Session P3b: Methods and Algorithms for Timing Applications and Timescales

GPS Clock Products for NGS
Jian Yao, Saint Louis University; Rick Bennett and Andria Bilich, NOAA National Geodetic Survey
Location: Seaview A/B
Date/Time: Wednesday, Jan. 29, 4:46 p.m.

In 2021, we designed a Kalman-filter algorithm to estimate GPS satellite clocks with a high precision and accuracy based on 20 ground stations equipped with Hydrogen-maser atomic clocks [1]. From the perspective of operations, it is necessary to process all available stations to improve the robustness. As a test, we have expanded the ground network from 20 stations to 50 stations by adding 30 quartz-oscillator stations. A few days of clock products have been generated, indicating a good match with the International GNSS Service (IGS) products. We plan to process one month of data to gain more statistics. This work paves the way for the routine publication of NGS clock products.
[1] Jian Yao, Sungpil Yoon, Steve Hilla, Bryan Stressler, and Mark Schenewerk, “GPS satellite clock observation based on globally-distributed atomic clock networks,” GPS Solutions, vol. 25, pp. 1-10, 2021.