Abstract:

The rigid body's attitude determination is discussed using two baselines based on GPS; baseline vector coordinates are calculated with GPS double difference phases, and phase integer ambiguities are calculated with the aid of double difference pseudorange observables. By space transformation, the searching time of the integer ambiguity candidates in the confidence ellipsoid space can be reduced when dual frequency observables are available. Correctly resolving the integer ambiguities depends on the observed time and the observed pseudorange accuracy. Attitude precision is analyzed based on error propagation laws. Calculations with one periodic ephemerides data show that head or pitch precision level can reach about 2 mrads under certain conditions.

Key words: GPS, attit ude det erminat ion, phase integer ambiguit y, space tr ansformat ion