Fourier Ambiguity Validation for Carrier-Phase GNSS

Journal Article (2026)
Author(s)

Peter J.G. Teunissen (TU Delft - Civil Engineering & Geosciences, The Hong Kong Polytechnic University, University of Melbourne, Curtin University)

Research Group
Mathematical Geodesy and Positioning
DOI related publication
https://doi.org/10.3390/s26072201 Final published version
More Info
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Publication Year
2026
Language
English
Research Group
Mathematical Geodesy and Positioning
Journal title
Sensors
Issue number
7
Volume number
26
Article number
2201
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6
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Abstract

Carrier-phase ambiguity validation is essential to ensure the reliability of integer ambiguity resolution in high-precision GNSS positioning. Although integer equivariant (IE) estimators provide optimal integer candidates within their class, noise and model limitations may lead to incorrect fixing. Validation procedures are therefore crucial for safeguarding the transition from float to fixed solutions, particularly in high-precision and safety-critical applications. In this contribution we introduce the concept of Fourier ambiguity validation and show how it is rooted in the principles of integer aperture (IA) estimation and its periodic representation. Unlike classical integer estimators that always return an integer solution, IA estimators introduce adjustable acceptance regions in the float ambiguity domain and fix ambiguities only when sufficient statistical evidence is present. As a result we present a general Fourier representation of IA estimators and provide an analytical description of the probabilistic properties of integer-aperture bootstrapping. We also present a hybrid description and show how the spatial and frequency representations can be mixed so as to do justice to the practical situation when carrier-phase ambiguities have a wide range of varying precision.