Integrity of PPP-RTK with Regional Slant Ionospheric Grid Model and Error Bounds

This study investigates the challenges associated with ionospheric error modeling and uncertainty quantification in the integrity assessment of Precise Point Positioning with Real-Time Kinematic (PPP-RTK) systems. It introduces a novel integrity calculation framework designed specifically to address the frequent ionospheric activity encountered in low-latitude regions. By developing an error model that incorporates spatiotemporal correlations of the ionosphere and implementing a robust integrity parameter transmission mechanism, the study effectively addresses the overbounding issues that traditional methods face under active ionospheric conditions. The proposed model not only enhances the accuracy of PPP-RTK integrity calculations but also provides a more reliable framework for high-precision and high-integrity navigation applications. Experimental results demonstrate that the new model significantly improves the precision of integrity assessments across various ionospheric conditions, making it suitable for demanding navigation scenarios that require stringent accuracy and integrity standards. This advancement is particularly crucial for applications requiring high reliability and precision in environments with complex ionospheric variations, ensuring that GNSS technologies can meet the rigorous demands of modern navigation systems.