This paper discusses the impact of a new generation of mobile communication
s, Mobile Satellite Services (MSS), on the reception of GLONASS signals in
the future. The two systems are very closely located in the frequency spect
rum, and the effect of this co-location has been derived. It is shown that
the performance of GLONASS in a future GNSS-1 will be heavily affected by t
he current emissions proposed by the Globalstar consortium.