GBAS performance assessment in Brazil using GNSS Multifrequency and Multi Constellation (MFMC)

Abstract

Global Navigation Satellite Systems (GNSS) have been widely used in surveying, geodesy, and navigation activities, as well as other fields. By 2021, the forecast is that the four global systems will be operational; they are the American GPS (Global Positioning System), the Russian GLONASS (GLObal NAvigation Satellite System), the European Union Galileo and the Chinese BeiDou. The use of multiple constellations can benefit global positioning, navigation, and weather users not only in terms of satellite availability, but also accuracy, integrity and reliability. Among the numerous applications of GNSS, air navigation stands out. However, due to sources of error in the signal path, such as the ionosphere and multipath, GNSS is not always suitable to meet the real-time integrity requirements for civil aviation due to the required security. When tracking signals, a GNSS receiver typically does not receive information about how contaminated its observations are by the error sources. The Ground-Based Augmentation System (GBAS) is a local GNSS differential method, which aims to provide integrity information to meet the safety requirements of air navigation, during the approaching, landing, and take-off operations. This research intends to propose a new conceptualization to enable the GBAS using multiple constellations (GLONASS, Galileo, BeiDou) to achieve corrections of greater integrity and precision in equatorial and low latitude regions. Furthermore, with the introduction of the new L5 frequency, available in modernized GPS and Galileo, further studies on GBAS can be carried out, considering the new frequency to eliminate much of the ionospheric delay, in addition to providing greater availability. (AU)