星光折射航天器自主定轨方案比较

当星光透射大气发生折射时 ,用星光折射角精确地反映星光在大气中离地球表面的高度 ,并建立高度、航天器与地球的几何关系。通过对折射角进行观测 ,间接测得地平 ,从而改善了用地平仪直接测地平所造成的航天器自主导航精度低的不足。本文提出了几种利用星光折射的航天器自主定轨方案 ,并作了细致的仿真实验 ,对直接和间接两种测量地平方法以及几种星光折射自主定轨方案进行了分析比较。

Comparisons of Autonomous Orbit Determination Methods for Spacecraft Using Starlight Refraction

The refraction happens when starlight permeates atmosphere. The height of starlight in atmosphere is reflected accurately using refraction angle, and the geometry connection of height,spacecraft position and the earth can be set up. The geocentric direction is measured indirectly by observing refraction angle, so the low precision of position determination due to directly measurement of geocentric direction by horizontal instrument can be improved. In this paper a few schemes of autonomous real-time determination of position for spacecraft by using starlight refraction are put forward and some careful numerical experiment have been done. The two measure methods of directly and indirectly measuring geocentric direction and other methods of autonomous orbit determination are analyzed and compared.