Indian Regional Navigation Satellite System

The system was developed partly because access to foreign government-controlled global navigation satellite systems is not guaranteed in hostile situations, as happened to the Indian military in 1999 when the United States denied an Indian request for Global Positioning System (GPS) data for the Kargil region, which would have provided vital information.{{Cite news|url = http://timesofindia.indiatimes.com/home/science/How-Kargil-spurred-India-to-design-own-GPS/articleshow/33254691.cms|title = How Kargil spurred India to design own GPS|last = Srivastava|first = Ishan|date = 5 April 2014|access-date = 9 December 2014|work = The Times of India}} The Indian government approved the project in May 2006.{{Cite news |last=Raj |first=N. Gopal |date=2013-06-26 |title=India prepares to establish navigation satellite system |language=en-IN |work=The Hindu |url=https://www.thehindu.com/sci-tech/technology//article60043969.ece |access-date=2022-06-13 |issn=0971-751X |quote=The project to establish the IRNSS at a cost of Rs. 1,420 crores was approved by the Union Government in June 2006.}}{{Cite web |date=2024-04-01 |title=Introducing NavIC 2.0: Leveraging India’s strategic space advantage |url=https://www.orfonline.org/expert-speak/introducing-navic-2-0-leveraging-india-s-strategic-space-advantage |access-date=2024-11-10 |website=orfonline.org}}

As part of the project, the Indian Space Research Organisation (ISRO) opened a new satellite navigation centre within the campus of ISRO Deep Space Network (DSN) at Byalalu, in Karnataka on 28 May 2013.{{cite web|url=http://zeenews.india.com/news/space/isro-opens-navigation-centre-for-satellite-system_851487.html|title=ISRO opens navigation centre for satellite system|publisher=Zeenews.com|date=2013-05-28| access-date=30 June 2013}} A network of 21 ranging stations located across the country will provide data for the orbital determination of the satellites and monitoring of the navigation signal.

A goal of complete Indian control has been stated, with the space segment, ground segment and user receivers all being built in India. Its location in low latitudes facilitates coverage with low-inclination satellites. Three satellites will be in geostationary orbit over the Indian Ocean. Missile targeting could be an important military application for the constellation.{{cite news|title=India Making Strides in Satellite Technology |url=http://www.defencenews.in/defence-news-internal.asp?get=old&id=239 |access-date=26 July 2012 |newspaper=Defence News |url-status=dead |archive-url=https://web.archive.org/web/20130606194638/http://www.defencenews.in/defence-news-internal.asp?get=old&id=239 |archive-date=6 June 2013}}

The total cost of the project was expected to be {{INRConvert|14.2|b|0|lk=r}}, with the cost of the ground segment being {{INRConvert|3|b|0|nolink=yes}}, each satellite costing {{INRConvert|1.5|b|0|nolink=yes}} and the PSLV-XL version rocket costing around {{INRConvert|1.3|b|0|nolink=yes}}. The planned seven rockets would have involved an outlay of around {{INRConvert|9.1|b|0|nolink=yes}}.{{cite web|url=http://www.hindustantimes.com/india/isro-starts-countdown-to-launch-fifth-navigation-satellite-irnss-1e/story-qSv6U8T8dT4pRThRHc3VIO.html|title=Isro to launch 5th navigation satellite on Jan 20, first in 2016|website=Hindustan Times|date=18 January 2016}}{{cite news|url=http://www.dnaindia.com/scitech/1855830/report-india-s-first-ever-dedicated-navigation-satellite-launched|title=India's first ever dedicated navigation satellite launched|date=2 July 2013|access-date=24 July 2013|newspaper=DNA India}}{{cite news|url=http://www.ndtv.com/article/india/india-s-first-dedicated-navigation-satellite-placed-in-orbit-386649|title=India's first dedicated navigation satellite placed in orbit|date=2 July 2013|access-date=24 July 2013|publisher=NDTV}}

The necessity for two replacement satellites, and PSLV-XL launches, has altered the original budget, with the Comptroller and Auditor General of India reporting costs (as of March 2017) of {{INRConvert|22.46|b|0}}.{{cite web|url=https://www.geospatialworld.net/blogs/cag-pulls-up-isro-on-NavIC-delays-cost-overruns/|title=CAG pulls up ISRO on NavIC delays, cost overruns|website=Geospatial World|date=14 March 2018|last1=Datta|first1=Anusuya}}

