A Novel Real-time Precise Positioning Service System: Global Precise Point Positioning With Regional Augmentation

Based on precise real time orbit and clock products from a global network, the standard Precise Point Positioning (PPP) computes user states, which requires a long initialization time in order to obtain a converged solution. Conversely, the Network Real-Time Kinematic (NRTK) positioning requires additional corrections from regional or local dense network for instantaneous ambiguity resolution and state solutions. Both standard PPP and NRTK modes have their own advantages and limitations. A new approach is developed to generate undifferenced corrections in the observation domain from a regional network which can be disseminated station-by-station and applied to user observations for instantaneous ambiguity-fixing. In the proposed service, instantaneous ambiguity resolution is accessible for regions with these observation corrections as regional augmentation information, so that PPP and RTK are integrated into a unified service. The paper presented the approach for generating the undifferenced corrections and the realization of the augmented system in detail. Results from an operational service are introduced as experimental validation.