Written by tuzs
Editor-in-chief of Proceedings of Educational Communication Institutions, candidate of Technical Sciences, Vice-rector of Science of The Bonch-Bruevich Saint-Petersburg State University of Telecommunications, associate professor of Saint Petersburg National Research University of Information Technologies, Mechanics and Optics (Scopus ID: 6602633236)
Written by tuzs
You can read the electronic version of the journal issue - Volume 5, Issue 2, 2019.
Contents of the issue
- Bylina M., Chaimardanov P.
A Novel Measurement Technique of the Parameters of Erbium-Doped Optical Fibers
- Abstract: The paper presents a novel measurement technique of the parameters of erbium-doped fibers for modeling EDFA ampfiers in DWDM systems. A distinctive feature of the proposed measurement technique is the elimination of the effect of losses introduced by the passive components of the measuring schemes on the measurement results.
- Keywords: Optical Amplifier, Erbium Doped Fiber Amplifier, Dense Wavelength Division Multiplexing, Fiber Optic Transmission System, Measurement Technique, Optical Pumping
- Dashkov M., Yablochkin K.
Simulation of Polarization Backscattering Characteristics of Optical Fibers under Acoustical Action
- Abstract: At present distributed optical fiber acoustic sensors are needed for various applications. Those systems can be realized using polarization optical reflectometry. External mechanical action on optical fiber causes local birefringence changes and variations of optical axis orientation. Thus, analysis of polarized backscattered charac-teristics can be applied for detection and estimation of acoustic action parameters. Mathematial model of polari-zation characteristics of optical fiber and results of competer simulation are represented in paper.
- Keywords: optical fiber, polarization, birefringence, acoustic action, polarization reflectometry
- Dukelskii K.
Modal Discrimination in Microstructured Fibers with a Trigonal Cladding Symmetry
- Abstract: The design of a microstructured fiber with a core of 35 μm in diameter and a trigonal rotational symmetry, providing more than 50 % discrimination of the higher-order mode components, is proposed and numerically analyzed. In particular, by comparing the values of the effective area and the spatial intensity distribution of the fundamental and most competitive higher-order modes, it is shown that optical elements with a hole ratio of small and large diameter d2/d1 = 0,40 within the considered symmetry are capable of maintaining a quasi-single-mode regime of operation in the passive and active performance at the wavelength of 1550 nm.
- Keywords: microstructured fiber, large core, rotational symmetry, modal discrimination, effective mode area, overlap integral
- Agafonov S., Sivers M.
Integration of Satellite Radio-Navigation Systems and Indoor Positioning Systems
- Abstract: This article describes the relevance of expanding mobile object localization service area using wireless technologies, as well as improving the accuracy of localization. In order to solve this problem, has been developed a new algorithm of mobile object positioning data integration from several wireless systems giving an opportunity for mobile object localization both at open space and indoors. Efficiency of the developed algorithm was tested by the prototype of a hybrid positioning system. The usage of the algorithm for integrating data from different positioning systems allows not only to solve the problem of a mobile object location in junction region - from open space to indoor, but also to improve the accuracy of determining its true location.
- Keywords: wireless sensor networks, positioning accuracy, localization error, complex data processing, data integration, navigation systems, GNSS, IEEE 802.15.4a
- Vikulov A., Paramonov A.
Adjacent Channel Interference Model Analysis for Throughput Estimation of the IEEE 802.11 Networks
- Abstract: The article is devoted to the analysis of the adjacent-channel interference effects in the IEEE 802.11n/ac networks. In particular, a method is proposed for estimating the modulation and coding rate change as a function of the signal-to-noise ratio degradation in the adjacent channel interference conditions. A number of work scenarios have been selected, for which calculations have been performed, showing the estimated degradation of the data rate. In particular, a comparison of several common frequency plans for IEEE 802.11n/ac networks was made and their effectiveness was estimated from the perspective of adjacent-channel interference. Thus, the impact of extraneous networks has been estimated. The proposed method provides the opportunity to estimate the efficiency of the channel plan selected in order to improve the network operation.
- Keywords: wireless access network, IEEE 802.11, adjacent channel interference, signal to noise ratio, interference, signal attenuation
- Vladimirov S., Kognovitsky O.
Dual Basis Based Processing of Wideband Gordon–Mills–Welch Sequences Based on Two Linear Registers
- Abstract: The paper presents a dual basis based algorithm for processing and determining the initial states of the shift registers that form the Gordon–Mills–Welch (GMW) wideband sequences, which are characterized by their greater number and higher structural secrecy than the widely used M sequences. It is shown that the proposed algorithm, in contrast to the known ones, allows one to determine arbitrary initial states of shift registers, which expands the possibilities of using composite wideband GMW sequences for solving various problems when trans-mitting information via communication channels with noise.