India's Department of Space in their 12th Five Year Plan (FYP) (2012–17) stated increasing the number of satellites in the constellation from 7 to 11 to extend coverage.{{Cite journal |date=October 2011 |title=Five Year Plan |url=http://www.dst.gov.in/sites/default/files/14-wg_dos2905-report.pdf |journal=Department of Space |volume=12th FYP |pages=96}} These additional four satellites will be made during 12th FYP and will be launched in the beginning of 13th FYP (2018–23) in geosynchronous orbit of 42° inclination.{{Cite web |title=The Interoperable Global Navigation Satellite Systems Space Service Volume |url=https://www.unoosa.org/res/oosadoc/data/documents/2018/stspace/stspace75_0_html/st_space_75E.pdf |url-status=live |archive-url=https://web.archive.org/web/20181126094757/http://www.unoosa.org/res/oosadoc/data/documents/2018/stspace/stspace75_0_html/st_space_75E.pdf |archive-date=26 November 2018 |access-date=13 November 2019 |pages=62, 95}}{{Cite web |title=12th Five Year Plan report, Department of Space, DST |url=http://www.dst.gov.in/sites/default/files/14-wg_dos2905-report.pdf#page=52 |access-date=2017-06-21 |website=dst.gov.in}} Also, the development of space-qualified Indian made atomic clocks was initiated,{{Cite web |date=2018-05-16 |title=ISRO to test space robustness of indigenous atomic clocks this December |url=https://indianexpress.com/article/india/isro-to-test-space-robustness-of-indigenous-atomic-clocks-this-december/ |access-date=2019-11-13 |website=The Indian Express |language=en-IN}} along with a study and development initiative for an all optical atomic clock (ultra stable for IRNSS and deep space communication).{{Cite web |date=October 2011 |title=Report of Working Group (WG-14) |url=https://dst.gov.in/sites/default/files/14-wg_dos2905-report.pdf |access-date=4 August 2021 |website=Department of Space, Government of India}}

The NavIC Signal in Space ICD was released for evaluation in September 2014.{{cite web|url=http://gpsworld.com/irnss-signal-in-space-icd-released/|title=IRNSS Signal in Space ICD Released|date=25 September 2014|website=GPS World|access-date=7 September 2016}}

From 1 April 2019, use of AIS 140 compliant NavIC-based vehicle tracking systems were made compulsory for all commercial vehicles in India.

In December 2019, the United States Congress consented to designate NaVIC as one of their allied navigational satellite systems along with Galileo (Europe) and QZSS (Japan). The approval was as a part of National Defense Authorization Act 2020. The proposal was put forward by United States Secretary of Defense in consultation with Director of National Intelligence.{{Cite news |date=2019-12-11 |title=US Congress consents to designate India's NavIC as allied system |work=The Economic Times |url=https://economictimes.indiatimes.com/news/defence/us-congress-consents-to-designate-indias-NavIC-as-allied-system/articleshow/72468353.cms?from=mdr |access-date=2020-02-13}}{{Cite web |title=US Congress Nod To Designate India's Navigation Satellite As Allied System |url=https://www.ndtv.com/india-news/us-congress-nod-to-designate-indias-navigation-satellite-as-allied-system-2147385 |access-date=2024-11-10 |website=NDTV.com}}

In 2017, it was announced that all three SpectraTime supplied rubidium atomic clocks on board IRNSS-1A had failed, mirroring similar failures in the European Union's Galileo constellation.{{Cite web |title=SpectraTime to Supply Atomic Clocks to IRNSS {{!}} Inside GNSS |url=http://www.insidegnss.com/node/789 |url-status=dead |archive-url=https://web.archive.org/web/20170626094324/http://www.insidegnss.com/node/789 |archive-date=26 June 2017 |access-date=2017-06-21 |website=www.insidegnss.com |language=en}}{{Cite web |title=Spectratime Awarded Contract To Supply Rubidium Space Clocks To IRNSS |url=http://www.spacedaily.com/reports/Spectratime_Awarded_Contract_To_Supply_Rubidium_Space_Clocks_To_IRNSS_999.html |access-date=2017-06-21 |website=spacedaily.com}} The first failure occurred in July 2016, followed soon after by the two other clocks on IRNSS-1A. This rendered the satellite non-functional and required replacement.{{Cite news |last=D.S. |first=Madhumathi |title=Atomic clocks on indigenous navigation satellite develop snag |url=http://www.thehindu.com/news/national/Atomic-clocks-on-indigenous-navigation-satellite-develop-snag/article17114134.ece |access-date=2017-01-31 |newspaper=The Hindu |language=en}} ISRO reported it had replaced the atomic clocks in the two standby satellites, IRNSS-1H and IRNSS-1I in June 2017. The subsequent launch of IRNSS-1H, as a replacement for IRNSS-1A, was unsuccessful when PSLV-C39 mission failed on 31 August 2017.{{cite web |author1=Vasudevan Mukund |date=2 September 2017 |title=India's 'GPS' Remains Unfinished |url=https://thewire.in/173088/irnss-isro-pslv-c39-spectratime-atomic-clocks-space-debris/ |archive-url=https://web.archive.org/web/20180126214443/https://thewire.in/173088/irnss-isro-pslv-c39-spectratime-atomic-clocks-space-debris/ |archive-date=26 January 2018 |access-date=26 January 2018 |website=The Wire |location=Wayback Machine}} The second standby satellite, IRNSS-1I, was successfully placed into orbit on 12 April 2018.

In July 2017, it was reported that two more clocks in the navigational system had also started showing signs of abnormality, thereby taking the total number of failed clocks to five, in May 2018 a failure of a further 4 clocks was reported, taking the count to 9 of the 24 in orbit.{{Cite news |last=D.S. |first=Madhumathi |date=2018-05-05 |title=ISRO's clock to prop up India's own GPS |url=https://www.thehindu.com/news/national/isros-clock-to-prop-up-indias-own-gps/article23787959.ece |access-date=2019-12-21 |work=The Hindu |language=en-IN |issn=0971-751X}}

As a precaution to extend the operational life of navigation satellite, ISRO is running only one rubidium atomic clock instead of two in the remaining satellites.

