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  • NavIC (Navigation with Indian Constellation) is the name of the independent stand-alone navigation satellite system of India
  • This system was earlier known as IRNSS (Indian Regional Navigation Satellite System).
  • The name NavIC was coined by the Hon. Prime Minister of India on the occasion of completion of the constellation in April 2016.

  • Currently, there are four global systems viz., GPS from USA, GLONASS from Russia, Galileo from European Union and BeiDou from China.
  • In addition, there are two regional systems viz., NavIC from India and QZSS from Japan.

  • GPS is the name of the navigation satellite system owned by USA. On similar lines, Russia, European Union, China, India and Japan have their own navigation satellite systems namely GLONASS, Galileo, BeiDou, NavIC and QZSS respectively.
  • GPS is not a generic term for satellite navigation. The correct term is GNSS, which comprises of all the above systems.
  • Common location tracking devices are capable of receiving signals from many or all of the above systems, including NavIC.
  • Hence it is appropriate that the devices indicate that they are capable of “GNSS” instead of “GPS”.

  • GPS is the name of the navigation satellite system owned by USA. On similar lines, Russia, European Union, China, India and Japan have their own navigation satellite systems namely GLONASS, Galileo, BeiDou, NavIC and QZSS respectively.
  • Mobile phone applications use the location value computed using signalsreceived by the phone hardware. These signals could be from many or all of the above navigation systems, including NavIC.
  • Hence it is appropriate that the applicationsin the mobile phones indicate the term “location” instead of “GPS”.

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  • GPS and GLONASS are operated by defence agencies of the respective nations. It is possible that the civilian service can be degraded or denied.
  • NavIC is an independent regional system over the Indian region and does not depend on other systems for providing position service within the service region.
  • It is fully under the control of Government of India.

NavIC, like any other navigation satellite system, consists of three segments:

  • Space segment: Consists of the constellation of satellites.
  • Ground segment: Consists of a network of ground stations that generate navigation data to be uplinked to the satellites, and subsequently to be used by the user receiver for aiding in position computation.
  • User segment: Consists of the users utilizing the navigation signals for the purpose of position, navigation, and timing.

  • International Telecommunication Union (ITU)
  • United Nations Office for Outer Space Affairs (UNOOSA)
  • International Committee on GNSS (ICG)
  • Other navigation service providers (like GPS, GLONASS, Galileo, BeiDou, QZSS)

  • NavIC is conceived and built mainly with the aim of having an independent navigation satellite system for India to remove the dependence on foreign satellite systems for navigation service requirements, especially for the strategic sector.
  • It is not built for the purpose of revenue generation.
  • However, many civilian applications are possible using free-to-air navigation signals broadcast from the satellites.
  • The industry can produce receivers capable of receiving NavIC signal and use for various applications in several areas.
  • Thus, economic benefit will accrue to the Indian economy by usage of position and navigation technologies.

  • GNSS is an acronym for global navigation satellite systems.
  • GNSS allows users worldwide to pinpoint their locations or the locations of objects, other people and goods at any given moment.

Global navigation system caters to the users in the entire world, whereas regional navigation system caters to the users in the limited service area.

  • Satellite navigation is based on the use of range measurements between navigational satellite and the user.
  • Information about the satellite’s coordinates is given to the user through navigation signal.
  • Range measurements are based on the calculation of the receiving signal time delay compared with the signals generated by the user equipment.

  • For determining position and time, a minimum of four satellites are required.
  • In ideal case, when the measurements are precise and satellite time is identical with the user’s equipment time, the user position can be computed with 3 satellites.
  • In reality, satellite time differs from the time on user’s equipment.
  • So,difference between user equipment time and satellite time also needs to be determined. That is the reason four satellites are needed.

  • There is no limit on the number of users.
  • The satellite based navigation system sends signals in broadcast mode, and any number of users within the coverage area can receive the signals.

  • Atomic clocks are highly accurate and stable clocks, with errors of less than 10 nanoseconds.
  • The low errors results in providing accurate ranging for position determination.

  • GAGAN stands for GPS Aided Geo Augmented Navigation.
  • It is a satellite based augmentation system developed primarily for safety-of-life civil aviation applications catering to the Indian airspace.
  • It provides correction and integrity messages for GPS.
  • GAGAN has been established jointly by ISRO and AAI. It is being operated and maintained by AAI.

  • Following are the major differences between GAGAN and NavIC systems:
GAGAN NavIC
An augmentation to the GPS An independent stand-alone navigation system
Provides integrity information Does not provide integrity information
Provides safety-of-life operation support Does not support safety-of-life operations

More Details

Space Infrastructure
  • Communication
  • Earth Observation
  • Navigation
  • Space Science
    • Mars Orbiter Mission
    • Chandrayaan-2
    • AstroSat
Others
  • International Cooperation
  • Occupational Health and Safety
  • Systems Reliability and Quality