Russia does not trust satellite navigation: Revives old land-based radios

1. marts 2022 kl. 15:45
Russia does not trust satellite navigation: Revives old land-based radios
Illustration: Bigstock.
If Russia invades Ukraine, it will probably be without the use of GLONASS satellite system for navigation. Instead, older land-based navigation systems like Loran are being activated, which Europe and the US have retired.
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When Russian planes and military vehicles are deployed in Ukraine, it will probably be without Russia’s own GLONASS satellite system navigation.

This is the assessment of several military analysts and GNSS experts, according to GPS World.

The latest known radionavigation plan from 2019 shows that Russia does not expect to be able to rely on its own GLONASS satellites in the event of a military intervention.

Instead, Russia has maintained the older Chayka navigation system, which was otherwise supplanted by satellite systems in the 1990s.

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Paradoxically, Russia is an expert in manipulating satellite signals from, for example, GNSS and AIS satellites, and is known for being extremely active when it comes to spoofing and jamming satellite signals.

In November, a Russian ghost ship suddenly appeared off Skagen in the wake of a Russian research vessel being detained by Danish authorities.

In Norway, many examples of jamming and spoofing of GPS and Galileo signals have been registered in areas bordering Russia, for example in rescue helicopters. In Syria, it is known that Russia has spoofed signals to mask its activities at secret air bases inside Syria, which has made it difficult to use GPS in Israeli airports.

Since Russia invaded the Crimean Peninsula in 2014, GPS jamming has been regularly recorded in eastern Ukraine.

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GNSS

There are currently four global navigation satellite systems (GNSS).

Russia’s GLONASS. Consists of 24 satellites.
Europe's Galileo with 30 satellites.
USA’s GPS with 31 satellites.
China's BeiDou with 35 satellites.

Revival of retired Loran navigation system

Instead of satellite navigation, it is expected that Russians will use the otherwise obsolete Loran-C system Chayka, which means “seagull” in Russian. It is a land-based system of radio navigation. Loran is an abbreviation of “long-range navigation”—which dates back to World War II—and the current C version dates from 1957.

According to GPS World, Russia has three Loran stations surrounding Ukraine. The three stations should theoretically be able to cover the whole of Ukraine. Illustration: Charles Schue/UrsaNav.

Loran works on the same principle as satellite navigation, by measuring the time difference between a number of transmitters and receivers in the same Loran chain.

The system consists of transmitters in the frequency range between 90 and 110 kHz. According to Dana Goward, president of think tank Resillient Navigation and Timing Foundation, the Russian Chayka system has an output between 200 and 800 kW with effective ranges of almost 1300 kilometres over land and 1600 kilometres over sea.

Besides Chayka, Russians also have a mobile Loran system called Skorpion. However, international knowledge of that system is very limited.

While satellite signals from GPS, Galileo, and GLONASS satellites are relatively easy to block and manipulate due to, among other things, very weak signals, blocking Loran is conversely more difficult. It requires large antennas, not small handheld antennas as is the case with GNSS.

Jamming vs. spoofing

There are essentially two ways to interfere with GPS signals—jamming and spoofing.

As the word jamming suggests, this method completely blocks the signal, and this type of interference is known from, among other things, military bases, where one would not want to allow the enemy to track movements with GPS signals. This is possible because GNSS signals from satellites are relatively weak.

Spoofing is a more advanced interference in which a radio transmitter sends false GNSS signals that make the receiver believe that they are real satellite signals. This is a significantly more complex method of interference, as one must be able to reproduce several GNSS signals in parallel so that the receiver does not detect that they are false signals.

According to GPS World, Russia has three Chayka stations that surround Ukraine, which should provide coverage throughout Ukraine with a navigation accuracy of between 20 and 50 meters. If Russians have a so-called eLoran system, which is an upgraded version of Loran, they may possibly get up to 5-to-10-meter accuracy.

In 2010, the USA pulled the plug on Loran, while France phased out the Danish Loran-C station Eiðe in the Faroe Islands in January 2016. This means that since 2016, no Loran systems have been in operation in the USA and Europe.

Conversely, Russia, China, and Iran have invested in upgrades to Loran systems in recent years.

Anti-satellite test

In addition to jamming and spoofing GNSS signals, Russia demonstrated a few months ago that it is also ready to move warfare into space, where satellites have now become potential targets.

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In November, Russia conducted a mission that drew extensive attention, testing the new anti-satellite technology ASAT. It was conducted against an inactive Soviet satellite, Tselina D.

According to the Russians, the destruction of the Soviet satellite should be evidence that they are now able to get rid of active GPS satellites. However, there is no sign that Russia intends to go through with that threat, as that would amount to a direct attack on NATO.

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