{{As of|2023|May}} only four first generation satellites were capable of providing navigation services{{Cite web |date=2023-05-29 |title=New NavIC satellite launching today: why a regional navigation system matters to India |url=https://indianexpress.com/article/explained/explained-sci-tech/new-navic-satellite-launching-today-why-a-regional-navigation-system-matters-to-india-8633947/ |archive-url=https://web.archive.org/web/20230529024145/https://indianexpress.com/article/explained/explained-sci-tech/new-navic-satellite-launching-today-why-a-regional-navigation-system-matters-to-india-8633947/ |archive-date=29 May 2023 |access-date=2023-06-01 |work=The Indian Express |quote=Currently, only four IRNSS satellites are able to provide location services, according to ISRO officials. The other satellites can only be used for messaging services such as providing disaster warnings or potential fishing zone messages for fishermen.}} which is the minimum number required for service to remain operational.{{Cite web |title=FAQ Navigation |url=https://www.isro.gov.in/FAQ_Navigation.html |access-date=2023-06-01 |website=www.isro.gov.in |quote=For determining position and time, a minimum of four satellites are required.}}

{{As of|2024|September}} only four satellites IRNSS-1B, IRNSS-1F, IRNSS-1I and NVS-01 were capable of providing navigation services.{{Cite web |title=Indian Navic System |url=https://sansad.in/getFile/loksabhaquestions/annex/182/AU2548_Zpuaoq.pdf?source=pqals |page=2 |quote=Currently, there are four functional satellites providing PNT service.}}{{Cite AV media |url=https://www.youtube.com/watch?v=4Fy63bgQNGE&t=2840s |title=Sardar Patel Memorial Lecture 2024 'Indian Space Odyssey In Search of New Frontiers' by S. Somanath |date=2024-10-31 |minutes= |time=47 min 20 sec. |quote=Four satellites providing PNT service (IRNSS-1B, 1F, 1I,and NVS-01).}}

In order to reduce the dependency on imported frequency standards ISRO's Space Applications Centre (SAC), Ahmedabad had been working on domestically designed and developed Rubidium based atomic clocks. To overcome the clock failures on first generation navigation satellites and its subsequent impact on NavIC's position, navigation, and timing services, these new clocks would supplement the imported atomic clocks in next generation of navigation satellites.{{Cite book |last1=Bandi |first1=Thejesh N. |title=2019 URSI Asia-Pacific Radio Science Conference (AP-RASC) |last2=Kaintura |first2=Jaydeep |last3=Saiyed |first3=Azhar R. |last4=Ghosal |first4=Bikash |last5=Jain |first5=Pratik |last6=Sharma |first6=Richa |last7=Priya |first7=Priyanka |last8=Shukla |first8=Keya |last9=Mandal |first9=Sarathi |date=March 2019 |isbn=978-908-25987-5-9 |pages=1 |chapter=Indian Rubidium Atomic Frequency Standard (IRAFS) Development for Satellite Navigation |doi=10.23919/URSIAP-RASC.2019.8738208 |chapter-url=https://ieeexplore.ieee.org/document/8738208 |last10=Reddy |first10=Niranjan |last11=Soni |first11=Ashish |last12=Somani |first12=Sandip |last13=Patel |first13=Arvind |last14=Attri |first14=Deepak |last15=Mishra |first15=Deepak |s2cid=195225382}}{{Cite news |date=2015-05-20 |title=India developing atomic clocks for use on satellites |url=https://www.thehindu.com/news/national/tamil-nadu/india-developing-atomic-clocks-for-use-on-satellites/article7229191.ece |access-date=2022-12-30 |work=The Hindu |language=en-IN |issn=0971-751X}}{{Cite web |title=A desi atomic clock |url=https://www.indiatoday.in/magazine/up-front/story/20180521-isro-space-applications-centre-builds-atomic-clock-aerospace-technology-1231716-2018-05-10 |access-date=2022-12-30 |website=India Today |language=en}}{{Cite web |title=Five new advanced navigation satellites for strategic needs – The New Indian Express |url=https://www.newindianexpress.com/thesundaystandard/2022/Nov/27/five-new-advanced-navigation-satellitesfor-strategic-needs-2522483.html |access-date=2022-12-30 |website=www.newindianexpress.com}}

On 5 July 2017, ISRO and Israel Space Agency (ISA) signed an Memorandum of Understanding to collaborate on space qualifying a Rubidium Standard based on AccuBeat model AR133A and to test it on an ISRO satellite.

