Space-borne GNSS Receiver Autonomous Integrity Monitoring by Deviations of Semi-major Axis

Some space-borne GNSS receivers, such as those used in non-geostationary satellite communication systems, require real time high integrity to ensure both real timing positioning and one pulse per second precision. Since the host satellites fly following the discipline of space dynamics, is it possible to monitor the receiver integrity by exploring orbital elements of the host satellites? In this work, the mathematical relationship between variations of orbital elements and positioning errors are derived. Accordingly, an autonomous integrity monitoring method for space-borne GNSS receivers based on deviations of semi-major axis is proposed. By monitoring the deviation of semimajor axis, which is a direct combination of the position and velocity error as indicated by our mathematical derivation, the proposed method does not rely on pseudorange and pseudorange rate residues as the existing methods. Simulations are conducted using the in-orbit GNSS data of the LingQiao satellite (NORAD ID: 40136). The results show the proposed method can effectively detect abnormal solutions.