range of action of semi-active radar systems
  up to forty kilometers. In this paper, we consider the case of operation of a semi-active radiolocation
  system operating in a limited spatial sector using one remote receiving point. The illumination
  transmitter, which is usually placed on a high-rise object, generates directional radiation,
  intended primarily for solving various tasks in the field of telecommunications, for example,
  providing mobile communications, relaying satellite information, etc. In this system, the illumination
  transmitter is used in as a signal generator for illumination of air targets

• SUBTRACTION OF BACKPROPAGATION INTERFERENCE BASED ON POLARIZATION IN UNDERWATER VISION SYSTEMS FOR OPERATION IN TURBID WATER

  N.А. Budko, А.Y. Budko, М.Y. Medvedev

  2022-08-09

  Abstract ▼

  The study of the sea depths in order to ensure safety, the effective use of underwater resources
  is an urgent task. The first part of the article briefly considers the physical phenomena and
  limitations that arise during the propagation of electromagnetic waves in the visible range in the
  underwater environment. It is shown that underwater vision systems (as a class of specialized
  technical vision systems - TVS) based on conventional CCD matrices face a number of fundamental
  limitations in terms of improving the efficiency of functioning in natural water of low transparency.
  In particular, the use of artificial light sources as part of underwater vision systems in turbid
  water leads to the occurrence of backpropagation interference (BPR), which leads to spurious
  illumination of the optical device matrix. As a promising direction in the development of underwater
  vision systems, it is proposed to use methods for subtracting POR based on information about
  the polarization of light. In the review part of the article, the latest achievements in this field are
  considered. The main part of the article presents the methodology for studying the proposed method
  for subtracting the POR based on a comparison of the results obtained by processing images
  with known methods for estimating the Stokes vector parameters DoLP and AoLP, which allow
  obtaining information about the degree of polarization and the prevailing polarization angles of
  the scene, respectively. The experimentally obtained results of processing an underwater scene in
  water of varying degrees of turbidity using the DoLP, AoLP algorithms and the proposed methods
  for subtracting the POR are presented. Distinctive features are the use of four rather than two
  polarization directions in calculations, as well as the original mathematical apparatus for processing
  signals from the machine vision camera matrix.

• THEORETICAL STUDY OF ESTIMATING THE PROBABILITY OF A CONNECTION IN SYSTEMS WITH BROADBAND SIGNALS AND FHSS

  D.I. Konkov , А. А. Schmidt , D.N. Polyakov , V.R. Bikbulatov

  285-294

  2025-07-24

  Abstract ▼

  The article is devoted to a theoretical study of the probabilistic characteristics of communication systems with broadband signals and pseudorandom tuning of the operating frequency in a complex electromagnetic environment. An analytical tool for calculating the communication probability is presented, taking into account the complex effects of multipath propagation, frequency-selective fading, and intentional interference. The dependence of the communication probability on the signal-to-noise ratio is investigated using integral expressions that take into account the normal power distribution at the input of the receiving device. A mathematical analysis of the transmission function of the communication channel as a complex characteristic describing the amplitude-frequency and phase distortions during signal propagation is performed. Theoretical models of synchronization processes are developed, including the stages of signal search, capture, and tracking, using the Markum function to describe the probability of signal detection against the background of Gaussian noise. Methods for optimizing the key parameters of the RFP system, such as the frequency tuning period, the total number of frequency channels, and the width of the protective frequency interval, are proposed. The theoretical foundations of adaptive control based on the maximum likelihood method and recursive filtering for estimating the parameters of the channel\are described. The energy efficiency of systems with RFP is studied, taking into account the frequency tuning losses and the necessary adjustment of the signal-to-noise ratio. A comprehensive indicator of the quality of a communication system combining probabilistic, energy, and time characteristics of the system is proposed. Analytical expressions are developed for estimating the intensity of synchronization failure based on statistical analysis of experimental data and calculation of the covariance matrix of measurement noise. The expediency of using reference signals to increase the reliability of measurements of communication channel parameters in adaptive control of the system is justified. Relations are derived for determining the duration of the synchronization window, taking into account the maximum allowable time of entering synchronism and the margin factor, which takes into account possible frequency instabilities of the reference generators.  The influence of the protective frequency interval on preventing inter-channel interference and ensuring electromagnetic compatibility of neighboring channels is analyzed. The presented theoretical results provide a scientific basis for the design of radio systems with increased noise immunity and can be used in the development of adaptive algorithms for controlling RF control systems in a dynamically changing electromagnetic environment, ensuring a balance between the reliability of information transmission and the efficiency of using frequency-time resources of the communication system.