Saturday , October 23 2021

If the US turned off the GPS today, you might not even notice it on your phone – Živě.cz


Almost twenty years ago and over ten billion euros, a great European adventure began, culminating in the public launch of the Galileo satellite navigation system in December 2016. Yes, Galileo! That you have already forgotten him?

It is no wonder that Galileo has become commonplace and that the European satellite navigation system has added a host of others that almost every phone supports today.

Galileo satellite navigation system

  • Operator: The European Union
  • Satellites: 22 in operation, 2 test
  • Orbit: 1 km km
  • Accuracy in full deployment: 1-2 m (* open service), 1 cm (HAS – High Accuracy Service)
  • Cost: 10 billion euros

Each satellite was nicknamed by the winner of the Galileo Drawing Contest. The Czech Republic also has a representative. This is a satellite number E19 (GSAT0103) dubbed David by David Markarjanka. You can watch your current location at

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Galileo Earth Segment – Workplace that controls your complete operation

(* Location estimates of the target device may be more accurate because current receivers combine signals from multiple satellite navigation systems.)

You use Galileo every day

Most of you are already using Galileo every day without knowing it. And also the Russian Glonass, the Chinese Beidou / Compass and, finally, the American Navstar GPS system, whose name we now call similar GNSS systems (Global Ninception sStudio ssystem).

To this end, the European Union has launched a new promotional website,, with a catalog of mobile phones, sports watches and entire chipsets on the market that can handle the signal from our own satellites.

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Qualcomm Snapdragon 636 chipset (right) in Nokia 7.1 from our recent autopsy. Of course this SoC already supports Galileo.

Most of Qualcomm's current Snapdragon chipsets, including the Wear version for smart watches, are on the list. Also exhibited are Samsung's Exynos, Mediatek chipsets, Apple A9 support and Broadcom and Intel GNSS modules.

Multiple systems at once

It was the support of multiple satellite positioning systems that led to the acquisition of a phone, car navigation or sports watch, the first fix (coordinates of a geographic location) usually within seconds after the start and the time we needed to travel. gépéesku stand on a stump and wait for a minute, they have been there for a long time. The Garmin owners of the first models of the eTrex series will surely be right for me.

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The hidden world of the signals of satellite navigation systems. Conventional mobile receivers, etc., receive E1 / L1 signals, and newer chips can also receive E5 / L5 signals simultaneously. Other signals are intended for special applications. Source: ESA Navipedia.

However, not only the search, but also the accuracy and permeability of the signal through the material did not accelerate. I write this article in our editorial center in the midst of a historical urban development. On my desk there is a telephone with active GNSS reception. There are tall buildings in the area, but thanks to the reflections of the satellite signals from their facades and thin ceilings, the signal reaches my desk five meters from the window and the control application on the phone shows a maximum of 10 meters. Something like that was practically unthinkable ten years ago.

Not too long ago, it's not just an American GPS

The entire Galileo system now consists of 22 active satellites and 2 test satellites, which is already a fully operational capability (FOC), which the system is expected to achieve relatively soon. This means that even your cell phone will find the signal from these satellites more and more frequently and will choose from them.

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The basic principle of calculating the position of the observer if the receiver knows exactly where the satellite is and how long the signal is flying from it – then, to where it is.

The position calculation itself is done within a conventional telephone by a navigation coprocessor, which then passes the finished data to the operating system, usually in the form of a NMEA text protocol. Because of this, it is not easy to determine who we thank for a little overkill for knowing where we are – whether Washington, Moscow, Brussels or Beijing.

Brief answer: As a general rule, absolutely everyone.

GPSTest for Android will reveal which satellite systems you're using

If there are dozens of GPS satellites, Galileo, Glonass and others flying somewhere between 20 and 30 thousand kilometers above our heads, the cell phone chip can pick the best of these signals and get a fix quickly, even where it would be impossible with the old receiver.

Which of these signals is now, says Sean Barbeau's GPSTest Android mobile application from South Florida University, which is also recommended by the European Global Satellite Navigation System (GSA), which covers both Galileo and EGNOS. Just to remind you that the GSA is headquartered in Prague.

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List of satellites my cell is receiving. The flag itself indicates the navigation system itself. The "U" in the Status column indicates that the chip used the chip in the position calculation for the last fix. As you can see, GPS is only half that.

Startup application displays a list of available satellites from all supported satellite systems and their basic data. When the chip calculates the current location, additional data is displayed. For example, which of these satellites used the receiver to calculate the last fix.

At the same time, each satellite in the list does not have the flag of the country behind, indicating that it is Navstar GPS (USA), Glonass (Russia), Beidou / Compass (China) or Galileo (European Union). You will find a full description of the application in this PDF document.

Both Galileo and GPS do much more

Can some argue why we do not agree and all together have not released a single globally managed satellite system under the auspices of the UN? Simply because in addition to this basic unencrypted signal – in the case of Galileo is called Open Service (OS) – satellite systems can offer different services encrypted at different frequencies, for example only for the critical infrastructure of its members member), rescue system and commercial customers with greater accuracy and mainly availability.

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Several other applications also distinguish satellite navigation systems. For example, GPS Status, which selects a wheel symbol for GPS, squares for Glonass, a cross for Galileo plus and Beidou / Compass. Green indicates the satellites that the chip used to calculate the position and size of the symbol and then the signal strength.

These advanced signals, which are not available to the general public, have defensive mechanisms against interference and allow very fast trajectory positioning and calculation. In short, a closed encrypted GPS signal that directs an American military missile to the target, and a GPS signal that the receiver on your phone can handle are two different things. In the case of Galileo, Glonass and others, the same applies.

On the other hand, in times of peace, all the players mentioned benefit from mutual opening, and we have dozens of American, European, Russian, Chinese, Japanese, and other satellites in high, almost geostationary orbits that help everyone on Earth, not it matters where we go to the forest of mushrooms, or perhaps to the Adriatic.

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