Thuraya
Thuraya is a mobile satellite communications operator established in 1997 and based in the United Arab Emirates (UAE) 1. It operates as a subsidiary of Yahsat and provides mobile satellite services across Europe, the Middle East, North, Central, and East Africa, Asia, and Australia. Thuraya's services are delivered using geostationary satellites operating across C-, Ku-, Ka-, and L-bands, supporting both FSS and MSS. Thuraya subscribers can roam onto hundreds of terrestrial GSM networks worldwide, and GSM users from those networks can similarly roam onto the Thuraya satellite network using compatible handsets.
Thuraya handsets typically transmit at powers of up to 2 W and use relatively high-gain antennas, requiring the user to point the handset toward the satellite, assisted by an integrated GPS receiver. The system is designed with a fade margin of approximately 10 dB to accommodate shadowing of mobile terminals. As the satellites operate in geostationary orbit, a noticeable propagation delay is present in voice communications. Thuraya services include voice telephony, SMS messaging, and packet data, with typical data rates of about 60 kbps on the downlink and 15 kbps on the uplink.
The satellites are technically similar, and each has two large solar-panels that generate 11 kW of power and two antenna systems: a 1.27-m C-band antenna; and a 12 x 16-m, 128-element L-band antenna providing 351 configurable spot beams: 34 MHz from 1.6265-1.6605 GHz for the uplink and 1.525-1.559 GHz for the downlink providing 1,087 31.25-kHz uplink and downlink QPSK FDMA/TDMA paired channels. The C-band gateway frequencies are 6.425-6.725 GHz (uplink) and 3.400-3.700 GHz (downlink).
Thuraya 1 had a launch mass of 5,250 kg and was launched on 21 October 2000 by Sea Launch. Unfortunately, the solar panels failed which meant that the satellite was used for testing and backup until May 2007, when it was moved to a disposal orbit. Thuraya 2 had a mass of 3,200 kg and was launched by Sea Launch on 10 June 2003 into GEO orbit at 44°E, inclined at 6.3°. After a number of false starts, Thuraya 3 was launched on 15 January 2008 by Sea Launch into GEO orbit at 98.5°E, inclined at 6.2°. On 15 April 2024, Thuraya 3 suffered an "unexpected payload anomaly" and coverage was not able to be restored to users in parts of the world, including Australia 2.
Thuraya-4 NGS was launched aboard a SpaceX Falcon 9 on 4 January 2025 after slipping from its original 2024 launch target. Built by Airbus Defence and Space on the Eurostar Neo platform, the approximately 5,000-kg all-electric satellite carries a large 12-m deployable L-band antenna and an advanced digital payload capable of dynamically routing up to 3,200 communication channels across numerous steerable spot beams. It is replacing the ageing Thuraya-2 satellite and provides mobile satellite communications services across Europe, Africa, the Middle East, and Central Asia. After launch, the spacecraft used electric propulsion to reach its operational geostationary orbit before entering commercial service.