Africa set for improved satellite coverage from Alphasat
Africa will get improved satellite coverage when Astrium's Alphasat is launched from French Guiana later this year - the programme has reached a major milestone this week with the successful completion of the major testing stage of the 1-XL programme.
Astrium has been undertaking thermal vacuum testing for the past three months to simulate the harsh conditions in space. To replicate the severe cold faced when the satellite passes from direct sunlight into the Earth’s shadow, the shroud of the testing chamber was pumped full of liquid nitrogen to lower the temperature to -173 deg C.
At other times the temperature was raised to hundreds of degrees Celsius, all in a near vacuum representing just 100 millionths of the atmospheric pressure found on the ground.
Alphasat is a high-power telecom satellite built by Astrium, through a public-private partnership between ESA and UK satellite operator Inmarsat.
Weighing more than 6,600 kg, it is based on the new European Alphabus telecommunications platform developed by Astrium and Thales Alenia Space under joint contract from ESA and the French space agency, CNES.
Alphasat I-XL carries a new generation of advanced mobile communications payloads as well as four technological demonstration payloads for ESA. These include a space-to-ground laser communications system and a new type of star tracker.
Alphabus is a larger telecom payload designed for direct-to-home TV broadcasting, digital audio broadcasting, broadband access and mobile services.
Inmarsat currently offers its BGAN (Broadband Global Area Network) family of services for the aeronautical, land and maritime markets via its three Inmarsat-4 satellites.
The Alphasat mission will extend Inmarsat's current L-band BGAN services, providing an additional 7 MHz of spectrum over Europe, the Middle East, Africa and parts of Asia, from its 25 degree East geostationary orbital position.
It will also allow Inmarsat to progress its goal of having aviation safety services certified on its 432kbps SwiftBroadband service for aircraft, providing satellite-based ACARS datalink, prioritised IP data and voice channels.
Alphasat's launch is planned for this summer aboard an Ariane 5 from Europe's Spaceport in French Guiana.