Items of № 12, 2012

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


System informatization’s development in agriculture

The research tells us analysis of state and development of infocommunication system and technology country agriculture organization. Also it`s said the importance of using informatization in agricultural production as a basis for conversation to innovation way of development. Author have found reason why adopts slowly information technology and basic condition of computerization. They also point out the necessity of approval the industry program of comprehensive investigation and system development of informational support for agricultural organization witch allows to solve the task which supply users of informational services. It`s shown expected amount of adoption in information system during 2013−2020 years.
Key words: informatization, innovation project, infocommunication system and technology, research of information system, methodology of improving operating control.


IP-packets' flow characteristics on the output of the switching nodes in the next generation network

This artile presents the study results of the output process of the switching node in a next generation network. A peculiarity of such node lies in the fact that the time processing of IP packets can be considered as constant magnitude. This allows estimate one of the most important characteristics if the coefficient of variation of the investigated random variable. Obtained results allow study of real processes of IP-packets service in the next generation network.
Key words: traffic, simulation model, teletraffic system, output flow, coefficient of variation.


Technique of availability level’s quantitative estimation of the mobile communication networ

The method of an assessment of the quality (QoS), combining a verbal estimates is considered from the user and the quantitative analysis of quality of service of a flow of the demands arising at access to a network of mobile communication. The method of a quantitative assessment of a level of quality of access and algorithm of the decision with use of hierarchical model of key executed indicators of quality of KPI is offered. In article numerical results of an assessment of the integrated quality of providing access to the mobile center of switching (MCS) are presented. Key words: QoS, hierarchical model, KPI, MCS.


Estimation of communication channel parameters

A technique of determination of the conditions of implementation of a communication channel capacity for given values of the frequency band, occupied by a signal, and the signal-to-noise ratio (SNR), is proposed.
Key words: channel capacity, frequency band, signal-to-noise ratio (SNR).


Maintenance modelling of fiber optic transmission links' linearly-cable constructions using functional networks' method

The methods of simulation of fiber optical lines maintenance are represented. The simulation method based on functional networks was chosen and validated. The calculation of efficiency of maintenance parameters by the examples of three technology was carried out. The recommendations on application of the simulation method using functional networks was proposed.
Key words: optical fiber, optical cable, maintenance, fiber-optic link components, fiber-optic link.


Design procedure’s assessment of chromatic and polarizing mode dispersion’s compensation

Key words: optical fiber, chromatic and polarization mode dispersion, amplifier part, transmission system, modulation.


Application of nonlinear phase filters for noise stability increase of signals' reception in fiber optics transmission system

In article the way of processing of signals in fiber-optical system of the transfer is considered, allowing to raise a reception noise stability. It is based on use of the nonlinear phase filters realized at optical level, as the filter before-detector processing. The reception noise stability is estimated analytically by calculation of probability of erroneous reception with application of a method of characteristic functions. Results of the comparative analysis of offered algorithm of reception with algorithm one-readout reception are resulted. Possibility of realization of nonlinear phase filters is discussed with application of photon-crystal optical fibers with high nonlinear properties.
Key words: The nonlinear phase filter, digital processing of signals, a reception noise stability, characteristic function, photon-crystal optical fibers.


Broadband omnidirectional antenna arrays for radio communication with a filter division of sub-arrays

This article is about creating broadband (bandwidth up to 5 times) omnidirectional antennas for radio communication. Base idea of building such antennas based on two sub arrays (each for own subset of frequencies) separated by diplexing filter is discussed. Schematics of diplexing filter for a specific bandwidth is shown and main characteristics discussed. The problem of creating radiating elements of sub arrays is addressed. Variant with shunted self-complementary printed vibrators in dielectric cover is founded. Parameters of sub arrays (amount of vibrators on each floor, amount of floors) are calculated for various mast diameters and its vertical sizes. Specific variant of antenna is listed (for specific bandwidth and specific mast). Expected characteristics of this variant are listed. Key words: radio communication, antenna, two sub arrays.


Algorithm construction of difficult antenna complexes' electrodynamic analysis for EMS analysis using modern electrodynamic methods

Some problems of electromagnetic compatibility analysis of complex antenna systems are shown. For calculation of main electric characteristics of antenna systems modern hybrid electrodynamics methods are used. Some characteristics of electrodynamics analysis algorithm are shown. Some numerical results are given.
Key words: еlectromagnetic compatibility, complex antenna systems, hybrid methods.


Small-sized broadband HF-band transmitting antennas with dissipative impedance matching devices

This article is about problems of building small-sized broadband transmitting antennas. These antennas are of use in radio communication systems, using modern technologies of signal filtering that require wide range of frequencies. The latter excludes any chance of using adaptive impedance matching devices as they can only match impedance in a small frequency range. That said antennas with dissipative impedance matching devices are of interest.
Method used in research is described. It is based on electrodynamics modeling of emitting antenna structure using known method of Harrington integral-differential equation. Main equations for impedance, feeder travelling-wave factor, efficiency are listed.
Results of studying 7 variants of building small sized HF-band antenna are listed — travelling-wave factor and efficiency depending on frequency are shown. Variants differ mainly by their emitter structure. In every case it was based on vertical asymmetric vibrator and — to some extent — by scheme of dissipative impedance matching device.
To sum it up small-sized emitter structure makes it hard to reach the necessary matching level without severe impact on efficiency. Nevertheless analysis (including complexity, commutation etc) allowed finding optimal variant among listed.
Key words: small-sized broadband transmitting antenna, hf-band, impedance matching, dissipative impedance matching device.


Transmitting HF-band antenna arrays' construction

This article talks about problems of building transmitting HF-band antenna arrays. These usually are circular (circular antenna arrays — CAA) and thus allow scanning every azimuth and elevation.
Brief review of problem is given. Existing HF-band CAA are mentioned including latest ones, which are active and use LC-networks for beamforming (allows using every emitter for beamforming). Known active CAA are receive ones and the problem is whether we can design transmitting antennas the same way (active antennas using LC-networks).
Main ideas for building transmitting active CAA using LC-network are founded. Array schematic is given. Peculiarities of transmitting CAA are mentioned. Short description of CAA functioning is given. Short description of known technical solutions used is given (for example, LC-network).
Analysis of problems that has to be solved to build active HF-band CAA is given. Problems are divided into two groups. First group contains problems that could prevent active CAA from transmitting in general. Those are reduced to vibrator impedance matching inside active emitter. The second group consists of problems preventing several emitters operate simultaneously. Again these are vibrator impedance matching problem (in bandwidth of two or more emitters), emitters decoupling problem and the problem of suppressing non-linear effects when several signals pass the amplifier simultaneously.
From the review it is obvious that a problem of building active HF-band CAA is solvable in — at least — single signal variant (one emitter operating). At the same time it is unclear if several emitters could operate simultaneously.
Key words: active antenna, corcular antenna array, impedance matching, decoupling, beamforming network, lc-network.

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