Personal Locator Beacons (PLBs) transmit personalized distress signals in the 406 MHz spectrum range and aid in search and rescue missions. For example, if you are in a remote area and out of the range of cell phone service, you can use a PLB to send a personalized emergency distress signal.
BackgroundPersonal Locator Beacons (PLBs) rules were established  in 2002.
LicensingPersonal Locator Beacons (PLBs) are licensed by rule. This means an individual license is not required to operate a PLB device. You can operate a PLB device regardless of your age or citizenship.
The FCC service rules for Personal Locator Beacons (PLBs) are located in 47 C.F.R. Part 95 .
ChannelsPersonal Locator Beacons (PLBs) devices operate on frequencies between 406 MHz and 406.10 MHz.
Operating Personal Locator Beacons (PLBs)You can operate a Personal Locator Beacon (PLB) device in any place where the FCC regulates radio communications. A PLB device must be certified by the FCC. A certified PLB device has an identifying label placed on it by the manufacturer.
Each PLB device must be registered with the National Oceanic and Atmospheric Administration (NOAA). Registering your PLB device provides emergency information to search and rescue personnel. You can register your PLB device in the NOAA Beacon Registration  database.
How Personal Locator Beacons (PLBs) WorkPersonal Locator Beacons (PLBs) transmit distress signals on 406 MHz which is an internationally recognized distress frequency to the COSPAS-SARSAT satellite system. The COSPAS-SARSAT satellite system is an international program that includes 36 nations. In the United States the 406 MHz signal is monitored by the National Oceanic and Atmospheric Administration (NOAA) and the Air Force Rescue Coordination Center (AFRCC).
Each PLB is equipped with a unique identifying code which is a 15 digit alpha-numeric code. This code is transmitted in the electronic burst to the satellites and is linked to a computer database maintained by NOAA to provide your name, address, phone number and any pertinent information such as medical problems, to search and rescue personnel.
Once a PLB signal is received, the satellites can "fix" on the signal using a Doppler Shift location method, or, when a PLB is hooked up to a GPS, the GPS coordinates can be instantly transmitted without waiting for an orbiting satellite. The signal is then relayed to a Local User Terminal (LUT). These small satellite tracking stations are located all over the world and provide the link between the satellites and the Mission Control Center (MCC), which in the USA is NOAA. The signal is then passed on to the Air Force to begin the search and rescue procedures.