- Keywords: wideband sequences, finite field, irreducible and primitive polynomial, linear feedback shift register, dual basis, trace function, decimation
- Vorobiev O., Prasolov A.
Evaluation of the Minimal Output Bit Width of the Decimator Filter in Digital Radio Receivers
- Abstract: One of the main parameters of radio receiver is sensitivity, which is limited from the bottom side by its own noise. To correctly calculate this parameter in digital radio receivers, it is necessary to deter-mine the noise figure of the digital signal processing unit, the main part of which will be digital filters. This article proposes a method for estimating the minimum bit width of the signal at the output of the filter decimator, in which the contribution of noise caused by truncation of the discharges at the out-put does not have a large effect on the signal-to-noise ratio.
- Keywords: FIR filters, digital filter coefficients, ADC, signal-to-noise ratio
- Ganbayev A., Filin V.
Simplified Dynamic Model of High-Power Field-Effect Transistors for Studying Switch Modes of Radio Frequency Devices
- Abstract: A computer-based static model of high-power field-effect transistors designed to operate in the large excitation signal mode is proposed (in switch mode operation). Based on a static model, a dynamic model is con-structed, describing the processes in switch mode transistor circuits. Modeling of radio-frequency generators on GaN-transistors with a switching frequency of 1 GHz has been carried out.
- Keywords: GaN-transistors, current mode class D, driving modes, piecewise linear model, switching mode
- Dinh T.D., Kirichek R., Koucheryavy A., Makolkina M.
Experimental Investigation of the Transmission of Multimedia Content for Augmented Reality Applications on the Basis of a Wireless Sensor Network
- Abstract: The article presents the results of an experimental investigation of the transfer of multimedia content for augmented reality applications based on a wireless sensor network. I EEE 802.15.4 and ZigBee protocol, as well as IEEE 802.11 (WiFi) are considered as a data transmission technology in a wireless sensor network. The choice of these technologies allows the interaction of Internet of Things devices with each other with the possibility of self-organization and delivery of data for augmented reality applications by relaying through intermediate nodes. In the first part of the article, the features of the transmission of voice and images through a network fragment are experimentally identified. During voice transmission, different languages are considered and the quality of perception at the receiving side is determined. In the second part of the article, the features of data transmission through intermediate nodes are experimentally identified for this purpose, full-scale and simulation modeling are used. On the basis of the conducted research and subsequent analysis, the dependences of the network operation parameters on the number of nodes in the network and the number of transitions are presented.
- Keywords: augmented reality, Internet of Things, self-organizing network, multimedia traffic, mesh-network, ZigBee, WiFi, QoS, QoE
- Lazarev V., Fokin G.
Positioning Accuracy Evaluation of Radio Emission Sources Using Time Difference of Arrival and Angle of Arrival Methods. Part 1
- Abstract: In this article positioning accuracy limits evaluation of radio emission sources using Time Difference of Arrival and Angle of Arrival methods are investigated. Different accuracy limits estimation metrics, such as Cramer-Rao lower band and Circular Error Probability, are presented. Accuracy limits estimation values, that depend on radiation sources position and its amount, are analyzed and analysis results as graphs in MATLAB are shown.
- Keywords: Cramer-Rao Lower Band, Circular Error Probability, Time Difference of Arrival, Angle of Arrival
- Alekseev V., Korzhik V.
Detecting of Audio Stegosystems with Information Embedding Based on Modulated Reverberation
- Abstract: Audio signal with embedding of information based on modulated reverberation is considered. The goal of such stegosystem commonly is to provide a copy right protection by digital watermarking but sometimes may be interesting also to detect a fact of hidden signal presence by means of steganalysis. Detecting of such stegosystems occurs impossibly when it is executed either by a listening of audio signal or by a observation of signal wave form if deph of embedding is very small. Therefore we propose a new detection algorithm based on properties of modulated reverberation. A performance evaluation of such algorithm is investigated by simulation in terms of the probability of missimg and the probability of false alarm.
- Keywords: stegosystem, reverberation of audio signal, steganalysis, cepstrum, correlation analysis
- Vladyko A., Lytaev M.
Path Loss Modelling in Millimeter Wave Radio Chanel by the Parabolic Equation Method
- Abstract: Modern wireless communication systems are increasingly penetrating into the millimeter wave rangres. Therefore, there is a need to develop reliable methods for calculating the characteristics of the wave propagation in the millimeter wave bands under various conditions. In this research we investigate the possibility of using the deterministic methods based on the numerical solution of the wave equation. This approach gives an opportunity to calculate and visualize such effects as diffraction, scattering, attenuation and refraction of the radio waves. Specific spatial structure of the radio channel can be taken into account. The well-proven parabolic equation method is used. The modern approaches to the numerical solution of the parabolic equation and the features of their application to the propagation of millimeter waves are considered. Numerical examples under various propagation conditions are given.
