GPS orbit monitoring and data analysis in Canada

Abstract

The Geological Survey of Canada (GSC) and the Canada Centre for Surveying (CCS) are collaborating in a pilot project to operationally test a prototype Active Control System (ACS). Computer controlled TI4100 GPS receivers have been set up at the Algonquin Radio Observatory (ARO), Ont., the Pacific Geoscience Centre (PGC), B.C. and the Yellowknife Seismological Station (YSS), NWT to collect GPS pseudorange and phase observations for satellites in common view and ground meteorological data. The operations are fully automated including regular daily data communications to processing facilities in Ottawa. The daily ARO-PGC baseline solutions based on broadcast orbits from December 1989 to June 1990 show an RMS repeatability of 0.7 – 1.1-m corresponding to 0.3 ppm of the baseline length whereas RMS corrections to short arc orbits (positioned and oriented according to broadcast orbits) range from 5 to 51 m. The Selective Availability (SA) errors observed had the character of a second order Gauss-Markov process with σ corresponding to about 0.1 m/s in range rate and correlation time of only 4.3 minutes. ∗ ∗ Geological Survey of Canada Contribution Number GSC27190