NavIC- India’s own GPS
Agenda
- Overview
- Introduction
- Why was NavIC developed?
- Development
- Architecture (Ground Segment + Space Segment + User Segment)
- Services and Performances
- Commercialization of NavIC
- Accuracy
- Who all are authorised to use IRNSS?
- Applications of IRNSS
- Significance
- NavIC vs GPS vs Beidou vs Glonass vs Galileo vs QZSS
- Limitations
- Conclusion
Overview
Abstract NavIC ( Navigation under Indian constellation ) is an operational name of IRNSS (Indian Regional navigation satellite system) a self-governing regional satellite navigation system that offers precise real-time positioning and timing services.
Note: Down the IRNSS and NavIC refer to the same.
The name NavIC was proposed by our Honourable prime minister of India, Narendra Modi in honour of our country’s fishermen and sailors.
It is a constellation of 7 satellites in an orbit altitude of 36000 km above the earth’s surface, covering the whole of India along with an extension of 1500 km across the boundaries, which even cover up some of our neighbouring countries as well. The constellation is in orbit as of 2018, It provides us two different types of services:
- SPS (Standard Positioning system)
Accuracy Range: 15–20 ms
For: Common people - RS (Restricted Services)
Accuracy Range: 5–10 ms
For: Authorised User( military applications)
Introduction
IRNSS is a regional satellite navigation system owned by the Indian government. The system is being developed by ISRO. The ISRO and its commercial arm Antrix Corporation Ltd. are set to commercialize India’s regional navigation satellite system NavIC.
It covers India and a region extending 1,500 km (930 mi) around it, with plans for further extension. An extended service area lies between the primary service area and a rectangle area enclosed by the 30th parallel south to the 50th parallel north and the 30th meridian east to the 130th meridian east, 1,500–6,000 km (930–3,730 mi) beyond borders.
The system currently consists of a constellation of seven satellites, with two additional satellites on the ground as stand-by. It has been certified by the 3rd Generation Partnership Project (3GPP), a global body for coordinating mobile telephony standards.
Adding to its list of achievements, India became the fifth country (At the time it came) in the world to have its independent regional navigation satellite system NavIC developed by ISRO. Nowadays 6 countries have their own navigation system including India. Other countries are the US, Russia, Europe, Japan, and China. I will tell you more about this down the line.
Why was NavIC developed?
NavIC 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 the Indian request for Global Positioning System (GPS) data Kargil region.
India could have had access to vital information had the US shared its GPS. Therefore, the Indian Government approved the project in 2013. On May 28, 2013, the Indian Space Research Organization (ISRO) opened a new facility within their Deep Space Network (DSN) as a part of the project.
During its 102nd session held virtually (4 to 11 November 2020), the Maritime Safety Committee (MSC) of IMO approved IRNSS as a World Wide Radio Navigation System (WWRNS). As per experts, it has the potential to replace the US-owned Global Positioning System (GPS) in the Indian Ocean extending up to approximately 1500 km from India’s boundary.
Development
As part of the project, the ISRO opened a new satellite navigation centre within the campus of ISRO Deep Space Network (DSN) at Byalalu, in Karnataka on 28 May 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.
The total cost of the project was expected to be ₹14.2 billion (US$186 million), with the cost of the ground segment being ₹3 billion (US$39 million), each satellite costing ₹1.5 billion (US$20 million) and the PSLV-XL version rocket costing around ₹1.3 billion (US$17 million). The planned seven rockets would have involved an outlay of around ₹9.1 billion (US$119 million).
From 1 April 2019, the use of AIS 140 compliant NavIC-based vehicle tracking systems was made compulsory for all commercial vehicles in India.
In 2020, Qualcomm launched four Snapdragon 4G chipsets and one 5G chipset with support for NavIC. NavIC is planned to be available for civilian use on mobile devices after Qualcomm and ISRO signed an agreement.
Architecture (Ground + Space + User)
Ground Segment: The ground segment is responsible for the maintenance and operation of the IRNSS constellation. The IRNSS Ground Segment consists of the following:
1- IRNSS Spacecraft Control Centre (SCC)
2- IRNSS Navigation Centre (INC)
3- IRNSS TTC & Uplinking Stations (IRTTC)
4- IRNSS Range and Integrity Monitoring Stations (IRIMS)
5- IRNSS Timing Centre (IRNWT)
6- IRNSS CDMA Ranging Stations (IRCDR)
7- Laser Ranging Station (ILRS)
8- Data Communication Network (IRDCN)
Space segment: IRNSS is a constellation of eight satellites in space, out of which 7 are currently active. These satellites are positioned approximately 36,000 km away from Earth and are as follows:
- IRNSS-1A
- IRNSS-1B
- IRNSS-1C
- IRNSS-1D
- IRNSS-1E
- IRNSS-1F
- IRNSS-1G
User Segment: The IRNSS User Segment consists of dual-frequency IRNSS receivers (L5 and S-band frequencies) or single-frequency IRNSS receivers (L5 or S-band frequency).
