Currently, the International GNSS Service (IGS) has a well-developed global station network that includes over 500 stations in total, from which more than 360 allow tracking multi-GNSS signals. There is also a large number of permanent GNSS stations around the world operating within regional and national networks. The largest number of stations of global networks, e.g., those operated by the IGS, are located in Europe and America, as opposed to the Africa, Asia, or Oceania regions. The determination of global geodetic parameters, such as Earth rotation parameters, coordinates of the Earth’s center of mass, orbit determination, and realization of a terrestrial reference frame using GNSS observations require the use of a global, evenly distributed network of permanent GNSS stations. The selection of a proper network is a prerequisite for the representation of the Earth in the form of a discrete global grid and has a profound impact on the geophysical interpretation of information behind the temporal changes of the estimated parameters. New open-source software solving problems related to the proper selection of the GNSS station network has been developed at IGiG UPWr and made available to users.
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