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• ERROR ESTIMATION FOR MULTIPLE COMPARISON OF NOISY IMAGES

  A.N. Karkishchenko, V. B. Mnukhin

  2021-07-18

  Abstract ▼

  The aim of this work is to study the effect of noise on the image on the quality of comparison of a
  finite set of images of the same shape and size. This task inevitably arises when analyzing scenes, detecting
  individual objects, detecting symmetry, etc. The noise factor must be taken into account, since the
  difference between digital objects can be caused not only by the mismatch of the compared images of
  real objects, but also by distortions due to noise, which is almost always takes place. This differenceturns out to be proportional to the level of the noise component. The main result of this article is an
  analytical estimate for the probability of a given level of error, which may arise in the multiple comparison
  of a finite set of commensurate digital images. This estimate is based on a low-level comparison,
  which is a pixel-by-pixel calculation of image differences using the Euclidean metric. In this case, a
  standard assumption is made about the independent normal noise of image intensities with zero mathematical
  expectation and a priori established standard deviation in each pixel. The evidence presented in
  the article allows us to assert that the obtained estimate should be regarded as sufficiently "cautious"
  and it can be expected that in reality the scatter of the measure caused by noise in the image will be
  significantly less than the theoretically found boundary. The estimates obtained in this work are also
  useful for detecting various types of symmetry in images, which, as a rule, lead to the need to calculate
  the difference of an arbitrary number of commensurate digital areas. In addition, they can be used as
  theoretically grounded threshold values in tasks requiring a decision on the coincidence or difference of
  images. Such threshold values inevitably appear at various stages of processing noisy images, and the
  question of their specific values, as a rule, remains open; at best, heuristic considerations are proposed
  for their selection.

• APPLICATION OF HYBRID METHODS FOR NUMERICAL SOLVING OF ORDINARY DIFFERENTIAL EQUATIONS FOR ANALYSIS OF SELF-OSCILLATING CIRCUITS WITH VARIOUS DYNAMICS

  А.М. Pilipenko

  2026-02-27

  Abstract ▼

  Ensuring the accuracy and stability of computer simulation of electronic devices is an important problem in their design. The greatest difficulties in simulation of electronic devices arise in the case of the analysis of self-oscillating circuits, since mathematical models of such circuits can be stiff and oscillating at the same time. The aim of this work is to develop an efficient numerical method for solving ordinary differential equations that provides higher accuracy of time domain analysis for various types of autogenerators compared to existing methods. The proposed method is a hybrid method and is based on the well-known Gear and trapezoidal methods used in simulators of electronic circuits. To evaluate the accuracy of the proposed method and known methods a generalized model of a self-oscillating circuit was used for which an analytical solution was determined in the steady-state operating mode. The accuracy of the numerical solution was determined based on the analysis of errors in estimating the main parameters of the oscillatory process – the amplitude and frequency of oscillations. A comparative analysis of errors in estimating the amplitude and frequency of oscillations in autogenerators demonstrates the high efficiency of the proposed hybrid method for analyzing both harmonic oscillators and relaxation oscillators. A further increase in the accuracy of the hybrid method is possible using implicit Runge-Kutta methods (Rado IIA and Lobatto IIIA subclasses), which have L- and P-stability, respectively. It should be noted that with an increase in the order of accuracy of implicit Runge-Kutta methods, the computational complexity of these methods increases, but for the Rado IIA and Lobatto IIIA subclasses the increase in computational complexity will be minimal.