- Keywords: wave propagation, radio channel, millimeter waves, parabolic equation, 5G
- Dvornikov S.
Joint Distributions with Improved Contrast of Signal Components in Time-Frequency Space: Continued Review
- Abstract: An analytical review of known methods for increasing the contrast of matrices of joint distributions based on information about their entropy is presented. The possibilities of the Hough transform. Justified the transition to joint transformations of the Wigner-Hough Theoretical and practical results confirming the increase of the signal components contrast in the time-frequency space are presented. Examples of modeling are given. The advantages and limitations of these approaches are shown.
- Keywords: time-frequency distributions, Wigner-Hough transformations, methods of secondary processing of joint distributions
- Makarenko S., Ponamorev A.
Study of the Impact of Timeliness of Command Transmission in an Air Radio Communication Network on the Guidance Quality of an Aircraft at a Target
- Abstract: There are papers in which improving the air radio communication networks. However, this improvement of the networks is not related to gist of the target tasks that are performed with special purpose aircrafts. At the same time, the main task of an air defense aircraft is to point the aircraft at an air target. The purpose of the paper is to formalize and study the impact of the timeliness of command transmission in the network on the guidance probability of the aircraft on the target.
- Keywords: air radio communication network, targeting, probability of targeting, timeliness, aircraft
Written by tuzs
You can read the electronic version of the journal issue - Volume 4, Issue 4, 2018.
Contents of the issue
- Vladimirov S., Kognovitsky O.
Postprocessing in the Dual Basis Based Decoding of the Small Set Kasami Sequences.
- Abstract: Pseudo-random sequences of various types, for example, M-sequences and Kasami sequences, are widely used to synchronize transmitted data in modern digital transmission systems. It is proposed to use these sequences simultaneously for synchronization and addresation of subscribers, using special decoding methods. The article discusses a method for decoding sequences of the small Kasami family based on a dual basis using postprocessing of received code combinations.
- Keywords: Kasami sequence, Kasami sequence small set, dual basis, error probability
- Gezalov E.
Model of the Heterogeneous Hybrid Communication Network with Combined Access Protocol and Taking into Account the Reliability of Communication Channels
- Abstract: The hybrid communication network with heterogeneous on intensity of the incoming message flow and combined access protocol the ground subnetwork is considered. The process of failure and restoration of terrestrial and satellite channels is considered, and it is shown that the analysis of the inter-regional information transmission in a hybrid network, must be considered its influence on network characteristics. A model in a discrete-time of hybrid heterogeneous network with taking into account the reliability of terrestrial and satellite channels is carrying out.
- Keywords: hybrid communication network, local network, combined access protocol, buffer, heterogeneous traffic, packet, time window, service interval
- Dvornikov S.
Generalized Hybrid Scale-Frequency-Time Distributions in Time-Frequency Space: Continued Review
- Abstract: A review of the theoretical foundations of the synthesis of hybrid distributions, which are generalized representations with respect to frequency-time distributions of the Cohen class and scale-time distributions of the affine class, is presented. The methodology of synthesis and display of their generality with respect to known forms of joint descriptions of the energy distribution density in frequency-time space is analyzed. The theoretical validity of hybrid forms, called the scale-frequency-time distributions, is proved. Analytic approaches to their synthesis are generalized and high-performance analytical algorithms adapted to the methodology of digital signal processing are presented. Analytical expressions and results of experiments on signal processing with high nonstationarity of the behavior of their parameters on the observation interval are presented.
- Keywords: scale-time distributions, signal processing methods with high parameter non-stationarity, affine and Cohen class distributions, hybrid distributions
- Kovalsky A.
Technique and Algorithm of Operational Planning of Sessions of Satellite Communication on the Basis of Technology of Flexible Strategy of Management
- Abstract: In article the satellite communication system for the organization of steady management of orbital grouping of spacecrafts is considered. The purpose of work is aimed at providing requirements for bandwidth of the satellite communication system at the expense of the organization of effective planning of communication sessions. For the solution of a problem of optimum planning and operational distribution of a radio resource of the satellite communication system for the organization of steady management of orbital grouping of spacecrafts the algorithm on the basis of a method of local optimum control and a technique with use of technology of flexible strategy of management is offered. In the conclusion sentences on development of the system of decision support at operational distribution of a radio resource of the satellite communication system are created.
