Status of NeQuick G After the Solar Maximum of Cycle 24

The solar cycle 24 will not be registered as the most intense of the last cycles. In fact, its intensity is roughly half of the previous cycle and the ionospheric effects experienced in this cycle have been far milder than originally expected, despite having several major ionospheric storms in this period, as the so-called St. Patrick's Day's ionospheric storm. On the other hand, in this same period of time, the Galileo system has started the deployment phase and it started the In-Orbit-Validation campaign on 2013 with the first four full operational satellites, following the launch of a number of additional satellites allowing the declaration of Initial Services in December 2016 and targeting the Full Operational Capability by 2020. Thus, during this period of time, Galileo has been broadcasting the 3 Az coefficients needed to use the NeQuick G for correcting the ionospheric delay for single-frequency users. In this work, the full analysis of the performance of the NeQuick G for the last solar cycle will be presented along with the detailed analysis of some of the most relevant ionospheric storms occurred during the very same period. In general, the NeQuick G presents around 50 cm better root mean square than the Global Positioning System broadcast model for all the period of study. As an internal measure of the goodness of the NeQuick G, the percentage of slant total electron content inside of target Galileo specification will also be analyzed.

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