What are various Global Navigation Satellite Systems(GNSS) Around The World?
Did you know GPS, or Global Positioning System, is one of the four Global Navigation Satellite Systems?
Checking out a new coffee house in the town or exploring your dream travel destination like a local is not a big thing now. Wherever you get stuck, you take out your phone, type the destination and navigate to the place. But, have you ever wondered how this tiny mobile device in your hand directs you to every nook and corner? Of course, you know, it is the small GPS chip in the phone which does the magic. GPS provides location and time information anywhere on the earth.
But did you know GPS, or Global Positioning System, is one of the four Global Navigation Satellite Systems? The four global GNSS systems are — GPS (US), GLONASS (Russia), Galileo (EU), BeiDou (China). Additionally, there are two regional systems — QZSS (Japan) and IRNSS or NavIC (India).
Global Positioning System (United States)
GPS is the oldest GNSS system. It initiated its operations in 1978 and was available for global use from 1994.
The need to have an independent military navigation capability drove its innovation. And the US military was the first to realize this. And thus, in 1964, the Transit system was deployed for the purpose. Transit, also known as NAVSAT, worked on the Doppler Effect and provided location information and navigation to missile submarines, surface ship, and hydrographic survey geodetic surveying to the US army. With time, GPS was opened up for public use. Currently, GPS has a 33 satellite constellation, out of which 31 are in orbit and operational. It is maintained by the US Air Force and is committed to maintaining the availability of at least 24 operational GPS satellites. Till date, GPS has launched 72 satellites.
GLONASS (Russia)
Global Navigation Satellite System or GLONASS is the global navigation system of Russia. GLONASS became operational in the year 1993 with 12 satellites in 2 orbits at the height of 19,130 km. At present, there are a total of 27 satellites in orbit, and all are operational. GLONASS is operated by Russian Aerospace Defence Forces and is the second alternative navigational system in operation.
Galileo (EU)
Galileo is European Union’s GNSS constellation, which is being put together by the European Space Agency, and the European GNSS Agency will operate it. Galileo is a global navigation system available for civilian and commercial use. The fully deployed Galileo system will consist of 30 operational satellites and six in-orbit spares. As of now, 22 out of 30 satellites are in orbit. Galileo started offering Early Operational Capability from 2016 and is expected to reach full operational capability by 2020.
BeiDou (China)
BeiDou is the Satellite Navigation System of China. It has a total of 22 Operational satellites in orbit, and the full constellation is scheduled to comprise 35 satellites. BeiDou has two separate constellations, BeiDou-1 and BeiDou-2. BeiDou-1, also known as the first generation, was a constellation of three satellites. It became operational in the year 2000 and offered limited coverage and navigation services, mainly for users in China and neighboring regions. However, Beidou-1 was decommissioned at the end of 2012.
BeiDou-2, also known as COMPASS, is the second generation of the system. It became operational in the year 2011 with a partial constellation of 10 satellites in orbit. The next generation of it is BeiDou-3. The first BDS-3 satellite was launched in March 2015. As of January 2018, nine BDS-3 satellites have been launched. BeiDou-3 is expected to be fully functional by the end of 2020.
QZSS (Japan)
The Quasi-Zenith Satellite System is the regional satellite navigation system from Japan, which is still under construction by the Satellite Positioning Research and Application Center, Japan. As per plans, the QZSS constellation will have seven satellites, out of which four are already in orbit. QZSS is expected to be operational by the end of 2018, where it will provide highly precise and stable positioning services in the Asia-Oceania region. QZSS will be compatible with GPS.
IRNSS ― NAVIC (India)
The Indian Regional Navigation Satellite System (IRNSS), which was later given the operational name of NavIC or NAVigation with Indian Constellation, is India’s regional satellite navigation system. Launched and operated by the Indian Space Research Organisation (ISRO), IRNSS covers India and nearby regions extending up to 1,500 km. All the seven satellites are in orbit, but the first satellite — IRNSS A — is not functioning now since last year ISRO reported that all three atomic clocks have failed.
ISRO’s bid to launch a replacement satellite failed in August 2017 when in a rare occurrence, the heat shield of the launch vehicle failed to separate to release the satellite. Currently, three IRNSS satellites are in the geostationary orbit, and the other four are in geosynchronous orbits. There is still some time before India starts getting its services.
What Navigation Systems Do You Use?
Typically, the GNSS Framework we use differs geographically; thus, it depends on your physical location to determine the GNSS Framework our equipment uses. This means that if you use a smartphone to geolocate something within the American subcontinent, then you are likely to be locked on to the American GPS Satellites, whereas, if you try to geolocate within the Asian subcontinent, you are likely to lock onto either GLONASS or BeiDou systems, depending upon your location within the subcontinent.
Devices present in the South-Asian subcontinent are likely to lock onto NavIC, given they support NavIC, as the framework works much faster and accurately within the proximity of India and its neighboring countries.
Although the above scenarios exist, given that your device supports all the Navigation Frameworks stated above.
Typically in India, most OEMs provide the three most popular navigation systems(namely GPS, GLONASS, and Beidou). However, the introduction of NavIC systems has sparked a new wave of excitement as OEMs race to integrate the NavIC systems in their chipsets, thus making their equipment to be able to geolocate more quickly and more accurately.