GLONASS

The Global Navigation Satellite System GLONASS is a Russian-operated satellite navigation system, to provide users their position and time anywhere in the world or near-Earth space. GLONASS is nearly identical to the GPS system of the United States.

The complete satellite constellation should consist of 24 satellites orbiting at an altitude of 19,100 km with an orbit period of 11 hrs and 15 minutes. They are distributed into 3 orbits of 8 satellites.

Each GLONASS satellite transmits a C/A-code for standard positioning on frequency L1, and a P-code for precise positioning on L1 and L2. The P-code is only available for military purposes. Unlike GPS and Galileo, GLONASS uses a different frequency for each satellite. Radio frequency carriers used by GLONASS are channelized within the bands 1240-1260 MHz for L2 and 1597-1617 MHz for L1. The channel spacing is 0.4375 MHz for L2 and 0.5625 MHz for L1.