The Decisions from "Broadcast Arsenal"
By Alexander Zenin

In the mid 90s on the analogous television deathbed came the digital television based on the MPEG-2 standard (the video compression standard) that allowed to transmit the quality image and sound at the high rate of compression. In the one standard stem of the satellite relay using MPEG-2 there might be distributed 4...6 of TV programs.

In Russia the first introduction of the digital methods of transmission of the television signals through the artificial satellite of the Earth began just few years ago. The Altai Territory became the first region where the distribution of TV programs is going through the connection satellite. The winner of the tender for the supply of equipment and the building of the distributive network of the TV broadcasting became the Microtech Company that is a member of the group of companies "Broadcast Arsenal".

As the satellite relay for the distribution of the TV signal around the Altai Territory the artificial satellite NSS-703 was chosen from the station point of 57° EL. The relatively high effective isotropic radiated power from the artificial satellite (about 47dBW) allows using around the whole territory antennas of 2.4 m in diameter made by the Andrew Company and the output transmitter of 25 watt power SEE Technologies, the equipment of the digital compression of the TV signal of the Phillips company.

At present stage the accordance of one any service in the field of the telecommunications doesn't satisfy the increased demands of the majority of clients. The creation of the complex network that includes the distribution network of the digital satellite television and the on-line network of the access to the Internet is the task that the winner of the tender of "The Networks of the Satellite Communications of the Bashkortostan Republic", group of companies "Broadcast Arsenal" was faced with.

Scheme of Bashkortostan Republic satellite telecommunication network

Starting from the problem put by, the specialists of the company offered an idea of the creation of the single digital platform with the use of the VSAT technologies as one of the component of the network. The idea of creation of such a complex (multiservice) network in Russia in now only on the stage of projecting (the project is developed for the Far-Eastern Federal Territory).

The suggestion of the company was based on the use as the satellite relay the artificial satellite Intelsat-604 in the orbital position of 60° EL with the planned change in the first quarter of 2002 of the satellite of the new series Intelsat-904. The very high effective isotropic radiated power from the artificial satellite Intelsat-904 (over 53 dBW in the middle of the area) allowed using for the professional antenna's registration of relatively small diameter (1.8m) as for the distribution TV network as for the network of the Internet access.

On the central loading station situated in the Ufa City the equipment of the digital compression Tanbderg was set. The registration stations of the digital TV are accomplished with the AlMet Company antennas, the converters and the exciter of Swedish Microwave, decoders of Scopus Network Technologies. The conducted tests had shown that completed with such an equipment stations have the reserve at the receiving about 6 dB approximately on all of the Bashkortostan Republic.

The VSAT technology SkyStar Advantage for the organization of the data transfer, uniting of the local calculating networks, high-speed access to the Internet etc was offered. The developer and the producer of VSAT technology are the Israel company Gilat Satellite Networks Ltd.

The peculiarity of the SkyStar Advantage technology is that on the base of single platform few different developments are united. The same network can be used for the on-line data, speech and paging transfer and for the broadcast of multimedia products through IP, transfer of simplex multiplexed flows, support of the MPEG-1 and MPEG-2 video standards.

In the base of operating of the SkyStar Advantage equipment the principle of the plural access with the time-and-frequency division (FTDMA). This is the two-dimensional access system that allows providing the lack of time losses on the repeated transfers and rational using of the streaks of frequency for all the service stations in the network, coping with momentary peaks of traffic in the VSAT network without the substantial delay in the answer time. The network is insensitive to the short-term fail of the contact that is caused by the interference of the frequency.

For the configuration of the monitoring of the network the control systems NMS that are established on the central loading station are used. NMS is fulfilled in the form of combination of hard- and software. It caries the functions of automated distribution of the resource between users, monitoring of the condition and control of service stations. With the help of the NMS it is always possible to control the current status and to appraise the statistics of the network operation.

All the connections in the network are fulfilled during one relaying of the signal through the artificial satellite. The joint doesn't have the transit stations. The necessary for the set of the connection satellite resource is used only during the connection and livens up by the standard typing of the subscriber's number or by the stirring up of the traffic. Each port in the network has the unique telephone number or a mask.

Scheme base configuration SkyStar Advantage network

The SkyStar Advantage network consists of the central unit, satellite channel and the remote VSAT. The unit consists of the radio frequency terminal (RFT) and the modulation equipment. The latter includes the central satellite processor (HSP) for the control of the satellite connection, the central protocol processor (HPP) for the conduction of the interface with the equipment of the data transfer, optional speech processor (HVP) for the speech interfaces and the network monitoring system (NMS).

The standard subscriber's station consists of the external equipment, that is usually situated on the roof of the building or nearby on earth and the channeling connection as ATS, server or router.

Unlike other VSAT systems the central loading station (HUB) is characterized by the internal communication in the unit for the connection of the remote terminals between each other.

To SkyStar Advantage the modular flexibility is peculiar. The internal facility has three housings for the build-in boards. Such a construction allows diversifying the facility on the spot adding as into PC the build-in boards there can be got the support of the numerous interfaces and applications.

In the table below the technical parameters are brought that fully characterize the technology and the SkyStar equipment as the most up-to-date technology of the satellite connection that is ideal for the building of large corporate networks.

The architecture of the system "The network of the satellite telecommunications of Bashkortostan" is performed in the "star" scheme. Without the use of the substantial investments of capital but just with establishing by one additional piggyback board to the central station and to the VSAT terminal all the network might be converted into the fully connected and operate on the principle "each one with each one".

All the land-based TV equipment (including the TV transmitter and antennas' facilities) are made on the own enterprise and have the wide range of facilities 1 W...5 kW.

The group of companies "Broadcast Arsenal".

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