System for Differential Corrections and Monitoring
The System for Differential Corrections and Monitoring (SDCM), is the satellite-based navigation augmentation system operated by Russia's Roscosmos space agency to augment the precision of the GLONASS satellite navigation system.[1] It uses the Luch Multifunctional Space Relay System to transmit correction data.[2]
SDCM's service area covers the Russian Federation. As of 2021 it had not yet been certified for use for public aviation.[3]