A new stage of anti-Russian sanctions may be the disconnection of residents of our country from the American GPS satellite navigation system. But almost every mobile phone is connected to it, and we all essentially use its services. How real is this threat – and why, in this case, will the US harm itself much more?
The GPS geo-positioning system has long passed into the category of something taken for granted. Turning on a mobile phone to determine their location, users do not even think about the number and affiliation of satellites providing these coordinates, how this happens and why two decades ago the positioning accuracy was much less than it is now.
And now, as the head of Roscosmos Dmitry Rogozin officially declares, the United States is seriously studying the possibility of disconnecting Russia from the GPS system. As part, of course, of the next anti-Russian sanctions. This threat is taken quite seriously in Russia, and, for example, the Federal Air Transport Agency recommended that airlines prepare for flights without using the American global navigation satellite system (GPS).
How GPS works
To understand the possibility and complexity of disabling the GPS system over one particular country, it is necessary to understand the principle of operation of the system. There are several satellites in orbit in constant motion, emitting a synchronized radio signal. The user's receiver must receive a signal from at least four satellites in order to correctly determine the point at which it is located. Three satellites are not enough, otherwise we will get a point without the "height" value.
The receiver itself in the smartphone or navigator does not emit anything. It only receives the signal, determines how long the signal from which of the satellites has reached it, and based on these calculations determines the exact coordinate of the place.
There is a third component – ground stations located on the surface of the planet. The fact is that the Earth is not a perfect ball, respectively, correction and clarification of the predicted position of spacecraft is required to speed up the operation of the device. This is done by ground stations, they calculate the exact location of the satellites, which is entered in the almanac and sent to the devices. Without ground stations and their constant operation, the accuracy of determining coordinates will decrease. Changing the satellite's orbit will introduce gradually increasing errors in the positioning accuracy.
Now about the number of satellites. In total, 24 spacecraft are required to operate the system. Reducing their number will create places where the geolocation system will work worse than it should. Currently, the GPS system has 32 spacecraft in orbit, GLONASS has 25 (23 are used), there are also global Chinese Beidou and European Gallileo.
Modern chips use signals from all systems at once. It is easy to verify this by installing the GPS test program on a mobile phone: it shows how many satellites and which systems the phone sees and uses in real time.
Is it possible to disable GPS?
To begin with, let's decide what exactly and on what part of the terrain we turn off. Very often, when talking about GPS, they mean not only the American satellite system, but generally use this term to refer to all geo-positioning systems.
It is simply impossible to turn off all systems, including the Russian GLONASS, without starting the third World War and destroying all satellites. Americans can turn off their GPS system. By the way, twenty years ago, the American geo–positioning system had two different radio signals - less accurate for civilian devices and more accurate for military ones.
The military code had a longer duration of the PRN code than the civilian one in order to make it difficult to drown it out and to avoid ambiguity collisions in ranges (for a civilian GPS signal, this ambiguity is about 300 km). The military code was more accurate due to a ten times higher frequency of the modulating code, 10.23 MHz versus 1.023 MHz.
Is it possible to do this over a specific location? No, you can't. Approximately each satellite "delivers" its signal to the surface area of the Earth measuring 4 thousand by 4 thousand kilometers. Therefore, even if you turn off the signal during the passage of spacecraft over the surface of Russia, you will have to leave Europe and many other nearby countries without a normal signal.
Americans can turn off ground stations operating in Russia. Yes, this measure is real. But, as mentioned earlier, it can only lead to a slight decrease in the accuracy of the received signals, and then if the device used works exclusively with the GPS system. Otherwise, due to the signal from other satellites, the system will make the necessary corrections.
There is another option – introducing interference using a ground station. But this can be ensured only at the borders of the country to a small depth and with the help of military electronic warfare units of other countries. But if we try to pull off such a focus on the territory of Russia, we can assume that we are practically facing a "casus belli". After all, such an action can affect not only navigators, both household and, for example, aviation, but also automation systems (automated control systems) in a variety of industries.
Therefore, disabling GPS is an exceptional threat. Moreover, if it is used, it may be more painful for some American systems on the territory of Russia than for ordinary navigators in smartphones. Those, as already mentioned, mostly use all possible systems for greater positioning accuracy.
Yes, the US military from time to time conducts exercises in which, according to the conditions, the enemy destroyed the GPS system, and it is necessary to use inertial coordinate systems. But this is rather training in case of an alleged danger, rather than a real strategy for disabling GPS and subsequent actions in one particular country. In reality, there are very few chances that someone will turn off their system, even on enemy territory - there are too many bad consequences, and the benefits are not obvious. The Russian military will simply continue to use GLONASS.
Because, because we are pilots?
Then why the instruction of the Federal Air Transport Agency "State ATM Corporation" to assist the crews of aircraft when GPS is turned off? Why did the pilots receive a recommendation to immediately notify air traffic controllers of failures, deterioration and abnormal operation of GPS and related avionics? In addition, the agency recommended carriers to assess the risks and limitations caused by malfunctions in the operation of navigation devices and onboard systems using the GPS system. Is it that bad?
The root cause of the order is the message of the EU Aviation Safety Agency (EASA), after February 24, cases of "jamming" and possible substitution of GPS signals (spoofing) became more frequent. They were observed at various stages of flights in the Kaliningrad region, near the Baltic Sea basin countries, in the eastern part of Finland, in the Black Sea, in the Eastern Mediterranean region, Israel, Cyprus, Lebanon, Syria, Turkey and northern Iraq.
It would be strange to associate these events even with the theoretical possibility of preparing for GPS shutdown in Russia or somewhere else. Most likely, it just coincided with threats voiced on both sides about the possibility of disconnection.
Then what to do in this case? Should I be afraid of a possible GPS shutdown? No – for several reasons.
Firstly, a point shutdown of this system is impossible, and an attempt to turn off the signal during the passage of satellites over the territory of Russia will lead to a huge number of problems for Russia's random neighbors on the planet and for the United States itself. And secondly, GLONASS, created at the time and now supported, has become the best vaccination against the serious consequences of such a suicidal decision for the United States. You can sleep peacefully, the navigator in the phone will continue to work properly.
Mikhail Kotov