GPS Carrier Phase Analysis Noise on the USNO-PTB Baselines

Carrier phase GPS observations between a geodetic receiver at the Physikalisch-Technische Bundesanstalt (PTB) and two geodetic receivers at the USNO are processed using applications and extensions of the GIPSY and Bernese GPS software packages. Their results are compared with two way satellite time and frequency transfer (TWSTFT) data. It is found that algorithms that eliminate day-boundary effects require careful handling in the presence of receiver instrumental delays. Depending upon the approach chosen, time differences of several ns and frequency differences of up to 100 ps/day can develop between solution types