Written by tuzs
You can read the electronic version of the journal issue - Volume 3, Issue 4, 2017.
Contents of the issue
- Awgari F.S.A., Kubalova A., Maksimov A.
Microstrip Elliptic Filter with Implementation on the Resonators of Same Electric Length
- Abstract: A novel design method of stepped elliptic band pass microwave filter on the meter range with implementation on the lattice of associated microstrip lines is proposed. The method of a filter calculation using electromagnetic simulation is proposed. The results of the experimental study of the filter layout are presented.
- Keywords: elliptic filter, microwave filter, microstrip line, electric length, coupled microstrip line, bandpass filter, multiconductor line, electromagnetic simulation
- Bourdine A., Burdin V.
Dispersion Characteristics of the LP11 Mode of a Step-Index Optical Fiber with Kerr Nonlinearity
- Abstract: The work presents the derivation of analytical expressions for the dispersion characteristics of the LP11 mode of a step-index optical fiber with a Kerr nonlinearity for propagation conditions of this mode. The solution was obtained by using the Gauss approximation method. The estimates of the dependences from the optical intensity in the fiber of the propagation time and the chromatic dispersion of the first and second orders of the LP11 mode of a step-index optical fiber with a Kerr nonlinearity are presented.
- Keywords: optical fiber, lightguide, mode, mode spot radius, Gaussian approximation method, step-index profile, Kerr nonlinearity, time of mode propagation, chromatic dispersion
- Bylina M., Glagolev S., Diubov A.
Comparative Analysis of Direct and Coherent Detection Methods for Digital Information Optical Signals. Part 2. Coherent Detection
- Abstract: In the second part of the article, an analysis is made of the coherent reception of optical digital signals with different modulation formats: amplitude modulation, phase modulation, and quadrature-amplitude modulation. Signal-to-noise ratios and limiting detection capabilities for binary modulation formats are determined. The schemes of heterodyne and homodyne optical receivers are analyzed.
- Keywords: Direct reception, coherent reception, heterodyne receiver, homodyne receiver, single-mode optical fiber, modulation formats, photodetector, optical amplifier, photocurrent amplifier, fiber optic communication system, signal-to-noise ratio, detectability, phase-locked loop
- Gatchin Y., Demidov V., Dukelskii K., Zlobin P., Matrosova A.
Basic Technological Methods of Obtaining Mechanically Stable Low-Loss Single-Mode Microstructured Fibers
- Abstract: The influence of two technological approaches to the fabrication from a capillary stack of silica-based single-mode microstructured fiber with a core of 35 µm in diameter, intended for operation in conditions of multiple bending, on optical losses and mechanical strength was studied. It has been determined that achievement of the optimal characteristics requires using a single-stage process (“stack – fiber”) instead of the more common two-stage process (“stack – cane – fiber”). In that case the attenuation level is 2-3 dB/km at the wavelength λ = 1550 nm and the tensile strength is about 5.5 GPa, which is comparable with the same parameters of specialty single-mode fibers made of solid media.
- Keywords: microstructured fiber, large core, single-mode regime, attenuation, mechanical strength
- Gordeychuk А., Dvornikov S., Ivanof V., Rusinov М., Semisoshenko M.
Evaluation of Radiocommunication Lines Interference in Mode with Slow Software Switching of the Running Frequency
- Abstract: The results of the estimation of noise immunity of radio communication lines in the mode with slow programmable adjustment of the working frequency are presented. A probabilistic model of radio-suppression of radio-communication lines of the HF-range by means of aiming interference is considered. The conditions providing for their temporary concealment and noise immunity are determined.
- Keywords: the slow-hopper mode, the setting of impact interference, radio link suppression model
- Kanaev A., Oparin E.
