The IGS MGEX Experiment as a Milestone for a Comprehensive Multi-GNSS Service

The International GNSS Service (IGS), formerly the In-ternational GPS Service, is a voluntary federation of more than 200 worldwide agencies that pool resources and permanent GPS & GLONASS station data to generate precise GPS & GLONASS products. The IGS is commit-ted to providing the highest quality data and products as the standard for Global Navigation Satellite Systems (GNSS) in support of Earth science research, multidisci-plinary applications, and education. Currently the IGS includes two GNSSs: GPS and the Russian GLONASS. In view of the ongoing GPS modernisation and the build-up of new navigation systems such as BeiDou, Galileo and QZSS, the IGS has recently established the Multi-GNSS Experiment (MGEX). MGEX serves as a platform for early experimentation and familiarisation with the emerging new signals and constellations. Aside from col-lecting multi-GNSS tracking data from a global network implemented in parallel to the core IGS network, MGEX promotes the generation of dedicated multi-GNSS orbit and clock products and the development of advanced pro-cessing algorithms. The paper describes the current status of the MGEX project, discusses early achievements and presents the long-term vision for transitioning the IGS into a fully generic multi-GNSS service