Method of autonomous position determination using star sensor and analysis of precision for spacecraft

The best position of spacecraft is real-timely determined by using the extended Kalman filtering in order that spacecraft can run in scheduled orbit autonomously and accurately without the remote control of ground command. The elevation angular of star is observed by star sensor and horizontal instrument. During the work period of spacecraft, the system can be influenced by many factors related to hardware and software, the precision of orbit determination can be short of request. By emulating calculation, some factors that influence largely on the precision of determining position are pointed out, compared and analyzed earnestly.