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European Space Agency Developing GPS Rival
nbrimhall writes "The International Herald Tribune has a story here about the European Space Agency's plans to create a alternative to the U.S. controlled GPS. It includes some interesting information regarding the cost and possible contributors (including Canada and Russia)."
I guess for the same reason monopolies make people antsy: the Europeans probably don't like their increasing dependence on a system administered by a single nation, especially one which, from time to time, trumpets "unilateralism".
There might be some concern, too, that the system would be suspectible to terrorist or other hostile action. Two systems might provide the redundancy to salvage a disaster.
The Mongrel Dogs Who Teach
I believe the Soviet Union once launched a system of satellites called GLONASS that worked like GPS. Are they planning to do an upgrade or repair of this system? The GPS FAQ has more information (see section 5.2).
Heck, it's understandable why they'd want to build an alternative GPS; the US Department of Defense could suddenly decide to turn selective availability back on again if they felt like it someday...
Qu'on me donne six lignes écrites de la main du plus honnête homme, j'y trouverai de quoi le faire pendre.
Galileo is attempt to get around the "what if" questions however if the US shuts down the public GPS system, its also going to take out Glonass and any other location system.
When GPS was designed, they added a fudge factor in that would only allow civil recivers to get get a short term fix of about 100m but the military recivers should have been able to get under 10m but because of R&D money on the civil side, the non-military recivers would give much better results than the over priced military ones. With good differental systems you can now get sub meter precision and the fudge factor is pointless and has been turned off. It was the fudge factor that started the Galileo project in the first place.
I don't see Galileo going anywhere. It is a user pay system so are you going to use the euro system where you get to pay $30/yr on top of the reciver or the GPS system where its free thanks to the US tax payers? There will also be the problem that GPS recivers are commodity item and Galileo recivers won't be for at least a decade. Europe would be much better off provide a WAAS compatable sat system than doing their own GPS.
This is due to ionospheric interference. When a radio signal travels through the free electrosn in the ionosphere, it experiences a certain amount of delay. Signals of different frequencies are delayed differently. So in creating the GPS system the military thought of using two signals when the satellites broadcast there info. Called L1 and L2 the military use both signals mesure the amount of delay between them and make corrections for the effect of the ionosphere. The Civilian receivers cannot correct for the ionospheric interference since it only picks up the L1 frequency.
So I guess there is a good, long explanation on
why to invest the capital. Or you could buy the
military reciver.
-Scott
It is said that a child learns wisdom from the parent,
but the truly wise parent learns joy from the child
Currently, when you use a GPS, the longer you stand still the more accurate it gets. This is because it can average out the errors that occur over time. However, once you start moving, it can't do that, because it has a hard time telling movements from measurement errors.
If on the other hand, they included an accelerometer in the GPS unit they could tell with great precision which changes were due to movements, and which were due to errors. Thus, with some algorithm changes, such a GPS unit could continue to refine its measurements to greater and greater precision as long as it was turned on, even if it was moving about.
Ideally, the accelerometer would be integrated on to the same chip as the GPS or Galeon reciever, along with the logic for coorelating the results as well. Accelerometers can be built entirely on-chip, so no extra parts would be needed. I believe modern accelerometers can achieve high accuracy over a very wide range of accelerations using just 2 square millimeters of chip area, so this shouldn't add much to the manufacturing cost.
This would also increase safety in a number of ways. If an airplane in flight lost GPS signal, perhaps due to flying into a low narrow valley, it could continue to navigate electronically for a while (albiert with less precision) using only the accelerometer. If for some reason the GPS or Galeon network became suddenly unavailable due to unforseen circumstances (US goverment getting pissed off, technical issues, bizarre weather, interference, terrorists, etc.), critical systems would have a little extra time to deal with the situation before global positioning equipment failed completely.
Does this make sense to people? Think it's a good idea / bad idea?
(GPS+WAAS is good enough for accuracy in inches, even if they turn SA back on. WAAS will only work in the US though.)
Unlimited growth == Cancer.
Actually, the U.S. Department of Defense has clearly outlined scenarios in which GPS would be locally shut down and/or jammed; Space.com had an interesting story about it earlier this month.
Another reason is the available of ultrawideband technology (UWB). It's really interesting, relatively inexpensive, and can provide tremendously accurate (1 centimeter) positioning.
No, I don't own stock in it or anything like that (although, as a U.S. citizen, I should).
The Europeans have found us out! The GPS is really a source of mind control rays that warp sensibilities. Why do you think Jerry Lewis is so popular in France?
