text: 16 IRIMS are currently operational and are supporting IRNSS operations few more are planned in Brunei, Indonesia, Australia, Russia, France and Japan.  CDMA ranging is being carried out by the four IRCDR stations on regular basis for all the IRNSS satellites. The IRNWT has been established and is providing IRNSS system time with an accuracy of  (2 sigma) with respect to UTC. Laser ranging is being carried out with the support of ILRS stations around the world. Navigation software is operational at INC since 1 Aug 2013. All the navigation parameters, such as satellite ephemeris, clock corrections, integrity parameters, and secondary parameters, such as iono-delay corrections, time offsets with respect to UTC and other GNSSes, almanac, text message, and earth orientation parameters, are generated and uploaded to the spacecraft automatically. The IRDCN has established terrestrial and VSAT links between the ground stations. As of March 2021, ISRO and JAXA are performing calibration and validation experiments for NavIC ground reference station in Japan. ISRO is also under discussion with CNES for a NavIC ground reference station in France. ISRO is planning a NavIC ground station at Cocos (Keeling) Islands and is in talks with the Australian Space Agency.
  Signal
  NavIC signals will consist of a Standard Positioning Service and a Restricted Service. Both will be carried on L5 (1176.45 MHz) and S band (2492.028 MHz). The SPS signal will be modulated by a 1 MHz BPSK signal. The Restricted Service will use BOC(5,2). The navigation signals themselves would be transmitted in the L5 (1176.45 MHz) & S band (2492.028 MHz) frequencies and broadcast through a phased array antenna to maintain required coverage and signal strength. The satellites would weigh approximately  and their solar panels generate 1,400 W.
  A messaging interface is embedded in the NavIC system. This feature allows the command center to send warnings to a specific geographic area. For example, fishermen using the system can be warned about a cyclone.