• Updating information
• Navigational fields condition data

Historically, auxiliary functionality systems were developed for improving precision and reliability of navigational sightings. During the decades passing since creation of first differential subsystem, scope of their goals has widened.

Users require not only updating information but also solutions for problems of navigation-time field integrity control and to perform high precision relative positioning tasks and to navigate in indoor areas.

Russian Federation, possessing own global navigation system and being a country where navigation technologies are actively developed, creates a wide range of auxiliary functionality systems, including both wide-area differential correction and monitoring system, and local and regional differential subsystems.

GLONASS and GPS navigational fields monitoring system is in operation since 2007. WDCM measurements concentration stations network includes 20 facilities. Information transmission is provided through geostationary communication satellites as well as over terrestrial communication channels. Real-time and a posterior GLONASS and GPS GNSS condition data is available at www.sdcm.ru WDCM website.