To retaliate they are going to build their own, and make us think the European rock and roll is good, and like warm beer, too!
See http://zapatopi.net/afdb.html for the defence against this dastardly plot!
The military GPS system had an encoded 'noise' generator in it sposition. For civilian use, it was designed to give accuracy within 100m, 95%of the time, and 200m 99% of the time. They also reserved the right to degrade civilian accuracy further (like, within several hundred meters only 50% of the time, or worse) at any time, to keep enemies from using it to lob missiles through windows. The base standard is perfectly adequate for most high-seas navigation, but sucks in tight channels or for any precision operations, like airplane taxiing or highway navigation.
Military GPS recievers had decoders built in, and were accurate to within a couple meters. This diffrence in accuracy was called 'selective availability.' BTW, during the gulf war, the military had a shortage of GPS recievers so they turned selecive availability off and used civilian recievers. Didnt seem to affect security all that much.
To get around the problem, ths US Coast Guard deployed a system called Differential GPS, or DGPS. Basically, they created fixed-position GPS recievers, which continuously compared the position derived from civilian-degraded GPS with a known position, and then broadcast the correction in real time. DGPS recievers applied the correction to the satellite position, and restored ccuracy to about 10-20 meters. In short, one branch of the military, (the coasties) were spending tens of millions to overcome the inaccuaracy included by another branch of the military.
During the Clinton administratioin, it bacame apparent that civilian uses of GPS were becoming signivicant to the economy, so Clinton ordered selective availability turned off (or turned down) to increase civilian accuracy. However, the military still reserves the right to degrade the civilian signal at any time without warning, if they percieve a national security risk.
So, the interest in a European GPS network is at least in part to remove the control from the US military, and remove the hreat of having the system degraded when they may want to use it.
./s here seem to forget the biggest benefit of a Euro-GPS -- redundacy.
You can't even fathom how dependant we are on GPS already. It's amazing.
* Ships use it as a replacement for LORAN (with LORAN being the redundancy).
*The whole telco industry uses it . Rather then sending a sync signal for long-distance serial lines (aka some T-1s, etc) they use GPS (with wire-sync being the redundancy).
* A good hunk of the computer industry uses it. GPS receivers are used for many NTP servers.
* The FAA is looking into using it (as a replacement for thier ground-based radar set up to allow pilots to autonomously plot thier poin-to-point flight plans).
* The military uses it in many ways including the self-guided smart bombs, etc.
We all know that a lot of people and companies do not build in redundancy until the sh*t hits the fan andsomthing goes down. If we loose a few GPS satellites the results for those that were not careful would be catastrophic. Having a second system in place, even at a subscription cost, is VERY valuable.
BTW I highly doubt the miltary would ever shut down civilian access to GPS in anything less then a world war. The US economy is WAY too dependant on it.
The problem with the 'just trust us' approach is that it is difficult to place great trust in a democratic country that no longer bothers to count the votes and is planing to do away with trials, replacing them by tribunals. Meanwhile the Bush admin. has declared that it will unilaterally withdraw from any agreements it finds to be inconvenient - including biggies like the ABM treaty.
The cost is not a major issue, $1Bn is not a huge amount in the EU budget, however it is not a negligible issue. The Brits would certainly not get bothered enough about the risks of a US monopoly, the French on the other hand can be relied upon to get into a galic stew over the issue.
The concern for the EU would be that a future US president might use the GPS selective availability system as a bargaining chip in future trade negotiations. The US has from time to time gone through protectionist cycles and a President Buchannan might well have tried to get his way through various types of blackmail. Or imagine Senator Jessie Helms putting a ridder on an appropriations bill ordering the Admin. to turn off GPS service to any country that does not toe the line on whatever idea the supporter of segregation happened to have that week.
Given the vagaries of the US political process it is not surprising that the dependence on the GPS system is being raised as an issue. It is very unlikely that the EU will go ahead and build a rival system, however it is very likely that the US will respond to the proposals with a set of diplomatic assurances over the use made of selective availabilty. And just as GWB has discovered that the ABM treaty matters after all a future president Buchanan would find that diplomatic assurances are kind of harder to renege on than US unilateralists tend to believe.
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yes, the US military can selectively jam GPS signals, or control the precision of the signals in certain geographic locations.. I actually worked on a project with the NAWC about 6 years ago to do this.. The jammers were small enough that they could fit in something about the size of a suitcase, and be dropped from a plane into enemy territory..
4 7_ STO65096,00.html
In fact, this article suggests that they're doing it now in Afghanistan:
http://www.computerworld.com/storyba/0,4125,NAV