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United States has the capability to degrade or deny GPS based on location. Russia has also demonstrated the ability to spoof GPS signals. Either is a likely cau

by bagels 5y ago

United States has the capability to degrade or deny GPS based on location. Russia has also demonstrated the ability to spoof GPS signals. Either is a likely cause here.

miohtama 5y ago
What would be the United States's interest to mess up with GPS now?
- bagels 5y ago
  To deny access to Russia is one reason. Not saying it's the only reason, or that it's not more likely that Russia has done this.
  - brandmeyer 5y ago
    Its a stupid reason. Russian military equipment uses GLONASS. Granted, GLONASS is just barely limping along, but it does work.
    - RobertMiller 5y ago
      It's possible that GLONASS isn't working well for them for some reason. They've been using relatively few precision munitions. And of those few, many of them them seem to be missing by quite a lot. Some of the ballistic missiles they threw at runways look like they were probably under inertial guidance, judging by how badly they missed.
- noughtme 5y ago
  Jamming and spoofing GPS poses less risk than imposing a no fly zone.
  - nosianu 5y ago
    > a no fly zone. Uhm... Finland is several countries north of Ukraine. This is about the eastern Baltic region. I guess you are referring to the rejected NATO-maintained no-fly zone over Ukraine? Or do you mean a no-fly zone imposed by Russia for its Baltic region neighbors?? > According to reports, the interference isn't limited to Finland but also affects Poland, Lithuania, Latvia, and the broader Baltic region. Also, a jammed GPS has little impact on flying, especially not on Russian military flying. They have their own system GLONASS (https://en.wikipedia.org/wiki/GLONASS https://en.wikipedia.org/wiki/GLONASS).
deleted 5y ago
[deleted]
Bronze_Colossus 5y ago
The United States do not have the ability to degrade or deny a gps signal based on location unless that particular location has a physical GPS jammer. I don't see what the US would gain from disrupting civilian airtraffic navigation. Just stop with your "either is a likely cause here"-spiel.
- octoberfranklin 5y ago
  In a major departure from previous GPS designs, the M-code is intended to be broadcast from a high-gain directional antenna, in addition to a wide angle (full Earth) antenna. The directional antenna's signal, termed a spot beam, is intended to be aimed at a specific region (i.e., several hundred kilometers in diameter) and increase the local signal strength by 20 dB (10× voltage field strength, 100× power). A side effect of having two antennas is that, for receivers inside the spot beam, the GPS satellite will appear as two GPS signals occupying the same position. https://en.m.wikipedia.org/wiki/GPS_Block_III#Military_(M-code) https://en.m.wikipedia.org/wiki/GPS_Block_III#Military_(M-co...
  - T-A 5y ago
    That's an ability to improve service for users of M-code receivers, which AFAIK are only available to the military (and it's new technology, so I'd expect it to be unsupported even by most military receivers currently in use).
    - octoberfranklin 5y ago
      The M-code is transmitted in the same L1 and L2 frequencies already in use Nothing says that they have to transmit M-codes from the spot beam antenna. In fact, since the M-codes are hardly used, it's pretty certain they're using that antenna for something else. How very convenient that those antennae are designed to transmit on the same frequency as the "ordinary" antenna.
      - T-A 5y ago
        > The M-code is transmitted in the same L1 and L2 frequencies already in use Let's quote the whole thing, shall we? The M-code is transmitted in the same L1 and L2 frequencies already in use by the previous military code, the P(Y) code. The new signal is shaped to place most of its energy at the edges (away from the existing P(Y) and C/A carriers).
kroeckx 5y ago
In 2000, Bill Clinton has banned the use of Selective Availability. Newer satellites, decided in 2007, first launched in 2018 don't even have the capability anymore.
- Rebelgecko 5y ago
  This is different than selective availability, which kept the signals on at regular power but rounded off numbers/degraded them them. Starting with GPS 3 (or maybe even Block II-F?), the satellites have multiple antennas so they can just turn themselves on and off for specific regions. No cap. They can also adjust the SNR more granularly for the individual signals.

