Thuraya
| Thuraya Satellite Telecommunications
|
|
|---|---|
 |
|
| legal form | Corporation |
| founding | 1997 |
| Seat |
Abu Dhabi and Dubai , UAE
|
| management | Samer Halawi |
| Branch | telecommunications |
| Website | www.thuraya.com |
The Thuraya Satellite Telecommunications Company is a telecommunications company that the satellite communications network Thuraya operates. The name comes from Arabic الثريا ath-Thurayya ,DMG aṯ-Ṯurayā and denotes the seven stars, thePleiades. Thesatellite constellationworks with threegeosynchronous satellitesand can therefore only be used in certain regions.
Companies
Thuraya is headquartered in Abu Dhabi and headquartered in Dubai in the United Arab Emirates . The gateway for feeding the signals into the company's own satellites is located in Sharjah . The company was founded on April 15, 1997. The shareholders include telecommunications companies from the Arab world (such as Etisalat and Arabsat ) and investment companies (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 coverage area of the geosynchronous satellites is divided into several spot beams. The assignment to the correct spot beam is based on the phone's GPS position. When a call comes in, the telephone is first alerted on a powerful “Sat-Alert” channel, and the user then moves to a zone with a clear view of the satellite (in Europe mostly to the south-east). The phone now registers itself on the spot beam, frequency and time slot assigned to the GPS position. The coverage zones can be shifted by changing the spot beam configuration. After the commissioning of Thuraya 2, which covers parts of Asia, the coverage zone in Africa was improved by reconfiguring the spot beams on Thuraya 1. The third Thuraya satellite has been in operation since summer 2008 and covers Asia to Japan, Oceania and Australia.
Reception is available in the following areas:
- Europe
- North, East and Central Africa
- middle East
- Asia
- Australia
Satellites
The Thuraya satellites were launched in geosynchronous transfer orbits with the aim of positioning them in geosynchronous orbits with an inclination of 6.2 ° or 6.3 ° to the equator at an altitude of about 36,000 km. The satellites were manufactured by Boeing (Hughes) and, with a launch weight of more than 5.1 tons, are among the heaviest communications satellites in the world. They were launched with Zenit 3SL rockets.
The antenna has a diameter of 12 meters. Due to the size of the antenna and a strong transmission power as well as a high reception sensitivity, the cell phones can be relatively small. A directional antenna with a narrow opening angle as in the Inmarsat network is not necessary. The antenna only needs to be pointed towards the satellite.
Like several early Boeing series 702 satellites, Thuraya 1 was affected by an unexpected aging of the reflectors, which are attached to the side of the solar cell arms of these satellites and which increase their performance. Therefore, less and less power was available for the satellite. Instead of these reflectors, Thuraya 2 and 3 are again equipped with larger conventional solar cell arms. Thuraya 1 has since been decommissioned and is in a cemetery orbit .
The ground station for the Thuraya network launched in 2001 is located in Sharjah .
| satellite | position | Start date ( UTC ) | Earth in orbit | Takeoff mass | Launcher | Video of the launch |
|---|---|---|---|---|---|---|
| Thuraya 1 | 98 ° 24'E, cemetery orbit since May 2007 |
October 21, 2000, 5:51 am | 3,200 kg | 5,100 kg | Zenit-3SL | |
| Thuraya 2 | 44 ° 04'E | June 10, 2003, 1:55 pm | 3,200 kg | 5,200 kg | Zenit-3SL | |
| Thuraya 3 | 98 ° 30 'E. | January 15, 2008, 11:49 am | 3,200 kg | 5,173 kg | Zenit-3SL | sea-launch.com |
Since the satellites are not on a geostationary but only on a geosynchronous orbit around the earth, their apparent location in the sky is not fixed, but varies slightly over the course of the day. At the Bern location, for example, the sky position of Thuraya 2 fluctuates between 132 ° and 136 ° southeast during the day and the elevation angle varies from 22 ° to 28 °.
The start of Thuraya 3, which was actually scheduled for January 2007, was postponed due to a false start on the Sea Launch satellite launch platform and could only be rescheduled on January 15, 2008.
technology
Thuraya uses the following frequency ranges:
- Satellite to subscriber: 1525.0–1559.0 MHz
- Subscriber to satellite: 1626.5-1660.5 MHz
- Satellite to ground station: 3400.0-3625.0 MHz
- Ground station to satellite: 6425.0-6725.0 MHz
For calls from Thuraya satellite telephone to Thuraya satellite telephone, the voice channel is switched directly via the satellite. The ground station is only required to switch the call. The voice channel is only handled via the ground station in Sharjah for calls from the landline network or in the landline network as well as between telephones that are booked on different Thuraya satellites.
The ITU assigned the area code +882 16 to Thuraya network. The network identifier assigned by the ITU is 901-06.
Due to bilateral roaming agreements with over 300 GSM network operators, Thuraya cell phones can also be used with standard GSM SIM cards. In addition, Thuraya mobile phones have a GPS receiver with which the position can be determined precisely. Since Thuraya uses a protocol derived from GSM on the air interface to the satellite, this system is very similar to normal GSM use, only with a little more delay. As in GSM networks, the data service offered is GPRS with up to 60 kbit / s in the downstream and up to 15 kbit / s in the upstream (GmPRS).
Products
The following services are possible in the Thuraya network:
- Voice communication
- Short Message Service (SMS)
- Data connection 9600 bit / s
- fax
- Free SMS from the Internet to the Thuraya mobile phone
- GMPRS / Wap and Internet Services similar to GPRS
- Sending the current GPS position via SMS
- ThurayaIP - mobile data transmission up to 444 Kbps
- ThurayaRecharge - direct top-up of prepaid credit possible via telephone and PIN
Recently, Thuraya has also been offering complete solution packages for aircraft, ocean-going ships and for the management of vehicle fleets, as well as numerous value-added services, among others. a. also in collaboration with the news channel Al Jazeera from Qatar.
Web links
- Company website (English)
- Thuraya 1 , Thuraya 2, 3 - pages of the satellite manufacturer Boeing (archived 2012)
- Thuraya network coverage 2016
Individual evidence
- ↑ Sea Launch Mission page - Thuraya-1 ( Memento from October 12, 2009 in the Internet Archive )
- ↑ Sea Launch Mission page - Thuraya-2 ( Memento from October 12, 2009 in the Internet Archive )
- ↑ Sea Launch Mission page - Thuraya-3 ( Memento from October 12, 2009 in the Internet Archive )
- ↑ List of ITU-T Recommendation E.164 Assigned Country Codes. (PDF; 19 kB) April 15, 2009, archived from the original on April 1, 2010 ; accessed on December 2, 2009 .
- ↑ Status of reserved or assigned E.212 shared Mobile Country Codes (MCC) and associated Mobile Network Codes (MNC) ( English , PDF; 15 kB) Retrieved on December 2, 2009.
- ↑ Thuraya advertising brochure ( Memento from November 22, 2009 in the Internet Archive ) (PDF)
- ↑ sms.thuraya.com
- ↑ thuraya.de
- ↑ thuraya.de
- ↑ thurayarecharge.com