Jotron Electronics A/S TRON40GPS User Manual
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1 . 2 S Y S T E M D E S C R I P T I O N
The COSPAS/SARSAT system was introduced in 1982 as a world wide search
and rescue system with the help of satellites covering the earth’s surface. Since
the introduction of the system more than 5500 persons have been rescued by
the COSPAS/SARSAT system (June 1995). Currently the system consists of 6
different satellites in a polar orbit constellation, these satellites cover the
entire earth’s surface and receive the emergency signal from the 406 MHz
transmitter within the Tron 40GPS, more polar orbiting satellites will be avai-
lable in the future, giving a faster location and rescue time.
and rescue system with the help of satellites covering the earth’s surface. Since
the introduction of the system more than 5500 persons have been rescued by
the COSPAS/SARSAT system (June 1995). Currently the system consists of 6
different satellites in a polar orbit constellation, these satellites cover the
entire earth’s surface and receive the emergency signal from the 406 MHz
transmitter within the Tron 40GPS, more polar orbiting satellites will be avai-
lable in the future, giving a faster location and rescue time.
In addition several geostationary satellites are equipped with a 406 MHz trans-
ponder, these satellites are not able to locate the Tron 40GPS but will give an
early warning to the rescue forces, minimising the time from an emergency
occurs till the rescue forces are at the site.
ponder, these satellites are not able to locate the Tron 40GPS but will give an
early warning to the rescue forces, minimising the time from an emergency
occurs till the rescue forces are at the site.
Each emergency EPIRB in the system is programmed with its own unique
code, therefore it is vital that the ships data that is given to the dealer you
obtained your Tron 40GPS, is correct. It is also important that your EPIRB is
registered in the database for each country.This database is normally located
in the same country that the ship is registered.
code, therefore it is vital that the ships data that is given to the dealer you
obtained your Tron 40GPS, is correct. It is also important that your EPIRB is
registered in the database for each country.This database is normally located
in the same country that the ship is registered.
1 . 3 S I G N A L D E T E C T I O N [ F I G . 1 ]
When the Tron 40GPS is activated (manually or automatically) it transmits
on the frequencies 121.5 MHz and 406.025 MHz.An analogue signal is emitted on
121.5 MHz and a digital signal is transmitted on 406.025 MHz. After the Tron
40GPS is activated, the next passing satellite will detect the transmitted signal and
relay it to an antenna at a ground station, called a LUT.
on the frequencies 121.5 MHz and 406.025 MHz.An analogue signal is emitted on
121.5 MHz and a digital signal is transmitted on 406.025 MHz. After the Tron
40GPS is activated, the next passing satellite will detect the transmitted signal and
relay it to an antenna at a ground station, called a LUT.
For the 121.5 MHz signal the satellite must be within line of sight of both the
Tron 40GPS and a ground station.The ground station or LUT has a 2500 km
satellite reception radius centred at the LUT. In areas without LUT coverage
(mostly less populated areas in the southern hemisphere), signals from the
121.5 MHz transmitter will not be detected by the satellites, only by passing
aircraft’s.This is not the case with the 406 MHz transmitter, because the satel-
lites have a memory unit which stores the signals for relay to the next available
LUT giving it a truly global coverage.
Tron 40GPS and a ground station.The ground station or LUT has a 2500 km
satellite reception radius centred at the LUT. In areas without LUT coverage
(mostly less populated areas in the southern hemisphere), signals from the
121.5 MHz transmitter will not be detected by the satellites, only by passing
aircraft’s.This is not the case with the 406 MHz transmitter, because the satel-
lites have a memory unit which stores the signals for relay to the next available
LUT giving it a truly global coverage.
Once the signal is received by the LUT, it is processed for location and sent to
a Mission Control Centre (MCC).The MCC sorts the alert data according to
geographic search and rescue regions and distributes the information to the
appropriate Rescue Co-ordination Centre (RCC), or if outside the national
search and rescue area, to the appropriate MCC that covers the area where
the distress signal was detected.The RCC in turn takes the necessary action
to initiate search and rescue activities.
a Mission Control Centre (MCC).The MCC sorts the alert data according to
geographic search and rescue regions and distributes the information to the
appropriate Rescue Co-ordination Centre (RCC), or if outside the national
search and rescue area, to the appropriate MCC that covers the area where
the distress signal was detected.The RCC in turn takes the necessary action
to initiate search and rescue activities.