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Galileo: Europe's Version of GPS Reaches Key Phase

Soulskill posted about 2 years ago | from the not-yet-persecuted-by-the-catholic-church dept.

EU 328

another random user sends this quote from the BBC: "The third and fourth spacecraft in Europe's satellite navigation system have gone into orbit. The pair were launched on a Russian Soyuz rocket from French Guiana. It is an important milestone for the multi-billion-euro project to create a European version of the U.S. Global Positioning System. With four satellites now in orbit — the first and second spacecraft were launched in 2011 — it becomes possible to test Galileo end-to-end. That is because a minimum of four satellites are required in the sky for a smartphone or vehicle to use their signals to calculate a positional fix."

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Chicken::egg. (0)

Anonymous Coward | about 2 years ago | (#41646537)

Are there any consumer gear that can receive Galileo?

Re:Chicken::egg. (4, Insightful)

_merlin (160982) | about 2 years ago | (#41646667)

They'll arrive. There are already devices that can receive both Soviet GLONASS and GPS (e.g. Galaxy SIII) to get better positional accuracy. Soon the new devices will receive Galileo as well, for triple redundancy and improved accuracy.

Re:Chicken::egg. (3, Interesting)

Anonymous Coward | about 2 years ago | (#41646951)

In Asia China's Beidou/Compass should be interesting now, and we'll see how quickly the next phase comes along.

And Japan's QZSS is easily usable by GPS receivers with the right software.

Re:Chicken::egg. (1)

anared (2599669) | about 2 years ago | (#41647593)

And Galileo will be the most accurate of them.

Re:Chicken::egg. (5, Informative)

BradleyUffner (103496) | about 2 years ago | (#41646817)

Are there any consumer gear that can receive Galileo?

I don't see how this could possibly be called a Chicken and the Egg type problem, as the satellites are are already in space to support consumer devices. They obviously didn't need consumer device support to get things started at all.

Good to hear (5, Interesting)

Sycraft-fu (314770) | about 2 years ago | (#41646557)

There has been far, far too many delays and political fuckery with this. I'm glad to hear it is finally going online.

Satellite navigation is just very important to everything these days (it is the primary nav method for all planes, ships, etc). Having everything rely on GPS, and thus on the budget the US chooses to spend keeping it working, is not a good idea.

This will make things much more reliable since, after an initial hissing match, the US and EU settled down and the systems play nice together and you'll be able to get devices that use both for better accuracy and reliability.

Re:Good to hear (4, Insightful)

Grave (8234) | about 2 years ago | (#41646629)

Oh, the budget for GPS will pretty much never be cut until the system becomes obsoleted by something newer. The US military relies on GPS. However, the more navigation systems we have, the faster and more reliable fixes can become for civilian use.

Re:Good to hear (1)

Anonymous Coward | about 2 years ago | (#41646725)

GPS is not the primary means of navigation for airlines. It sees a lot of us in General Aviation, but not for scheduled airline service.

Re:Good to hear (5, Interesting)

caseih (160668) | about 2 years ago | (#41646803)

In agriculture GPS guidance systems already have the capability of talking to Galileo when it is finished, and Glonass right now. After the military, agriculture is probably the most dependent on positioning technology these days. If GPS guidance goes down (IE our hardware has a problem), we simply cannot drive the machines. They are too wide to drive manually (my sprayer is 120 feet wide-- very difficult to drive that manually at less than 5 feet overlap even with markers) and the inputs too expensive to waste on overlaps. If GPS fails, everyone can switch to Glonass with Glonass correction signals, which should keep us going, but Galileo would offer superior accuracy and also precision. Such a switch, however, is not instantaneous. Would take weeks or months to get the firmwares updated (though the radios already are capable). And if that failed, I guess we can do terrestial positioning signals.

But it's not a matter of if GPS will fail. It's a matter of when. Maybe the US will be able to replace satellites when they die, but if not, it should be very interesting to see what happens.

