ACR Electronics ACR-PLB100 用户手册
Y1-03-0155 Rev. A
3
1.3
SATELLITE DETECTION
1.3.1
The beacon transmits an encoded phase modulated radio signal to the SAR satellite
portion of the COSPAS-SARSAT System. The system was developed and implemented
by the COSPAS-SARSAT Partners (Russian Federation, Canada, France and the United
States).
portion of the COSPAS-SARSAT System. The system was developed and implemented
by the COSPAS-SARSAT Partners (Russian Federation, Canada, France and the United
States).
1.3.2
COSPAS-SARSAT is an international system that uses Russian Federation and United
States low altitude, near polar orbiting satellites that assist in detecting and locating
activated 121.5/243 MHz and 406 MHz Satellite beacons. The Russian Federation
provides aboard COSMOS navigational spacecraft COSPAS payloads that are inter-
operable with the SARSAT System. In addition to weather and environmental sensors,
SARSAT payloads, provided by Canada and France, are carried aboard the United States
National Oceanic and Atmospheric Administration’s (NOAA) Advanced TIROS
environmental satellites.
States low altitude, near polar orbiting satellites that assist in detecting and locating
activated 121.5/243 MHz and 406 MHz Satellite beacons. The Russian Federation
provides aboard COSMOS navigational spacecraft COSPAS payloads that are inter-
operable with the SARSAT System. In addition to weather and environmental sensors,
SARSAT payloads, provided by Canada and France, are carried aboard the United States
National Oceanic and Atmospheric Administration’s (NOAA) Advanced TIROS
environmental satellites.
1.3.3
COSPAS and SARSAT satellites receive distress signals from the beacon transmitting on
the frequency of 406 MHz. The COSPAS-SARSAT 406 MHz satellite signal consists of
a transmission of non-modulated carrier followed by a digital message format that
provides identification data for SAR authorities. The 406 MHz system uses spacecraft-
borne equipment to measure and store the Doppler-shifted frequency data along with the
satellite digital data message including GPS data, and time of measurement to identify
your position. This information is transmitted in real time to an earth station called the
Local User Terminal (LUT), which may be within the view of the satellite, as well as
being stored for later transmission to other LUTs. In the real-time mode, the signal
detection is limited to a mutual satellite-LUT circular visibility area of about 2500 km
radius that moves with the satellite along its track. However, because of the stored-mode
capability at 406 MHz, the need for this mutual satellite-LUT visibility is not essential,
and the system is fully functional in just the global mode.
the frequency of 406 MHz. The COSPAS-SARSAT 406 MHz satellite signal consists of
a transmission of non-modulated carrier followed by a digital message format that
provides identification data for SAR authorities. The 406 MHz system uses spacecraft-
borne equipment to measure and store the Doppler-shifted frequency data along with the
satellite digital data message including GPS data, and time of measurement to identify
your position. This information is transmitted in real time to an earth station called the
Local User Terminal (LUT), which may be within the view of the satellite, as well as
being stored for later transmission to other LUTs. In the real-time mode, the signal
detection is limited to a mutual satellite-LUT circular visibility area of about 2500 km
radius that moves with the satellite along its track. However, because of the stored-mode
capability at 406 MHz, the need for this mutual satellite-LUT visibility is not essential,
and the system is fully functional in just the global mode.
1.3.4
The LUT processes the Doppler-shifted signal and determines the location of the distress
signal; then the LUT relays the position of the distress signal to a Mission Control Center
(MCC) where the distress alert and GPS location information is immediately forwarded
to an appropriate Rescue Coordination Center (RCC). The RCC dispatches Search and
Rescue (SAR) forces.
signal; then the LUT relays the position of the distress signal to a Mission Control Center
(MCC) where the distress alert and GPS location information is immediately forwarded
to an appropriate Rescue Coordination Center (RCC). The RCC dispatches Search and
Rescue (SAR) forces.
1.3.5
The COSPAS-SARSAT System includes 36 LEOSAR LUT Stations, 6 GEOSAR LUT
stations and 19 Mission Control Centers that provide real-time as well as global-mode
coverage for the Northern Hemisphere, while the Southern Hemisphere is presently
served primarily by the global-mode. Additional LUTs and MCCs are planned for
installation in the near future both in the northern and southern hemispheres.
stations and 19 Mission Control Centers that provide real-time as well as global-mode
coverage for the Northern Hemisphere, while the Southern Hemisphere is presently
served primarily by the global-mode. Additional LUTs and MCCs are planned for
installation in the near future both in the northern and southern hemispheres.
The addition of the GEOSAR Satellite system greatly improves the reaction time for a
SAR event. This satellite system has no Doppler capabilities at 406 but will relay the
distress alert to any of the LUT stations. When there is GPS data included in the distress
SAR event. This satellite system has no Doppler capabilities at 406 but will relay the
distress alert to any of the LUT stations. When there is GPS data included in the distress