EPIRB
An EPIRB (Emergency Position Indicating Radio Beacon), is a tracking transmitter which aid in the detection and location of boats, and people in distress. Strictly, they are radiobeacons that interface with worldwide offered service of Cospas-Sarsat, the international satellite system for search and rescue (SAR). When manually activated, or automatically activated upon immersion, such beacons send out a distress signal. The signals are monitored worldwide and the location of the distress is detected by non-geostationary satellites, and can be located by some combination of GPS trilateration and doppler triangulation. Rcom delivers manual and automatic release EPIRBS from several brands.