• ANALYSIS OF CHARACTERISTIC FOR CED CIRCUITS BASED ON REDUNDANT ENCODING METHODS

  D. V. Telpukhov , T. D. Zhukova, A. N. Schelokov

  2020-11-22

  Abstract ▼

  Typically, soft errors that occur in electronic equipment under influence of various destabilizing
  factors, were under the scrutiny of memory element developers. But recent research in this
  area shows that with development of microelectronics, the number of soft errors in combination
  circuits is increasing and soon their frequency of occurrence will be comparable to that in unprotected
  memory elements. Presently, to address this problem, special attention has been paid to
  methods based on control devices. These methods, by introducing additional structural redundancy,
  enable scheme to automatically detect and/or correct errors that occur in it. However, as a
  result of application of various methods of synthesis concurrent error detection (CED) circuits
  depending on initial parameters and internal structure of protected scheme devices possessing
  various efficiency and reliability characteristics are realized. However, as a result of application
  of various methods of synthesis CED circuits depending on initial parameters and internal structure
  protected circuit, the devices possessing different efficiency and reliability characteristics are
  realized. That is why there is a necessity to define and develop evaluation functions for analysis inorder to find the best method of synthesis CED circuit for certain device without any preliminary
  modeling. This work is devoted to development specification of structural redundancy and reliability
  characteristics evaluation functions on the example of CED circuits on basis of spectral and lowdensity
  parity-check code. The comparative and correlation analysis of analytical data with experimental
  values was carried out to evaluate efficiency of the functions obtained as a result of study.

• EVOLUTION OF RADIO OVER FREE SPACE OPTICAL COMMUNICATION UTILIZING SUBCARRIER MULTIPLEXING / AMPLITUDE SHIFT KEYING

  Hussein Ahmed Mahmood, Al-Karawi Hussein Shookor, K. Y. Rumyantsev

  2021-01-19

  Abstract ▼

  The high demand for increased bandwidth, data rate and quality in optical communication
  systems in modern applications. Radio over free space optics (RoFSO) is deemed a new design
  methodology over wireless systems and networks. This technique has to ensure data rates like ones
  presented by means optical fiber communication techniques in keeping with a portion of its arrangement
  cost. Such systems are implemented by combined radio signal (RF) with optical signal,
  which containing various wireless administrations and Free Space Optics (FSO) link. In this paper,
  the simulation and evaluation system of Subcarrier Multiplexing/Amplitude Shift Keying
  (SCM/ASK) transmitter for Free Space Optical Communication is proposed. 1Gb/s data Rate given
  to the system. Whilst 10 GHz radio frequency signal setting in electrical amplitude modulator.
  Thereafter, radio signal is added with 100 subcarrier channels of 10 MHz spacing channel at
  operated first channel frequency of 60 MHz. These subcarrier channels with 900 combined with
  10 GHz sin wave signal ( radio frequency ) at hybrid coupler, the combination of each subcarriers
  and radio signal are modulated by LiNb Mach-Zehnder optical modulator with 1550 nm wavelength
  continues wave laser signal at 10 dBm input power. The optical modulated signal (after
  optical modulator) is transmitted over a various free space optical link from 300m to 1km under
  the Atmospheric turbulence effect (the structure feature of the refractive index). The system is
  evaluated utilizing Opti system software with Q-factor and BER terminology. It is shown that the
  maximum optical distance for weak turbulence (
  at BER equal to 10-9 is
  950m, while the maximum optical distance for strong turbulence
  is 850m.

• ALGORITHM FOR TEMPERATURE CORRECTION OF VIBRATION DENSITY METERS

  O.V. Zatserklyanyi

  2021-02-13

  Abstract ▼

  In this article additional temperature error of vibration density meters in liquids and gases
  is reviewed. Particularly scrutinized are the effects of change in the temperature of the medium
  on the vibration frequency of the density vibration transducers. Main principle of operation
  and advantages of vibration density meters is described. The article analyzes and describes the
  existing algorithms of calculating density and active temperature compensation as well as the
  disadvantages of those algorithms. It points out to the significant limitations of temperature
  calibration diapason of the existing methods which relate to the necessity of using distilled water.
  Basing on the previous vibration transducer simulation and on the established main function of the elastic modules of the metal’ temperature properties a new thermal compensation
  algorithm, which does not involve liquid compensators, was introduced. Main advantages of the
  new algorithm are demonstrated. Those advantages emerge due to using vacuum as a medium
  surrounding the vibration transducer. One of the most notable benefits is significant extension
  of the calibrated temperature range. A possibility of applying the algorithm for calibrating density
  meters in extreme temperatures is introduced. Furthermore, formulas for calculatingthe
  value of the oscillation period of the converter which account for temperature changes (thermal
  compensation period) are presented. The advantages of using second order polynomial with
  zero linear term as a calibration function are also provided. Methodology behind conducting
  the experiments, types of equipment and measuring instruments are described in detail. Resul ting
  experimental data for vibration transducers made of three different metals is presented. The
  obtained data is analyzed, which led to a conclusion that application of suggested algorithm of
  thermal compensation of liquid and gases density meters’ vibration transducers is feasible and
  expedient.