- Keywords: satellite communication system, optimum planning of communication sessions, operational distribution of a radio resource, technology of flexible strategy of management
- Lozinskaya V., Molokovskiy I., Yaremko I.
Wireless Network Statistical Wideband Channel Model for the Industrial Enterprises’ Various Environments Conditions
- Abstract: The article describes a wideband wireless network channel for the an industrial enterprise conditions organization problem. It is shown that well-known multipath models are used to estimate the parameters of such channel, for example, the signal power at the receiver. It is noted that due to the complex characteristics of the industrial environment, such models are not always possible to use. The model presented in this work allows us to estimate power delay profile, taking into account the environment of an industrial enterprise. It is shown that this model allows to increase the accuracy of the estimation of the receiver location in comparison with the existing ones.
- Keywords: wideband wireless network channel, industrial enterprise conditions, the signal power at the receiver, multipath model, power delay profile
- Makarenko S.
Hierarchical Clustering of Telecommunication Network to the Independent Routing Areas for the Purposes to Ensure Stability
- Abstract: A generalized theoretical approach that increases stability of telecommunications network is presented in the paper. The approach is formalized as a basic method and two special methods. This approach is based on adaptive multilevel clustering of the network to separate routing areas. Thus, destabilized segments of network are isolated in the areas, and the high stability routing protocols are used in the segments.
- Keywords: networks, telecommunication network, routing protocol, stability, network stability, network convergence, convergence time, clustering, network clustering, hierarchical clustering
- Makarov L., Protasenya S.
Computer Simulation of Image Reproduction of Double Electric Layer of a Power Source.
- Abstract: Declaring existence of theoretical bases of the choice and development of typical designs of galvanic cells and accumulators, the problem of modeling of the power supplies possessing a set of the comparative indicators received by computing means on the basis of fundamental thermodynamic indicators of a condition of an atomic design of electrodes and electrolyte is updated. Procedures of creation of computer model of reproduction of an image of a double electric layer are established, on the established indicators, various power supplies providing a priori designing.
- Keywords: the power source potential, a computer model, atomic structure, double electric layer
- Makolkina M., Manariyo S., Muthanna A.
Investigation of IPTV Video Streams Delivery via SDN Using MEC Technology
- Abstract: With the advent of new technologies, such as augmented reality and the Internet of Things, the popularity of video transmission services over networks is significantly increasing. In order to provide video services with the appropriate quality, it is necessary to develop new communication networks mechanisms, which allow increasing the network efficiency. The article proposes an algorithm that improves video delivery efficiency by using Mobile Edge Computing (MEC) technology in a controlled mode over Software-Defined Networking (SDN). The algorithm performance was studied using a simulation model. According to the simulation results, the quality of video transmission is significantly improved by reducing network delays.
- Keywords: Internet Protocol Television (IPTV), video traffic, Software-Defined Network (SDN), Mobile Edge Computing (MEC), quality of experience (QoE)
- Fokin G.
Survey of Radio Communication Channel Models for Unmanned Aerial Vehicles
- Abstract: In this study we reviewed the models of the communication channel with unmanned aerial vehicles based on the latest experimental studies under the auspices of NASA. To formalize the radio channel models, they were divided into various functional scenarios: above water, in hilly terrain, in the mountains, and also in the city and suburb. For each scenario, various characteristics of radio channel measurements were analyzed, such as: propagation loss, consideration of multipath components, root-mean-square delay expansion, stationarity interval, Rice K-factor, correlation of received signals. The results of the analysis allow us to justify the choice of methods for processing navigation measurements in positioning tasks using the air segment based on unmanned aircraft.
- Keywords: radio communication channel, unmanned aerial vehicle, propagation loss, multipath component count, root-mean-square delay spread, stationarity interval, Rice K-factor, correlation of received signals.
- Chervinsky V.
Optimization Algorithm for IPTV Service Provider's Network with Combination of Unicast and Multicast Modes
- Abstract: Paper describes the modern approach to the provision of digital television services IPTV. Various modes of broadcasting video streams are considered, including Unicast and Multicast, their advantages and disadvantages are analyzed. The problems are considered that may arise for providers when designing a network with IPTV service provision. The optimization algorithm has been developed for IPTV provider network combining Unicast and Multicast modes based on genetic methods. The algorithm and its main operators are described in detail. The examples of applying the genetic algorithm developed to the optimization problems for information and communication networks through simulation are considered.
- Keywords: IPTV digital television service, Internet provider, video stream, broadcast, optimization, genetic algorithm, infocommunication network, Multicast mode, Unicast mode, design, simulation
Written by tuzs
You can read the electronic version of the journal issue - Volume 5, Issue 1, 2019.
