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Police radar guns could help identify suicide bombers

发布时间:2019-03-07 14:05:01来源:未知点击:

By Paul Marks THE radar guns police use to spot speeding motorists have inspired a version that aims to identify a would-be suicide bomber in a crowd. A radar gun fires microwave pulses at a car and measures the Doppler shift of the reflected signal to calculate its velocity. However, the strength of the reflected signal – the “radar cross section” – can provide additional information about the size and shape of the reflecting object and the material it is made from. William Fox of the Naval Postgraduate School in Monterey, California, and John Vesecky of the University of California,