Patent ID: 6791673
Filing Date: 2004-09-14
Classification: G01C,G01V

Abstract:
A method for exercising surveillance over a surface from an observation point above the surface utilizing three-dimensional map data pertaining to the surface, the method comprising the steps:(1) intercepting the light rays from a surface in a field of view; (2) separating the intercepted light rays into a plurality of light-ray clusters, a light-ray cluster comprising a plurality of light-ray bundles, a light-ray bundle being the light rays from a point on the surface in the field of view, a light-ray cluster being the light-ray bundles from a region of contiguous points on the surface; (3) determining the map coordinates of each region from which a light-ray cluster comes; (4) obtaining a measure or normalized measure of the radiant power of each light-ray cluster or part thereof, spectrally modified or not, at predetermined time intervals; (5) identifying the map coordinates of a surface activity from measures or normalized measures of the radiant power of the light-ray clusters or parts thereof, spectrally modified or not.