June 21, 2023
ON MAY 29, THE INDIAN SPACE RESEARCH ORGANISATION (ISRO), in its third blast-off this year, launched NVS-01—the first of India’s second generation of navigation platforms—to add to the Navigation with Indian Constellation (NavIC) constellation’s seven satellites. In addition to being the first launch of a navigational satellite under the new name of NVS, this one surpasses the space agency’s previous mark set during the three pandemic years.
DETAILS OF NVS-01
The 2,232-kilogram navigation satellite, NVS-01, was launched by a Geosynchronous Satellite Launch Vehicle (GSLV) rocket measuring 51.7 metres in height. It has a sophisticated rubidium atomic clock, ‘Made in India’ for exact timing. The smartphones hat are sold in India are currently NavIC-compatible. In the long term, NavIC will develop into a global positioning system (GPS).
GPS & THE KARGIL WAR
Most apps and phones in India that help with navigation use GPS, which is owned by the US government and run by the US Air Force. A news item from Reuters says that India wants to get less of its technology from other countries. Due to events, people may not be able to use GPS. In 1999, India asked the US for GPS data so it could keep track of Pakistani troops during the Kargil War. The US replied in the negative. Since then, ISRO has been working on NavIC. China, the European Union (EU), Japan and Russia all have their own means of finding their way around.
Each of the seven satellites currently in the constellation of the Indian Regional Navigation Satellite System (IRNSS), operationally known as NavIC, weighed considerably less at launch—approximately 1,425 kilogrammes. ISRO’s primary launch rocket, the Polar Satellite Launch Vehicle (PSLV), was utilized by all.
IRNSS-1I, the final satellite in the constellation, was launched in April 2018 to replace a previous, partially defunct satellite. ISRO’s ninth satellite for the NavIC constellation, IRNSS-1I, is actually the eighth as the IRNSS-1H was launched eight months previous to that in August 2017 and was originally intended to replace the older satellite, was lost when the payload’s thermal shield failed to open on time.
RUBIDIUM ATOMIC CLOCK
The second-generation satellite, NVS-01, and the first payload in ISRO’s NVS series, is larger. Besides that, the satellite will have a rubidium atomic clock, which is an important piece of technology that was made in India. ISRO said in a release, “The space-qualified rubidium atomic clock made by the Space Application Centre in Ahmedabad is an important technology that only a few countries have.”
L1 signals will help wearable devices work better. The second generation of satellites will send signals on a third frequency, L1, in addition to the L5 and S frequency signals that the current satellites send on. This will make it easier for other satellite-based guidance systems to work with each other. The L1 frequency is one of the most popular ones used by GPS. This will increase the use of GPS in low-power, single-frequency chips in wearable devices and personal trackers.
MISSIONS THAT LAST LONGER
The missions of the second-generation satellites will last more than 12 years. The current satellites can do their jobs for only 10 years.
But what does the atomic clock on the NVS-01 package have to do with anything? Several of the existing satellites stopped giving location information when their atomic clocks broke. This was the major reason why the replacement satellite was launched in 2018. Since a satellite-based positioning system works by measuring how long it takes for a signal to travel to and from an object using atomic clocks on board, if the clocks stop working, the satellites ca not give exact locations anymore.
ISRO officials say that only four IRNSS satellites are able to provide location services right now. The other satellites can only be used to send messages, such disaster warnings or messages to fishermen about where they might be able to fish.
HOW OLD ARE THE SATELLITES?
This is the second-most important worry after the atomic clocks. IRNSS-1A was sent into space on July 1, 2013, and 1B and 1C were sent into space the next year. The 2018 1H mission which failed was supposed to replace 1A and the three oldest satellites in the system are all close to the end of their 10-year missions. ISRO officials said that at least three new satellites must be put into orbit for the seven-satellite system to keep working well.
NAVIC FOR REAL-WORLD PEOPLE
Experts have criticized ISRO for not focusing on the growth of the user segment until some of the satellites in the constellation were nearing the end of their lives.
Senior fellow at the Manohar Parrikar Institute for Defence Studies and Analyses, said that, because no one was interested in the NavIC system, no receivers were made even though the satellites were sending messages.
A report from the Comptroller and Auditor-General (CAG) of India in 2018 said that, even though the Cabinet approved Rs 200 crore for developing user transmitters in 2006, work on the project did not start until March 2017, by which time seven launches had already taken place.
Now that receivers have been made, NavIC is used for such projects as public car safety, synchronizing power grids, real-time train information systems and protecting fishermen. Last year, Dr Jitendra Singh, Minister of State in the Department of Space, told Parliament that other future projects, such as unmanned aerial vehicles, common alert protocol-based emergency alerts, time dissemination and geodetic network were progressively adopting the NavIC system.
In 2019, NavIC receivers were put into some cell phone chipsets, such as those made by Qualcomm and MediaTek. The Ministry of Electronics and IT is talking to smartphone-makers to get them to make their devices NavIC-compatible.
BENEFIT OF NAVIGATION - DEVICE FOR YOUR AREA
India is the only country with a regional guidance system that uses satellites. There are four global satellite-based navigation systems: the American GPS, the Russian GLObalnaya NAvigationnaya Sputnikovaya Sistema (GLONASS), the European Galileo and the Chinese Beidou. Like India’s GPS-Aided GEO Augmented Navigation (GAGAN), Japan has a system with four satellites that can boost GPS signals across the country.
Once it is fully operational, with ground stations outside of India for better triangulation of signals, NavIC open signals will be accurate to within 5 metres and restricted signals will be even more accurate. GPS data, on the other hand, are only off by about 20 metres. ISRO officials said that work was on to set up ground sites in Japan, France and Russia.
NavIC covers the region of India and an area of up to 1,500 kilometres around it. Even places that are hard to get to should be able to get NavIC readings in this area. NavIC, unlike GPS, depens on satellites that are in a high geostationary orbit. These satellites move at the same speed as Earth, so they always look over the same area.
The NavIC signals come to India at a 90° angle, which makes it easier for them to reach devices even in crowded places, dense forests, or mountains. GPS waves are picked up at an angle over India.