Dynamic positioning at sea using the Global Positioning System.

Abstract

Dynamic positioning of a moving platform is analyzed using data from the Global Positioning System (GPS) acquired in Phase II of the Seafloor Benchmark Experiment on R/V Point Sur in August 1986. GPS position determinations are compared to simultaneous Mini-Ranger fixes. The GPS positions computed using only broadcast ephemeris data were within 20 m from the Mini-Ranger fixes when data from four satellites were used and within 30 m when data from three satellites and a geoidal height constraint were used. It was found that the position accuracy is degraded when data from a satellite reaching culmination is used.