Showing papers by "St. Petersburg State University of Telecommunications published in 2016"

Indoor Positioning in WiFi and NanoLOC Networks

Abstract: In this paper we compare the indoor positioning techniques of RToF in nanoLOC and RSSI fingerprinting in WiFi networks experimentally and highlight the impact of orientation during primary measurement acquisition for increasing location accuracy in the case of NLOS and multipath signal propagation conditions. Resulting accuracy estimates confirm known results and reveal that radiomap construction with primary RSSI measurements in four angular directions can improve positioning accuracy by 0.5 m in comparison with traditional fingerprinting in deployed WiFi and location dedicated nanoLOC networks.

Positioning accuracy experimental evaluation in SDR-based MLAT with joint processing of range measurements

Abstract: In this paper we present an algorithm for multipoint positioning in multilateration (MLAT) radio navigation system and prove that taking into account redundant primary estimates such as sum of range measurements between the object of location and a pair of transceiver stations could improve single range accuracy estimation after joint processing with appropriate weighting coefficients. The approach for experimental evaluation is a testbed including four SDR-based transceiver stations, three of which perform primary measurements collection and one acts as the object of location estimation and measurement processing unit. Transceiver stations are working on National Instruments (NI) Universal Software Radio Peripheral (USRP) hardware with LabVIEW software, performing transmission, reception and processing of signals. Experiment was conducted in mobile scenario with slow pedestrian object of location movement and revealed position Mean Square Error (MSE) of one meter for range measurements with ten trial results accumulation.

The life cycle of vulnerabilities in the representations of software for telecommunication devices

Abstract: This article investigates the problem of search for software vulnerabilities in terms of their life cycle. Each point life of vulnerability determined by the state of software with form and content — software representation. A typical sequence of representations in the field of telecommunication devices is given. Description prototype of software tool for Methodological Support System for Development of Safe Software is given.

Applications of Augmented Reality Traffic and Quality Requirements Study and Modeling

Abstract: The further development of communication networks appears today on the basis of the concept of the Internet of Things. At the same time gaining popularity technology “augmented reality” that allows you to manage different objects and processes in networks. Sharing the “augmented reality” and the concept of the Internet of Things technology, requires the development of the new service model and traffic pattern and establishment of a new approach of the Quality of Experience estimation.

The application of neural network and spline wavelet models in the electroencephalogram analysis automation process

Abstract: The article focuses on the use of synthesized wavelets in the electroencephalogram analysis automation process. It describes the procedures for obtaining neural network and spline models proposed by the author. The advantages and disadvantages of the method are shown. The paper proposes a system of electroencephalogram analysis automation process based on the use of two levels of continuous wavelet transform. A detailed description of its operation is given. The paper describes a software package developed on the basis of the system. During the tests, the software feature detection accuracy (eye artifacts and pathological components) in the signal was 81.5%. It suggests the main areas for the developed system and package application, as well as ways for their further improvement.

Spectral and Luminescence Properties of Sols and Coatings Containing CdS/ZnS QDs and Polyvinylpyrrolidone

Abstract: Spectral and luminescence properties of sols and composition coatings containing cadmium and zinc sulfides and high-molecular polyvinylpyrrolidone have been studied. It is shown that the absorption spectra of colloidal solutions in the UV spectral range are determined by the quantum-confinement effect and exhibit a dependence of the absorption edge on the size of cadmium sulfide nanocrystals. The size of forming particles of metal sulfides has been found to decrease with an increase in the relative content of polyvinylpyrrolidone. It is shown that the order of mixing of the initial components when synthesizing sols also determines the difference in the size of forming particles and their spectral properties.

Fuzzy Model of Dynamic Traffic Management in Software-Defined Mobile Networks

Abstract: Nowadays, in mobile networks, latency-sensitive services may compete for the bandwidth of other services, thus degrading overall performance. Software-defined mobile networks opening many new possibilities for dynamic traffic management. This gives chances to ensure strict requirements of the service quality in changing conditions. We considered two requirements for the quality of service: bandwidth and latency. Providing the required bandwidth is relatively simple compared to the end-to-end delay, as its guarantee requires a complex model that takes into account the mutual influence of flows throughout the entire path. Our model includes the following metrics: maximum channel utilization, traffic priority, the number of “hops”. Fuzzy balancer module has been developed for the Floodlight controller in Java. This module calculates the weights of the links in accordance with the proposed method. Simulation network was held in Mininet environment. During the experimental implementation, it has been shown that simple algorithm based on mathematical apparatus of fuzzy logic allows dynamically adapting the network to the change of the traffic volume, as well as its structure.