Services and Performances
There will be two kinds of services:
- Special Positioning Service (SPS)
- Restricted Service (RS)
Both services will be carried on L5 (1176.45 MHz) and S-band (2492.028 MHz). The data structure for SPS and RS takes advantage of the fact that the number of satellites is reduced to 7 instead of the 30 used in other constellations. The clock, Ephemeris, and Almanac data of the 7 IRNSS satellites are transmitted with the same accuracy as in legacy GPS (US), GLONASS (Russia) & Galileo (European Union) navigation systems.
The Performances expected for the IRNSS system are Position accuracy of around 20 m over the Indian Ocean Region (1500 km around India) and less than 10m accuracy over India and GSO adjacent countries.
The results show the potential of NavIC as an alternative navigation system for India and the neighbouring countries in south and south-east Asia, and over an economically important area containing major sea routes. Even in constrained-visibility conditions, NavIC with its typical constellation design can offer a seamless navigation solution over a large region of the globe; the unique S-Band NavIC signal supports enhanced accuracy for stand-alone operation.
Commercialization of NavIC
Antrix, the commercial arm of ISRO has floated two separate tenders to identify industries that can develop dedicated NavIC-based hardware and systems.
NAVIC is being commercialized for the following reasons:
- Navigation (Aerial, marines and terrestrial)
- Maps (Charting, Plotting and Geodetic data capture
- Disaster Management
- Fleet Management and Vehicle Tracking (important during mining and transport operations)
- Mobile phone integration
- Precise timing (useful for power grids and ATMs)
The Ministry of Road Transport and Highways has mandated that all national-permit vehicles must have such tracking devices. As a pilot, many fishing boats have been fitted with these devices that have a unique texting facility.
The 3GPP certification will allow multiple possibilities for further commercialization of NavIC.
Accuracy
The system is intended to provide an absolute position accuracy of better than 10 metres (33 ft) throughout the Indian landmass and better than 20 metres (66 ft) in the Indian Ocean as well as a region extending approximately 1,500 km (930 mi) around India.
The Space Applications Centre 2017 said NavIC will provide standard positioning service to all users with a position accuracy up to 5 m. The GPS, for comparison, has a position accuracy of 20–30 m. Unlike GPS, which is dependent only on L-band, NavIC has dual frequencies (S and L bands). When a low-frequency signal travels through the atmosphere, its velocity changes due to atmospheric disturbances. The US banks 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 India’s case, 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 is more accurate than GPS.
Who all are authorised to use IRNSS?
At present, all merchant vessels including small fishing vessels are authorised to use the IRNSS. At least 2,500 merchant vessels are there in the Indian waters which are authorised to use this system. The IRNSS is a modern and more accurate navigation system that provides accurate position information to assist ships in the Indian Ocean.
Applications of IRNSS
1- Terrestrial, Aerial and Marine Navigation
2- Disaster Management
3- Vehicle tracking and fleet management
4- Integration with mobile phones
5- Precise Timing
6- Mapping and Geodetic data capture
7- Terrestrial navigation aid for hikers and travellers
8- Visual and voice navigation for drivers
Significance
It gives real-time information for 2 services i.e standard positioning service open for civilian use and Restricted service which may be encrypted for authorised users like for military.
India became one of the 5 countries having their own navigation system like GPS of the US, GLONASS of Russia, Galileo of Europe and BeiDou of China. So India’s dependence on other countries for navigation purposes reduces.
It will help scientific & technological advancement in India. It is important for the country’s sovereignty and strategic requirements.
In April 2019, the government made NavIC-based vehicle trackers mandatory for all commercial vehicles in the country in accordance with the Nirbhaya case verdict.
Also, Qualcomm Technologies has unveiled mobile chipsets supporting NavIC
Further with extensive coverage, one of the stated future uses of the project includes sharing the project with the SAARC nations. This will help in integrating the regional navigation system further and a diplomatic goodwill gesture from India towards countries of the region.
It will have a less accurate extended service area over the regions enclosed by latitude 30º south to 50º north, longitude 30º east to 130º east. This region will cover all of South East Asia except parts of Japan, northwest Australia, the Middle East, China and Mongolia, East Africa, and Madagascar.
Limitations
According to recent reports, one drawback that came into the light is that NavIC signals might get affected by out-of-band interference due to Wi-Fi signals and LTE as both of them shares the same S-band frequency and are close to each other, especially Wi-Fi transmission.
Conclusion
India, setting up an indigenous regional navigation system, grabbed the post of 5th country in the world to have one of their own. This is one big contribution to the making of Digital India.
India felt the need of having its own positioning system, after what happened in the Kargil war in 1999, when
U.S. refused to share their GPS geo-locations of the enemies in our territory, but even then, we managed to emerge victorious over them, at last. A cold betrayal leads to the innovation of something stronger and with more accuracy, i.e. NavIC should be used to propel technological innovations that will make India in particular and South Asia, in general, to be less reliant on technological imports from other foreign countries. ISRO has once again proved its technological prowess by developing the satellite navigation system in a record time of 3 years while the Americans and Russians took more than a decade to do the same.
Happy Reading!!!
