Absolute Positioning by Collecting Global Positioning System (GPS) Data alongShort Baselines

摘要

This report addresses the problem of determining absolute positions (longitudeand latitude) from Global Positioning System (GPS) data in the presence of Selective Availability (SA). The SA-epsilon effect can be avoided if one can wait until corrected or post-fitted satellite ephemerides and clock estimates become available. However, the SA-dither effect cannot easily be eliminated from the ranging data in the field. This report considers both problems and suggests methods that have the potential to allow absolute position solutions to be obtained even with dither corrupting the satellite data. The requirements and practicality of each are reviewed. Selective availability (SA), Antispoofing (AS), Absolute positioning, Global positioning system (GPS).