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GPS Accuracy Could Start Dropping In 2010
Posted by
timothy
on Thu May 14, 2009 05:50 PM
from the how-to-blackmail-for-tax-dollars dept.
from the how-to-blackmail-for-tax-dollars dept.
adamengst writes "A US Government Accountability Office report raises concerns about the Air Force's ability to modernize and maintain the constellation of satellites necessary to provide GPS services to military and civilian users. TidBITS looks at the situation and possible solutions."
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Where's Waldo? (Score:5, Funny)
There he is! No, wait...
How about cutting the dead wood? (Score:4, Insightful)
Sounds like a software/project management issue to me. I didn't finish reading the article, but I hope one of their proposed solutions was to fire the incompetent people who can't deliver on-time or within budget.
.02c
just my
Re:How about cutting the dead wood? (Score:5, Insightful)
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Re:How about cutting the dead wood? (Score:5, Funny)
.02Vc (Verizon cents)
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Re:How about cutting the dead wood? (Score:5, Funny)
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You can't touch military spending. (Score:5, Interesting)
They defend "freedom."
I'm all for opening up completely the books of any government subcontractor. If you don't like transparency, then don't take government contracts. It may be tough to police, with companies trying to cheat with subsidiaries, but I think the payoff would be enormous.
On 9/10/2001, Rumsfeld gave a speech about wasteful military spending. Check it out in print [defenselink.mil], or a small piece on CBS [youtube.com]. There was a link to his whole speech years ago - I don't know where that went. In it he states that up to 2.3 trillion dollars is "unaccounted" for, whatever that means. If you read between the lines, he is pushing for privatization of the military. We all know how well that worked out.
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Re: (Score:3, Insightful)
On 9/10/2001, Rumsfeld gave a speech about wasteful military spending
Given his position as Secretary of Defense, he was in the best possible position to fix the woes he spoke of. How'd that work out? It's funny how you fail to fix problems when you have a financial interest in not seeing them fixed. Sure would be interesting to see a full accounting of Rumsfeld's and Cheney's accounts these days, and just how much Northrup Grumman, Lockheed Martin, Boeing, and Halliburton all enhanced their retirements.....
Re:You can't touch military spending. (Score:5, Interesting)
Rumsfeld did have ideas which would have lowered overall spending had they succeeded. However, they flew in the face of thousands of years of military history, and are seen as having been instrumental in what was eventually a rather unceremonious exit. He essentially wanted to go to an all-Special Forces military, with only a few legacy systems for those cases when a couple of massive non-nuclear punches were required. I don't know if he watched Navy Seals one too many times, but nothing replaces boots on the ground when you want to hold ground -- something that Special Forces are not intended to do.
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Just in time for Galileo (Score:5, Insightful)
Re:Just in time for Galileo (Score:5, Funny)
I'm Catholic you insensitive clod! I can't use it!
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Re: (Score:3, Informative)
I'm Catholic you insensitive clod! I can't use it!
Get with the times, you anachronistic clod!
Thanks to his intuition as a brilliant physicist and by relying on different arguments, Galileo, who practically invented the experimental method, understood why only the sun could function as the centre of the world, as it was then known, that is to say, as a planetary system. The error of the theologians of the time, when they maintained the centrality of the Earth, was to think that our understanding of the physical world's structure was, in some way, impose
Re:Just in time for Galileo (Score:5, Funny)
Heh. Naming a bunch of things that orbit the earth after Galileo. Irony :-)
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Re:Best not one system... LORAN, Fuller, Cold War (Score:5, Interesting)
Moral of the story was that using static ground stations like LORAN, this would not have occurred. Anyhow, now ground stations have been dismantled and vessel's receivers scrapped and there is nothing groundbased to replace GPS with should GPS fail. High altitude communications aircraft seem viable; however, there again is a reliance on something that is not physically bolted down and easily fixable.
An interesting footnote is mentioned by Buckminster Fuller [bfi.org] in his 50 year summation masterwork "Critical Path": [easystorecreator.com] on pages 186-7. [amazon.ca] The Americans started their radio-accurate mapping from Compass Island in Penobscot Bay in Maine, and proceeded by radio triangulation to work their way down to South America, across the Atlantic and up Africa to Europe. This was needed for accurately guiding bombers above the clouds, as the ground survey maps were often 10's of miles incorrect.
