The Inmarsat E+ System
the Inmarsat-E/E+ system has been shut down on 1.12.06 the description
for historical reference only.)
is an enhancement to the
Inmarsat-E system. Inmarsat-E+
raises the high redundancy of Inmarsat-E even further and
enables the installation of remote RCCs at low cost. Inmarsat-E+
also be used to deliver acknowledgement information to Inmarsat-E+
EPIRBS in the future. The navtec Ltd. did the design,
development and implementation of the world-wide infrastructure for
(so called acknowledgement channel). The system consists of the
(Run the mouse over the
- The EPIRB receives position information via GPS and
the distress call via Inmarsat satellites.
- Inmarsat satellites relay the distress call to the land
earth station (LES).
- The land earth station forwardes the distress call not only
via X.25 but also via satellite to the nearest rescue co-ordination
centre (RCC). This increases the reliability and raises the redundancy.
- The Inmarsat satellite relay the call to several receivers
All this takes place in seconds - fully automaticly without any time
delay. In real life there is more than one LES receiving the beacons
transmission as well as there are more than one RCCs receiving the
forwarded distress call.
- The Maritime Rescue Co-Ordination Centre (M)RCC receives
the call on a dedicated channel.
- The Inmarsat Headquater (NOC) receives the call.
- The beacon receives the call and may switch on a green
light to indicate to the person in distress that the call has been
The (M)RCC installation consists of a 19" rack with fully redundant
antennas, redundant receivers, redundant demodulators, storage devices,
printers and an alarming device for the watch officer.
The LES installation consists of a 19" rack with fully redundant
antennas, redundant GPS receivers for world-wide time synchronisation,
redundant modulators/transmitters, upconversion, ocean region (OR)
multiplex, storage devices, and documentation printers.