PRN Codes Assigned to Russian SBAS Satellites

According to a spokesperson from the Space and Missile Systems Center, GPS Directorate, the Russian Space Agency (RSA) has been assigned L1 pseudorandom noise (PRN) C/A codes for its System of Differential Correction and Monitoring (SDCM) transponders on the Luch series of geostationary relay satellites.

SDCM is a satellite-based augmentation system that will be compatible with the U.S. Federal Aviation Administration’s Wide Area Augmentation System, the European Geostationary Navigation Overlay Service, and Japan’s MTSAT Satellite-based Augmentation System.

The SDCM transponders will be hosted on the satellites of the Luch Multifunctional Space Relay System (Mnogofunktsional’noi Kosmicheskoi Sistemy Retranslyatsii). In addition to seven transponders in the Ku-and S-bands to be used to relay communications and telemetry between low-Earth-orbiting spacecraft (such as the Russian segment of the International Space Station) and Russian ground facilities, the satellites will host COSPAS/SARSAT search and rescue transponders, as well as the SDCM transponders.

The first of the new Luch satellites, Luch-5A, was launched on December 11, 2011. The satellite has passed the initial inspection carried out at its temporary location at about 58.5 degrees east longitude. According to published documents, Luch-5A will eventually be relocated to its designated operational location at 16 degrees west longitude.

Two more Luch satellites are to be launched: Luch-5B, scheduled for launch around the end of August 2012 into an orbit at 95 degrees east longitude and Luch-5V (“V” is the transliteration of the third letter in the Russian alphabet) in 2014 into an orbit at 167 degrees east longitude (Luch-5V replaces the previously designed Luch-4 satellite).

The C/A codes assigned to the Luch SDCM transponders are as follows: Luch-5A, PRN 125; Luch-5B, PRN 140; and Luch-5V (Luch-4), PRN 141. Notification of the assignments was sent to the RSA on December 20, 2011.

No signals from the Luch-5A SDCM transponder have yet been detected by the monitoring stations of the International GNSS Service.