The Eutelsat W1 satellite undergoes testing. Photo: Eutelsat

The W1 satellite was built by Astrium SAS of Toulouse, France, and is one of four in the European Telecommunications Satellite Organization's W-series of spacecraft.

The satellite design is compatible with the Ariane 4/5 family launched from Kourou, the Atlas 2 series launched from Cape Canaveral and Proton launched from Baikonur.

W1 is based on the three-axis stabilized EUROSTAR 2000 PLUS platform. The craft's side mounted communications antennas are 2.5 m diameter, which provide the fixed transmit and receive coverages, are of compact geometry Gregorian design with shaped main reflectors. As mentioned previously, the top-mounted transmit/receive steerable antenna may be steered anywhere over the visible earth and the elliptical footprint may be rotated by up to ±90 degrees. This antenna has a shaped main reflector and a shaped sub-reflector and it is supplied by Alenia Aerospazio of Italy.

The satellite is modular in concept with the service module housing the platform subsystems including the propellant and pressurant tanks, the latter located in the main load-bearing central cylinder. The North/South walls and the earth facing panels constitute the communications module and accommodate the repeater equipment.

W1 facts
Spacecraft	EUROSTAR 2000+
Life	minimum 12 yrs
Orbital Slot	10 degrees East
Dimensions (in meters)	31.7 x 8 x 4.8
Weights	Launch: 3,250 kg Dry: 1,430 kg
Satellite Power	2 solar wings 4 panels each 7 kW end of life
Payload transponders	28 Ku-band
Source: Eutelsat

This new addition to Eutelsat's system will be positioned in geostationary orbit at 10 degrees East where it will be used for a range of applications that include business communications, Internet-based services and television distribution and contribution links.

Equipped with 28 Ku-band transponders, W1 has two coverage zones: a Widebeam stretching over Europe, North Africa and the Middle East and a powerful Steerable Spotbeam that will support Eutelsat's expansion into new geographical regions. Up to 20 transponders can be connected to the Widebeam and up to 12 to the Steerable Spotbeam.

Following the launch of W1, Eutelsat's satellite resource will consist of 18 Ku-band satellites. Positioned in the orbital arc from 12.5 degrees West to 48 degrees East they provide reach of Europe, Africa, large parts of Asia and connectivity with the Americas. Five new satellites are in construction and due for launch by first quarter 2002.