Real-time GNSS Service at GFZ: Current Status and Recent Development

Real-time Global Navigation Satellite Systems (GNSS) are critical for precise and reliable positioning, navigation, and timing (PNT) services, including both civil applications with an accuracy of meter-level and geohazard early warning systems with an accuracy of cm- or even mm-level. For high-precision real-time GNSS applications, the precise orbits, clocks, hardware delays, and atmospheric information are estimated and disseminated in real time by the service provider. In this study, we introduce the current status and recent developments of the GFZ GNSS real-time analysis center. We introduce the data processing strategy for generating satellite orbits and clocks, hardware delays, and atmospheric information, and present the accuracy of the online operational products. We focus on the recent developments in improving the accuracy and reducing the latency of real-time products, such as shortening the ultra-rapid orbit processing time and improving the predicting accuracy, estimating orbits with real-time streaming data, and adopting the un-differenced ambiguity resolution in the estimation of real-time clocks and orbits. Lastly, we evaluate the real-time positioning performance using the GFZ real-time products, and demonstrate with the atmospheric augmentation information, the cm-level accuracy can be achieved within a few minutes.
The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)