Contents of the issue
- Ananyev V., Demidov V., Leonov S., Nikonorov N.
Hollow-Core Antiresonant Fibers with a Large Effective Mode Area for Operation in the Near- and Mid-IR Spectral Regions
- Abstract: The data on the development and study of silica hollow-core microstructured fibers, the principle of operation of which is based on the phenomenon of antiresonant reflection of light, are given. For an optical element with a core of 46 μm in diameter, formed by six non-touching capillaries with a diameter of 20 µm and wall thickness of 2,8 μm, the existence of at least four regions of signal transmission in the wavelength range from 1 to 4 μm has been found. Using the results of numerical simulation and experimental data, it was shown that the obtained fiber is characterized by a practically single-mode mode operation with an effective mode field area of about 1000 μm2, due to the large attenuation level of the group of higher-order modes.
- Keywords: microstructured fiber, hollow-core, antiresonant reflection, fundamental mode, effective mode field area, attenuaion
- Andreeva E., Bylina M., Glagolev S., Dotsenko S., Chaimardanov P.
Properties of Temporary Optical Solitons in Optical Fibers and the Possibility of their Use in Telecommunications
- Abstract: In the fourth part of the paper, a theoretical study of the processes of propagation of pulses having the form of Gaussian functions and hyperbolic secant on a single-mode optical fibers with alternating signs of group velocity dispersions and taking into account losses was performed. Fundamental inaccuracies in widely used expressions to describe the processes of propagation of Gaussian pulses through optical fibers are revealed and refined analytical expressions are proposed. The paper contains a simulation of optical fiber communication systems at speeds of 10 and 40 Gbit/s using the OptiSystem and AltPhotonic Simulation Tool programs. The influence of the chirping value on the quality of communication is investigated. A comparison of fiber-optic communication systems using concentrated and distributed optical amplifiers is performed. Engineering formulas and recommendations for designing quasi-soliton optical fiber communication systems are proposed.
- Keywords: optical soliton, temporary optical soliton, single-mode optical fiber, optical fiber communication system, group velocity dispersion, self-phase modulation, chirping, Q-factor, optical amplification, solitons with a controlled dispersion, simulation
- Goryachev N., Rogozinsky G.
Modeling Method of Hardware Sound Synthesizers
- Abstract: The paper presents author’s original method of hardware synthesizers and sound processing devices modeling, taking the Yamaha TX81Z FM synthesizer as an example. The computer music language called Csound is used for the software simulation. The paper gives the basis of FM synthesis theory, the review of modeling method, and analysis of modeling results
- Keywords: sound synthesis systems, modeling, computer music languages, Csound, FM synthesis
- Pakhomov M.
Investigation of Influence of Electromechanical Characteristics of Electrodynamic Transducers on Sound Quality Perception
- Abstract: The two most noticeable types of distortion in an audio signal path – frequency and nonlinear – are frequently analyzed by researchers and developers in terms of auditory perception. The effect of transient distortion, though insufficiently studied, is evident in subjective listening tests when comparing dynamic transducers with similar frequency response and no audible nonlinear distortions. In the present study was conducted dynamic transducer measurements and subjective evaluations to define the critical factors based on the dynamic transducer’s electromechanical characteristics that affect transient distortion and determined relations between the factors’ values and subjective scores.
- Keywords: transient distortions, dynamic distortions, Thiele-Small parameters, attack time, peak-factor, dynamic range
- Al-Bahri M.S., Kirichek R., Sazonov D.
A Digital Object Architecture Based Internet of Things Devices Identification System Modeling
- Abstract: The analysis of the possibility of building a system for identifying devices of the Internet of Things based on the Digital Object Architecture has been carried out. A model of the system of resolution handle system of Digital Object Identification as a queuing system is proposed. The analysis of the existing system Handling. Is proposed an identification system model based on digital object architecture. On the basis of the developed model of the queuing system, an optimization experiment was performed and the configuration of the resolution system was obtained, allowing to reduce the time for resolving the device identifier. The software of the existing Handle System resolution was analyzed and ways of improving the algorithms with the aim of reducing the time for identifier resolution were proposed
- Keywords: Internet of Things, Digital Object Architecture, Digital Object Identification, Handle System, queuing system
- Zikratov I., Zikratova T.