Proposals for Intellectual System Construction of Support of Decision-Making Management of Network Synchronization
- Abstract: The article has developed approaches to the formation of an intelligent decision support system for managing the network synchronization in the context of the mutual influence of the performance indicators of the telecommunications system and this network, allowing the development of timely and justified management decisions. As part of the formation of the structure of the intellectual system, a knowledge base model has been developed that ensures the necessary completeness of accounting for elements, states, parameters and relationships in the network. To develop strategies for managing the network, a methodology has been developed to formulate solutions, characterized by the joint application of the stages of classifying the state of the network through targeted search and the rational choice of action plans on a variety of alternatives. According to the "manager-agent" concept, the structure and composition of the control information database of the MIB of the network equipment are formed to solve the tasks of collecting, storing and issuing diagnostic information. An algorithm has been developed for calculating bandwidth reserve requirements for the transmission of monitoring and control information for a network synchronization.
- Keywords: knowledge base, stream structure, network synchronization, control system, telecommunication system
- Kireev A., Fokin G.
Accuracy Evaluation of Local Positioning by Radiomap Building and Inertial Navigation System
- Abstract: Article is devoted to the proposed method for constructing radiomaps of received Wi-Fi signal levels and inertial navigation signals from the built-in sensors of microelectromechanical devices. Experimental estimation of the positioning accuracy of the mobile device indoors using radio levels of the received levels and built-in inertial navigation systems is performed. The experiment was conducted in the expanded Wi-Fi network of SPbGUT and showed the possibility of increasing the positioning accuracy by 15% in case of combining Wi-Fi signal and inertial navigation in comparison with the known method of radiomap building.
- Keywords: positioning, simulation modelling, radiomap, inertial navigation system
- Kovalgin Y., Santos V.
Results of Experimental Research of Digital Radio Broascasting Characteris¬tics in DRM Format in the World
- Abstract: The results of experimental radio broadcasting in the DRM format in the world published by the national administrations of the countries in the reports and recommendations of ITU-R, are summarized. On the basis of their analysis, the conditions necessary for comfortable listening to sound programs, as well as the equipment requirements necessary to fulfill this condition are formulated. A list of software recommended for the use in frequency planning of digital broadcasting networks is presented.
- Keywords: digital broadcasting, DRM format, LF, MF, HF ranges, results of experimental research
- Makarov L., Protasenya S.
Computational Estimation Traffic of Telecommunication Network in Conditions of the High Uncertainty of Semantic Signs Detection
- Abstract: The article considers the problem of rapid formation of the image of the stream of events, in particular, for the purposes of traffic of a telecommunication network, in conditions of high uncertainty of detection of semantic features. The considered problem is proposed to solve by means of simulation through a synthesis of fractal images reproduced in real time on the basis of a dataset of dynamic event flow.
- Keywords: computer simulation, fractal signal design
- Novikov S.
The Approach to Modeling of a Large-Dimension Network Functioning in Conditions of External Destructive Effects
- Abstract: When analyzing routing methods on communication networks of arbitrary structure that have several dozen switching nodes, problems arise related to solving large-scale problems. This article proposes an approach that allows analysis of routing methods to identify those methods that will most effectively function in the intended communication networks and in specified conditions.
- Keywords: information distribution plan, routing method, external destructive effects
- Rogozinsky G.
Multi-Domain Approach and Models of Cyber-Physical Objects in Information Representation Systems
- Abstract: The usage of information representation methods in cyber-physical systems features several problems due to a large amount of data and informational overload. One possible solution is the polymodal representation of the information. The paper reviews a generalized approach to the cyber-physical systems, which is based on multi-domain model and several models in cyber-physical space.
- Keywords: multi-domain model, cyber-physical systems, complex systems, information representation systems
- Ryzhkov A.
NB–IoT Technology in Progress
- Abstract: On the basis of LTE specifications (Releases 13–15) NB–IoT technology physical level channels and signals are considered, including synchronization signals and preamble for random access procedure. Transport block formats are presented, differences in downlink and uplink traffic channel structures are discussed. NB–IoT traffic channel throughtput is estimatied.
- Keywords: NB–IoT, physical level, traffic, transport block, channel throughtput