The Germans had done this as well for Europe and perhaps Russia, so when Berlin fell, the Russians went in early and took the German mapping data. Russia had radio-accurate maps of all of Europe and published data from the US, while the US did not have maps of Russia. This lead to the importance in the cold war of US spy planes and satellites for basic mapping for targeting ICBM's, including as suggested by Fuller a US presence in Iran and Afghanistan as radio triangulation bases. Russia performed massive deceptions of fake cities and so on to perpetuate this information gradient.
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Re:Best not one system... LORAN, Fuller, Cold War (Score:5, Informative)
A friends mom escaped the wreck of a 90ft Fish Packer as it hit the rocks at night in a passage with strong currents due to a problem caused by relying on GPS. It was due to something like how it derived the heading vs the direction of travel or some-such.
Something wrong there. Both LORAN and GPS only give position (GPS gives time too, but that doesn't help here). Direction of travel is determined in both systems by taking the difference in position over a known time interval. GPS can give heading by using the phase difference between receivers on different parts of the vessel, whereas the wavelength of LORAN was probably too long for that to work. Upshot is, a problem involving headings and direction of travel isn't the fault of GPS, and using LORAN would have been no defence. It may have been a problem with the GPS receiver software, but LORAN calculations could go wrong too. Most likely it was a navigator not understanding the systems they had.
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Re: (Score:3, Insightful)
Direction of travel is determined in both systems by taking the difference in position over a known time interval.
Sorry, I should have said velocity is determined in both systems by taking the difference in position over a known time interval. For direction of travel the time interval doesn't matter of course.
How much is actually going to be lost? (Score:5, Insightful)
The real concern is a major solar event - if they're having a big issue replacing one every other year, imagine if a major solar storm took out a dozen at once.
Re:How much is actually going to be lost? (Score:5, Funny)
Maybe people will stop looking at me funny when I carry a compass everywhere.
Maybe they'll stop looking at me even stranger when I tell them which way is north WITHOUT a compass.
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Re:How much is actually going to be lost? (Score:5, Funny)
Maybe people will stop looking at me funny when I carry a compass everywhere.
People used to do the same to me. When someone does, I stab them with the pointy end and draw a circle on their face.
Now they don't look at me funny.
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Re:How much is actually going to be lost? (Score:5, Funny)
Telling North is pretty easy using the stars if available at night or the sun if you are reasonably sure of the season and approximately what time of day it is.
As for the old boyscout adage, I think it should be changed to "Moss always grows on the outside of the tree", that's how useful it is. And of course, a rolling stone gathers no moss, so no matter which way it is rolling, that is no indication of which way is north.
If you are ever going hiking and want to be sure not to get lost, be sure to pack your fiberoptic cable and a shovel. If you get well and truly lost, dig a trench and bury the cable. When the backhoe comes to dig it up, simply follow the backhoe back to civilization.
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Re:How much is actually going to be lost? (Score:5, Funny)
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Re:How much is actually going to be lost? (Score:4, Funny)
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Re:How much is actually going to be lost? (Score:5, Informative)
solar event will cause transient events that will recover in a few seconds.
GPS2F was awarded in the early 90s with a launch date of more than 10 years out. This caused parts issues that significantly magnified design issues. Without going into company secrets, let's just say that bean-counters and engineers fought long and hard. I wonder why Boeing lost GPS3...
If LockMart can't deliver as promised, Airforce can always buy more IIF. After 12-or-so builds currently on contract by Boeing, you figure even the incompetent can get their bugs worked out by then (sans part issues)
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Not a normal event, but an exceptional one (Score:5, Interesting)
A normal event, sure. But a repeat of the 1859 solar flare [wikipedia.org] would likely damage many satellites not in the Earth's shadow at the height of the impact. Is the whole GPS constellation set up to handle that type of event? Or would more than half the satellites go down in a hour?
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Europe to the rescue! (Score:3, Insightful)
Re: (Score:3, Interesting)
Re:Europe to the rescue! (Score:5, Funny)
Oooh, a new acronym!
RAFES - Redundant Arrays of Fucking Expensive Satellites.
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Re: (Score:3, Funny)
No (Score:4, Insightful)
We laughed at the fact that Europe has NOT stated to launch Galileo sats. As of yet, the system is still operational and I can't find any data saying they've even launched a single sat. Last I can see they were supposed to in 2H 2008, but I can't find anything saying they did.
