If you wish to contribute or participate in the discussions about articles you are invited to contact the Editor


From Navipedia
Jump to navigation Jump to search

Other SBASOther SBAS
Title SDCM
Edited by GMV
Level Basic
Year of Publication 2011
Logo GMV.png

The System for Differential Corrections and Monitoring (SDCM) is the SBAS currently being developed in the Russian Federation[1] by JSC (Russian Space Systems) [2] as a component of GLONASS.[3]

The main differentiator of SDCM with respect to other SBAS systems is that it is conceived as an SBAS augmentation that would perform integrity monitoring of both GPS and GLONASS satellites.

SDCM Ground Segment

SDCM planned station network

The main components of the SDCM Ground Segment are a network of reference stations, central processing facilities, uplink stations and terrestrial broadcast means.

The SDCM network of reference stations is composed of 19 stations in Russia and 5 stations abroad[2]. However, there are plans to expand the network to 45 stations in Russia and 12 abroad[4]. The current status of the SDCM station network can be accessed here.

The central processing facilities are located in Moscow and it is complemented by a reserve facility[5].

In addition to the GEO broadcast, it is foreseen that SDCM provides internet and GSM broadcast from a SISNeT server and an NTRIP server.[3]

Current SDCM station network (Source https://sdcm.ru/)

SDCM Space Segment

SDCM currently uses transponders on the Luch Multifunctional Space Relay System geostationary communication satellites to transmit correction and integrity data. Data distribution is performed via L1-bandwidth according to SARPs ICAO requirements and MOPS RTCA-229. [2] The SDCM Space Segment will be composed of 4 GEO satellites:

SDCM GEO Satellites[2][4]
Satellite Location Launch Status
Luch-5A 167 deg East Dec 11, 2011 Unused
Luch-5B 16 deg West Nov 3, 2012 Active
Luch-5V 95 deg East Apr 28, 2014 Active
Luch-5M 16 deg West 2020+ Planned
95 deg East 2020+ Planned
167 deg East 2020+ Planned
160 deg West 2020+ Planned

SDCM Objectives and Performances

With this architecture the whole Russian Federation will be covered as the SDCM Service Area.[6]

The SDCM objectives are:[7]

  • SBAS L1 seamless coverage by the Russian territory
  • SBAS L1 dual coverage of the central part of Russia by 2018
  • Precise positioning services by SBAS L1/L5 and precise point positioning services by L1/L3 in the GLONASS band by 2018
  • SDCM certification for LPV-200 requirements
  • Plan to use SDCM as a basis for future precise point positioning service

The positioning performance provided by SDCM will be of 1 to 1.5 meters in the horizontal plane and of 2 to 3 meters in vertical. In addition, it is expected to offer a cm-level positioning service for users at a range of 200 kilometers of the reference stations.[1]

In 2014, the observed accuracy of the system oscillated between 0.44 m and 2.19 m in the plane and from 0.23 m to 4.77 m in the vertical along most of the Russian territory. Plans beyond 2020 consider a 0.5m accuracy[4].

SDCM Future and Evolutions

The Luch 5A was launched on December 2011 and the Luch-5B on November 2012, having reached the geostationary orbit in December 2012. Luch 5V was launched on April 2014.

All current Luch satellites were to be replaced by the Luch 5M variant starting 2021 but their launches have been delayed to 2022 in the first place and again to 2025[8]. These satellites will broadcast SBAS data in L1 and L5 signals[4]. The ground stations network is also expected to grow in the next years[4].

SDCM system tests have been completed and system certification has been planned for 2020. Initial service will be SBAS L1 over Russian territory. L1/L5 SBAS and L1/L3 GLONASS precise point positioning service are under planning[9].


This article has been updated by GMV based on public information according to the references.


  1. ^ a b Glen Gibbons, Russia Building Out GLONASS Monitoring Network, Augmentation System Inside GNSS News, September/October 2009
  2. ^ a b c d SDCM at Unoosa 2015
  3. ^ a b System for Differential Correction and Monitoring Update, Sergey KARUTIN, Deputy head of division, Russian Space Systems, presented at ION GNSS 2011
  4. ^ a b c d e SDCM at Unoosa 2019.
  5. ^ http://www.unoosa.org/
  6. ^ Sergey Revnivykh (Russian Federal Space Agency), GLONASS Updates, Munich Satellite Navigation Congress, March 2011
  7. ^ Unoosa 2013
  8. ^ Luch M information
  9. ^ Global SBAS Status (FAA)