The clocks are utilised by the NVS series of satellites. As part of the Times Dissemination Project, which is overseen by the Ministry of Consumer Affairs, Food, and Public Distribution, NavIC will take the position of GPS as the reference time provider at the National Physical Laboratory of India from 2025.{{Cite news |last=Dash |first=Dipak K |date=2025-01-28 |title=Now, India will move to 'one nation, one time', thanks to desi satellites network |url=https://timesofindia.indiatimes.com/india/now-india-will-move-to-one-nation-one-time-thanks-to-desi-satellites-network/articleshow/117615893.cms |access-date=2025-01-29 |work=The Times of India |issn=0971-8257}}

In accordance with the range requirements for NavIC for both military and commercial applications, Defence Research and Development Organisation, through the Technology Development Fund scheme, has commissioned Accord Software and Systems, to build a tailored and flexible IRNSS Network Timing system domestically. Using NavIC data, the receiver chip will obtain and distribute Indian time for navigation. India currently depends on the US for this service.{{Cite web |last=Khanna |first=Bosky |date=2024-07-12 |title=DRDO partners with Bengaluru firm for Indigenous NavIC chip development |url=https://www.newindianexpress.com/states/karnataka/2024/Jul/12/drdo-partners-with-bengaluru-firm-for-indigenous-navic-chip-development |access-date=2024-07-23 |website=The New Indian Express |language=en}}

In 2020, Qualcomm launched four Snapdragon 4G chipsets and one 5G chipset with support for NavIC.{{Cite web |last1=Sarkar |first1=Debashis |date=21 January 2020 |title=Qualcomm launches three chipsets with Isro's Navic GPS for Android smartphones |url=https://timesofindia.indiatimes.com/gadgets-news/qualcomm-launches-three-chipsets-with-isros-NavIC-gps-for-android-smartphones/articleshow/73475177.cms |website=The Times of India}}{{Cite web |title=Launch of mobile chipset compatible to NavIC - ISRO |url=https://www.isro.gov.in/update/21-jan-2020/launch-of-mobile-chipset-compatible-to-NavIC |url-status=dead |archive-url=https://web.archive.org/web/20220804152245/https://www.isro.gov.in/update/21-jan-2020/launch-of-mobile-chipset-compatible-to-navic |archive-date=4 August 2022 |access-date=2020-01-22 |website=Department of Space, Indian Space Research Organisation}} NavIC is planned to be available for civilian use in mobile devices, after Qualcomm and ISRO signed an agreement.{{Cite news |date=14 October 2019 |title=NavIC support in upcoming Mobile, Automotive and IoT Platforms is poised to deliver superior Location-Based services to India's Industries and Technology Ecosystem Through Qualcomm |url=https://www.isro.gov.in/update/14-oct-2019/NavIC-support-upcoming-mobile-automotive-and-iot-platforms-poised-to-deliver |url-status=dead |archive-url=https://web.archive.org/web/20191016193800/https://www.isro.gov.in/update/14-oct-2019/navic-support-upcoming-mobile-automotive-and-iot-platforms-poised-to-deliver |archive-date=16 October 2019 |access-date=19 October 2019 |publisher=Indian Space Research Organisation}} To increase compatibility with existing hardware, ISRO will add L1 band support. For strategic application, Long Code support is also coming.{{Cite news |last=Koshy |first=Jacob |date=2022-10-26 |title=ISRO to boost NavIC, widen user base of location system |url=https://www.thehindu.com/news/national/isro-to-upgrade-indian-gps-navic-to-widen-user-base/article66056505.ece |access-date=2022-10-28 |work=The Hindu |language=en-IN |issn=0971-751X}}{{Cite web |last=Bordoloi |first=Pritam |date=2022-10-03 |title=India's Indigenous Navigation System Can Make Your Phones Expensive |url=https://analyticsindiamag.com/indias-indigenous-navigation-system-can-make-your-phones-expensive/ |access-date=2022-10-28 |website=Analytics India Magazine |language=en-US}}

On December 7, 2023, Qualcomm revealed that select chipset platforms will enable NavIC L1 signals. The Qualcomm location suite, supports up to seven satellite constellations simultaneously and allows for faster Time to First Fix (TTFF) position acquisition for enhanced location-based services. It also makes use of all of NavIC's L1 and L5 signals for precise positioning. In the second half of 2024, Qualcomm chipset platforms will add further support for the NavIC L1 signals, and in the first half of 2025, commercial products that support the NavIC L1 signals should be available for sale.{{Cite news |last= |first= |date=2023-12-07 |title=Qualcomm announces NavIC support in select chipset starting H2 2024 |url=https://www.thehindu.com/sci-tech/technology/qualcomm-announces-navic-support-in-select-chipset-starting-h2-2024/article67613660.ece |access-date=2024-09-18 |work=The Hindu |language=en-IN |issn=0971-751X}}{{Cite web |title=Qualcomm Announces Support for India’s NavIC Satellite Navigation System L1 signals in Commercial Chipset Platforms |url=https://www.qualcomm.com/news/releases/2023/12/qualcomm-announces-support-for-india-s-navic-satellite-navigatio |access-date=2024-09-18 |website=www.qualcomm.com |language=en}}