The funny things about Galileo isn't that they are working on their own system. Makes good sense, especially since the US and EU apparently worked out their differences with it and the two systems will work together to give even better results. The funny thing is all the politicing and such going on that is keeping the project in vaporware status for a long time. By the original timeline, the system ought to be up now, and instead it isn't even starting.
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Surveyors are going to start having problems... (Score:5, Interesting)
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No they wont. http://surveyorsnotebook.com/ [surveyorsnotebook.com] If I were to purchase a plot of land ad it had gps coordinates as the buoundary then they would be hiring a certfied surveyor to redo it. GPS is great for maritime , road, and outdoor navigation but is no where near accurate enough for surveys.
Well not if you just walk around with an etrex, but surveyors have more accurate gear than that. Not sure if they still use differential GPS though.
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Btw, IAAS
Re: (Score:3, Insightful)
No, they just have to be consistent.
Re:Surveyors are going to start having problems... (Score:5, Informative)
You don't need military GPS to be that accurate, it can be done with differential phase GPS. See: here [wikipedia.org]. By using a fixed base station at a location with known coordinates, one can expect to see accuracies in the 1 to 2 cm range as long as the receiver is within 10's of km from the base station. There are several manufacturers who make gear that can achieve this level of accuracy, see Leica [leica-geosystems.com], Magellan [magellangps.com], and Sokkia [sokkiacanada.com]. I've been using Leica gear at work mostly, and have see ~1cm accuracy under good conditions pretty consistently. A lot of legal surveying in remote areas is done exclusively with GPS, especially in the northern parts of B.C and Alberta. I've done legal surveys with GPS in the Vancouver area, but getting high accuracy in urban areas is more difficult because of multi-path noise and qoor signal quality from obstructions such as buildings. Also people in the city get mad when you cut down trees to get better reception ;)
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Re:Surveyors are going to start having problems... (Score:5, Insightful)
Doesn't matter.. you aren't going to get better than 10m accuracy without DGPS and 1m with it. Surveys have to be right to centimetres - no GPS can do that.
Yes, they can. They just aren't consumer handheld GPS receivers:
http://www.trimble.com/survey/GNSS-Surveying-Systems.aspx [trimble.com]
They don't give instant position: they accumulate data over a period of time and use that to derive the exact position, usually after correcting it with a comparable stream of data collected from a nearby known reference point.
Under ideal situations the accuracy of GPS equipment can approach 5 millimeter[...] [purdue.edu]
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Re: (Score:3, Informative)
The engineers at Trimble would probably take issue with that statement, since they sell high-dollar ($10~$100k) survey equipment that produces reliable >0.1' accuracy (wikipedia states 20mm as a working number). I worked with equipment in 2003 that was at least 5 yrs old then, and it was that good. The key, as other posters have mentioned, is a base station and some fancy calculations that make it possible.
I'm pretty sure that this equipment has been around since well before the Clinton administration
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That is why surveyors buy surveyor GPS gear. The shit ain't cheap, but when you want centimeter accuracy, you have to buck up.
http://www.trimble.com/survey/GNSS-Surveying-Systems.aspx [trimble.com]
Basically, you set up your own local differential GPS station that sits for a while and figures out its position to a very high degree of accuracy.
You then use very accurate devices capable of sub meter accuracy with time averaging and DGPS, and use the signal from the local station to get even better accuracy than that.
Ge
Re:Surveyors are going to start having problems... (Score:4, Informative)
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Re:Surveyors are going to start having problems... (Score:5, Informative)
The DGPS system at Libby Dam in Montana is accurate to 1-mm vertically:
Performance Monitoring Of Libby Dam With A Differential Global Positioning System [3dtracker.com] UNITED STATES SOCIETY OF DAMS (JUNE 2005)
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Re:Surveyors are going to start having problems... (Score:5, Informative)
Even when trying to take a fix on the same point over time, the margin of error is random. Most of the error is due to propagation delays of the signal. The atmosphere is constantly changing density - the jet stream can raise or lower air pressure between you and satellite #5 at this point in time, or between you and satellite #23 at another point in time. The ionosphere can cause delays or reflections. Nearby buildings, or cars, or airplanes can cause ghost signals. Remember your high school physics teacher who always qualified the the speed of light with the phrase "in a vacuum"? It really makes a difference.
