PL’s Proposed High Accuracy Service and Comparison to Galileo HAS and IGS Products

The Global Differential GPS (GDGPS) is a complete real-time GNSS monitoring and augmentation system with decades of experience in precise orbit determination. As part of JPL’s GDGPS group’s transition to public funding, it is intended to publicly provide access to high-quality satellite corrections in a High Accuracy System (HAS) to users over the Internet, with potential to support GPS. In its current initial offering, GDGPS HAS mainly consists of high-quality satellite orbit and clock corrections, with additional limited support for satellite code biases. In later versions, corrections will also include more comprehensive support for satellite code biases, together with support for satellite phase biases to allow for user PPP with ambiguity resolution (AR). The corrections are provided in two redundant streams, with one stream supporting GPS and Galileo, and the other supporting GPS and GLONASS. Analysis of the quality of the corrections and of PPP solutions based on these products attests to the quality of the corrections. Rms of the User Range Errors (URE) relative to post-processed products are found to be approximately 6 cm for GPS and 7 cm for Galileo. For GLONASS, the standard deviation is approximately 4 cm. PPP results show good performance as well, with PPP solutions equivalent to solutions generated based on real-time Centre National d’Etudes Spatiales (CNES) products, and better than solutions generated based on Galileo HAS Internet-based products. The results attest to the adequacy of GDGPS HAS as augmentation to GPS, Galileo, and GLONASS.