Patent ID: 6478260
Filing Date: 2002-11-12
Classification: B64G,G01C,G01S

Abstract:
An apparatus for determining star location comprising:a star tracker for sensing a plurality of positions of a first plurality of stars relative to said star tracker, said star tracker having a field of view and generating a plurality of signals corresponding to said plurality of positions in said field of view, said field of view having a boresight; a star catalog comprising a primary array having a plurality of steps with a resolution of a declination step size, each step corresponding to a secondary array containing a plurality of declination angles and right ascension angles corresponding to a plurality of positions of a second plurality of stars; and a controller coupled to said star catalog and said star tracker, said controller having control logic operative to determine a location of said boresight, determine a limit to said field of view, check a current secondary array, determine a starting right ascension angle, check a current right ascension angle, determine a star location relative to said field of view, check if said star location is in said field of view, and store said star location in a sub-catalog.