Ephemeris/attitude reference determination using communications links

摘要

A system (300) for determining the ephemeris and attitude for a spacecraft includes ephemeris and attitude determining subsystems (700, 800) that obtain ephemeris data (708, 806) for one or more reference spacecraft crosslinked to the spacecraft. Crosslink sensor pointing information (706, 802) is obtained for the crosslink sensors. The satellite ephemeris and attitude (712, 810) are then calculated with ephemeris and attitude determination algorithms (702, 804) based on the ephemeris data (708, 806) and crosslink sensor pointing information (706, 802). Other available information, such as stored results of previous measurements and calculations, time (710, 808), spacecraft attitude (704), information from non-crosslink sensors and ranging information may be used to enhance the accuracy or decrease the complexity of the ephemeris calculations.