COSPAS-SARSAT ENHANCEMENTS
GEOSTATIONARY
SATELLITES
As you can see from the image above taken today from GOES-8,
geostationary satellites are capable of continually viewing large areas of
the Earth. These geostationary (GEO) satellites are also able to provide
immediate alerting and identification of 406 MHz beacons. The GEO
satellites are not able to use Doppler location processing since they have
no relative motion between them and the emergency beacons. Therefore, they
are not able to determine a location for a beacon. They can, however,
provide immediate alerts. This is a valuable tool for SAR personnel since
it allows them to begin their initial verification of the alert using the
NOAA beacon registration database. Often this detective work yields a
general location of the vessel or aircraft in distress and SAR assets can
be readied or dispatched to that general area. Ideally, a SARSAT or COSPAS
polar orbiting (LEO) satellite will fly over the beacon within the next
hour and calculate a Doppler location which will be forwarded to the SAR
personnel who may already be enroute.
Since every few minutes saved in reaching the scene of a distress
amounts to an increased chance of survival, the early warning capability of
GEOSAR provides a valuable tool to increase the effectiveness of the
Cospas-Sarsat system and, ultimately, save more lives. One important
warning though. It only works if the beacon is registered with NOAA. If you
have a 406 MHz beacon and have not registered it, please do so by clicking
here to get an EPIRB Form or an ELT Form.
GPS
Beacons
The next logical step in utilizing the immediate alert capabilities of
GEOSAR is to give the satellites some way of determining not just the identification,
but also the location of a distress beacon activation. This will provide
immediate alerting and locating, something Cospas-Sarsat has been striving
for since its inception.
Here's how it works: Specially made emergency beacons determine
their location using GPS that is either integrated into the beacon (called
a location protocol beacon) or fed by an external GPS receiver. This
location is then encoded into the 406 MHz signal that is transmitted by the
beacon. When this signal is received by the USMCC it is treated much the
same way as one received from the SARSAT and COSPAS satellites. The USMCC
determines which RCC should respond and immediately transmits a message to
that RCC. This means that as long as the EPIRB is within view of a satellite
(basically anywhere from 70 degrees North to 70 degrees South), a distress
message will reach rescue personnel immediately. Since they will know
exactly where you are and who you are, the response is extremely
quick!
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