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Abstract: Based on 3GPP and ITU recommendations, Tactile Internet is one of the main applications of 5G communication networks (5G / IMT2020). Tactile Internet represents a new paradigm of telecommunications, which can support the transfer of Tactile sensations, which is the main application of this concept. The article analyzes Tactile Internet applications, implementation problems and approaches to their solution.

Keywords: Tactile Internet, application, requirements, 5G.

DOI 10.31854/2307-1303-2019-7-2-12-20

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Abstract: Research subject. This article is devoted to studying the resolution time of the identifier of digital objects of augmented reality based on the architecture of digital objects, as well as studying the influence of this time on the quality of perception of digital objects by a person. Method. The architecture of digital objects is considered as a method of identifying digital objects of augmented reality, a simulation model of a fragment of a typical network of augmented reality technology based on the architecture of digital objects to study network delays is built. The main results. A table of identifier resolution time was received. Recommendations on the construction of augmented reality network are developed. Practical relevance. Assessing the impact of network latency arising from the identification of digital objects on the effective use of augmented reality.

Keywords: DOA, digital object, augmented reality, perception quality.

DOI 10.31854/2307-1303-2019-7-2-21-33

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Abstract: Today, Wi-Fi networks can be found almost everywhere: in homes, businesses, hotels, restaurants, transportation, streets, etc. Research subject. In this study, we analyze the performance of outdoor and indoor wireless local area networks. Method. To achieve this goal, the following empirical research methods were used: measurement, experiment, and comparison. Core results. In the first part of the study, experimental data on radio frequency spectrum usage around and inside St. Petersburg State University of Telecommunications are provided. The second part of the study is devoted to the peculiarities of outdoor and indoor Wi-Fi. The effective data rate, retry rate, and noise floor are compared for the 2.4 and 5 GHz frequency bands. Practical relevance. The obtained results can be used for design and optimization of outdoor Wi-Fi networks.

Keywords: IEEE 802.11, WLAN, outdoor Wi-Fi network.

DOI 10.31854/2307-1303-2019-7-2-34-45

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Abstract: Research subject. Devoted the VANET network architecture, based on SDN / MEC (software-defined networks / mobile edge computing) systems that can reduce network load and traffic density. Method. The developed algorithm is considered. A testbed experiment based on a model network was done. Core results. The article examined the possibility of temporarily placing an application in RSU to reduce the load on the transit network. The condition for temporary placement of an application is based on data on congestion of road sections from Google Map & Yandex monitoring systems and current statistics on Internet traffic. Practical relevance. The proposed architecture allows to optimal use of RSU/MEC resources and significantly reduces the delay and load on data transmission.

Keywords: Edge computing, VANET, Migration, load.

DOI 10.31854/2307-1303-2019-7-2-47-55

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Abstract: The goal of automatic gain control is to maintain a constant output power level. Automatic gain control systems are used in various communication systems, both analog and digital. However, for all the variety of digital automatic gain control algorithms, the adjustment of the control parameters during the simulation process in reality is often ignored. In practice, this can lead to long-term overloads with a large change of the input signal power. There is also the risk that the model used was designed to work in linear mode only. In nonlinear mode, its behavior may not always be predictable. Research subject. The purpose of this article is to analyze digital AGC system characteristics and to model its operation in Matlab. Method. As part of the study, a Matlab model of hybrid automatic gain control system was developed. Core results. It is shown that the control time of the digital automatic gain control system with a non-linear gain control characteristic does not depend on the amplitude of the input signal. The performance of the proposed digital model is limited by the dynamic range of the linear path and the analog-to-digital converter. The mathematical dependence of the response time of the model on the input signal level change is obtained, in which the time constant of the automatic gain control filter has been replaced by the time constant of the entire automatic gain control system. Practical relevance. A digital model of hybrid automatic gain control system is proposed, which will allow to simulate digital automatic gain control systems parameters for both small and large changes in the input signal level. The results of this work are relevant to the development of digital receivers for communication systems of various purposes.

Keywords: Digital automatic gain control, model, attack time, decay time.

DOI 10.31854/2307-1303-2019-7-2-55-64

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Abstract: The analysis of scientific works shows that today there is no generally accepted theory of technical and economic security of the system "personnel-rocket and space complex-environment". However, it should be noted that some elements of this theory are contained in the General theory of risk assessment in combination with the methods of actuarial mathematics, as well as in combination with the methods of assessing the technical and economic costs of the creation and operation of space assets. The known methods of technical and economic assessment of costs for the creation and operation of space objects are based mainly on the cost principle and are focused on the actual costs necessary for the development, production and operation of samples of space technology, space infrastructure with the inclusion of standard profit. At the same time, many of the known methods of technical and economic evaluation of the costs of the creation and operation of space objects can be divided into the following main groups: methods of calculation, normative and parametric methods and methods of expert evaluation. When studying safety issues and preventing accidents at the rocket and space complex, it is necessary to take into account the main features of their functioning, which consist in the mandatory accounting of the properties of maintenance personnel, the actual technical means of the rocket and space complex and the environment. A feature of the system "personnelrocket and space complex-environment" is the presence of a large number of information links that characterize its information efficiency. This scientific and technical article proposes new ways, methods and means to ensure the adoption of optimal (rational) decisions to prevent accidents, taking into account resource constraints on parrying emergencies. Models of some types of resources that are appropriate to use in carrying out technical and economic calculations to solve various problems of the security system "personnel-rocket and space complex-environment". Core results. The aggregate models of resources which are expedient to use for an assessment of technical and economic indicators of safety are developed. The problem of optimal choice of the level of accident-free SPACECRAFT in the process of flight operation with restrictions on safety using the criterion "efficiency-safety-cost" is solved, nomograms of interrelation of indicators for the criterion "efficiency-safetycost" are received». Practical relevance. The proposed models allow us to estimate the share of costs required to ensure the safety of service personnel, RSC and its components, as well as the environment.

Keywords: technical and economic analysis, safety methods, quality, reliability, personnel-rocket and space complex-environment, emergency situations, design, operation, flight tests.

DOI 10.31854/2307-1303-2019-7-2-65-84

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Abstract: Research subject. The article is devoted to the method of identification of multimedia content based on digital object architecture and a stand which demonstrates the work of the method. Method. The principle of identification data division and injecting data parts in random order to a different area of the file is considered. The analysis of existing solutions is performed. Core results. Stand for identification of multimedia content based on digital object architecture have been developed. This stand can write identifier to the multimedia file and read from it. Practical relevance. The developed stand for identification of multimedia content based on digital object architecture can be used to protect digital content from piracy.

Keywords: Steganography, steganography injection, DOA, REST API.

DOI 10.31854/2307-1303-2019-7-2-85-95