Ameri-King AK-451-P-ELT - Manual (Page 10)

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SECTION 6 - THE SEARCH AND RESCUE SYSTEM
6.1 General Overview
The Ameri-King AK-451-PLB provides distress alerting via radio transmission on 406 MHz to satellites of the COSPAS-SARSAT
network and to the GEOSAR network that includes GPS latitude and longitude coordinates when GPS data is present.
The message transmitted by the Ameri-King AK-451-PLB is unique for each PLB, which provides identification of the
transmitter through computer access of registration files maintained by the National Oceanic and Atmospheric Administration or
other National Authority. Remember, if your PLB is not registered, Search and Rescue (SAR) Authorities do not know who you are,
or how to contact anyone who might know anything about your situation (Refer to section1).
Once the Ameri-King AK-451-PLB signal (406 MHz) is relayed through the LEOSAR and/or GEOSAR network, SAR forces
determine who is closest, and then track the signal using the 121.5 MHz homing frequency for intermediate and short-range location.
6.2 Satellite Detection
6.2.1 The Ameri-King AK-451-PLB transmits an encoded phase modulated radio signal to the 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).
6.2.2 COSPAS-SARSAT is an international system that uses Russian Federation and United States low altitude, near-polar
orbiting satellites (LEOSAR) that assist in detecting and locating activated 121.5/243 MHz PLBs and 406 MHz Satellite PLBs.
6.2.3 COSPAS and SARSAT satellites receive distress signals from satellite PLBs transmitting on the frequency of 406 MHz.
The COSPAS-SARSAT 406 MHz signal consists of a transmission of non-modulated carriers followed by a digital message
format that provides identification data. The 406 MHz system uses Satellite-borne equipment to measure and store the Doppler-
shifted frequency along with the digital data message and time of measurement. 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.
6.2.4 The LUT processes the Doppler-shifted signal from the LEOSAR and determines the location of the PLB; then the LUT
relays the position of the distress to a Mission Control Center (MCC) where the distress alert and location information is
immediately forwarded to an appropriate Rescue Coordination Center (RCC). The RCC dispatches Search and Rescue (SAR)
forces.
6.2.5 The COSPAS-SARSAT System includes 39 LEOSAR LUT stations, 9 GEOSAR LUT stations and over 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 MHz, but will relay the distress alert to any of the LUT stations.
6.2.6 Because most of the search and rescue forces presently are not equipped to home in on the 406 MHz Satellite signal, homing
must be accomplished at 121.5 MHz and 243.0 MHz