Re:Good to hear (-1, Flamebait)

Jane Q. Public (1010737) | about 2 years ago | (#41646919)

" If GPS guidance goes down (IE our hardware has a problem), we simply cannot drive the machines. They are too wide to drive manually (my sprayer is 120 feet wide-- very difficult to drive that manually at less than 5 feet overlap even with markers) and the inputs too expensive to waste on overlaps."

They did it -- with the same size machines -- before GPS.

Cry me a river.

Re:Good to hear (0)

Anonymous Coward | about 2 years ago | (#41647103)

They did?! No doubt they used to drive them without GPS, but at less than 5 feet overlap? That's very hard to believe. And how did they even know they were that accurate? Yes farm machines were invented long before GPS, but GPS and other new technology make farming much more efficient, leading to higher crop yields, lower food prices, food for more people... you know all that crap that makes us a more advanced civilization.

Re:Good to hear (0, Interesting)

Anonymous Coward | about 2 years ago | (#41647119)

No they did not.
Farm machinery has grown in size and complexity over the last couple of decades. GPS is now REQUIRED for many machines.

But i know you're just arging to be a douchebag even tho you know nothing about the topic at hand.

So just foad eh?

Re:Good to hear (-1, Troll)

Jane Q. Public (1010737) | about 2 years ago | (#41647151)

"Farm machinery has grown in size and complexity over the last couple of decades."

Why? Are you saying it's because GPS was there? That's pretty stupid. It might be true, but it's pretty stupid.

"GPS is now REQUIRED for many machines."

Then get different machines. I still don't give a damn. You can put up some reflectors at the edge of your field and use a goddamned laser. There are about 100 ways to get around this "requirement".

And you can think I'm trying to be a douchebag all you like. What I'm doing is giving my honest opinion. If you don't like it, that's fine; ignore it. But I *DO* know something about it. I live in an area that is mostly rural, and mostly farms (where the terrain is not prohibitive, that is). So FOAD yourself.

Re:Good to hear (1)

R3d M3rcury (871886) | about 2 years ago | (#41647173)

They even drove 10 miles through the snow! Uphill! Both ways!

Re:Good to hear (1)

davester666 (731373) | about 2 years ago | (#41647285)

And without those sissy tires. All wood wheels RULE!

Smartphones already use both GPS and GLONASS (0)

Anonymous Coward | about 2 years ago | (#41646869)

Once Galileo and Beidou are... what happens?

Re:Good to hear (0)

Anonymous Coward | about 2 years ago | (#41647067)

it is the primary nav method for all planes

No it isn't. Its a secondary system. Terrestrial signals are still the primary source of navigation, at least in the US. Sure, plenty of private pilots use GPS like its the primary method, but the FAA doesn't allow it by law. Its simply not reliable enough to use when peoples lives are at stack.

Second, the systems already play well together, they dont' share the same spectrum, problem solved before it existed. You can already get devices with Galileo, GLONASS as well as USGPS support.

Re:Good to hear (4, Funny)

Noughmad (1044096) | about 2 years ago | (#41647473)

Its simply not reliable enough to use when peoples lives are at stack.

Just allocate people on the heap, and we're all safe?

Re:Good to hear (-1)

Anonymous Coward | about 2 years ago | (#41647215)

Then just GTFO.

cooperation between systems? (1)

bcrowell (177657) | about 2 years ago | (#41646567)

So now there's GPS, GLONASS, and Galileo. Is there going to be cooperation between the different sets of satellites, or will a given device only talk to its own set of satellites? It sucks, for example, when I'm hiking and can't get a GPS fix because I'm in a canyon with a view of only part of the sky. Ditto when all the visible satellites are near the horizon, so the vertical position's accuracy goes to hell, like a couple of weeks ago when I was at 7000' and it told me I was at 14000'. If we had a large number of satellites all in the sky at once, and could use them in any combination, it would be really cool.

Re:cooperation between systems? (1)

Anonymous Coward | about 2 years ago | (#41646593)

Basically, yes. There are receivers that use GPS and GLONASS right now, and work exactly as you hope.

Re:cooperation between systems? (3, Informative)

dakohli (1442929) | about 2 years ago | (#41646613)

Yes [novatel.com]

As we add satellites, even from different systems, the accuracy will get better. It is very cool.

