A
Doppler radar is a specialized
radar that uses the
Doppler effect to produce velocity data about objects at a distance. It does this by bouncing a
microwave signal off a desired target and analyzing how the object's motion has altered the frequency of the returned signal. This variation gives direct and highly accurate measurements of the component of a target's velocity relative to the radar. Doppler radars are used in
aviation, sounding satellites,
meteorology,
radar guns,
radiology and
healthcare (fall detection and risk assessment, nursing or clinic purpose), and
bistatic radar (
surface-to-air missile).