Radar speedometer

摘要

Method and apparatus for measuring the speed of a land vehicle over a surface. A narrow beam of RF energy is directed toward the surface at a substantial angle. Reflected RF energy is mixed with that transmitted to produce Doppler signals having a spectrum. The spectra of the Doppler signals are normalized by the Doppler signals being applied to an AGC circuit so that the maximum amplitudes of the spectra are substantially constant and being applied to one or more tracking band pass filters which eliminate unwanted frequency components in the spectra. From the normalized spectra, output signals are produced from which can be determined the speed of the vehicle relative to the surface.