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N° 3–1997: European satellite telecommunications technologies to improve maritime safety

23 January 1997

The European Space Agency has contributed to the development of a faster, more reliable and more accurate satellite distress system for ships at sea, in the framework of a project promoted by Inmarsat - the global mobile satellite operator.

Called Inmarsat-E (for Emergency), this search and rescue system uses dedicated L-band channels (at 1.6 GHz) on the existing Inmarsat telecommunications satellites in geostationary orbit. Inmarsat is committed to offer this service within the Global Maritime Distress and Safety System, being implemented by the International Maritime Organization (IMO). Use of the Inmarsat-E system will be free of charge.

The continuing high number of losses of ships at sea and the progress in satellite technology have prompted IMO to adopt regulations requiring most ships to carry emergency position indicating radio beacons (EPIRB), small transmitters (about 1 W in power) that a ship can trigger in an emergency. The signal is immediately received by the geostationary satellite and relayed down to a coast Earth station equipped with dedicated and very sensitive receivers to raise the alarm. The signal includes the identity of the ship, the type of alert and the ship's position evaluated from a GPS receiver built in the EPIRB (with an accuracy of 200 m). Within a few minutes of the alert being sent, these data reach a search and rescue center which begins rescue operations.

For the Inmarsat-E system, ESA has financed the development and the manufacturing of two sets of receivers (contracts were awarded to Nortel-DASA, Germany and Nokia, Finland), while the German Ministry of Transport purchased two other sets. Three receivers have been installed and are now operating in stations at Raisting (Germany), Niles Canyon (California) and Perth (Australia). The digital receiver in the Earth station -typically a compact rack - is designed for fully unattended operation. In a case of distress, almost immediately the land Earth station receives the alert message which is automatically transferred to the relevant search and rescue center.

The Inmarsat-E system will be inaugurated worldwide on Thursday, 30 January 1997. A press conference will be held at Inmarsat's Headquarters , 99 City Road, London EC 1AX. For accreditation to attend the press conference contact the Inmarsat Press Office, Kim Ladone, tel: + 44 171 728 1773, fax: + 44 171 728 1179.

For further information on ESA's contribution to the Inmarsat-E system, please contact the ESA Public Relations Office, tel: + 33 1 5369 7155, fax: + 33 1 5369 7690.