Items of № 8, 2020

The Electrosvyaz Magazine is one of the leading science & technical magazines in Russia.

INFORMATION MODEL OF THE EDUCATIONAL PROCESS: PROBLEMS AND SOLUTIONS

Keywords: educational process, information model, volume of knowledge, time of knowledge transfer, information theory, potential difference, automated educational content management system, Internet.

The article is devoted to the problem of developing a constructive model of the educational process, taking into account new significant factors that have formed in the context of global digitalization. An information model of the educational process has been developed, which makes it possible to assess the key indicator — the training time. Some new factors influencing the key indicator were identified and taken into account. Situations when the educational process is impossible or stops are considered. The directions for improving the quality of the educational process are formulated.

FEATURES OF ADJUNCT TRAINING IN MILITARY UNIVERSITIES

Keywords: military universities, Military Academy of Communications, adjunct training, defense of a thesis, publication activity.

The article analyzes the state of adjunct training in military universities on the example of the Military Academy of Communications. It is shown that the transfer of adjunct training to one of the levels of higher education had a negative impact on the quality of thesis work and especially on the timing of their submission to dissertation councils. Several measures have been proposed, the implementation of which will optimize the work of the scientific and pedagogical teams of military universities in terms of improving the adjunct training.

NETWORK STRUCTURE SELF-SIMILARITY PROPERTIES AND ITS MODELING FOR INTERNET OF THINGS HIGH-DENSITY NETWORK

  • Eu.V. Tonkikh, FSUE NIIR, deputy head of a department; et@niir.ru
  • A.I. Paramonov, Saint-Petersburg State University of Telecommunications (SPbSUT), professor, Dr.Sci.(Tech.); alex-in-spb@yandex.ru
  • A.E. Koucheryavy, SPbSUT, professor, Dr.Sci. (Tech.); akouch@mail.ru

Keywords: self-similar structure, network structure, modeling, wireless network, Internet of things, high-density network.

The paper considers an approach to modeling the heterogeneous structure of high-density networks. The use of geometric fractals for modeling the structure of the network is proposed and an example of using the Hilbert curve for this purpose is given. A method for constructing a model of the network of high-density Internet of things is proposed and simulation results are presented. The proposed model and the results obtained can be useful in 5G networks modeling.

TRAFFIC OFFLOADING METHOD FOR V2X/5G NETWORKS BASED ON THE EDGE COMPUTING SYSTEM

Keywords: V2X, edge computing, MEC, 5G, traffic offloading.

The V2X (Vehicle-to-Everything) system structure has been developed, which allows, based on 5G network, to organize interaction between road infrastructure objects, unmanned and highly automated vehicles, pedestrians, and other networks. For efficient operation in conditions of dense vehicle traffic, the V2X system uses the mobile edge computing technology and a traffic offloading algorithm, which allows managing the data load on the edge cloud servers. Simulation results for various scenarios showed that the proposed structure and offloading algorithm can significantly reduce data transfer delays and system power consumption.

THE METHOD OF SUBSTANTIATING A RATIONAL NUMBER OF BACKUP COMMUNICATION CHANNELS IN AN INFORMATION AND TELECOMMUNICATIONS NETWORK

Keywords: information and telecommunications network, backup channel, solution of optimization operations, logical-probabilistic method, minimal orthogonal disjunctive form, structural function, matrix numbers, vector optimization.

A method of substantiating a rational number of backup communication channels in the information and telecommunications network (ITCN) is considered. The problem of determining the structure of backup channels is formulated. An example of solving the problem of failure-free operation of ITCN is given. A method for solving the complex problem of structural redundancy of the ITCN has been developed.

SYNTHESIS OF A SIGNAL-INVARIANT ALGORITHM FOR ESTIMATING THE AVERAGE POWER OF A GAUSSIAN NOISE OF UNKNOWN INTENSITY

  • A.A. Boldyrev, Zhukovsky-Gagarin Air Force Academy (AFA), adjunct; boldyrev140479@mail.ru
  • A.A. Buben’shchikov, Zhukovsky-Gagarin AFA, lecturer, Ph.D.; kleo_cesar@mail.ru
  • I.D. Klyuchnikova, Zhukovsky-Gagarin AFA, research assistant

Keywords: autocorrelated handling, measurement, receiving channel, correlative handling, estimation, noise, radio monitoring, radio-electronic conditions, average power, phase detection, electromagnetic environment.

The actual problem of testing the radio signal reception channel from the point of view of the interference environment is solved. The results of the synthesis of an algorithm for estimating the average power of the aggregate Gaussian interference in a receiving channel with an unknown intensity, invariant to the presence of a signal in it, and a variant of a technical solution implemented on its basis are presented. The novelty of the proposed approach consists in the application of autocorrelation and correlation processing of the input process in the form of an additive mixture of a signal with unknown shape and a Gaussian noise for measurement an a priori unknown average noise power. The measurement is based on distinction in dispersions of an interfering (noise) component on outputs of autocorrelated and correlative processing channels. This distinction allows us to determine the unknown average interference power.

