Біріккен Араб Әмірліктерінің спутниктік байланыс жүйесі - Thuraya

UAE based satellite telecommunications company
the satellite communications system

Thuraya (الثريا, Gulf Arabic pron. : ; from the Arabic name for the constellation of the Pleiades, Thurayya) is a United Arab Emirates based regional mobile satellite service (MSS) provider. The company operates two geosynchronous satellites and provides telecommunications coverage in more than 161 countries in Europe, the Middle East, North, Central and East Africa, Asia and Australia. Thuraya's L band network delivers voice and data services. Thuraya is the mobile satellite services subsidiary of Yahsat, a global satellite operator based in the United Arab Emirates, fully owned by Mubadala Investment Company. The geostationary nature of the service implies high round trip times from satellite to earth leading to a noticeable lag being present during voice calls.

Thuraya's country calling code is +882 16, which is part of the ITU T International Networks numbering group. Thuraya is not part of the +881 country calling code numbering group as this is allocated by ITU T for networks in the Global Mobile Satellite System, of which Thuraya is not a part, being a regional rather than a global system.

Transceivers communicate directly with the satellites using an antenna of roughly the same length as the handset and have a maximum output power of 2 Watts. QPSK modulation is used for the air interface. Thuraya SIM cards will work in regular GSM telephones and ordinary GSM SIM cards can be used on the satellite network as long as the SIM provider has a roaming agreement with Thuraya. As with all geosynchronous voice services a noticeable lag is present while making a call. Due to the relatively high gain of the antennas contained within handsets, it is necessary to roughly aim the antenna at the satellite. As the handsets contain a GPS receiver it is possible to program the ground position of the satellites as waypoints to assist with aiming. The service operates on L band carriers assigned in blocks to areas of coverage referred to as "spotbeams", which are Thuraya's equivalent to cells or service areas. In L band, 34 MHz of bandwidth from 1.525 GHz to 1.559 GHz is assigned for downlink (space to earth) communication, while the uplink (earth to space) operates between 1.6265 GHz and 1.6605 GHz. Uplink and downlink channels are 1087 paired carrier frequencies, on a raster of 31.25 kHz. A Time Division Multiple Access (TDMA) time slot architecture is employed which allocates a carrier in timeslots of a fixed length.

Every Thuraya phone and standalone transceiver unit is fitted with a GPS receiver and transmits its location to the Thuraya gateway periodically. The built in GPS capability can be used for waypoint navigation.