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Is NavIC available for public use?
The Indian Regional Navigation Satellite System (IRNSS), commonly known as NavIC (which stands for Navigation with Indian Constellation), is an independent regional satellite navigation system designed to provide precise real-time positioning and timing services. This system covers not only India but also an area extending approximately 1,500 kilometers (930 miles) around India’s borders, with future plans to expand its reach even further. An extended service area exists between the primary service area and a rectangular region enclosed by the 30th parallel south to the 50th parallel north and the 30th meridian east to the 130th meridian east. Within this extended area, some of the NavIC satellites are visible, although their positions may not always be accurately computable.
As of 2018, the NavIC constellation consists of eight operational satellites, with an additional two satellites on the ground, held in standby mode. This satellite constellation is responsible for enabling NavIC’s navigation and positioning capabilities.
NavIC offers two levels of services:
- Standard Positioning Service: This service is accessible for civilian use and provides open access to positioning and timing information.
- Restricted Service: This service is encrypted and reserved for authorized users, including the military.
Background:
- NavIC (Navigation with Indian Constellation) was developed due to the need for reliable navigation independent of foreign-controlled global navigation satellite systems, particularly in hostile situations.
- In 1999, the Indian military faced a critical situation when the United States denied India’s request for GPS data for the Kargil region.
Development:
- The project was approved by the Indian government in May 2006.
- ISRO (Indian Space Research Organisation) established a satellite navigation center at the ISRO Deep Space Network (DSN) campus in Byalalu, Karnataka, on May 28, 2013.
- A network of 21 ranging stations across India was set up to support the orbital determination of NavIC satellites and monitor navigation signals.
- The project aimed for complete Indian control over all aspects, including space, ground, and user segments.
- NavIC’s location in low latitudes allowed for efficient coverage with low-inclination satellites.
- Apart from civilian applications, the system had military applications, particularly in missile targeting.
Costs:
- The total project cost was initially estimated at ₹14.2 billion (approximately US$178 million).
- This included ₹3 billion for the ground segment, ₹1.5 billion per satellite (with seven planned satellites), and around ₹1.3 billion per PSLV-XL rocket for satellite launches.
- The need for two replacement satellites and additional rocket launches increased the project’s cost.
- As of March 2017, the reported costs had risen to ₹22.46 billion (approximately US$281 million).
Mandatory Usage:
- Starting from April 1, 2019, AIS 140 compliant NavIC-based vehicle tracking systems became mandatory for all commercial vehicles in India, enhancing safety and tracking capabilities.
Qualcomm Support:
- In 2020, Qualcomm introduced Snapdragon chipsets (both 4G and 5G) with support for NavIC.
- Qualcomm and ISRO signed an agreement to make NavIC available for civilian use on mobile devices.
- ISRO planned to add L1 band support to increase compatibility with existing hardware.
- Long Code support was also planned for strategic applications.
International Recognition:
- The United States recognized NavIC, along with Galileo and QZSS, as allied navigational satellite systems in accordance with the National Defense Authorization Act 2020, highlighting its global importance in navigation.
Time-frame:
- In April 2010, India announced plans to start launching NavIC satellites by the end of 2011, with a goal of launching one satellite every six months. This schedule aimed to make NavIC fully operational by 2015.
- However, the program experienced delays, and additional satellites were launched to supplement the constellation.
Satellite Launches:
- The NavIC space segment comprises seven satellites with the prefix “IRNSS-1.”
- The launch sequence started with IRNSS-1A on July 1, 2013.
- Subsequent satellite launches included IRNSS-1B on April 4, 2014, in geosynchronous orbit.
- IRNSS-1C followed on October 16, 2014, and IRNSS-1D on March 28, 2015.
- IRNSS-1E was launched on January 20, 2016, and IRNSS-1F on March 10, 2016.
- The final satellite in the initial constellation, IRNSS-1G, was launched on April 28, 2016.
- An attempt to replace IRNSS-1A with IRNSS-1H failed on August 31, 2017.
- IRNSS-1I was successfully launched on April 12, 2018, to replace IRNSS-1A.
System Description:
Space Segment:
- The NavIC constellation consists of seven satellites, with three in geostationary orbit (GEO) at longitudes 32.5° E, 83° E, and 131.5° E, approximately 36,000 km above Earth’s surface.
- The remaining four satellites are in inclined geosynchronous orbit (GSO), with two crossing the equator at 55° E and two at 111.75° E.
Ground Segment:
- The ground segment is responsible for maintaining and operating the NavIC constellation and includes several components:
- IRNSS Spacecraft Control Facility (IRSCF) at Master Control Facility (MCF) in Hassan and Bhopal.
- ISRO Navigation Centre (INC) at Byalalu, Bengaluru, and Lucknow.
- IRNSS Range and Integrity Monitoring Stations (IRIMS).
