Determination of the outline of an elevated object
AssigneeLockheed Martin Corporation
InventorsPeter W. Knibbe, John B. Stetson
Life of this patent
Estimating the term…
Abstract
A method and apparatus determines the shape of an orbiting or airborne object. A radar determines the general location and a telescope is directed toward the object to form an image of background stars, which will be occluded by the object. The image is compared with a memorized star map, to identify the region of the image in the map. Stars visible in the map which are not visible in the image are listed. The invisible stars are paired with next adjacent visible stars to form star pairs. The midpoints are identified of lines extending between star pairs. Segment lines are drawn between a midpoint and the next closest midpoint. The segment lines define an outline of the object.
Claims10
A method for determining the shape of an object in an Earth orbit, said method comprising the steps of:
- operating a radar system to determine the range, azimuth and elevation of the object relative to the radar;
- deploying an optical telescope at a location at which it is capable of viewing the region in which said object is located and which has a known relationship to the location of the radar;
- pointing said optical telescope toward said object, thereby producing an image of background stellar objects in an angular field of view encompassing said object;
- providing a memorized representation of at least some of the stellar objects in said angular field of view;
- comparing said image of background stellar objects with said memorized representation of the stellar objects as they would be expected in an unocculted field of view, to thereby identify some of those stellar objects which are occulted by said object;
- and
- using a computer processor, determining an outline of the object from said occulted and unocculted stellar objects.
An apparatus for determining the shape of an elevated object, said apparatus comprising:
- a radar system at a known location, for using electromagnetic radiation to determine the pointing azimuth and elevation of said elevated object;
- a telescope at a known location relative to the location of said radar system, said telescope being directed toward said elevated object for generating an image of said object occulting a field of background stellar objects;
- a memorized map of the locations and brightness of at least some stellar objects in a region including at least part of said image;
- a display for displaying an outline of said elevated object;
- and
- a processor for comparing said map with said image, for correlating said map with said image, and for identifying relevant stellar objects which are found in said map but missing from said image, and for generating from said missing and present stellar objects said outline of said object.
A method for determining the shape of an object in an Earth orbit which includes periods of time in which the object is in Earth's umbra, said method comprising the steps of:
- radar tracking of said object in order to determine its approximate ephemera including range, altitude, apogee, axis of orbit and phase of the orbit and location;
- deploying a radar system in a location capable of viewing the object, and operating the radar to determine the range, azimuth and elevation of the object relative to the radar;
- deploying an optical telescope at a location at which it is capable of viewing the region in which said object is located and which has a known relationship to the location of the radar;
- pointing said optical telescope toward said object, thereby producing an image of background stellar objects in an angular field of view encompassing said object;
- comparing said image of background stellar objects with a memorized representation of the stellar objects as they would be expected in an unocculted field of view, to thereby identify those stellar objects which are occulted by said object;
- and
- using a computer processor, determining an outline of the object from said occulted and unocculted stellar objects.
Dependencies are inferred from the claim text.