• TRANSMITTING DATA IN 3D WIMAX CHANNEL BASED ON SISO-OFDM AND MIMO-OFDM

  V.P. Fedosov, Jaleel Sadoon Jameel, S.V. Kucheryavenko

  2021-02-13

  Abstract ▼

  This paper considers infrastructure to wireless mobile communications using Advanced-WiMAX. In this paper, the productivity performance throughput experienced the mobile users is compared in the cases of 3D SISO and 3D MIMO-channel models within a large urban cell. Re-cently, there has been substantial work and interest to expand MIMO and SISO-processing by taking into consideration in the design the elevation plane in addition to the azimuth dimension, Since the evaluation of elevation MIMO and SISO performance in 3D-channel design is needed. Bit-level simulation is performed for the channel in WiMAX operating at 2.5 GHz. The results indicate the accuracy of the 3D channel model, and the correct estimation of the 3D channel is showed. The difference in higher predicted capacity for the 3D channel model has resulted in the small-scale parameters for the SISO-case and the lower spatial correlation parameters for the MIMO-case. Different mobility speeds, the effect of the Doppler shift, several paths and the signal attenuation at a distance and with increasing frequency has been carried out in this study. Simulation runtimes are measured concerning the multi-section modulation types for both systems SISO and MIMO. Noise immunity is adversely affected by an increase in the number of spatial streams. The noise immunity is also affected by the increase in the number of antennas at the transmitters and receivers.

• APPLICATION OF THE HAMMING CODE IN THE PROBLEM OF INCREASING FAULT TOLERANCE OF LOGIC CIRCUITS

  D.V. Telpukhov , T.D. Zhukova, A.N. Schelokov, P.D. Kretinina

  2021-11-14

  Abstract ▼

  Currently, when designing integrated circuits, developers have to take into account a very
  large number of dissimilar factors that are associated with ensuring the necessary performance
  characteristics, occupied area, energy efficiency, yield, convenience of subsequent testing, requirements
  for universality, autonomy, and so on. One of the main factors is the reliability of operation.
  This criterion comes to the fore for critical applications, as well as for devices operating
  under the influence of destabilizing factors. To provide increased reliability, different methods and
  approaches are used at different levels of abstraction. Some of them can be applied at the design
  stage. One of the main methods for improving the reliability of integrated circuits at the design
  stage is the use of tools from the theory of error-correcting coding.The traditional field of application
  of error-correcting codes is the control of the integrity of stored and transmitted information.
  Combinational logic circuits, on the other hand, change information and do not have storage elements.
  Combinational logic circuits implement look-up tables at the gate level, which unambiguously
  assign a certain output value to each input action. Nevertheless, the use of error-correcting
  codes for constructing error-tolerant combinational circuits turns out to be very effective. This
  requires the introduction of additional combinational blocks into the circuit, which provide coding,
  decoding, control, and in some cases correction of errors arising in the circuit. The paper
  investigates the efficiency of using Hamming codes in relation to the construction of fault-tolerant
  combinational circuits. The paper considered classical Hamming code and his main modification -
  weighted code with summation without carries for the implementation of fault-tolerant combinational
  circuits. Means have been developed for the automated synthesis of fault-tolerant circuits
  based on these codes. Structural redundancy and reliability characteristics of the resulting circuits
  are investigated. Comparison with traditional method triple modular redundancy is carried out.
  Estimating functions are derived for redundancy and the probability of missing an error.

