The deployment of the Doppler radar system in the early 1990s by the National Oceanic and Atmospheric Administration extended tornado warning lead times from five minutes to their now-annual average of 12 to 14 minutes.

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The program, known as "Biometrics-at-a-distance, " would essentially combine two pre-existing Pentagon projects: the Radar Scope, a device that can see through walls, and 2009's LifeReader, a system that uses Doppler radar to detect heartbeats.

ENGADGET: DARPA to develop biometric sensor capable of seeing through walls, pulling your heartstrings