Patent ID: 6741202
Filing Date: 2004-05-25
Classification: G01S

Abstract:
A method for measuring a height of a radar target located at an actual height above a horizontal plane at a location within said horizontal plane using a synthetic aperture radar, said synthetic aperture radar mounted on a moving platform, said moving platform moving along a continuous climbing path with respect to said plane, comprising the steps of:acquiring a first synthetic aperture map containing said target from a first altitude above said plane along said path; acquiring a second synthetic aperture map containing said target from a second altitude above said plane along said path; acquiring a third synthetic aperture map containing said target from a third altitude above said plane along said path; performing a monopulse measurement from information contained in said first synthetic aperture map, said second synthetic aperture map, and said third synthetic aperture map to extract a first height of said target; comparing said first synthetic aperture map and said second synthetic aperture map to extract a second height of said target using a first interferometric comparison; comparing said second synthetic aperture map and said third synthetic aperture map to extract a third height of said target using a second interferometric comparison; analyzing said first synthetic aperture map, said second synthetic aperture map and said third synthetic aperture map using shadow analysis to extract a fourth height of said target; computing a fine height from change in phase at said location by comparing said first synthetic aperture map with said second synthetic aperture map and said third synthetic aperture map; fusing said first height, said second height, said third height, said fourth height and said fine height to calculate said actual height of said target above said plane.