COSPAS-SARSAT is an international satellite system designed by Canada, France, USA and Russia to assist search and rescue operations. Many other countries in the world have then joined the system.
The system is designed to quickly provide location data of vessels in danger to the teams involved in SAR (Search and Rescue) activities. A rapid intervention of the SAR teams increases the survival rate of the people involved; moreover, the location of an accident reduces both transaction costs and the risks these teams are exposed to. To achieve these goals, the system uses three components: emergency transmitters, satellites, Earth stations receivers. The transmitters, called beacons, operate with two frequencies: 406 MHz (digital) and 121.5 MHz (analog, used for radio-goniometric search). Beacons are divided into EPIRB, ELT or PLB and transmit the digital signal with the frequency of 406 MHz. The signal is received by the LEO and GEO satellites: they are satellites at low polar orbit and geostationary satellites, and their equipments are able to send back the signal to ground stations called LUT (Local Use Terminals). The LUT processes the signal obtaining location data (geographic coordinates) then transmitted to the associated MCC (Mission Control Centre). The Mission Control Centre transmits these data to other MCC or SPOC (Points of Contact for Search and Rescue) of its service area or to the RCC (Rescue Coordination Centre) for the subsequent rescue operations.
The Italian Cospas-Sarsat Satellite Station is located in Bari (Latitude 41 ° 08 '.4 North and Longitude 016 ° 50' .4 East) and is operating since 1st 1996 by Prime Minister's Decree dated 9th May 1996. It works 24 hours per day, 365 days per year, and is equipped with two dedicate antennas, one for LEOSAR system and one for GEOSAR system; this way the satellite station is able to receive and locate the danger transmitters (EPIRB-PLB-ELT) on digital frequency of 406 MHz.