GLONASS for Precise Navigation in Space
The current stage of GLONASS evolution is aimed at meeting future user requirements of which the most important is the improved accuracy of positioning.
During the implementation of the GLONASS Space Segment Modernization Program (2012–2015), the GLONASS team is facing the situation in which it is not feasible to launch new navigation satellites because the existing constellation is comprised of GLONASS-M satellites operating beyond their guaranteed design lifetime. Nine more GLONASS-M satellites are in ground storage.
By Inside GNSS