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It also is kinda misguided. If you have the capability to acquire/build a ballistic missile of that class, you most likely can (will) build your own GPS/GNSS r

It also is kinda misguided. If you have the capability to acquire/build a ballistic missile of that class, you most likely can (will) build your own GPS/GNSS receiver. Hell you can take a software defined radio and make your own software-based GPS receiver that does NOT disable itself at those described thresholds (some folks have done this for extremely high-altitude balloon experiments). Selling it of course is another question.

beerandt 7y ago
People under-estimate how difficult geography/ geodesy/ navigation used to be, pre-NAVSTAR GPS. This difficulty was "built-in" to the military defensive posture/strategy/tactics of many countries, to the extent that simple possession of a GPS receiver was/is a crime. And not a misdemeanor, but a treason level offense. Keep in mind, the programs that evolved into NAVSTAR started in the 50s\60s and the tech specs were pretty much set by 1980, along with the legal framework and military policy regarding it's operation. Ironically, it was some of the systematic weaknesses if the original design that led to it being so much more useful (and accurate) than it was ever intended to be. But it is still a military program, with military style regulations, so it shouldn't be too surprised that some of the 1960's era rules haven't evolved too much. It's more surprising to me that so many of the restrictions have been relaxed. (Even if it's policy playing catch-up practice.)
jjeaff 7y ago
Or even reverse engineer the firmware to remove the restriction. I'm also guessing that there are plenty of Chinese made gps devices that don't have that limitation. Simply because, why bother. Assuming you can find one accurate enough on AliExpress, I'd say there is a good chance it has no special restrictions.
- conjectures 7y ago
  This is also what I would expect the reality of the situation to be, regardless of policy.
  - coldtea 7y ago
    Not to mention that one would assume if someone can make a GPS-guided missile, they can sure as hell alter/find a workable GPS for their purpose... It's not Joe Average will try to make a missile with a GPS from his Garmin watch...
    - angry_octet 7y ago
      But any number of non State actors would. The IRA or ISIS or Hezzbollah for example. They probably don't have the tech capabilities to RE their own GPS firmware, but non-orbiting rocket science isn't that hard. Iron Dome does okay against simple rockets, but a big guided rocket (V2 size) would be a different problem entirely. Obviously drone attacks make use of GPS, and it's a worry to many -- for example, there is frequently GPS jamming when Putin is visiting somewhere.
dhruvmittal 7y ago
Realistically, this is the kind of restriction that's in place to impede the high-frequency & low-capability regime in the space of non-nation-state (or, historically e.g. the 70s, non-peer nation) threats.
- GhettoMaestro 7y ago
  That makes sense. However in today's ever expanding electronics-wonderland, I wonder if it matters anymore.
  - angry_octet 7y ago
    I think, post HK protests, it's going to be harder to order precursor parts from China. All sorts of jamming and drone tech is being used there by both sides. Hopefully we see restraint and mutual de-escalation and we don't see any use of energetics.

beerandt 7y ago

People under-estimate how difficult geography/ geodesy/ navigation used to be, pre-NAVSTAR GPS. This difficulty was "built-in" to the military defensive posture/strategy/tactics of many countries, to the extent that simple possession of a GPS receiver was/is a crime. And not a misdemeanor, but a treason level offense. Keep in mind, the programs that evolved into NAVSTAR started in the 50s\60s and the tech specs were pretty much set by 1980, along with the legal framework and military policy regarding it's operation. Ironically, it was some of the systematic weaknesses if the original design that led to it being so much more useful (and accurate) than it was ever intended to be. But it is still a military program, with military style regulations, so it shouldn't be too surprised that some of the 1960's era rules haven't evolved too much. It's more surprising to me that so many of the restrictions have been relaxed. (Even if it's policy playing catch-up practice.)

jjeaff 7y ago

Or even reverse engineer the firmware to remove the restriction. I'm also guessing that there are plenty of Chinese made gps devices that don't have that limitation. Simply because, why bother. Assuming you can find one accurate enough on AliExpress, I'd say there is a good chance it has no special restrictions.

conjectures 7y ago
This is also what I would expect the reality of the situation to be, regardless of policy.
- coldtea 7y ago
  Not to mention that one would assume if someone can make a GPS-guided missile, they can sure as hell alter/find a workable GPS for their purpose... It's not Joe Average will try to make a missile with a GPS from his Garmin watch...
  - angry_octet 7y ago
    But any number of non State actors would. The IRA or ISIS or Hezzbollah for example. They probably don't have the tech capabilities to RE their own GPS firmware, but non-orbiting rocket science isn't that hard. Iron Dome does okay against simple rockets, but a big guided rocket (V2 size) would be a different problem entirely. Obviously drone attacks make use of GPS, and it's a worry to many -- for example, there is frequently GPS jamming when Putin is visiting somewhere.

dhruvmittal 7y ago

Realistically, this is the kind of restriction that's in place to impede the high-frequency & low-capability regime in the space of non-nation-state (or, historically e.g. the 70s, non-peer nation) threats.

GhettoMaestro 7y ago
That makes sense. However in today's ever expanding electronics-wonderland, I wonder if it matters anymore.
- angry_octet 7y ago
  I think, post HK protests, it's going to be harder to order precursor parts from China. All sorts of jamming and drone tech is being used there by both sides. Hopefully we see restraint and mutual de-escalation and we don't see any use of energetics.