Error analysis of a satellite interferometer navigation system

An orthogonal system of interferometry baselines aboard a geostationary satellite is considered primarily as a global positioning and navigation system. The mathematical model based on the relationship between the measured phase differences, the known transmitter positions, and other systematic error model parameters is derived. A generalized Least‐Squares estimation procedure is used for the solution of the unknown transmitter positions. Study of the effects of the various system and error model parameters on the position accuracy reveals that this accuracy is critically dependent on the baseline length and the magnitude of the random component of the measuring errors. With a 50‐m baseline, the obtainable accuracy at a frequency of 1.5 GHz is comparable to that of the NAVSTAR/ GPS system. Considering the interest and needs of the potential users for a multicapability system, this interferometry system is considered a major improvement over existing and planned navigation systems.