In April 2010, it was reported that India plans to start launching satellites by the end of 2011, at a rate of one satellite every six months. This would have made NavIC functional by 2015. But the program was delayed,{{cite news|author=S. Anandan |url=http://www.thehindu.com/sci-tech/article393892.ece |title=Launch of first satellite for Indian Regional Navigation Satellite system next year |newspaper=The Hindu |date=10 April 2010 |access-date=2010-12-30}} and India also launched 3 new satellites to supplement this.{{cite web |author=H. Pathak |url=http://informationmadness.com/technology/tech-tips/3684-3-satellites-to-be-launched-by-isro-on-20th-april.html |title=3 Satellites To Be Launched By ISRO |url-status=dead |archive-url=https://web.archive.org/web/20110417015013/http://informationmadness.com/technology/tech-tips/3684-3-satellites-to-be-launched-by-isro-on-20th-april.html |archive-date=17 April 2011}}

Seven satellites with the prefix "IRNSS-1" will constitute the space segment of the IRNSS. IRNSS-1A, the first of the seven satellites, was launched on 1 July 2013.{{cite web|url=http://www.isro.org/scripts/futureprogramme.aspx#Satellite|title=ISRO's Future programme|publisher=ISRO|access-date=18 May 2013}}{{cite web|url=http://www.thehindubusinessline.com/news/countdown-begins-for-pslvc22-launch/article4863108.ece|title=Countdown begins for PSLV-C22 launch|work=Business Line|date=29 June 2013 |access-date=2013-06-29}} IRNSS-1B was launched on 4 April 2014 on-board PSLV-C24 rocket. The satellite has been placed in geosynchronous orbit.{{cite news | url=http://timesofindia.indiatimes.com/india/Isro-successfully-launches-navigation-satellite-IRNSS-1B/articleshow/33240651.cms | title=Isro successfully launches navigation satellite IRNSS-1B | work=The Times of India| date=4 April 2014 | access-date=4 April 2014}} IRNSS-1C was launched on 16 October 2014,{{cite web|title=ISRO puts India's Navigation satellite IRNSS 1B into orbit|url=http://news.biharprabha.com/2014/04/isro-puts-second-irnss-navigation-satellite-into-orbit/|agency=Indo-Asian News Service|publisher=news.biharprabha.com|access-date=4 April 2014}} IRNSS-1D on 28 March 2015,{{cite news|url=http://timesofindia.indiatimes.com/india/India-successfully-launches-IRNSS-1D-fourth-of-seven-navigation-satellites/articleshow/46727095.cms|title=India successfully launches IRNSS-1D, fourth of seven navigation satellites|work=The Times of India|date=28 March 2015 |access-date=7 September 2016}} IRNSS-1E on 20 January 2016,{{Cite web|title = India launches 5th navigation satellite IRNSS-1E powered by PSLV rocket|url = http://www.hindustantimes.com/india/india-launches-5th-navigation-satellite-irnss-1e-powered-by-psl-rocket/story-iQcSrv7tV5sL3nfU49kLII.html|website = Hindustan Times|date = 20 January 2016|access-date = 2016-01-20}} IRNSS-1F on 10 March 2016 and IRNSS-1G was launched on 28 April 2016.{{cite news|url=http://www.business-standard.com/article/current-affairs/india-gets-its-own-gps-with-successful-launch-of-7th-navigation-satellite-116042800308_1.html|title=India gets its own GPS with successful launch of 7th navigation satellite|first=T. E.|last=Narasimhan|date=29 April 2016|work=Business Standard|access-date=7 September 2016}}

The eighth satellite, IRNSS-1H, which was meant to replace IRNSS-1A, failed to deploy on 31 August 2017 as the heat shields failed to separate from the 4th stage of the rocket. IRNSS-1I was launched on 12 April 2018 to replace it.{{Cite web|title = IRNSS-1I|url = https://www.isro.gov.in/Spacecraft/irnss-1i|access-date = 19 October 2019|website = isro.gov.in|publisher = Indian Space Research Organisation|archive-date = 11 April 2018|archive-url = https://web.archive.org/web/20180411050506/https://www.isro.gov.in/Spacecraft/irnss-1i|url-status = dead}}{{Cite news|title = PSLV-C41/IRNSS-1I|url = https://www.isro.gov.in/launcher/pslv-c41-irnss-1i|date = 12 April 2018|access-date = 19 October 2019|website = isro.gov.in|publisher = Indian Space Research Organisation|archive-date = 6 April 2018|archive-url = https://web.archive.org/web/20180406230840/https://www.isro.gov.in/launcher/pslv-c41-irnss-1i|url-status = dead}}

The IRNSS system comprises a space segment and a support ground segment.

The constellation consists of 7 satellites. Three of the seven satellites are located in geostationary orbit (GEO) at longitudes 32.5° E, 83° E, and 131.5° E, approximately {{convert|36000|km|abbr=on}} above Earth's surface. The remaining four satellites are in inclined geosynchronous orbit (GSO). Two of them cross the equator at 55° E and two at 111.75° E.{{Cite web|url=http://www.isac.gov.in/navigation/irnss.jsp|title=IRNSS|website=isac.gov.in|access-date=2017-06-08}}{{cite web|url=http://www.asmmag.com/news/first-irnss-satellite-by-december-|title=First IRNSS satellite by December|date=5 May 2009|work=Magazine article|publisher=Asian Surveying and Mapping

|access-date=2009-05-05}} {{dead link|date=October 2013}}{{cite web | url=http://timesofindia.indiatimes.com/home/science/How-Kargil-spurred-India-to-design-own-GPS/articleshow/33254691.cms | title=How Kargil spurred India to design own GPS | work=The Times of India | date=5 April 2014 | access-date=28 April 2016}}