Optimization of the Coverage Zone of Cellular Communication by Mathematical Programming
- Abstract: A method for planning a radio network by a cellular operator has been proposed. The urgency of the task is due to the desire of service providers to minimize the costs of the distribution and maintenance of the required number of base stations while ensuring the required signal / noise level within the coverage area. The problem is solved by a rational choice of the location of the repeater base points in several stages. First of all, an analysis of a site is carried out and a preliminary selection is made on it of a set of points where base stations can potentially be located. As a rule, this problem is solved using specialized geographic information systems. At the second stage, the calculation of the radio range is carried out, provided the location of the repeaters at the selected points. At the third stage, on the basis of preliminary calculations, the selection of the positions of the base stations is carried out directly. It is proposed to use a stochastic approach for a rational choice of positions. The expediency of this approach is due to the large number of random uncontrolled factors affecting the signal-to-noise ratio at the receiving point. In this case, the problem of optimal choice of position is considered as an extremal problem, in which the parameters of the conditions are random variables. The implementation of the method proposed by the authors in the paper is illustrated by the example of radio communication planning on a country-type site, which is intersected by two highways. As input parameters in the example, the length of the sections of roads crossing the coverage areas of the repeaters and the concentration of subscribers on the routes is used. The objective function and the system of restrictions are compiled in such a way as to ensure that subscribers are located within the coverage area and to minimize the areas of intersection of the coverage areas of the neighboring repeaters. The use of this technique will allow us to obtain a statistically optimal arrangement of base stations on a given piece of terrain, which is confirmed by simulation modeling.
- Keywords: radio communication range, coverage areas, planning optimization, position selection, cellular communication
- Kovalgin Y., Santos V.
Influence of DRM-Transmitter Operation Mode on the Quality of Audio Content Transmission in the Low and Medium Frequency Range
- Abstract: Based on the analysis of the ITU-R primary documents and the experience gained by the authors, the influence of digital audio data compression algorithms, the type of modulation of subcarrier frequencies in the OFDM block and code rate, as well as the signal-to-noise ratio during radio reception on the quality of the transmitted audio content is considered. Recommendations on the choice of the listed parameters are given.
- Keywords: DRM operation modes, transmitter, quality, audio content, speed, channel, code, compression algorithms
- Muhizi S., Paramonov A.
A Traffic Classification and Prioritization Model in Software-Defined Networks
- Abstract: As the number of networked devices and applications rapidly grows, particularly the Internet of Things applications, billions of devices are connected to the network and therefore managing the generated traffic becomes a needy task. Effectively managing these devices to support reliable, secure, and high-quality applications becomes challenging. The main solution to manage network traffic is the automatic classification of application aimed at identifying the semantic type of application by analyzing its network traffic and wide range of new features. This article proposes a model for dynamic network traffic classification in software-defined networks based on the modified k-means algorithm for network resources distribution to prioritized types of traffic, which allows network applications optimization.
- Keywords: software-defined networks, clustering, classification, prioritization, modified k-means algorithm
- Simonina O., Zank V.
Research of an Impact of the Guard Interval on the Wi-Fi Quality Parameters
- Abstract: The article shows that the type of traffic, bandwidth and guard interval in IEEE 802.11 technologies have a minor effect on the quality of service indicators. At the same time, the difference between the multi-service traffic service capabilities between IEEE 802.11n and IEEE 802.11ac is insignificant, and the gain from changing the guard interval can reach 10 % of network bandwidth. The study was conducted on a model and a real-life network.
- Keywords: IEEE, Wi-Fi, Guard Interval, QoS Parameters
- Fokin G.
Principles and Technologies of Digital Communication Based on Software Defined Radio: A Review of Modern Trends in the Field of Creating a Curricculum
- Abstract: Current trends in software-defined radio (SDR) penetration into science, production and education is determined by the appearance on the market of affordable and multifunctional software and hardware solutions. Analysis of the experience of a number of foreign universities suggests a new educational paradigm in the field of telecommunications and radio communications related to the direction of the SDR. From an educational point of view, the field of the SDR is interdisciplinary and covers the following courses: radio receiving and radio transmitting devices, digital signal processing, theory of electrical communication, programming and simulation modeling. The integrating role of the SDR course is to develop a system approach for analyzing and synthesizing a modern transceiver with the ability to programmatically implement most of the functions of the physical layer and with final approbation of its work in real field conditions. The purpose of this work is to review current trends in the creation of a curriculum for training specialists in the course “Principles and Technologies of Digital Communication Based on Software Defined Radio”. Thus the work analyzes architecture and evolution of the SDR radio station, current trends and foreign experience in the use of SDR in education, the hardware structure of the radio receiver RTL-SDR, features of the implementation of the SDR transceiver in open source software. To assess the performance indicators of the SDR transceivers, the conclusion contains approach for half-natural experiment testing on the Keysight test bench.
- Keywords: SDR, SCA, FPGA, DSP, GPP, ASIC, transceiver, Keysight test bench
- Dvornikov S.
