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It's not just GPS:we have six global navigation satellite systems and they're getting better

If Global Navigation Satellite Systems (GNSS) stopped working, life would quickly become confusing, as we use them for everything from driving directions to updating computer clocks. Even a 13 microsecond satellite clock error in 2016 ended up causing a lot of headaches until it was fixed.

So it's probably a good thing that GPS isn't the only satellite navigation system in existence – Russia, the EU and China all have their own satellite constellations, and there are even smaller regional systems that help make coverage of certain areas more accurate. . In fact, your phone probably relies on two or three different satellite constellations for its location even now!

It's not just about which side of the street you're on:machines will need good location data in the future if they want to navigate a human-sized world, and have multiple GNSS systems to ensure consistent and better availability. accuracy is important. When one of them gets an upgrade, the whole world could benefit. So who are the stars show here?

GPS – Global Positioning System (USA)

It s not just GPS:we have six global navigation satellite systems and they re getting better

The Soviet Union won the space race, but America won the GNSS race, no matter what. GLONASS, Russia's answer to GPS, only started to rise in 1982. It is less accurate than at more central latitudes (about three to eight meters) but has better coverage at northern and southern latitudes, such as Russia built it, you know, Russia. As the second oldest system, it is also the second most common, and many phones and other devices use it alongside GPS.

Galileo (European Union)

It s not just GPS:we have six global navigation satellite systems and they re getting better

In the early 2000s, the EU decided to launch its own constellation of GNSS satellites in order to reduce its dependence on the United States and Russia, in case something happened to one of these services or both. Thus, Galileo was born, and it is ready for full operation by 2020. It offers accuracy up to one meter for regular users and up to one centimeter for paid commercial users. Many phones and other devices have also started using this system, some with dual-band receivers that can reach up to thirty centimeters in accuracy.

BeiDou (China)

It s not just GPS:we have six global navigation satellite systems and they re getting better

At this point you can't really call yourself a major world power without your own GNSS system, so naturally China has jumped into the game with its own BeiDou constellation, made up of thirty-five satellites which should provide precision about a meter. for ordinary people and even less for specialized users. As many phones are made in China, support for the system quickly took off and many manufacturers started using BeiDou alongside the other three systems.

Regional Systems

All major satellite systems have global coverage since their satellites orbit the entire globe. However, they do not always provide the most accurate positioning data, which is why it is increasingly popular for countries to launch additional satellites positioned specifically to provide better data in certain areas. So far we have:

It s not just GPS:we have six global navigation satellite systems and they re getting better

  • QZSS (Japan):This system ensures that there are always satellites above Japan, which is mainly useful due to high-rise buildings blocking signals from shallow angles. It also serves other countries that fall within its orbital trajectories.

It s not just GPS:we have six global navigation satellite systems and they re getting better

  • NaviC / IRNSS (India):This is India's regional satellite project, consisting of several satellites on orbital paths that take them around India and its environs. They only provide an accuracy of 10 meters for civilians, but can go down to 0.1 meters for Indian military and other users.

How to know which systems I use?

At this point, you might be curious what's going on inside your GNSS chip! Fortunately, there are apps to help you.

It s not just GPS:we have six global navigation satellite systems and they re getting better

The ultimate GNSS testing app is GPSTest (Android). That might sound like a lot of data, but the flags on the left side will tell you if you're picking up US, European, Russian, or Chinese signals, as well as smaller regional systems. If there is a “U” in the “Flags” column, it means that this satellite is used by your phone to calculate its position. Sorry, iPhone users – Apple obfuscates satellite data, so there's no app for you.

It s not just GPS:we have six global navigation satellite systems and they re getting better

GNSS View (Android/iPhone). It won't actually tell you which satellites your phone is using, but it's great if you want to know the total number of GPS satellites visible in your section of the sky to get an idea of ​​what your phone can and can't use. . My phone, for example, can pick up GPS, Galileo, GLONASS, QZSS and NavIC, but BeiDou does not show up at all, although several satellites are visible in my area.

So when can I get centimeter-accuracy?

You've probably noticed that many of these systems say they're able to pinpoint locations within centimeters, so why are you stuck with a five-meter GPS? There are actually several reasons:

  • Historically, the equipment needed to obtain high-precision data was difficult to fit into phones. This is changing, however, and the growing number of satellite constellations and new GNSS chips are getting a bit better.
  • Many countries log the most accurate location data for governments, military or paying customers. Centimeter accuracy is available, but not for the public.

However, with the increasing number of navigational satellites in the sky and recent innovations in GNSS chip technology, your phone's location will only become more accurate in the years to come.