Doppler error

Doppler error

In using Doppler radar, the error in the measurement of target radial velocities as a result of atmospheric refraction. These errors result, first, from the assumption of a constant wave velocity for a nonhomogeneous atmosphere and, second, the refraction or bending of the rays such that the ray path does not coincide with the geometrical straight line between the target and the radar. Errors from the former are of no practical importance, and, as in the case of elevation-angle error, the effects from the latter are negligible except for elevation angles near the horizontal.
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