• SELECTING FEATURES OF THE MODEL TRANSFORMATION CHARACTERISTICS FOR AN INTELLIGENT PHYSICAL QUANTITY SENSOR

  S. I. Klevtsov

  2021-11-14

  Abstract ▼

  The paper discusses the issues of choosing the type and parameters of the model of the transformation
  characteristic of an intelligent sensor of physical quantities using the example of a pressure
  sensor. The transformation characteristic of an intelligent sensor is a mathematical, algorithmic
  and software for calculating a physical quantity based on electrical signals that come from the measuring
  channels of the sensor. The model of the conversion characteristic should be adapted to the
  configuration of the conversion function of the sensor's sensitive element and the behavior of this
  function under the influence of external destabilizing factors. The paper considers various models of
  the conversion characteristics, identifies the features of their application, advantages and disadvantages,
  attainable levels of approximation error of the real characteristic, which affect the final
  measurement accuracy of the smart sensor. Smart sensors are used for measuring physical quantities
  in various technical systems and the requirements for measurement accuracy in real-life tasks are
  different. The measurement accuracy is largely determined by the degree of approximation of the real
  characteristics of the sensor by its mathematical model. The more complex the model, the more difficult
  it is to implement in the sensor, and the higher the measurement cost. Therefore, it is important
  to control the conversion characteristic approximation error in order to use the sensor efficiently. To
  control the approximation error of the transformation characteristic of an intelligent pressure sensor,
  it is proposed to use the method of multi-segment spatial approximation, and use models of linear or
  nonlinear spatial elements as segments. The basic mathematical expressions, the error control
  scheme are determined. The results of modeling are presented, which show the possibility and advantages
  of using the method for the formation of spatial models of the transformation characteristics,
  which are adaptive to changes in the real transformation function of the sensor, take into account
  the influence of external factors on the measurement results. In addition, the method allows you
  to modify the current spatial approximation model by changing the types of local spatial elements
  and, thus, to control the measurement error

• RANDOM ERROR OF PULSE DURATION MEASUREMENT WITH OSCILLATIONS AT THE TOP BY MULTI-THRESHOLD DURATION METERS

  D.V. Belyaev, D.E. Gubarev, К. Е. Rumyantsev

  2021-12-24

  Abstract ▼

  In systems for automatic measurement of the duration of video pulses, various devices for amplifying
  and shaping pulses of a normalized level are used, the duration of which is equal to the duration
  of the input signals. A rough measurement of the duration of video pulses can be made with onethreshold
  meters. More accurate are multi-threshold and floating-threshold meters. Pulse duration
  meters have found wide application in electronic warfare equipment, in measuring technology. The
  variation in the shape of electrical signals does not allow the use of a single measurement method,
  which is the best for all shapes, therefore, the search for technical solutions that satisfy the conflicting
  requirements continues: a wide range of durations and duty cycles. The aim of this work is to
  carry out a mathematical analysis of the random error in measuring the pulse duration with oscillations
  at the top by multi-threshold duration meters. In the course of the work, the results of a numerical
  experiment were obtained to measure the duration of a pulse with oscillations at the top using
  multi-threshold duration meters. And also a comparison was made of four multi-threshold duration
  meters for the investigated pulse shape. The calculation results are presented for a signal dynamic
  range of 60 dB and an amplitude quantization step of 3dB and 12 dB.

• SELECTION OF THE SENSOR CONVERSION CHARACTERISTIC MODEL FOR CONTROLLING THE ERROR IN THE MEASUREMENT OF PHYSICAL QUANTITIES