Re:cooperation between systems? (2)

PhrostyMcByte (589271) | about 2 years ago | (#41646643)

Many newer smartphones built in the past 2 or so years can already use GPS and GLONASS combined. I don't see why we wouldn't get Galileo and Compass added to that mix.

...Why? (0, Redundant)

Revotron (1115029) | about 2 years ago | (#41646581)

Why is Europe spending billions to create their own GPS constellation when the US government already went through the hassle and expense? The GPS system is free and open to use by anyone with a GPS receiver. This strikes me as nothing but a political move, as if to say "We're independent and don't need America to provide anything for us". This is a completely redundant and pointless project by the EU.

Re:...Why? (0)

Luke_2010 (1515829) | about 2 years ago | (#41646609)

Galileo is much more precise than GPS. And that's just for starters.

Re:...Why? (1, Interesting)

Jane Q. Public (1010737) | about 2 years ago | (#41646947)

"Galileo is much more precise than GPS. And that's just for starters."

No, it isn't. It's just that unlike GPS, the precise part is open to the general public.

Also, I think OP is incorrect. The only reason for a 4th lock using GPS is to get the precision you would normally get with 3, if you were military. If the new system is open and precise, 4 sats should probably not have to be visible.

Re:...Why? (0)

Anonymous Coward | about 2 years ago | (#41646981)

The 4th sat is for elevation. 3 to fix you in 2D. 4 to fix you in 3D.

Re:...Why? (1, Interesting)

Jane Q. Public (1010737) | about 2 years ago | (#41647043)

"The 4th sat is for elevation. 3 to fix you in 2D. 4 to fix you in 3D."

No. That's with GPS, and that's after the fixes for precision that are necessary because the "high precision" part of U.S. GPS is restricted to military.

With an open system, it should require no more than 3 visible sats to fix your position in 3D.

Somebody tried to argue this point with me a couple of weeks ago, and it's simply false. You can get a rock-solid 2D position with only 2 observation points. 3 (and even just the first 2, if they are transmitting the appropriate data) can establish elevation.

Re:...Why? (4, Interesting)

ZigMonty (524212) | about 2 years ago | (#41647189)

You need at least one other sat to fix you in time. The receiver doesn't have an atomic clock and so needs an extra point of data for the extra unknown.

Simple logic might win an argument, but that doesn't make you correct.

Re:...Why? (-1)

Jane Q. Public (1010737) | about 2 years ago | (#41647381)

Nevertheless, I am still correct. The 4th sat is only for precision. It is not necessary for location.

Re:...Why? (0)

Anonymous Coward | about 2 years ago | (#41647445)

No, you're not correct. The 3D information that you'd get without the fourth satellite would be so inaccurate as to be meaningless. You need the fourth satellite for a 3D fix that puts you in the right city, let alone the right street. That's qualitatively different from "only for precision".

Re:...Why? (-1, Flamebait)

Jane Q. Public (1010737) | about 2 years ago | (#41647469)

"No, you're not correct. The 3D information that you'd get without the fourth satellite would be so inaccurate as to be meaningless. You need the fourth satellite for a 3D fix that puts you in the right city, let alone the right street. That's qualitatively different from 'only for precision'."

Then why do the military only require 3 satellite locks? Eh? Answer me that, you fucking genius.

Re:...Why? (1)

Anonymous Coward | about 2 years ago | (#41647609)

You can reduce the error margin of a 3 satellite 3D fix by using more accurate clocks. That's not unique to the military signal. It's just a matter of how much money you want to throw at the problem. Qualitatively, this still means you can only get meaningful 3D position data with at least 4 satellites, because the cost of a sufficiently accurate local time signal is prohibitive, especially considering that you can get a 2D fix instead or just use a fourth satellite, because they're really not that scarce.

Re:...Why? (-1, Troll)

Jane Q. Public (1010737) | about 2 years ago | (#41647573)

I am replying to you, but this is really aimed at these other dimbulbs who are arguing with me.