Formation of the Instantaneous Information Security Audit Concept

Abstract: This publication covers the problem of formation the concept of the instantaneous information security (IT-Security) audits, including protection against zero-day threats. Various recent materials are presented to the actual problem of counter zero-day threats notes that “any process-driven people, is unreliable. In this situation it is proposed to use not only a technical methods to counter zero-day threats, but to offer a combined method based on the concept of instantaneous IT-Security audits. Methodological basis of this concept for instantaneous audits defined both ISO 27001 and ISO 19011 standards, which extended with the set of IT-security metrics for quantify the object protection level. In the example for one variable was demonstrated an increase in the rate of growth of the ISMS level variables with known IT-Security audits process.

On the spectrum of discrete Schrödinger equation with one-dimensional perturbation

Abstract: We consider the spectrum of the discrete Schrodinger equation with one-dimensional perturbation. We obtain an explicit form of scattering matrix and find an exact condition of the absence of the singular part of the spectrum. We also calculated the eigenvalue that appears if this condition is not true. In the last part of our paper, we give few remarks on the case of two-dimensional perturbations.

Analysis of the Packet Path Lengths in the Swarms for Flying Ubiquitous Sensor Networks

Abstract: The article gives an approach for estimating the packet path length between the nodes for Flying Ubiquitous Sensor Networks. Authors show that such networks may be represented as three-dimensional swarms of nodes. The mathematical models for the ball and cubic swarms are given, as well as the simulation approach for the other shapes. Also two types of network architecture are considered – direct transfer and multi-hop.

The four-level integrative model methodology of structural and parametric synthesis of system objects

Abstract: The aim of the article is to present the methodology of four-level integrative models of system objects structural and parametric synthesis. Integrative models are based on the methods of knowledge engineering, morphological analysis and synthesis, optimization theory and decision-making. The proposed models are the optimization models with the structural and parametric control. They contain mechanisms for formal submission requirements, axiomatically given set of structural and parametric solutions, the methods of calculating the characteristics of the object, algorithms for finding rational solutions on a given structure-parameter set. Four-level integrative model can be the basis for distributed multi-agent computer-aided design system of structural and parametric synthesis.

Organizing energy-and-information exchange between devices for controlling the shape of a transformable antenna, using fiber-optic technology

Abstract: This paper analyzes the possibility of transporting energy and information to the actuators of a space-based transformable antenna along a fiber-optic channel. The main technical and functional requirements of such a system are considered, along with ways to put it into practice. A prototype of a fiber-optic system based on commercially available components for energy-and-information exchange between actuators has been assembled and tested.

Development of model-analitical intelligence of information agents for reactive infocommunication environments

Abstract: The article deals with the problem situation in creation of model-analytical intelligence of information agents for reactive infocommunication environments. It is suggested a formal approach for resolving this situation. The article describes a formalization of the proposed approach. It contains information about models and methods of formalization. It is spoken in detail about the main stages of construction of object-oriented models of information agents for reactive environments. Much attention is given to key transformation of methods for the analysis of object-oriented models of information agents for reactive environments. It deals with methods of obtaining invariants for the verification of the model-analytical intelligence of information agents. In conclusion, the article describes providing quality assurance of information agents functioning in reactive environment through the use of their model- analytical intelligence.

Method and prototype of utility for partial recovering source code for low-level and medium-level vulnerability search

Abstract: The article describes a automated method for searching of low-level and medium-level vulnerabilities in machine code, which is based on its partial recovering. Vulnerability search is positioned in the field of telecommunication devices. All various and typical vulnerabilities in source code and algorithms for its search is given. The article contains examples of usage method and its utility. There is forecast to develop methods and utilities in the near future.

Application of slope-intercept diagram to determine the parameters of the nanocomposite field emitters in-situ

Abstract: The method of the field emission data online processing of materials, perspective for a nanoelectronics, is developed. The method is based on the slope-intercept diagram analysis of the current voltage characteristics registered during the experiment. It allows to build calibration grids of the microscopic emission parameters, such as work function, effective emission area and field enhancement factor, and and to estimate changes in the sample structure online.

Using the IEEE 802.11 Family of Standards for Communication between Robotic Systems

Abstract: The paper analyzes the possibility of using the IEEE 802.11 standards for communication between the elements of robotic systems in terms of radio frequency (RF) channels congestion exterior traffic. Keywords-robotic systems; communication; monitoring; frame; distribution

The linguistic support of morphological set modeling

Abstract: The aim of the article is to present the results of research in the field of linguistic software representation of the morphological set. Created linguistic support is based on the methodology of morphological analysis, context-free grammars and domain-specific languages. An unified method for representation of morphological set suitable for a class of objects whose structures can be represented as a set of elements and the relationships between them. Developed linguistic software allows you to create hierarchical parameterized model with minimal time spent.

