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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."
shouldn't have scratched our own satelite project (named Galileo, IIRC)
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Entranced by anime since late summer 2001 and loving it ^_^
Don't like it, but it's the army's stuff. They can degrade it that far if they want to. Don't like it? Send up your own GPS satalites.
Mod point free since 2001
" Users depending on GPS systems may want to do sanity checks on any data "
Which sane person would rely on GPS data for something even as trivial as navigation? Incidentally, how does one check GPS data? Against another GPS??
If you keep throwing chairs, one day you'll break windows....
Last time they turned off the S/A during the war, cheaper that way using off the shelf gps.
You can always have a radio broadcasting the offsets from a known location to compensate.
my associative arrays can kick your hash - TCL
Do they really know how much a captain depends on GPS these days, especially when it comes to passing in and out of harbors? I hope this won't wreck another tanker somewhere.
Let me understand this, the head of a German Autoclub says the U.S. military MAY, I repeat MAY, degrade GPS accuracy. No evidence. Just pure conjecture. Consider that GPS has woven itself into our lives. How, it arguably supports critical functions. I strongly doubt that they will do this. While I understand the world's fears concerning GPS because it is run by the military, I put this article in with all FUD.
But then again, there's not much fairness in this whole debacle.
;)
I'm not about to argue with that kinda military force - only a madman would do that
A slashdotting - you get the stick first and then the carrot !
Apparently the Pentagon sees no compelling reason for an alternative to GPS. Oops, that would be before they checked their GPS units round about now. Oh wait, I forgot, they have their fingers on the buttons, perhaps that why they can't see a compelling reason.
Oops look; those pesky photons might interfere with each other
On the other hand, to be fair, the US could have just degraded the signal without announcing it. At least now ships and planes probably won't be piloted into rocks.
Incidentally, the many billions of dollars of equipment the military is about to blow up in Iraq don't come from nowhere either--they are coming from the check you and I are sending to Uncle Sam on April 15. The war may amount to somewhere between 10% and 20% of our taxes. I hope it's worth it because it sure is a lot of money.
S/A has always been a bit of a farce. It can be circumnavigated (no pun intended) if you use Differential GPS.
Basically, you set one GPS receiver up at a known, surveyed location and program that location into the unit. Then when the receiver trilaterates its position based on the information the satellites provide, it does on-the-fly corrections (You say i'm here, but i know i'm here). It can then use that correction algorithm to correct the positions of other receivers.
Of course doing that part on-the-fly is a bit more difficult (read expensive) because now you have to invest in radio communications back and forth between the two or more receivers - but it's often done. There are even services that have base stations set up across the country that sell a subscription-based service for that purpose.
Most times, survey firms just log the data and correct after-the-fact back in the office from the base station (the differentiator) located in the same area.
All in all, S/A only imposes the error to systems that don't have the capability == money to do DGPS.
There are 01 types of people in this world. Those that understand binary, and me.
I guess we all just pospone that trip to the wilderness to get away from things..
Take a MAP ( remember those things? ) on your next road trip...
After the war the service will return to normal.
Besides, who said we had a right to use GPS anyway?
---- Booth was a patriot ----
GPS is much more important to the US military, which does not have on-the-ground knowledge there. The US should be more worried about the Iraqis jamming GPS signals and other communications.
Of course, so far, it looks like Iraq is pretty feeble militarily. I suspect the war will be over very quickly. Which brings up the question again: why are we going?
In the USian Army we required 100m accuracy for Armor, 10m accuracy for Infantry/dismounted folks. All of the instruction had these tolerances.
...).
Yes, but did you need these tolerences ? For infantry navigation, you usually don't (Except for some extremely bad terrain types, an infantry officer/noncom who loses himself in an 100mX100m sized square won't do any good anyhow
For precise indirect fire, you do, but then again, my guess is that the Iraqi artillery (both light and heavy) positions are already very well measured.
The US army doctrine probably requires these accuracies simply because they can get it relatively cheaply. Nothing wrong with that; in fact that's the correct thing to do. But that does not mean an army can't fight well with less accurate equipment.
Working for necessity's mother.
Well, it seems the US government isn't too comfortable with that and tries (german link) to make (german link) the EU abandon that project. Naturally the EU doesn't like depending on a US-monopoly for such an important system.
"By the way if anyone here is in advertising or marketing... kill yourself." -- Bill Hicks
Since localizing skewed GPS signals is possible... Can the US Military please make it appear to the Iraqi's, that in fact, coordinates of advancing US Forces actually appear to be coming from a country slightly to the North and to the West?
