User's Manual

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7: Technical Information
7.1: System Overview
The COSPAS/SARSAT system utilises two satellite arrays to provide distress
alert and location data to search and rescue authorities.
GEOSAR – Geostationary Earth Orbit
LEOSAR – Low-altitude Earth Orbit
The GEOSAR system can provide near immediate alerting within the
coverage of the receiving satellite.
The LEOSAR system provides coverage of the polar region – beyond the
range of the GEOSAR system. It can calculate the location of distress events
using Doppler processing techniques and is less susceptible to obstructions
which could block a signal in a given direction.
The system is comprised of instruments on board the satellites which detect
the signals from the distress beacons. Ground receiving stations, referred to
as Local Users Terminals (LUTs) receive and process the satellite downlink
signal to generate the distress alerts. The distress alerts, generated by the
LUTs, are then received by Mission Control Centres (MCCs) which then
forward the alert to Rescue Co-ordination Centres (RCCs), Search and
Rescue Points of Contacts (SPOCs) and other MCCs.
7.2: GPS System
The GPS system is a satellite array that enables a GNSS receiver to
determine its position around the globe. There are a minimum of 24 satellites
orbiting the Earth providing accurate position, velocity and time information.
The SafeSea E100G has a built in 50 channel GNSS receiver and antenna
allowing reception of this positional data. The received position is then coded
into the EPIRB emergency transmission thus enabling search and rescue
teams to narrow the search area and increase the effectiveness of the rescue
operation.