Analytical model of chromatic dispersion effect in the time domain

Abstract: The investigation of chromatic dispersion effect on pulse propagation is of interest in high-speed optical transmission systems. But the chromatic dispersion effect hasn't an acceptable analytical description in the time domain. The analytical model of the dispersion effect in the time domain using a quadratic function approximation of nonlinear part of the propagation constant and the Fresnel integrals is proposed in this paper. It is shown that the obtained model is universal and it has a tuneable accuracy.

The emission characteristics of graphene in different modes of high-voltage power supply

Abstract: We found out the general laws of the current-voltage characteristics hysteresis behavior for emitters of different nanomaterials - graphene, nanotube. Comparison of two power supply modes showed that the IVCs change with growth and decrease of the scanning voltage amplitude in "fast" mode which correlates with current-voltage characteristic hysteresis in "slow" mode. Common patterns forms of current-voltage characteristics in different power supply modes were identified.

Optical filters for adaptive compensation of chromatic dispersion in high-speed optical transmission systems

Abstract: The increasing of transmission speed in optical fiber allows decreasing transmission cost of one bit of information. But with growth of transmission speed in optical communication line the efficacy of chromatic dispersion to signal grows accordingly. The most promising method of dispersion compensation is the adaptive signal processing in optical area. Methods of synthesis of integrated adaptive filters, which consist of Mach-Zehnder interferometers and ring resonators, are considered in this article. The relationship between a delay-line length of a filter and parameters of channel and line link which allows determining a minimum permissible length of the filter delay-line is established. Comparison of infinite impulse response filter and finite impulse response filter by complexity of implementation is performed.

Energy Expenditure Forecasting at Path Generation of Spherical Robots within Multi-Agent System

Abstract: Background: The present research is relevant due to gathering the experience associated with a practical use of a spherical robot as a chassis for placing the local environmental monitoring equipment and due to the revealed need to use such robots within groups. Therefore, the article is aimed at showing the connections between the parameters of the external environment and kinematic, power and energy characteristics of the spherical robot chassis. Method: The main approaches to the research of the present problem are the methods of the transportation vehicle motion theory which in their turn are based on theoretical mechanics and theoretical physics laws, etc. The methodologies enable to significantly simplify a non-holonomic task associated with a sphere motion and to reach kinetic, power and energy characteristics appropriate for a practical use. Findings: The authors have studied the questions related to the estimation of energy expenditure for the spherical robot motion in an arbitrary path, have offered the concept of energy expenditure chart and shown the principles of using such chart for generation of a path of a spherical robot which operates within a multi-agent system. The approach regarding the generation of energy expenditure chart based on the preliminary area survey using a spherical robot has also been studied in the present article. Improvements: The materials of this article are of a practical value when working on the development of the ground component of multi-component multi-agent systems regardless of the type of the agent chassis.

Making Mainstream Synthesizers with Csound

Abstract: For more than the past twenty years, Csound has been one of the leaders in the world of the computer music research, implementing innovative synthesis methods and making them available beyond the academic environments from which they often arise, and into the hands of musicians and sound designers throughout the world. In its present state, Csound offers an efficient environment for sound experimentation, allowing the user to work with almost any known sound synthesis or signal processing method through its vast collection of ready-made opcodes. But despite all this potential, the shared resource of Csound instruments still lacks quality reproductions of well-known synthesizers; even with its ability to generate commercial standard user interfaces and with the possibility to compile Csound instruments in such as fashion so that they can be used with no knowledge of Csound code. To fill this gap, the authors have implemented two commercial-style synthesizers as VST plug-ins using the Csound front-end "Cabbage". This paper describes their architecture and some of the Csound specific challenges involved in the development of fully featured synthesizers.

Analysis of Options of Cooperative Processing of Measurements in Long-Range Multistatic Radar System

Abstract: Background/Objectives: The study considers the options of cooperative processing of long-range measurements in multistatic radio-technical systems. The information on the sum of distances improves the precision of the estimated range. Method: The investigations employ simulation and statistical models describing the techniques of cooperative processing of the radar information for the case of three-station radio-technical system. Findings: The calculated range values include all measurements obtained by the multistatic system with their relevant weights. The investigations show the effects produced by the selected number of stations and by the precision of the original measurements on the formation of the resulting estimations under the conditions of different initial data that help achieve the preset precision within shorter intervals without the limitations of the object movement hypothesis. The new results of this study are represented by the equations that describe the slant distances in the course of cooperative processing of measurements with different types of the correlation matrix of the errors and for different options of data processing. It has been proven that the suggested option of measurement processing possesses high informational stability against any anomalous measurements. Applications/Improvements: The results of this study will be helpful for upgrading the existing radio navigation systems and for developing justified requirements to any prospective research studies in this area of investigation.

