PRECISE ESTIMATION PROCESS WITH FULL AVAILABILITY OF THE LINE OF SIGHT OF A TELESCOPE ON BOARD AN EARTH OBSERVATION SATELLITE

摘要

The invention relates to a method for accurately estimating the line of sight of a telescope on board and part of an Earth observation satellite comprises the following three steps. In a first step (104) the noisy attitude of the platform (4) is measured (104) regularly and absolutely by the SCAO. Then in a second step (106), carried out in parallel with the first step (104), a differential measurement with reduced noise of the line of sight of the telescope is regularly determined from a pair of images having a common area and non-uniform, acquired by at least one imaging detector. Then in a third step (108), a filter regularly estimates the angular bias existing between the real line of sight of the telescope and the real attitude of the satellite defined by the orientation of the reference trihedron SCAO by a comparison of the relative differential measurement very precise from the telescope's line of sight to the absolute measurement of the attitude of the platform which takes into account the quality of the two measurements to optimize the estimate. Figure for the abstract: Fig. 3