  S.I. Klevtsov

  2022-08-09

  Abstract ▼

  On the example of a pressure sensor, the problem of selecting a model and parameters of
  the conversion function of a microprocessor sensor is considered. The conversion function is
  based on a mathematical model that associates the electrical signal coming from the sensor's
  measuring transducer with the value of a physical quantity. The model of the conversion function
  of a microprocessor sensor must repeat the real spatial dependence of the electrical signal on the
  measured value and take into account the influence of external factors, such as temperature. Microprocessor
  sensors are used to measure the parameters of an object with a given accuracy. The
  main contribution to the measurement error is made by the inaccuracy of the approximation of the
  real transformation function by its model. The need to achieve the optimal level of parameter
  measurement error in the system, taking into account the complexity and cost of measurements,
  requires the control of the sensor error. For this purpose, various models and methods of approximation
  are presented. For efficient error control, a method of multi-segment spatial approximation
  based on models of linear or non-linear spatial elements is proposed. The error control procedure
  is formulated. The procedure for using the model of multi-segment spatial approximation
  of the transformation characteristic for pressure calculations taking into account the influence of
  temperature is based on the combined use of linear and non-linear spatial elements within the
  same model. The segment type selection procedure should begin with an assessment of the possibility
  of using a linear spatial element first, and if it is impossible to meet the accuracy requirements,
  an analysis of the use of a non-linear element. The method allows you to change the types
  and configuration of spatial elements and in this way influence the measurement error. The advantages
  of this approach are confirmed by the simulation results.

• MODEL OF SELF-OSCILLATING CIRCUIT FOR TESTING NUMERICAL METHODS OF TRANSIENT ANALYSIS IN SPICE-SIMULATORS

  А. М. Pilipenko, А. V. Agabekyan

  2022-08-09

  Abstract ▼

  At present time the problem of developing methods for numerical analysis of RF circuits in the
  time domain remains actual because the known Gear and trapezoidal methods used in SPICE simulators
  have a number of significant disadvantages. To evaluate the effectiveness of new numerical methods,
  special test problems are needed to determine the accuracy of methods in various operating modes.
  Numerical analysis of self-oscillating circuits in the time domain offers the most difficulties for circuit
  simulation programs (SPICE-simulators) since models of self-oscillating circuits can be both oscillatory
  and stiff simultaneously. The aim of this work is to create the model of a self-oscillating circuit that allows
  to quantify the accuracy of numerical methods. In accordance with the aim, the following problems
  are solved: the features of the numerical analysis of classical self-oscillators in SPICE-simulators are
  investigated; the generalized mathematical model of self-oscillating circuits is described; the universal
  circuit model of self-oscillating circuits for SPICE-simulators is presented; the quantitative accuracy
  assessment of numerical methods of transient analysis in SPICE-simulators was carried out. The model
  proposed in this paper makes it possible to determine the relative errors of numerical methods in the
  harmonic oscillations mode, in the relaxation oscillations mode, as well as in the «mixed» mode, when
  the circuit response contains both exponential components with different rates of change and quasiharmonic
  components. The obtained results confirm the high accuracy of the trapezoidal method in the
  mode of harmonic oscillations, and the Gear method in the mode of relaxation oscillations. The relative
  errors in determining the amplitude of oscillation using these methods for the corresponding operating
  modes do not exceed 3%. At the same time, in the «mixed» mode, the relative errors in determining the
  amplitude of oscillation for both methods can reach 100%, that confirms the need to use additional
  options or special methods of numerical analysis in SPICE-simulators.

• PARAMETRIC MATCHING OF INSULATION MONITORING DEVICES AND DC DISTRIBUTION SYSTEMS

  А. V. Khludenev

  280-289

  2025-07-31

  Abstract ▼

  The aim of the study is to develop a method for parametric matching of insulation monitoring
  devices, unearthed DC distribution systems and discrete inputs of relay protection.
  The use of unearthed DC distribution systems for power supply to relay protection devices
  and other responsible consumers makes it possible to ensure high reliability and safety during their operation. It is necessary to ensure uninterrupted power supply to these consumers
  even in the event of a ground fault in one of the DC distribution network poles. Insulation
  monitoring of the network poles and the prompt execution of repair work when the insulation
  resistance falls below the critical level set by the response value, are a guarantee of high
  reliability of power supply. The article discusses the reasons leading to dangerous levels of
  pole voltage unbalance and false triggering of relay protection discrete inputs during ground
  faults of the signal lines connected to them. A method based on multivariate DC analysis is
  proposed to determine the matched insulation monitoring response value with the DC network
  parameters and discrete inputs parameters, when the conditions for the occurrence of
  such accidents are excluded. The influence of insulation monitoring devices in a DC system
  on pole voltages unbalance and relay protection operation is also considered. A modification
  of the insulation monitoring active method is proposed, which does not create additional pole
  voltage unbalance and risks of relay protection misoperation. The operating range of the
  static characteristics of the pole voltages and leakage current measuring transducers is narrowed
  in the grid unbalanced modes by using a modified active insulation monitoring met hod.
  Estimates of the increase in the insulation resistance measurement error arising in these
  modes are obtained

