Cycle Slip Detection for LEO Satellite Phase Observations in Precise Point Positioning

Teacher: Ludovico Biagi

Tutor: Nikolina Zallemi

Description: The use of LEO (Low Earth Orbit) satellite constellations for carrier phase PPP (Precise Point Positioning) has demonstrated considerable high-accuracy results in GNSS research. While a research codebase for LEO based PPP estimation already exists, cycle slip detection in phase observations is still unaddressed, naively handling  ambiguities when signal discontinuity events are detected.

The purpose of this project is to design and implement a cycle slip detection algorithm, based on: multi-frequency geometry-free linear combination of phase differentials between epochs (φ(t) − φ(t−1)); adopting a threshold-based detection criterion and validated against simulated LEO constellation data.

Upon a cycle slip occurrence, the algorithm will ensure its identification and reinitialize  carrier phase ambiguities to account for signal interruptions. The work is intended as a functional module to be integrated into an existing  research software for EKF-PPP based on GNSS and LEO integration.

Scroll to Top