SIGNAL NOISE IMMUNITY IN ALAMOUTI SYSTEMS TAKING INTO ACCOUNT PARAMETERS OF MULTIPATH COMMUNICATION CHANNELS

Keywords: Alamouti system, multipath communication channel, signal fading, noise immunity of signal reception, spatial diversity of antennas.

The paper offers the method of analysis of the Alamouti system, the simplest MISO system in which at the transmitting end of the communication line only two transmitting antennas with a certain spatial diversity are used to eliminate the interference of the rays arriving at the receiving site. The method is based on the study of the physical features of radio wave propagation and allows taking into account the specific characteristics of multipath propagation paths between the transmitting and receiving stations. The Alamouti system allows the reduction of fluctuations in the level of the signal entering the input of the demodulator, completely or partially eliminating the interference of the rays coming to the input of the receiver. The paper offers formulas that allow us to estimate the energy of the communication line, necessary to ensure the required reliability of signal reception, the influence of the location of the transmitting antennas relative to the propagation path of the radio waves (along or across the track), as well as the amount of necessary spatial diversity of the transmitting antennas at which the maximum possible noise immunity of signal reception can be ensured.

MODELING THE INFLUENCE OF RZ AND NRZ MESSAGE ENCODING ON INFORMATION TRANSFER IN OPTICAL FIBERS

  • V.E. Karlin, Siberian state university of telecommunications and information sciences (SibSUTIS), postgraduate; vkarlin@mail.ru

Keywords: optical fiber, fiber-optic communication lines, nonlinear effects, four-wave mixing (FWM), wavelength division multiplexing (WDM), bit error rate (BER).

Results of numerical experiments on simulation of signal propagation with spectral multiplexing in G.652 and G.655 optical fibers taking into account both linear and nonlinear effects are presented. In the presented computer models, the signal transmitted through the fiber optic transmission system is generated by a random sequence generator in the RZ- or NRZ-code and examined by the spectrum and error rate analyzers at the output of the optical fiber. The OptiSystem software environment is used to create computer models.

DESIGN OF COMPLEX BAND-PASS FILTERS BASED ON PROGRAMMABLE ANALOG INTEGRATED CIRCUITS

Keywords: programmable analog integrated circuit (FPAA), complex band-pass filter, AnadigmDesigner2, integrated circuits on switchable capacitors.

This article describes the method of calculation and implementation of a complex band-pass filter with the specified coordinates of the poles of the LF-prototypes based on field programmable analog array (FPAA) of company Anadigm. Modeling was carried on with the help of CAD AnadigmDesigner2. An example of implementing a complex third-order Butterworth filter on FPAA is described.

DESIGN OF CONCATENATED FEC DECODERS FOR FPGA

  • D.V. Bosomykin, FSUE NIIR, Scientific and Technical Center for Development of Complex Radio Systems (STC DCRS), director; dvb@niir.ru
  • Eu.A. Lopatin, FSUE NIIR, STC DCRS, consultant, Ph.D.; eal@niir.ru

Keywords: FPGA decoding, noise-immune codes, fiber-optic communication lines, fiber-optic communication lines, decoding algorithms.

FPGA’s implementation stages for decoders of fiber-optic FEC following ITU-T G.975.1 recommendation are considered. Each of the discussed options has its high-quality characteristics (resource capacity and performance).

SIMULATION SCHEME MODELING OF THE SUPER-SPEED TIME BUFFER

  • A.M. Sazhnev, SibSUTIS, department of radio engineering devices, associate professor, Ph.D.; epus201@sibsutis.ru
  • L.G. Rogulina, SibSUTIS, department of radio engineering devices, professor, Dr.Sci.(Tech.); rogulina_59@mail.ru

Keywords: simulation, gallium arsenide field-effect transistors, Schottky diode, clock buffer, superfast buffer.

The results of simulation of an ultra-high-speed clock signal buffer based on gallium arsenide n-channel transistors in OrCAD are presented, which fully meets the following requirements: high technical characteristics, application flexibility, low cost, small size, high frequency, and high efficiency. The given behavioral models allow the use of any software environment for circuit modeling.

MONITORING SYSTEM TO ENSURE THE ELECTROMAGNETIC SAFETY OF HOUSEHOLD OBJECTS

  • Eu.V. Titov, Altai State Technical University, associate professor, Ph.D.; 888tev888@mail.ru

Keywords: electromagnetic pollution, measurement of parameters of electromagnetic fields, automated control, visualization of the electromagnetic environment, computer simulation, electromagnetic safety.

It is proposed the method of forming pictures of the danger of electromagnetic radiation in a limited space with sources of electromagnetic fields according to the criterion of the allowable stay time. The article shows the results of experimental studies of the electromagnetic field from personal computer monitors, optical mice, and multifunctional devices printer-copier-scanner. Computer models of the electromagnetic environment are presented in the form of pictures of the distribution of the electric field strength at a frequency of 30 kHz.

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