Methodology of Improving Forms of Representation of Joint Distributions in the Time-Frequency Space: Continued Review
- Abstract: A review of various approaches to improving the joint forms of representing the energy distribution of signals with a complex structure in the time-frequency space is presented. Including on the basis of the use of reassignment procedures, based on the results of secondary processing of marginal forms of joint distributions and their functions of high-order moment moments. The advantages and limitations of these approaches are shown.
- Keywords: time-frequency distributions, marginal distributions, affine class distributions, methods of secondary processing of joint distributions
- Кazhemskiy M., Sheluhin O.
Multiclass Classification of Attacks to Information Resources with Machine Learning Techniques
- Abstract: The article considers the classification of attacks on information resources using "classic" machine learning algorithms: k-Nearest Neighbors, Logistic Regression, Naive Bayes, Support Vectors, also ensemble methods: Decision Tree, Random Forest and Ada Boost. The research was conducted on the NSL-KDD data set using Python programming language libraries: scikit-learn, pandas and jupyter notebook. Data in the dataset were prepared for the research along with optimization of machine learning algorithm parameters. All fields in the dataset were marked with five classes, which correspond to four categories of attacks (DoS, U2R, R2L, Probe) and normal traffic (normal). A comparative analysis of the classification of each algorithm were made using different evaluation metrics. It was concluded that all the reasearched algorithms have shown insufficient efficiency in the conditions of data imbalance. It was proposed to perform additional actions on the initial dataset for better classification. The best results were demonstrated by the Random Forest algorithm.
- Keywords: multiclass classification, machine learning, attacks, classic algorithms, ensemble methods, scikit-learn, NSL-KDD
- Makarov L., Protasenya S.
The Fractal Simulation Image of the Quantum Generator
- Abstract: Development and creation of semiconductor devices updates a problem of the preliminary modeling allowing lowering substantially costs of carrying out scientific and technological research. In the presented material of work information approach on creation of fractal model of the semiconductor structure taking into account atomic designs of chemical elements providing a possibility of a priori research and calculation of standard indicators of working processes of the semiconductor is considered. The methodological basis of process of modeling of semiconductors is represented a basis for development of heterogeneous designs.
- Keywords: quantum generator, semiconductor structure, mathematical model
Written by tuzs
You can read the electronic version of the journal issue - Volume 4, Issue 3, 2018.
Contents of the issue
- Andreeva E., Bylina M., Glagolev S., Dotsenko S., Chaimardanov P.
Properties of Temporary Optical Solitons in Optical Fibers and the Possibility of their Use in Telecommunications. Part 3
- Abstract: In the third part of the paper, a theoretical study of the propagation processes of pulses having the form of hyperbolic secant has been carried out using special single-mode optical fibers with decreasing chromatic dispersion. Simulation has shown that the soliton regime is maintained at the longitude at considerable distances even in the presence of losses in the special fibers, which are compensated by discrete optical amplifiers. Using the simulation, it is also shown that instead of special fibers, several series-connected optical fibers can be successfully used with discretely decreasing group velocity dispersion (GVD). Quasi-soliton fiber-optic communication systems are also theoretically considered, in fiber-optic linear paths of which sections consisting of two optical fibers with different signs of GVD are used. And the residual GVD in the section has a negative sign. This allows, in combination with an op-amp, to realize a quasisoliton mode of operation in the fiber-optic linear path. Quasisoliton pulses are also called solitons with a controlled dispersion. Calculations and modeling using the OptiSystem allowed obtaining engineering formulas and recommendations for designing quasi-soliton fiber-optic communication systems.
- Keywords: optical soliton, temporary optical soliton, single-mode optical fiber, fiber optic communication system, group velocity dispersion, self-phase modulation, optical fiber with decreasing chromatic dispersion, optical amplification, solitons with a controlled dispersion, simulation
- Anufrenko A., Kanaev А., Login E.
Model of the Attacker's Influence on a Fragment of a Transport Communication Network Based on the Carrier Ethernet Technology
- Abstract: The transport communication network plays a key role in ensuring the transfer of traffic between access nodes. At the same time, modern Carrier Ethernet network technology, which implements a number of mechanisms for monitoring and managing the state of the transport communication network fragments, does not have built-in protection mechanisms against the targeted attack of the attacker on the communication network. In this regard, the task associated with the evaluation of the probability-time characteristics of the attacker's attack on the transport communication network, functioning on the basis of Carrier Ethernet technology, is actualized. The article examines the functioning of the Сarrier Еthernet transport network in terms of the impact on the computer-style attack "Substitution of the trusted object." A block diagram of the algorithm of the computer attack of this type will be revealed, as well as its mathematical model developed taking into account the profile model of the attack and the method of topological transformation of stochastic networks.