The ground segment is responsible for the maintenance and operation of the IRNSS constellation. The ground segment comprises:

• IRNSS Spacecraft Control Facility (IRSCF)
• ISRO Navigation Centre (INC)
• 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)

File:IRNSS Series 1.jpg

The IRSCF is operational at Master Control Facility (MCF), Hassan and Bhopal. The MCF uplinks navigation data and is used for tracking, telemetry and command functions. Seven {{convert|7.2|m|adj=on}} FCA and two {{convert|11|m|adj=on}} FMA of IRSCF are currently operational for LEOP and on-orbit phases of IRNSS satellites.{{cite web|author=K. Radhakrishnan|date=29 December 2013|title=Mars and more, final frontier|url=https://www.deccanchronicle.com/131229/commentary-sunday-chronicle/article/mars-and-more-final-frontier|access-date=28 April 2016|work=Deccan Chronicle}}

The INC established at Byalalu performs remote operations and data collection with all the ground stations. The ISRO Navigation Centers (INC) are operational at Byalalu, Bengaluru and Lucknow. INC1 (Byalalu) and INC2 (Lucknow) together provide seamless operations with redundancy.

16 IRIMS are currently operational and are supporting IRNSS operations.{{Cite web |date=3 February 2022 |title=75 Major Activities of ISRO |url=https://www.isro.gov.in/sites/default/files/article-files/azadi-ka-amrit-mahotsav/75-major-events-of-isro-coffee-table-book/coffee_table_book_-_05-02-22_-_fv.pdf |archive-url=https://web.archive.org/web/20220218074246/https://www.isro.gov.in/sites/default/files/article-files/azadi-ka-amrit-mahotsav/75-major-events-of-isro-coffee-table-book/coffee_table_book_-_05-02-22_-_fv.pdf |archive-date=18 February 2022 |quote=ISTRAC has established a network of stations to support IRNSS satellites consisting of four IRCDR stations (Hassan, Bhopal, Jodhpur and Shillong), 16 IRIMS stations (Bengaluru, Hassan, Bhopal, Jodhpur, Shillong, Dehradun, Port Blair, Mahendragiri, Lucknow, Kolkata, Udaipur, Shadnagar, Pune and Mauritius). ISTRAC has also established ISRO Navigation Centre-1, including an IRNWT facility at Bengaluru and ISRO Navigation Centre-2, including an IRNWT facility at Lucknow.}} A few more are planned in Brunei, Indonesia, Australia, Russia, France and Japan.{{Cite web |last=Kunhikrishnan |first=P |date=20 June 2019 |title=Update on ISRO's International Cooperation |url=https://www.unoosa.org/documents/pdf/copuos/2019/copuos2019tech44E.pdf |page=5 |quote=Brunei, Indonesia, Australia, Russia, France, Japan (IRIMS)}} CDMA ranging is being carried out by the four IRCDR stations on a regular basis for all the IRNSS satellites. The IRNWT has been established and is providing IRNSS system time with an accuracy of {{convert|2|ns|s|lk=on|abbr=on}} (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.{{Cite news|date=16 March 2021|title=Quad push: ISRO taking space ties with US, Japan and Australia to a higher orbit|work=The Economic Times|url=https://economictimes.indiatimes.com/news/defence/quad-push-isro-taking-space-ties-with-us-japan-and-australia-to-a-higher-orbit/articleshow/81530295.cms|access-date=2021-03-17}} ISRO is also under discussion with CNES for a NavIC ground reference station in France.{{Cite web|date=20 March 2021|title=India, France Working On 3rd Joint Space Mission, Says ISRO Chairman|url=https://www.ndtv.com/india-news/india-france-working-on-3rd-joint-space-mission-says-isro-chairman-k-sivan-2395047|access-date=2021-03-21|website=NDTV}} ISRO is planning a NavIC ground station at Cocos (Keeling) Islands and is in talks with the Australian Space Agency.{{Cite web|date=2021-03-26|title=Gaganyaan, India's human space mission, will use 'green propulsion': ISRO|url=https://www.hindustantimes.com/india-news/gaganyaan-india-s-human-space-mission-will-use-green-propulsion-isro-101616776504769.html|access-date=2021-04-01|website=Hindustan Times|language=en}}

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).{{cite web|url=https://gssc.esa.int/navipedia/index.php/NAVIC|title=Navigation Indian Constellation (NAVIC)|access-date=December 1, 2022|publisher=ESA}} 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 {{cvt|1330|kg}} 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.{{Cite news|url=http://timesofindia.indiatimes.com/city/ahmedabad/indian-gps-for-public-use-by-year-end/articleshow/57470942.cms|title=Indian 'GPS' for public use by year-end|work=The Times of India|access-date=2017-06-08}}