Remember, the GPS satellites are flying in lower earth orbits, and are constantly moving over and around you. They are not fixed relative to you the same way a geosynchronous satellite is (like the DirecTV satellites.) So even if the weather patterns could be precisely measured and figured out, they would be meaningless as soon as the satellite moved - and they're always moving very, very fast.
Differential-GPS improves accuracy by having a mounted GPS receiver at a precisely surveyed point, then transmitting (via FM) the "error difference" between what is derived from the GPS system and the surveyed coordinates. If the error at a particular time is 3 meters at the DGPS antenna, then the error at any other GPS receiver in the area is probably pretty close to 3 meters at that same time (assuming the weather patterns are similar between you and the DGPS antenna.)
You can indeed leave a GPS fixed in a point and average the readings to reduce the margin of uncertainty, but you'll never achieve the high accuracy needed for surveying.
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That's OK. By then GLONASS will be fully operation (Score:3, Informative)
That's OK. By then Russian GLONASS will be fully operational and both the Europeans and the Chinese are thinking of launching their own satellite navigation systems. Out of these three, chances are at least one will be available for the US to use in case of a global conflict.
This is like the Millenium Bug (Score:5, Interesting)
Plenty of people anticipated this, but nobody has given a shit enough about it to do anything substantial. I was first hearing warnings about this years ago. As a programmer, I anticipated the Millenium Bug almost 20 years beforehand, and refused to take those shortcuts that everyone else thought were wise. Back on the GPS Ranch, meanwhile, the EU is busy putting its own superior system in place, in part because they don't want to be dependent upon our system, esp. if and when we fuck up and fail to keep it operational.
Just one more reason to move to Europe.
Re:This is like the Millenium Bug (Score:5, Insightful)
Why move to Europe? I mean, its not like they'll not be restricting the system so that it only works over Europe. Why not just buy a Galileo receiver (when they become available)?
Also, isn't Galileo supposed to be backwards compatible with GPS?
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Re: (Score:3, Interesting)
I was first hearing warnings about this years ago.
Hmm... years ago, Boeing wasn't 3 years behind on launch schedule, and we wouldn't have this issue. If the AirForce had known 3 years ago, they would've exercised some option to build more IIMR builds. Boeing kept on pushing the launch date back, 3 months at a time, and here we are.
Re:This is like the Millenium Bug (Score:5, Funny)
So did I. But some companies still wanted two digit years because it was "too hard" to enter four digit years.
In 1998 I made a killing :-)
Ha! I made my killing in 98, not 1998.
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Hardware can fail? (Score:3, Insightful)
Move along, move along.
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Actually the GPS satellites aren't failing fast enough. It's my understanding that the Air Force has multiple satellite sitting on the ground waiting to launch but the ones on orbit aren't dying fast enough (some of them are already at twice their design life and still going strong)
I was also under the impression that there are currently 29 satellites in orbit, which means that 5 would have to fail before we even get down to a constellation of 24, and they can launch spares before that happens!
Will software defined receivers be common? (Score:4, Interesting)
Are the 3 different GPS systems being proposed (U.S., Galileo, a possibly Russian system) be broadcasting on frequencies close enough to each other that receivers that use all 3 systems will be common and fit into cell phones?
That would be the best outcome : software defined receivers that can pick up a signal from any satellite positioning signal in the sky : GPS, wide area differential GPS, Galileo, everything. Massive redundancy would mean that if you were to go between buildings or even inside buildings, there would be a greater chance that at least some of the satellites were still visible.
Everything that depends on global positioning would work better : from airline navigation systems to X prize landers.
More than GPS (Score:5, Informative)
Here's a listing of all current/proposed global systems. Regional only systems such as IRNSS or Beidou1 are not listed.
GPS - United States - Fully Operation
Galileo - EU/China/Israel/South Korea/Norway/Etc - 2013
Beidou2/Compass - China - 2012?
GLONASS/ - Russia/India - Complete in 2010
Re:Everyone's favorite hobby. (Score:5, Funny)
"What about Goecaching!?" Every nerds favorite hobby could be in jeopardy!
"Everyone" is subjective, "hobby" is misleading and "favorite" is relative... very relative. ;)
"nerd" was right on, however.
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