基于星敏感器的星光折射卫星自主导航方法研究

研究了基于星光折射量测进行自主确定卫星姿态及轨道的方法。这种导航方案利用高精度的CCD星敏感器,结合星光穿越大气的较精确的数学模型,来间接敏感地平,从而实现对卫星的精确定位和定姿。为了说明所提导航方案的有效性,采用推广卡尔曼滤波算法,结合模拟的测量数据对自主定轨进行了仿真。仿真结果表明,定轨精度优于100m。还分析比较了采样周期、星敏感器精度、恒星数目等因素对定轨精度的影响。总结了其变化规律,可用于提高卫星自主定轨精度。

Satellite autonomous navigation by stellar refraction based on a star sensor

An autonomous satellite attitude and orbit determination system based on the stellar refraction measurement is described. CCD star sensor with a high accurary and precise mathematical model of starlight passing through the upper atmosphere is used to indirectly sense ths earth horizon, such that the attitude and orbit of the satellite can be accurately determine. Simulation is done based on simulative measured data using the extended Kalman filtering method. Simulation result shows that the precision of orbit determination is better than 100?m. Moreover, the effects of sampling period, star sensor precision, and number of sighting stars on determining orbit precision are analyzed and compared. The changing law is presented, which can improve satellite autonomous orbit determination precision.