The Standard Positioning Service system is intended to provide an absolute position accuracy of about 5 to 10 metres throughout the Indian landmass and an accuracy of about {{convert|20|m}} in the Indian Ocean as well as a region extending approximately {{Convert|1500|km|abbr=on}} around India.{{Cite web |date=March 5, 2017 |title=Indian 'GPS' for public use by year-end |url=https://timesofindia.indiatimes.com/city/ahmedabad/indian-gps-for-public-use-by-year-end/articleshow/57470942.cms |access-date=2022-12-09 |website=The Times of India |language=en}}A. Bhaskaranarayana Director SCP/FMO & Scientific Secretary Indian Space Research Organisation – [http://www.oosa.unvienna.org/pdf/icg/2008/expert/2-3.pdf Indian IRNSS and GAGAN] {{webarchive|url=https://web.archive.org/web/20101205044458/http://www.oosa.unvienna.org/pdf/icg/2008/expert/2-3.pdf |date=5 December 2010 }} GPS, for comparison, has a position accuracy of 5 m under ideal conditions.{{Cite web |title=GPS.gov: GPS Accuracy |url=https://www.gps.gov/systems/gps/performance/accuracy/ |access-date=2022-12-09 |website=www.gps.gov}} However, unlike GPS, which is dependent only on L-band, NavIC has dual frequencies (S and L bands). When a low-frequency signal travels through atmosphere, its velocity changes due to atmospheric disturbances. GPS depends on an atmospheric model to assess frequency error, and it has to update this model from time to time to assess the exact error. In NavIC, the actual delay is assessed by measuring the difference in delay of the two frequencies (S and L bands). Therefore, NavIC is not dependent on any model to find the frequency error and can be more accurate than GPS.{{Cite news | url=http://timesofindia.indiatimes.com/home/science/get-ready-indias-own-gps-set-to-hit-the-market-early-next-year/articleshow/58876680.cms | title=Get ready! India's own GPS set to hit the market early next year - Times of India| website=The Times of India| date=28 May 2017}}

ISRO will be launching five next generation satellite featuring new payloads and extended lifespan of 12 years. Five new satellites viz. NVS-01, NVS-02, NVS-03, NVS-04 and NVS-05 will supplement and augment the current constellation of satellites. The new satellites will feature the L5 and S band and introduces a new interoperable civil signal in the L1 band in the navigation payload and will use Indian Rubidium Atomic Frequency Standard (iRAFS.){{Cite web|date=10 December 2019|title=Indigenous Atomic Clock and Monitoring Unit for NavIC|url=https://www.unoosa.org/documents/pdf/icg/2019/icg14/WGD/icg14_wgd_09.pdf}}{{Cite book|last1=Bandi|first1=Thejesh N.|last2=Kaintura|first2=Jaydeep|last3=Saiyed|first3=Azhar R.|last4=Ghosal|first4=Bikash|last5=Jain|first5=Pratik|last6=Sharma|first6=Richa|last7=Priya|first7=Priyanka|last8=Shukla|first8=Keya|last9=Mandal|first9=Sarathi|last10=Reddy|first10=Niranjan|last11=Soni|first11=Ashish|title=2019 URSI Asia-Pacific Radio Science Conference (AP-RASC) |chapter=Indian Rubidium Atomic Frequency Standard (IRAFS) Development for Satellite Navigation |chapter-url=https://ieeexplore.ieee.org/document/8738208|year=2019 |pages=1|doi=10.23919/URSIAP-RASC.2019.8738208|isbn=978-908-25987-5-9 |s2cid=195225382 }} This introduction of the new L1 band will help facilitate NavIC proliferation in wearable smart and IoT devices featuring a low power navigation system. NVS-01 is a replacement for IRNSS-1G satellite and was launched on GSLV in 2023.{{Cite web|url=https://www.isro.gov.in/sites/default/files/annualreport2018-19.pdf|title=Annual Report of Department of Space 2018-19|date=28 May 2019|url-status=live|archive-url=https://web.archive.org/web/20190527183016/https://www.isro.gov.in/sites/default/files/annualreport2018-19.pdf|archive-date=27 May 2019|access-date=13 November 2019}}{{cite web |title=ANNUAL REPORT 2020-2021 |url=https://www.isro.gov.in/sites/default/files/anual_report_2020-2021_english.pdf |url-status=dead |archive-url=https://web.archive.org/web/20210425173704/https://www.isro.gov.in/sites/default/files/anual_report_2020-2021_english.pdf |archive-date=25 April 2021 |access-date=6 March 2021 |publisher=ISRO |page=47 |quote="IRNSS-1A and IRNSS-1G are currently being used for short messaging services."}}{{cite news |date=2023-05-29 |title=NVS-01 placed into orbit |url=https://www.tribuneindia.com/news/nation/nvs-01-placed-into-orbit-512442 |work=The Tribune}}

