The Indeterminacy of Measurements Performed by Radar Equipment

A theoretical derivation of the indeterminacies of simultaneous position and velocity measurements of a reflector when using reflected electromagnetic waves is given. It is shown that the product of the indeterminacies is given by 1/(8π)/λsc where λs is the illuminating wavelength and c the speed of light. It is shown that the necessary consequence of nonsimultaneous measurements is an uncertainty as to whether the measurements are common to the same reflector. If this uncertainty is to be overcome, the reflectors must be spaced at a distance ½cΔT where ΔT is the time separation of the position and velocity measurement.