Signal-in-Space Range Analysis for Navigation Satellite Systems

Abstract

The signal-in-space range error (SISRE) constitutes a key performance indicator for all navigation satellite systems. Within the scope of this thesis, specific aspects of SISRE monitoring are addressed. The implications of inconsistencies and errors affecting the broadcast ephemeris data of the International GNSS Service (IGS) are discussed, and solutions to identified receiver-specific problems are suggested. The impact of systematic clock biases observed between the broadcast and precise clock solutions of GLONASS is examined next and satellite-specific clock corrections are derived with the objective of improving the overall GLONASS SISRE budget. Clock offsets up to 2.8 m are demonstrated, with a 0.60 m uncertainty introduced by inconsistencies between the precise clock solutions of the IGS analysis centers. An application for the estimation of observed range deviations (ORDs) in a multi-GNSS framework is finally developed, and the derived ORDs are compared against representative SISRE values from comparisons between broadcast and precise ephemerides. Overall, the compatibility of the results provides evidence of the importance of the ORDs in SISRE monitoring.