FEW MILLIMETER PRECISION FOR BASE-LINES IN THE CALIFORNIA PERMANENT GPS GEODETIC ARRAY

Geodetic measurements with Rogue Global Positioning System (GPS) receivers from sites in the California Permanent GPS Geodetic Array (PGGA) have been analyzed using the GIPSY orbit-determination and baseline-estimation software. Based on an unbiased selection of 23 daily measurements spanning 8 months, the low-frequency (greater-than-or-similar-to weeks) contributions to the long-term repeatabilities of baseline measurements are approximately 5, 3, and 8 mm for the east, north, and vertical components. Short-term contributions to the long-term repeatabilities were evaluated by examining data from the week of October 21, 1990, which showed the lowest short-term scatter. For this week, daily repeatabilities of 2-3 mm in the horizontal and 4 mm in the vertical have been achieved for the 172-km JPL-Pinyon baseline, consistent with carrier phase data noise of approximately 6 mm. High quality (less-than-or-similar-to 5 mm) repeatabilities have been achieved for all components of the other baselines as well.