Error analysis of line-of-sight measurement for video satellite

Compared to ground-based observation, using video satellite to track space objects and determine the orbit has a unique advantage, which can provide strong support for space mission guarantee, object identification, important spacecraft collision warning, and so on. The accuracy of line-of-sight measurement by video satellite directly affects the final positioning accuracy; it is very necessary to analyze and calibrate the line-of-sight measurement error. In this article, a mathematical model of line-of-sight measurement is established using the transformation from image plane to object position. The error sources and the relationship between each other are analyzed comprehensively. The error of line-of-sight measurement caused by the optical axis determination error and the object detection error are calculated, respectively, and their statistical properties are studied. Finally, a concise and practical analytic formula of the error range of line-of-sight measurement is derived. Simulation results verify the theoretical analysis, and the minimum error point of line-of-sight measurement on image plane is researched. It is indicated that the effect of the satellite attitude and the position of the object on image plane are highly coupled to the error range of line-of-sight measurement.