- IRNSS Network Timing Centre (IRNWT).
- IRNSS CDMA Ranging Stations (IRCDR).
- Laser Ranging Stations.
- IRNSS Data Communication Network (IRDCN).
- These components play critical roles in tracking, telemetry, remote operations, data collection, and timing accuracy for the NavIC system.
Signal:
- NavIC signals include two services: Standard Positioning Service (SPS) and Restricted Service, transmitted on L5 (1176.45 MHz) and S band (2492.028 MHz).
- The SPS signal is modulated by a 1 MHz BPSK signal, while the Restricted Service uses BOC(5,2).
- Phased array antennas broadcast navigation signals in L5 and S band frequencies to maintain coverage and signal strength.
- The satellites weigh approximately 1,330 kg, and their solar panels generate 1,400 W.
- A messaging interface within NavIC allows the command center to send warnings to specific geographic areas, enabling functions like cyclone warnings for fishermen.
Accuracy:
- The Standard Positioning Service system aims to provide an absolute position accuracy of about 5 to 10 meters across the Indian landmass.
- In the Indian Ocean and a region extending approximately 1,500 km around India, the accuracy is about 20 meters.
- This accuracy compares favorably with GPS, which achieves 5 meters under ideal conditions.
- NavIC’s advantage lies in its dual frequencies (S and L bands), which enable it to measure the difference in delay between the two frequencies, making it less dependent on atmospheric models for accurate positioning.
list of the NavIC (IRNSS) satellites, including their launch details and current status:
IRNSS Series Satellites:
- IRNSS-1A
- SVN: I001
- PRN: I01
- International Satellite ID: 2013-034A
- NORAD ID: 39199
- Launch Date: July 1, 2013
- Launch Vehicle: PSLV-XL-C22
- Orbit: Geosynchronous (IGSO) at 55°E, 29° inclined orbit
- Status: Partial Failure
- Remarks: Atomic clocks failed. The satellite is being used for NavIC’s short message broadcast service.
- IRNSS-1B
- SVN: I002
- PRN: I02
- International Satellite ID: 2014-017A
- NORAD ID: 39635
- Launch Date: April 4, 2014
- Launch Vehicle: PSLV-XL-C24
- Orbit: Geosynchronous (IGSO) at 55°E, 29° inclined orbit
- Status: Operational
- IRNSS-1C
- SVN: I003
- PRN: I03
- International Satellite ID: 2014-061A
- NORAD ID: 40269
- Launch Date: October 16, 2014
- Launch Vehicle: PSLV-XL-C26
- Orbit: Geostationary (GEO) at 83°E, 5° inclined orbit
- Status: Operational
- IRNSS-1D
- SVN: I004
- PRN: I04
- International Satellite ID: 2015-018A
- NORAD ID: 40547
- Launch Date: March 28, 2015
- Launch Vehicle: PSLV-XL-C27
- Orbit: Geosynchronous (IGSO) at 111.75°E, 31° inclined orbit
- Status: Operational
- IRNSS-1E
- SVN: I005
- PRN: I05
- International Satellite ID: 2016-003A
- NORAD ID: 41241
- Launch Date: January 20, 2016
- Launch Vehicle: PSLV-XL-C31
- Orbit: Geosynchronous (IGSO) at 111.75°E, 29° inclined orbit
- Status: Partial Failure
- Remarks: The satellite is being used for NavIC’s short message broadcast service.
- IRNSS-1F
- SVN: I006
- PRN: I06
- International Satellite ID: 2016-015A
- NORAD ID: 41384
- Launch Date: March 10, 2016
- Launch Vehicle: PSLV-XL-C32
- Orbit: Geostationary (GEO) at 32.5°E, 5° inclined orbit
- Status: Operational
- IRNSS-1G
- SVN: I007
- PRN: I07
- International Satellite ID: 2016-027A
- NORAD ID: 41469
- Launch Date: April 28, 2016
- Launch Vehicle: PSLV-XL-C33
- Orbit: Geostationary (GEO) at 129.5°E, 5.1° inclined orbit
- Status: Partial Failure
- Remarks: The satellite is being used for NavIC’s short message broadcast service.
- IRNSS-1H
- Launch Date: August 31, 2017
- Launch Vehicle: PSLV-XL-C39
- Status: Launch Failed
- Remarks: The payload fairing failed to separate, and the satellite could not reach the desired orbit. It was meant to replace defunct IRNSS-1A.
- IRNSS-1I
- SVN: I009
- PRN: I09
- International Satellite ID: 2018-035A
- NORAD ID: 43286
- Launch Date: April 12, 2018
- Launch Vehicle: PSLV-XL-C41
- Orbit: Geosynchronous (IGSO) at 55°E, 29° inclined orbit
- Status: Operational
