Items of № 5, 2009

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

Advanced radio-frequency spectrum management methods


Last year’s concepts of liberalization is getting into all spheres of activities. It is also applicable to spectrum management system. Most experts say about necessity of creation of the open and flexible structure of spectrum management system that will develop new technical, social and economic benefits due to more liberalized approach in spectrum access. The way of liberalization is working out of alternative spectrum management methods. In given article the alternative spectrum management method by interference management is considered. Authors characterize various aspects of interference management with the purpose to answer to the main question: whether it is possible to use a spectrum more effectively than to apply spectrum management methods which regulate interferences, instead of transmitters' parameters regulation?

Key words: spectrum management, liberalization, radio-frequency spectrum, spectral efficiency, spectrum allocation, radio emissions, interference level, transmitter power, antenna orientation, interference conditions, current spectrum utilization, spectrum conversion, concept WAPECS, spectrum saving.

VHF/UHF spectrum monitoring networks planning and optimization


The article concerns optimum planning of new spectrum monitoring networks in the VHF/UHF frequency range and improvement of existing network performances. Criteria are specified in relation to calculation of cover zones by listening, measurement of emission parameters and direction finding with reference to monitored transmitters of three categories on an indicator «power — antenna height». The example is given on planning of a local network containing three monitoring stations in two various configurations with the analysis of calculation results concerning distributions of location uncertainty throughout the overall location coverage zone. Result of calculations are presented concerning parameters of big spectrum monitoring networks close to the theoretical regular ones with reference to the same categories of monitored transmitters, at various distances between monitoring stations.

Key words: spectrum monitoring networks, monitoring network planning, monitoring network optimization, direction finding, location by triangulation, location uncertainty, location uncertainty templates.

VSAT in Russia and overseas: comparative analysis of the standards and requirements


Comparative analysis of the standards and requirements for VSAT-stations in Russia and overseas is given in accordance with the normative documents of the international regulatory bodies.

In-orbit infrastructure for high-latitude and polar regions communication


The article introduces the results of research aimed at determining the number of satellites in a communication system on high-elliptic orbits. A definition of maintenance area for a communication system based on high-elliptic orbit satellites is offered. The authors also suggest function quality evaluation criteria for a number of competitive variants of orbital layout of communication system, as well as simple criteria for chosing the preferable one among them. The maintenance areas communication system are described for the orbits of Molniya and Tundra types.

Russian aeronautical communication’s technical modernization concept


Modernization the existing of aeronautical telecommunications network and data transfer of civil aviation of the Russian Federation in view of CNS/ATM International Civil Aviation Organization established by the Government of the Russian Federation dated 01.09.2008, № 652 «On approval of the federal target program «Modernization of the Unified System of Air Traffic Management of the Russian Federation (2009−2015 years)». Aeronautical Telecommunication Development Strategy provides the basis for the overall planning system within the air traffic management and indicates the direction in which to improve service connected within the next 15−20 years, as well as to further improve the use of spectrum for communication «Aircraft — Earth».

Key words: Aeronautical Telecommunications Network (ATN), data line, Air Traffic Control and its Air Traffic Management, unified system of Air Traffic Management, airspace and aircraft (ACFT) or A/C, channel line, communication services.

State and development prospects for aeronautical digital telecommunications in Europe


Programs of introduction of aviation data link in the Western Europe are considered. Economic benefit of their use in the European region is analyzed.

Principles of infrastructure plotting for the Russian ATN system in transit


In article questions of realization functions of concept CNS/ATM according to the international documents and reports and in view of world experience of creation of an infrastructure of network ATN are considered. Now determination of principles of construction of Russian network ATN of a transition period, development and creation of the systems providing the organization by information exchange in communication channels «air-ground-air» as in mode ACARS, and VDL 2 is the most actual. The infrastructure of network ATN of a transition period offered in article} determines shape of the fundamental components of system — ATN a router and the integrated terrestrial complex of a data transmission INCOD which will allow to service all information stream existing on today in modes ACARS and VDL2 VHF a range and as streams ACARS on satellite and HF to channels.

Assessing aeronautical digital communication channels' carrying capacity


The numerical method of capacity estimation for a communication channel with multiple position phase shift keying and its realization example is given. Asymptotic dependence of capacity channel and the optimal number of carrier initial phase positions from a signal/noise ratio are determined. Comparison of the obtained results and Shannon’s formula is also discussed.

Key words: aviation telecommunication, discrete information source, amount of a information, multiple position phase shift keying, capacity of a communication channel, Shannon’s formula, digital communication channel.

Use of multiway signals in airborne communication systems


The question of rational use is considered is frequency-power resources in onboard systems of aviation telecommunication at the expense of application of various multiposition systems of signals and the estimation of their efficiency is made. The capability of optimisation of ratio between speed of the transfer, necessary reliability of reception and used frequency band is shown.

Key words: frequency-power resources, multiposition communication systems, orthogonal and biorthogonal signals, coherent and non-coherent reception, conditional frequency band, average probability of an error.

Unmanned aircraft complex beam antenna control system


The problems of using the pencil-beam antenna systems in complexes of management of remotely piloted vehicles (RPV) are considered in this article. The offered control system of pencil-beam antenna system provides optimization the process of establishment of communication in any point of a trajectory of RPV’s flight. The offered control system supplies the opportunity of restoration of communication in case of its loss.

Analysing a broad-band amplifier’s operation under unmatched load


Techniques for calculation of power and efficiency of various wideband amplifiers operation in the presence of mismatched load are presented.

Key words: wideband amplifiers, matching, efficiency, traveling wave coefficient (TWC).

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