YANG Ting-gao, CHEN Ding

(National Time Service Center, Chinese Academy of Sciences, Xian 710600, China)

Abstract: Following a brief introduction of X-ray sources and X-ray source observational instrument system with detector and collimator, the fundamentals of spacecraft attitude determination using X-ray sources are described in some details. The configuration of X-ray star scanner, the observation of scanning over suitable X-ray source and the response function of rectangular collimator are introduced. A detailed description is given on modeling the signals from scanning observation of X-ray star scanner, and the models for single collimator X-ray star scanner and for differential collimator X-ray star scanner are compared and analyzed. The algorithm is briefly discussed on fitting model parameters of spacecraft attitude with signal curve obtained by scanning over an X-ray source using deferential collimator X-ray star scanner. Finally, the spacecraft attitude determination using coded aperture system is reviewed.

Key words: X-ray sources; X-ray star scanner; spacecraft attitude determination