Cooperative Processing of Measurements in Pseudorange Radio-technical Finding System

Abstract: Background/Objectives: The relevance of the current research is determined by the intensive development of multilateration systems which are widely used in time-positioning support systems. The authors propose to use the cooperative processing of coordinate information. Methods: In the present article a procedure of obtaining the ranging position lines with regard to each station is studied using a theory of redundant measurements which enables to implement cooperative processing. It is shown that using the least squares method, one can obtain the estimation of the required range-measurement parameters containing a minimum value of mean-square error. Findings: In our opinion, the new results of the study show that a multilateration system with one query station which forms a range line of position and with cooperative processing of Time Difference Of Arrival (TDOA) and Time Of Arrival (TOA), in some cases it is characterized by the improved accuracy compared to hyperbolic and elliptic systems. Measurement processing method studied in the present article enables to expand a system work area with respect to the accuracy for multilateration systems with short length base (distances between receiver stations). The offered procedures of radar data processing allow for a formation of range position lines that are indirectly obtained based on hyperbolic and elliptic lines of position. Cooperative processing of measurements in TOA and TDOA finding systems enables to improve the accuracy of the indirect range measurement. TDOA and TOA measurements do not improve the accuracy of the indirect range estimation with the offered method of measurement processing since the accuracy remains constant regardless of the number of stations. Application/ Improvements: The study results obtained could be used to upgrade the existing systems of aircraft position estimation and to make reasonable technical demands on the systems under development.

Correlation Properties Comparative Analysis of Pseudorandom Binary Sequences and LTE Standard ZC Sequences

Abstract: The paper describes correlation properties comparative analysis of pseudorandom binary sequences such as M-sequences, Gold codes, Hadamard ordered Golay sequences and LTE standard ZC sequences. In particular, the research considers primary synchronization signal (PSS) and random access preamble. Generation processes and the special features of ZC sequence based signals used in LTE standard are shown. Autocorrelation and cross correlation functions of appropriate signals are presented, correlation coefficients are evaluated.

Intra-CPU Traffic Estimation and Implications on Networks-on-Chip Research

Abstract: General purpose networks-on-chip (GP-NoC) are expected to feature tens or even hundreds of computational elements with complex communications infrastructure binding them into a connected network to achieve memory synchronization. The experience accumulated over the years in network design suggests that the knowledge of the traffic nature is mandatory for successful design of a networking technology. In this paper, based on the Intel CPU family, we describe traffic estimation techniques for modern multi-core GP-CPUs, discuss the traffic modeling procedure and highlight the implications of the traffic structure for GP-NoC research. The most important observation is that the traffic at internal interfaces appears to be random for external observer and has clearly identifiable batch structure.

Electron transport in a multi-resonator system formed by constrictions of a quantum waveguide

Abstract: Resonant tunneling is known to emerge in ballistic electron transport in a quantum waveguide with two narrows (constrictions). Here we present results of numerical simulations of electron transport in a system consisting of two identical resonators produced by three narrows in a quantum waveguide. It is shown that, at small electron energies, the resonance peaks of one-resonator system split and the peaks width and their separation depend on the diameter (width) of the narrows. The processes of high energy electron transport, where the role of multichannel scattering with changes of transverse channels (quantum states) becomes substantial, have been investigated. In addition, resonant tunneling in a quantum waveguide with N + 1 delta potential barriers which produce N resonators has been considered. Numerical simulations show formation of band structure and the bands parameters-dependence on the potential barriers, which confirm the possibility of making quasi-one-dimensional crystal in a quantum waveguide with a number of narrows. The results of the study may find potential applications in designing various resonance devices based on quantum waveguides.

Increasing polarization stability of anisotropic single-mode quartz light guides with elliptical stress cladding

Abstract: In this paper, we discuss the polarization properties of anisotropic single-mode light guides with boron germanosilicate elliptical stress cladding It is shown that, for light guides with a diameter of 125 μm, an increase of ellipticity of the cladding from 053 to 06 does not result in a change in birefringence This phenomenon is due to the distortion of the correct shape of the ellipse With that in mind, optimizing the design of the light guide will allow us to decrease the h-parameter to 5×10-6 m−1

External focusing of nanosecond pulsed X-ray radiation

Abstract: The feasibility of efficient focusing of high-power pulsed X-ray radiation generated by explosive electron emission from carbon nanoclusters is shown by direct experiments with the use of polycapillary X-ray optics. It is shown that the X-ray spot in the focus of the polycapillary lens can be reduced to 1/20 of its initial size.