ESA and Inmarsat
Prepare for Alphasat
(20 June 2007) Today at the Paris Air
Show, ESA and Inmarsat moved closer to the implementation of Alphasat, the
first satellite based on Alphabus, the new European telecommunications
platform.
Alphabus is a programme initiated by ESA and CNES to
jointly develop a product through a project industrial team made of EADS
Astrium and Thales Alenia Space. It is a new multi-purpose platform for the
high-power payload communications satellite market.
Alphasat will be the
satellite using the Alphabus proto-flight platform, achieving in-orbit
validation of the platform through a commercial operator.
At Le Bourget,
ESA and Inmarsat announced the signature of a Memorandum of Understanding
(MoU), which is a step towards confirming Inmarsat as the first customer for
the Alphabus platform.
Inmarsat intends to fly an extended L-band
payload, in parallel to and supporting its existing world-leading global mobile
satellite services. This Inmarsat mission definition is based around multimedia
mobile services already provided by the current Inmarsat IV satellites through
Broadband Global Area Network (BGAN)
The satellite will be positioned at
25 degrees east, with its coverage centred over Africa and providing additional
coverage to Europe, the Middle-East and parts of Asia.
Artist's impression of Alphasat configured for the Inmarsat XL mission (courtesy: ESA - J. Huart)
Implementation of this Geo-mobile
application will use the Alphabus platform design in a configuration that
requires a 90 degree change to the satellite flight orientation to improve
accommodation of the feed/reflector configuration and allow the embarkation of
a large deployable reflector. Both of these capabilities will be offered as
options in the Alphabus portfolio.
In addition, Alphasat will embark
three ESA-provided technology demonstration payloads: an advanced star tracker
using active pixel technology, an optical laser terminal for geostationary to
low-Earth orbit communication at high data rates, and a dedicated payload for
the characterisation of transmission performance in the Q-V band in preparation
for possible commercial exploitation of these frequencies.
The Alphasat
programme meets the diverse but mutually compatible goals of all the parties,
such as the first flight and in-orbit verification of Alphabus and the
implementation of an advanced L-band operational payload, which will supplement
the existing Inmarsat satellite constellation and offer the opportunity for new
and advanced services.
Negotiations to conclude the contract are
continuing and are intended to allow the commencement of the Alphasat programme
by the third quarter of 2007 with a launch targeted by 2011.
(source:
ESA)