Analysis of the factors that affect the ambiguities resolution process in GNSS positioning

Abstract

Integer ambiguity resolution is the process of determining the unknown number of double differences (DDs) integer cycles of the carrier phase and is essential for obtaining high accuracy in GNSS applications. As the process of ambiguity resolution is not trivial, it is necessary to use success indicators. For this purpose the Ambiguity Dilution Of Precision (ADOP) measurement was introduced, as a scalar, as a simple computation that captures the intrinsic characteristics of the ambiguities. Thus, in this project the objective is to analyze the factors that affect the process of ambiguity resolution, using the expressions in ADOP closed form. ADOP expressions for geometry-free, geometry-based and geometry fixed will be used to evaluate the impact of the modernization of GNSS (Global Navigation Satellite System) from factors such as the number of frequencies, epochs and tracked satellites, the standard deviations of carrier phase, code and ionospheric observables, in short and long baselines. (AU)