Then, the Iraqi's can send those missiles that they "don't have" straight to their bestest pal...Jacquey-boy.
This was already note here (close to Serbia/Kosovo etc) in the previous US military intervention. Some friends of mine do sailing and had already noted that their GPS devices had gone "crazy". At least this time they issued a warning (then again maybe they had warned back then, but I don't remember).
The reality is that in the time period since S/A was turned off many businesses have become dependent on the GPS. If S/A were to be turned back on worldwide, then that would provide one more reason to oppose the war. COnsidering the current political climate, both in the US and worldwide, I can't see this happening.
Oh Yeah. I forgot. The Europeans have always done such a good job cleaning up.
Kosovo. Thousands of innocents murdered in their own backyard, but they're incapable of bringing themselves to do the right thing, until the U.S. steps in.
Or, perhaps that failure was just a lack of European intestinal fortitude.
It's so typically European. They'd rather have stable despots than the liberation of millions of people. This isn't only a recent development.
The cowardly response to the above will be that stability is better than chaos where millions may starve.
But that's a position that is could only be held by people who've been protected for the last 50 years by the American Taxpayer. A people, I might add, that have for several decades now not known what it's like to live in fear of tyranny.
How many hundreds of trillions of dollars have Americans spent to maintain the current European lifestyle? This is money that was spent on European defense, but ultimately, allowed the Europeans to neglect their own defense spending and focus on domestic needs.
The only reason western Europe has the luxuary of looking down its nose at the U.S. today is that they've essentially been a collection of welfare states of the United States for the last half century.
I for one hope we bring an end to that situation very, very soon. Let the Germans and French worry about their own security. And if the Russian experiment with democracy fails, let's see how critical these same people will be of America then.
Britain aside, NATO has become nothing more than a Welfare program for Western Europe. We stand by them when the Russians are at the door. But where are these folks when we tell them we need them? It's a one-way relationship. One that the American people need to reexamine.
The very threat of military retaliation by the United States allowed western Europe to remain free during the cold war.
Let's see how the European economies do when they have to increase their portion of defense spending, to offset the end of American subsidies. (The only reason European countries have been able to spend so little of their Gross Domestic Product on defense these past five or six decades)
Europeans complain of "The American Empire," as a previous post put it. But I for one would love to see a time arise when my country could go back to being an isolationist one. But ultimately, the same spineless folks who complain about the U.S. today, will be the same ones clamoring for our help tomorrow.
It reminds me of something the comedian David Letterman said after the fall of the Berlin Wall. He had a list of the top 10 things the French were doing to prepare for German reunification.
Number one was "Practicing Blowing kisses while marching backwards."
-dj
- dj
1) Unless you're using GPS for something like surveying (you aren't. admit it.), this doesn't matter. If you can't navigate while hiking/biking/driving/flying/boating with 300 feet of accuracty, then you suck, and you shouldn't be doing it anyway.
2) Are you telling me Iraq needs more than ~100 meters of accuracy to make their attempt at defense? "hmm...I know that gasoline-filled trench was around here somewhere...hmm...where should i drop my torch...duh...."
Come on.
This article says that the DOD has better ways to achieve this end, so you can stop crying. But, if degrading the signal worldwide were the only way to degrade it for the Iraqi military, they would be correct to do so.
"Don't create competing products, because the USA already has made them". What happened to the capitalist ideals about competition in the market?
The official sites to monitor if you're worried:
www.igeb.gov: The IGEB is a senior-level policy making body chaired jointly by the Departments of Defense and Transportation. Its membership includes the Departments of State, Commerce, Interior, Agriculture, and Justice, as well as NASA and the Joint Chiefs of Staff.
Right after 9/11/01, they posted (still there) this: "GPS Selective Availability (SA) has not been used since its deactivation by the President on May 1, 2000. At that time, the United States Government stated that it has no intent to ever use SA again. There has been no change in this policy."
http://www.navcen.uscg.gov/gps/default.htm is the official source for notices to civilian GPS users about schedule satellite outages, etc. They have nothing related to S/A being turned back on, and they certainly would if it were going to happen.
We can jam or dither the civilian code over the theater if we need to.
The comapny I am currently working for (an Env. Engr. firm) requires 15m accurracy for field work. We work with a number of large energy companies, state and federal regulatory bodies and we even are working with DOD and Army Corps of Engineers. If we cannot get good readings, we (and our clients) are out of compliance. Also, doing groundwater studies with 100m to 300m accurracy is also unreasonable.
GPS has become so embedded in our society, that this move just isn't viable anymore, IMO.
Is anyone else in this same situation?
putting the 'B' in LGBTQ+