Based On Astronomical Information Satellite Autonomous Navigation

The satellite autonmous navigation system based on celestial information possess a lot of merits: independence, high accuracy and low cost. Many countries all go on extensive research in this field at present.American and Franch have succeeded in satellite applications , but our country's technology comparing with that of overseas in this aspect has yet exited biggish difference . In this situation , this thesis , taking geosynchronous satellite as researching object, systemic studies the satellite attitude control system without gyroscope and autonomous navigation technology in aspect of satellite orbital determination.The main efforts done in this thesis are as follows:1. The research on the CCD (Charge Coupled Devices) sensor information is used to determinate the satellite attitude system without gyroscope .(1) Using quaternion and MRP (Modified Rodrigues Parameters) as attitude representation , the attitude kinematics function are established . The satellite attitude dynamics function is established,that is disturbed by the first-order Markov force moment.(2) Using the quaternion as attitude representations, the attitude determination state estimator EKF (Extented Kalman Filtering) and UKF (Unscented Kalman Filtering) are designed , numerical simulation is done . The effects of the attitude representation parameters ,the estimation algorithm of system with nonlinearity , the star sensor precision , and sample period on determining attitude precision are studied.2. The research on the stellar refraction is used to determinate the satellite orbital system.(1) For the geosynchronous satellite , the precise orbit dynamics function is established in the geocentric equatorial inertial coordination , considering the influence due to the Earth shape , the Sun's and the Moon's gravitation and the sunlight pressure .(2) Satellite autonmous navigation technology based on the stellar refraction is studied . Using the observation information measured by CCD star sensors accurate determinate the horizon . Based on the observation function , the position and velocity of the satellite are determinated by the EKF and UKF . Numerical simulation is done . The observation model , the limited condition of selecting the stars , and all kinds of factor of influencing accuracy are discussed .