Specific Area Message Encoding

Specific Area Message Encoding (SAME) is the used to encode the Emergency Alert System (EAS) and NOAA Weather Radio (NWR) in the U.S. and Weatheradio Canada in Canada. It is also used to set off receivers in Mexico City and surrounding areas as part of Mexico's Seismic Alert System (SASMEX) and Seismic Alert Radio System (SARMEX).

From the 1960s to the 1980s, a special feature of the NOAA Weather Radio (NWR) system was the transmission of a single 1050 Hz attention tone prior to the broadcast of any message alerting the general public of significant weather events. This became known as the Warning Alarm Tone (WAT). Although it served NWR well, there were many drawbacks. Without staff at media facilities to manually evaluate the need to rebroadcast an NWR message using the Emergency Broadcast System (EBS), automatic rebroadcasting of all messages preceded by just the WAT was unacceptable and impractical. Even if stations and others with the need were willing to allow for this type of automatic capture, assuming the events for activation were critical, there was no way for automated equipment at the station to know when the message was complete and restore it back to normal operation.

SAME had its beginnings in the early 1980s when NOAA's National Weather Service (NWS) began experimenting with system using analog tones in a dual-tone multi-frequency (DTMF) format to transmit data with radio broadcasts. In 1985, the NWS forecast offices began experimenting with placing special digital codes at the beginning and end of every message concerning life- or property-threatening weather conditions targeting a specific area. The intent of what became SAME was to ultimately transmit a code with the initial broadcast of all NWR messages. The NWS started implementing SAME on the full NWR system in 1998. In 2003, NOAA established a SAME technology standard for weather radio receivers. However, the roll-out moved slowly until 1995, when the U.S. Government provided the budget needed to develop the SAME technology across the entire radio network. Nationwide implementation occurred in 1997, when the Federal Communications Commission (FCC) adopted the SAME standard as part of its new Emergency Alert System (EAS).

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