ISRO has plans for a total of 7 NVS series satellites (including already launched NVS-1) for civilian navigation requirements. The IRNSS network is, as of November 2024, confined to strategic use by the Indian Armed Forces. They will be equipped with L1 band along with the L5 and S band. The system will provide an accuracy of {{Convert|10|m|abbr=on}} within India, {{Convert|20|m|abbr=on}} for the area surrounding India by {{Convert|1500|km|abbr=on}}.{{Cite web |date=2024-11-09 |title=India to have its own navigation system for citizens, Isro to launch 7 NaVIC satellites |url=https://www.firstpost.com/india/india-to-have-its-own-navigation-system-for-citizens-isro-to-launch-7-navic-satellites-13833642.html#amp_tf=From%20%251$s&aoh=17311356723830&csi=0&referrer=https://www.google.com&share=https://www.firstpost.com/india/india-to-have-its-own-navigation-system-for-citizens-isro-to-launch-7-navic-satellites-13833642.html |access-date=2024-11-10 |website=Firstpost |language=en-us}}{{Cite web |date=2024-11-09 |title=How ISRO Planning To Make Regional Navigation System NaVIC Accessible To Civilians - INSPACe Chairperson Explains |url=https://www.timesnownews.com/technology-science/how-isro-planning-to-make-regional-navigation-system-navic-accessible-to-civilians-inspace-chairperson-explains-article-115121996 |access-date=2024-11-10 |website=Times Now |language=en}}

Study and analysis for the Global Indian Navigation System (GINS) was initiated as part of the technology and policy initiatives in the 12th FYP (2012–17). The system is supposed to have a constellation of 24 satellites, positioned {{Convert|24000|km|4=0|abbr=on}} above Earth. {{As of|2013}}, the statutory filing for frequency spectrum of GINS satellite orbits in international space, has been completed.{{Cite news|url=http://www.thehindubusinessline.com/todays-paper/tp-economy/global-indian-navigation-system-on-cards/article991761.ece|title=Global Indian Navigation system on cards|date=2010-05-14|work=Business Line|access-date=2017-06-22|language=en}} As per new 2021 draft policy,{{Cite web|title=Indian Satellite Navigation Policy-2021 (SATNAV Policy-2021)|url=https://www.isro.gov.in/sites/default/files/satnav_policy-29.pdf|url-status=live|archive-url=https://web.archive.org/web/20210730141223/https://www.isro.gov.in/sites/default/files/satnav_policy-29.pdf|archive-date=30 July 2021|access-date=3 August 2021}} ISRO and Department of Space (DoS) is working on expanding the coverage of NavIC from regional to global that will be independent of other such system currently operational namely GPS, GLONASS, BeiDou and Galileo while remaining interoperable and free for global public use.{{Cite web|last=Dutt|first=Anonna|date=2021-08-03|title=ISRO to expand reach of navigation system globally: New draft policy|url=https://www.hindustantimes.com/india-news/isro-to-expand-reach-of-navigation-system-globally-new-draft-policy-101627930648368.html|access-date=2021-08-03|website=Hindustan Times|language=en}} ISRO has proposed to Government of India to expand the constellation for global coverage by initially placing twelve satellites in Medium Earth Orbit (MEO).

The constellation consists of 7 active satellites. Three of the seven satellites in constellation are located in geostationary orbit (GEO) and four are in inclined geosynchronous orbit (IGSO). All satellites launched or proposed for the system are as follows:

{{multiple image

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| header = Animation of IRNSS

| image1 = Animation of IRNSS orbit around Earth.gif

| caption1 = Around the Earth

| image2 = Animation of IRNSS orbit around Earth - Polar view.gif

| caption2 = Around the Earth - Polar view

| image3 = Animation of IRNSS orbit - Earth fixed - front view.gif

| caption3 = Earth fixed frame - Equatorial view, front

| image4 = Animation of IRNSS orbit - Earth fixed - side view.gif

| caption4 = Earth fixed frame - Equatorial view, side

| image5 = Animation of IRNSS orbit - Earth fixed - polar view.gif

| caption5 = Earth fixed frame - Polar view

| footer = {{legend2| RoyalBlue | Earth}}{{·}}{{legend2| magenta |IRNSS-1B }}{{·}}{{legend2| lime |IRNSS-1C }}{{·}}{{legend2| Cyan |IRNSS-1E }}{{·}}{{legend2|Gold|IRNSS-1F }}{{·}}{{legend2| OrangeRed|IRNSS-1G }}{{·}}{{legend2| Red|IRNSS-1I}}

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• Bhuvan
• Indian Space Research Organisation
• GPS-aided GEO augmented navigation (GAGAN)
• Quasi-Zenith Satellite System (QZSS)

{{reflist|30em}}

1. {{note|article}} SATNAV Industry Meet 2006. ISRO Space India Newsletter. April – September 2006 Issue.

• [https://www.isro.gov.in/irnss-programme IRNNS programme] {{Webarchive|url=https://web.archive.org/web/20220302041206/https://www.isro.gov.in/irnss-programme |date=2 March 2022 }}
• [https://www.isro.gov.in/SatelliteNavigationServices.html Official Website]
• [https://www.isro.gov.in/IRNSS_Programme.html IRNSS Programme] at ISRO

{{IRNSS satellites}}

{{Indian space programme}}

{{Indian spacecraft}}

{{Satellite navigation systems}}

{{Satellite constellations}}

{{Time signal stations}}

{{Portal bar|Spaceflight|Geography|India}}

Category:ISRO programs

Category:Navigation satellite constellations

Category:2013 establishments in India