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U.S. May Reduce Non-Military GPS Accuracy
ward99 writes "The U.S. government may be degrading GPS satellite signals, to cripple Iraqi forces' ability to use those systems
during the war. This could potentially reduce accuracy from ~3 meters to
over ~100 meters. Users depending on GPS systems may want to do sanity checks on any data returned by those systems during the war. The U.S.
will do this by increasing the inaccuracies on the civilian C/A code, turning back on S/A (Selective Availability), by having the satellites deliberately and randomly return inaccurate information on where they are. S/A degrades GPS
accuracy to only 100 meters 95 percent of the time and 300 meters the other 5 percent of the time. This will not effect the military P code."
My guess is that for high-precision locations, the Iraqis already measured them with high accuracy, while for, say, infantry navigation all you really need is 100m accuracy. (Even less for armored forces, of cource)
And given the air threat, I also doubt their forces will change their localtions too much; if it's camouflaged enough to survive the initial attacks, it will probably stay put.
Working for necessity's mother.
Civilian planes use GPS, don't they?
What about other critical systems like police, ambulance, fire brigades and so on??
There are plans for building a similar system to GPS in Europe so that we are not too much depending on the american empire. The following page nicely explains the concept. More is available here . This is technically very interesting and should open up new possibilities for navigation. Furthermore being constructed jointly by many partners and nations we can be reasonably sure that it can not be compromised by one weak leader.
Googlefight "Slashdot Troll" against "BSD is dying" 303:229. BSD thus cant die.
a) A sane person would rely on GPS because they may not be very good with compass and map, or they may have cordinates for something not marked on a map. When driving at speed the margin of error is negligible, and it enables you to navigate through featureless terrain such as desert playa which are impossible to use a map in.
v)Well...I would walk to a point which I knew the exact location of and then do 10 or 15 GPS location checks to see what the margin of error was.
Did you really not know these answers or am I just feeding a troll?
"To any truly impartial person, it would be obvious that I am right."
There was a big discussion on one of the GPS newsgroups about this very fact - at the time of the last gulf war, civillian GPS units were cheaper, more plentiful, and had more features that the troops wanted/required than the more cumbersome military GPS units.
One of the soldiers was talking about it in the group and basically said the military units were limited to showing long/lat and doing goto-waypoint distance/direction operations. At the same time, civillian units had mapping capabilities, easy to use graphic displays, and were about 1/2 the size.
As other posters have said, it's possible to adjust the SA signal geographically, so they could degrade the signal in the middle east without changing anything in north america. This is the first step that seems logical.
Alternately, they could leave SA off alltogether, and just jam the GPS signal in the area that they are performing operations - the GPS signal is relatively weak and an ECM aircraft could easily block hundreds of miles of GPS reception while flying out of range of ground-based weaponry.
N.
"Nothing strengthens authority so much as silence." - Charles de Gaulle
Even if it was, it would still remain under the control of the Russian military, just as GPS is under the control of the Pentagon.
The whole point (well, one of the major ones, anyway) of Galileo was to create a network which wouldn't be under military control, and so could be relied upon not to be switched off at inconvenient moments.
I rather like to idea of getting a bunch of people together - going round to military HQ and saying - "can we have our bomb back?"
On the contrary. The Iraqis' biggest weakness in the first Gulf War was their inability to navigate through the open desert. There's very little in the way of navigation aids out there, so it doesn't matter how well you know the country.
GPS is their ticket off of the roads, allowing them to do what we did-- go right through the unposted desert. My question is how much this signal will be degraded, and whether it will seriously hinder efforts at desert navigation.
I don't think the army is too worried about DGPS. It would solve the civian problems of accessing accurate GPS data, but not the military problems. Why? Because the DGPS station would need to have a transmitter, and it would have to remain at a very precisely fixed geographic location, and transmitters don't last long in war - especially if they are in fixed locations.
I know the US is actively looking to find ways to deny potential enemies access to 3rd party satellite services. If the EU launces their own GPS system, they would be expected to play ball with the US and turn it off in areas where the US military is operating. If they don't the satellites could be considered a military device (since they would be used by a military), and they would probably be jammed at the least, and if that doesn't work then they could be targetted. I'm guessing most corporations that own satellites would just play ball - those satellites cost big money and I doubt their insurance protects against US anti-satellite weapons. Government-owned satellites might be a different story - depending on whether the foreign government wants to make the political move of standing up to the US.
Keep in mind that providing targetting data to a military is hardly a neutral stance. If the US provided military GPS receivers to Chechen rebels, you can bet the Russians would be ticked.