- Keywords: transport communication network, Carrier Ethernet, computer attack, substitution of the trusted object
- Dvornikov S.
Bilinear Scale-Temporary Distributions of Energy of the Affine Class in the Frequency-Temporary Space: Continued Review
- Abstract: The review of theoretical bases of synthesis of scale-time distributions of an affine class is presented. The methodology of wavelet transforms with an adaptive analysis window is analyzed in the interest of processing processes with high parameter non-stationarity. Analytic approaches to synthesis of distributions invariant to affine shifts are generalized. The generality of the scale-time and frequency-time distributions is shown. Analytical expressions and experimental results of the most known forms of affine class distributions are given.
- Keywords: scale-time distributions, methods for processing processes with high parameter non-stationarity, affine-class distribution, wavelet transforms
- Zhirov V., Orlov A., Smirnov A.
The Model of the Satellite Communication Radio Link in the High-Speed Satellite System
- Abstract: The article is devoted to the model of the satellite communication radio link in the high-speed satellite system. Unlike particular models, which take into account thermal noise, intersystem and adjacent interference, and meeting of readiness requirements with rainfall availability is controlled after the system reserve assessment, in the proposed model, the requirements for availability are explicitly taken into account in the form of a constraint. This makes it possible to set and solve the problems of optimizing the distribution of the frequency-energy resource of central earth stations and on-board retransmission complexes by the criterion of maximum bandwidth while meeting the requirements for the reliability of information transmission and the readiness of the duplex direction of satellite communications.
- Keywords: satellite radio link, frequency-energy resource, earth station, on-board retransmission complex, high-speed satellite system
- Kapralov D., Kirik D.
Stochastic Model of Meteor-Burst Radio Channel
- Abstract: The article proposes a stochastic model of a meteor-burst communication that differs from the known ones in that it takes into account the statistical nature of the occurrence of traces of various types. Based on the results of the studies, the initial values of the parameters of the quadrature com-ponents of the signal reflected from traces of various types.
- Keywords: meteor-burst communication, radio waves, stochastic model
- Makarenko S.
The Improved EIGRP Protocol for High Network Stability
- Abstract: The improved EIGRP routing protocol is presents in the paper. The improved EIGRP protocol is to use topological network redundancy and create backup paths. This protocol provides high network stability, if the network topology changes rapidly.
- Keywords: network, routing protocol, network stability, network convergence time, EIGRP
- Makarov L., Pozdnyakov А., Protasenya S.
Ergodic Model of Atomic Designs
- Abstract: The questions of natural science knowledge of the laws of Nature, actualizing the problem of posi-tioning atoms of chemical elements. Using the known physical concepts and methodology of in-formation retrieval of significant indicators of the event, an endogenous model of the atom is formed. A set of mathematical procedures characterizing the systemic nature of changes in the properties of atomic structures is proposed. A series of computational procedures for estimating the mass of atoms over the entire natural numerical series is implemented. The presence of an un-countable set of atomic constructions possessing the fundamental property of exponential reduc-tion of the lifetime is established.
- Keywords: atom, model of atomic structure, system of atoms
- Murtala I., Tiamiyu O.A.
Comparative Analysis of Low Latency Anonymous Communication Systems
- Abstract: With the rapid development and general acceptance of the Internet globally, concealing one’s identity (remaining unknown) for protection and security reasons while communicating over Internet is of great concern. Thus, anonymity has turned into an essential and legitimate aim in numerous applications, including anonymous web surfing, location based services, and E-voting. This study compares existing implementation of various low latency anonymous communication systems, more precisely, onion routing techniques, with respect to user requirements such as performance, reliability and usability to determine their level of efficiency.
- Keywords: Internet security, anonymity techniques, secure browsing, user experience
- Pakhomov M., Rozhnov V.
Method for Quantitative Evaluation of Auditory Perception of Nonlinear Distortion. Part 2. Metric for Music Signal Tonality and its Impact on Subjective Perception of Distortions
- Abstract: In the work presented the topic of taking into account the spectral characteristics of the test signal when evaluating the subjective perception of nonlinear distortions is disclosed. The most significant characteristic – tonality is chosen and a quantitative measure of this characteristic is proposed – the tonality coefficient. Subjective listening tests were conducted to determine the dependence of the auditory perception of nonlinear distortions on the tone structure of the signal and the spectral distribution of the noise-mask relationship.
- Keywords: multitone signal, nonlinear distortions, simultaneous masking, noise-to-mask ratio, tonality coefficient, linear multiregression model