| 摘要 |
A method for geoposition determination from a platform involves using star observations to determine the orientation of the platform relative to an Earth-Centered Earth-Fixed (ECEF) frame. Observations are also made from the platform of azimuth, elevation, and possibly range of an orbiting Earth satellite. Platform orientation in an inertial frame fixed in time (IFFIT) is determined, and the satellite azimuth and elevation are transformed to the IFFIT. The satellite orbital ellipse is determined. Vectors extending from the platform frame to the foci of the ellipse are defined and converted into ECEF. The vector extending to the gravitational center of the Earth is identified and defines the location of the platform. |