• ADAPTIVE ALGORITHM FOR PROCESSING SPATIAL-TEMPORAL SIGNALS WITH REED-SOLOMON CODING FOR A THREE-DIMENSIONAL MODEL OF A WIRELESS RADIO COMMUNICATION CHANNEL

  V.P. Fedosov , Mohammedtaqi M. Jawad Al-Musawi Wisam , S.V. Kucheryavenko

  81-90

  2025-07-24

  Abstract ▼

  Reducing the probability of errors in message transmission is important in satellite, wireless and space communication systems. Reducing the probability of bit errors in a wireless communication system is possible by using encoding of the data being sent. Using channel encoding allows detecting and correcting errors in message transmission in a noisy channel. The aim of the work is to study the effect of using Reed-Solomon codes and the algorithm of space-time signal processing in a receiver using an adaptive antenna array on increasing noise immunity in wireless radio communication systems. In the presence of complex signal propagation paths, this allows performing spatial filtering in channels with reflections. The adaptation method, considered in this paper, is based on the theory of vectors and eigenvalues of the spatial correlation matrix. For Reed-Solomon codes, the simulation results show a significant decrease in bit error rates due to the correction of transmission errors. By using adaptive algorithms for single-input multiple-output orthogonal frequency division multiplexing (SIMO-OFDM) and multiple-input multiple-output MIMO-OFDM systems together with the Reed-Solomon code for the transmitted message, the signal-to-noise ratio for a fixed bit error level was increased to 8 dB and 5 dB, respectively. The results show that the adaptive algorithm with simultaneous use of the Reed-Solomon code can increase the throughput while significantly reducing the error probability. Under conditions of multipath signal propagation, it can be argued that the use of adaptive space-time algorithms improves the noise immunity of the receiving system during signal processing.

• ADAPTIVE ALGORITHM FOR PROCESSING SPATIAL-TEMPORAL SIGNALS FOR DATA TRANSMISSION IN 3D WIMAX CHANNEL BASED ON SIMO-OFDM PRINCIPLES

  V.P. Fedosov, Al-Musawi Wisam Mohammedtaqi M. Jawad, S.V. Kucheryavenko

  2025-01-30

  Abstract ▼

  The development of the telecommunications industry is focused on the use of wireless broadband
  communication systems that allow increasing the speed of information transfer. New technologies with
  high transmission capabilities have been developed to solve this problem. Limitation of the signal spectrum
  and signal fading in Fresnel zones due to multipath components in a wireless system deployed in
  densely built-up urban areas are significant problems in the design of wireless communication systems, as
  well as the occurrence of the Doppler effect due to the movement of the mobile station and signal attenuation
  during propagation in the channel in different frequency ranges. To increase the speed and throughput,
  it is possible to use the procedure of transmitting and receiving signals to form channels with one
  input and several outputs SIMO (Single Input Multiple Output), providing spatial filtering when choosing
  the path with the maximum signal power. The article presents the analysis and modeling of data transmission based on the SIMO system of the 3D WiMAX wireless channel. The results of comparison of signal
  processing by this method with and without the adaptive algorithm, obtained by the criterion of maximum
  signal-to-noise ratio (SNR) are presented by the dependences of the probability of occurrence of a bit
  error (BER) on the signal-to-noise ratio (SNR). As a result of modeling, it was concluded that for the same
  system, the probability of error is sensitive to a change in the modulation type, in other words, BER
  changes in accordance with a change in the type of signal modulation. It can also be concluded that SIMO
  systems are sensitive to multipath signal propagation for the same modulation type, and BER increases
  with an increase in the number of receivers since the signal-to-noise ratio SNR decreases.