Thuraya

The Thuraya Satellite Telecommunications Company is a telecommunications company that operates the satellite communications network Thuraya. The name comes from Arabic الثريا ath - Thurayya, DMG AT Turaya and called the Seven Sisters, the Pleiades. The satellite constellation uses three geosynchronous satellites and can therefore be used only in certain regions.

Business

The company Thuraya is headquartered in Abu Dhabi and the main office in Dubai in the United Arab Emirates. The gateway to feed the signals into the company's own satellite is located in Sharjah. The company was founded on 15 April 1997. Among the shareholders are telecommunications companies in the Arab world (such as Etisalat and Arabsat ) and investment firms (such as the Abu Dhabi Investment Company and Dubai Investments ), but also the T- Systems subsidiary DETECON.

Coverage area

A special feature of Thuraya is that the illumination area of the geosynchronous satellite is divided into multiple spot beams. The assignment to the correct spot beam is effected on the basis of the GPS position of the phone. On a transmission power strong " satellite Alert " channel the phone when a call is first alerted the user then moves into a zone with a clear view to the satellite ( in Europe mostly to the southeast ). Now, the phone registers to the corresponding GPS position assigned spot beam, frequency and time slot. Coverage zones can be moved by changes in the spot beam configuration. So the parts of Asia, after the commissioning of Thuraya 2, covers, cover zone in Africa improved by reconfiguration of the spot beams on Thuraya 1. The third Thuraya satellite is since summer 2008 and covers Asia to Japan, Australia and Oceania from.

Reception you have in the following areas:

  • Europe
  • North, East and Central Africa
  • Asia
  • Australia

Satellite

The Thuraya satellite were positioned in a geosynchronous orbit at 6.2 ° or 6.3 ° inclination to the equator, at about 36,000 km altitude. The satellites were manufactured by Boeing ( Hughes ) and count with a takeoff weight of more than 5.1 tons of the heaviest communication satellite world. Started they were with Zenit- 3SL ( Sea Launch ) missiles. The antenna has a diameter of 12 meters. Due to the size of the antenna and a strong transmission power and high receive sensitivity, the phones can be relatively small. A directional antenna with a small angle, as in the INMARSAT network is not necessary. The antenna only needs to be aligned in the direction of the satellite.

Thuraya 1 was like several early satellites of the Boeing 702 series affected by an unexpected aging of the reflectors that are mounted on the side of the solar cells booms of these satellites and increase their performance. Therefore, stood for the satellite increasingly less power. Thuraya 2 and 3 are again fitted in place of these reflectors with larger conventional solar cells booms. Thuraya 1 has since been decommissioned and is located in the graveyard orbit.

The ground station for the Thuraya network started in 2001, is located in Sharjah.

Clock to 05:51:59 ( UTC)

Clock to 13:55:59 ( UTC)

At 11:49 clock ( UTC)

Since the satellites are not in geostationary, but only in a geosynchronous orbit around the earth, is its apparent location in the sky is not fixed, but varies slightly throughout the day. At the site Bern example varies the sky position of Thuraya 2 during the day between 132 ° and 136 ° Southeast and the elevation angle varies from 22 ° to 28 °.

The rate applied is actually for January 2007 launch of Thuraya 3 has been moved to the satellite launch platform of Sea Launch due to a false start and could be made up until 15 January 2008.

Technology

Thuraya uses the following frequency ranges:

  • Satellite to subscriber: 1525.0 to 1559.0 MHz
  • Participants to satellite: 1626.5 to 1660.5 MHz
  • Satellite to ground station: 3400.0 to 3625.0 MHz
  • Earth station to satellite: 6425.0 to 6725.0 MHz

In discussions of Thuraya satellite phone Thuraya satellite phone, the voice channel is mediated directly through the satellite. The ground station is only required for the mediation of the conversation. Only for calls from the fixed network or the fixed network and between phones that are posted on various Thuraya satellite, the voice channel over the ground station in Sharjah is settled.

From the ITU the Thuraya network has been allocated the prefix 882 16. The assigned by the ITU network identifier is 901-06.

Because of bilateral roaming agreements with over 300 GSM operators Thuraya phones can also be used with standard GSM SIM cards.

In addition, Thuraya phones have a GPS receiver, the position can be accurately determined.

Since Thuraya on the air interface uses a derivative of GSM Protocol to the satellites, this system is very similar to the normal GSM usage, only with a little more delay. As in GSM networks is as GPRS data service of up to 60 kbit / s downstream and up to 15 kbit / s offered in the upstream ( GmPRS ).

Products

The following services are available in the Thuraya network:

  • Voice communication
  • Short Message Service ( SMS)
  • Data connection to 9600 bit / s
  • Fax
  • SMS for free from the Internet to the Thuraya phone
  • GmPRS / Wap and internet services like GPRS
  • Send the current GPS location via SMS
  • ThurayaIP - mobile data transmission up to 444 Kbps

Recently, Thuraya offers also complete solution packages for aircraft, ocean-going vessels and for the management of vehicle fleets, as well as numerous " value added services ", including in cooperation with the news channel Al Jazeera from Qatar.

Types of business entity DIN 31635 Emirates Telecommunications Corporation Near East Zenit (rocket family) Transmitter power output International Telecommunication Union Globalstar Orbcomm
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