A weak "Morse code" audio signal that gets lost in static (left side of graphic) becomes easier to identify when converted to a visual image focusing on a narrow band of signals (right side of graphic).
NIST electrical engineers Chris Holloway and Galen Koepke place transmitters in a protected air vent at the old Washington Convention Center prior to the implosion of the building.
Photo credit: Gail Porter/NIST
Experiments aimed at improving emergency radio communications will be performed by researchers from the Department of Commerce's National Institute of Standards and Technology (NIST) at the old Washington Convention Center in downtown Washington, D.C., before, during and after its demolition on Dec. 18, 2004.
The NIST work, which supports public safety programs of the U.S. departments of Homeland Security and Justice, is intended to help improve the communications capabilities of first responders. First responders who rely on radio communications often lose signals in shielded or complex environments such as the basements or elevator shafts of buildings. It also is very difficult to detect radio signals through the dense rubble of a building that has collapsed as a result of natural disasters or terrorist attacks.
To simulate disaster environments, NIST is using real-world "laboratories" - buildings that are scheduled to be imploded as part of construction and recycling projects. The old Washington Convention Center is among a series of buildings around the country that NIST is using for radio propagation experiments. Among its tasks, NIST is investigating new tools to improve communications, such as methods for detecting very weak radio signals and the use of improvised