by bagels 5y ago

United States has the capability to degrade or deny GPS based on location. Russia has also demonstrated the ability to spoof GPS signals. Either is a likely cause here.

miohtama 5y ago

What would be the United States's interest to mess up with GPS now?

bagels 5y ago
To deny access to Russia is one reason. Not saying it's the only reason, or that it's not more likely that Russia has done this.
- brandmeyer 5y ago
  Its a stupid reason. Russian military equipment uses GLONASS. Granted, GLONASS is just barely limping along, but it does work.
  - RobertMiller 5y ago
    It's possible that GLONASS isn't working well for them for some reason. They've been using relatively few precision munitions. And of those few, many of them them seem to be missing by quite a lot. Some of the ballistic missiles they threw at runways look like they were probably under inertial guidance, judging by how badly they missed.
noughtme 5y ago
Jamming and spoofing GPS poses less risk than imposing a no fly zone.
- nosianu 5y ago
  > a no fly zone. Uhm... Finland is several countries north of Ukraine. This is about the eastern Baltic region. I guess you are referring to the rejected NATO-maintained no-fly zone over Ukraine? Or do you mean a no-fly zone imposed by Russia for its Baltic region neighbors?? > According to reports, the interference isn't limited to Finland but also affects Poland, Lithuania, Latvia, and the broader Baltic region. Also, a jammed GPS has little impact on flying, especially not on Russian military flying. They have their own system GLONASS (https://en.wikipedia.org/wiki/GLONASS https://en.wikipedia.org/wiki/GLONASS).

deleted 5y ago

[deleted]

Bronze_Colossus 5y ago

The United States do not have the ability to degrade or deny a gps signal based on location unless that particular location has a physical GPS jammer. I don't see what the US would gain from disrupting civilian airtraffic navigation. Just stop with your "either is a likely cause here"-spiel.

octoberfranklin 5y ago
In a major departure from previous GPS designs, the M-code is intended to be broadcast from a high-gain directional antenna, in addition to a wide angle (full Earth) antenna. The directional antenna's signal, termed a spot beam, is intended to be aimed at a specific region (i.e., several hundred kilometers in diameter) and increase the local signal strength by 20 dB (10× voltage field strength, 100× power). A side effect of having two antennas is that, for receivers inside the spot beam, the GPS satellite will appear as two GPS signals occupying the same position. https://en.m.wikipedia.org/wiki/GPS_Block_III#Military_(M-code) https://en.m.wikipedia.org/wiki/GPS_Block_III#Military_(M-co...
- T-A 5y ago
  That's an ability to improve service for users of M-code receivers, which AFAIK are only available to the military (and it's new technology, so I'd expect it to be unsupported even by most military receivers currently in use).
  - octoberfranklin 5y ago
    The M-code is transmitted in the same L1 and L2 frequencies already in use Nothing says that they have to transmit M-codes from the spot beam antenna. In fact, since the M-codes are hardly used, it's pretty certain they're using that antenna for something else. How very convenient that those antennae are designed to transmit on the same frequency as the "ordinary" antenna.
    - T-A 5y ago
      > The M-code is transmitted in the same L1 and L2 frequencies already in use Let's quote the whole thing, shall we? The M-code is transmitted in the same L1 and L2 frequencies already in use by the previous military code, the P(Y) code. The new signal is shaped to place most of its energy at the edges (away from the existing P(Y) and C/A carriers).

kroeckx 5y ago

In 2000, Bill Clinton has banned the use of Selective Availability. Newer satellites, decided in 2007, first launched in 2018 don't even have the capability anymore.

Rebelgecko 5y ago
This is different than selective availability, which kept the signals on at regular power but rounded off numbers/degraded them them. Starting with GPS 3 (or maybe even Block II-F?), the satellites have multiple antennas so they can just turn themselves on and off for specific regions. No cap. They can also adjust the SNR more granularly for the individual signals.