Listen up, folks. I don't claim to be the brightest bulb in the universe myself, but I do pretty good and I remember my recent history, which many of you seem to have (forgotten; never learned; didn't pay attention... pick your answer).

GPS has been around for a long time. But it was only pretty recently that we civilians learned about it, and it became something useful. Why? Well, that's a story.

Much of the GPS signals are encrypted, for use by the military. The high-precision part. When people saw potential for civilian use, they were somewhat dismayed, because the un-encrypted part of the signal was pretty inaccurate. Your location could only be found within a few tens of meters. Not good enough.

So a few electronics companies -- at about the same time -- came up with the idea of using a FOURTH satellite to correct the sloppy timing they got from the USUAL 3, used by the military.

And thus practical, consumer GPS was born.

But make no mistake: GPS was designed to work -- does work, still works very well -- for the military with only 3 sats visible. That is the way it was designed, that is the way it works.

So stop giving me all your theory about how it "needs" 4. You are just plain wrong.

Re:...Why? (2)

TooMuchToDo (882796) | about 2 years ago | (#41647193)

Simple geometry states you need three satellites for an accurate 2D fix, and four satellites for a 3D fix, not whether you have access to the encrypted P(Y) code.

http://gis.stackexchange.com/questions/12866/gps-positioning-why-four-satellites [stackexchange.com]
http://www.cmtinc.com/gpsbook/chap5.html [cmtinc.com]
http://www.gpsnuts.com/mygps/gps/technical/ed.htm [gpsnuts.com]

Note that the final reference I list is written by someone who is a GPS analyst and has worked for the DOD on the GPS system since 1975.

Re:...Why? (-1, Troll)

Jane Q. Public (1010737) | about 2 years ago | (#41647303)

"Simple geometry states you need three satellites for an accurate 2D fix, and four satellites for a 3D fix, not whether you have access to the encrypted P(Y) code."

Um... Duh... simple geometry doesn't apply here, because these are TRANSMITTERS THAT KNOW THEIR OWN LOCATION IN SPACE AND TIME.

Get that?

Re:...Why? (0)

Anonymous Coward | about 2 years ago | (#41647357)

So?

Re:...Why? (0)

Jane Q. Public (1010737) | about 2 years ago | (#41647373)

The real answer -- which I already gave earlier -- is that the additional lock is for error correction. Nothing more. It is NOT essential for location, including elevation.

Re:...Why? (0)

Anonymous Coward | about 2 years ago | (#41647421)

Suppose you have three known satellite positions and you can get a signal from each of them which tells you when the signal was sent. How do you calculate your 3D position? (You have the local time, but only accurate to within a +-0.1ms error margin.)

Re:...Why? (0)

Jane Q. Public (1010737) | about 2 years ago | (#41647407)

Which, by the way, your own references say very clearly.

Triangulation vs Trilateration (0)

Anonymous Coward | about 2 years ago | (#41647433)

I would have originally insisted that the GP was correct, because I believed that GPS uses triangulation [wikipedia.org] to determine location. Two intersecting lines would give a 2D position, three intersecting lines would yeild a 3D position, etc.

I clicked through your links and was confused because they have two different reasons for having 4 satellites. The first describes the geometry of four intersecting spheres, the second explains that a fourth satellite is required in order to synchronize timing for accurate distance measuring.

It appears that my assumption that GPS uses triangulation is wrong. It uses trilateration [wikipedia.org] . In triangulation, you use the angle of the lines to determine where they intersect. With trilateration, it is the length of the radius (the distance to the satellite) that is used to calculate position, but the Wikipedia example diagram only requires three spheres.

So I'm still left confused and too tired to sort it all out. Is the fourth satellite a solution to a geometric problem, or a timing/measurement/accuracy problem? If it's a timing problem, why does the fourth satellite need to be the timekeeper?

Re:...Why? (0)

Anonymous Coward | about 2 years ago | (#41647223)

The way these systems tell you where you are is that each satellite sends a time signal and is on a known orbit. You might think that by doing that, each satellite gives you one distance information. Then you could interpret it as your position being on the sphere around that satellite with the radius given by the distance. Multiple satellites would give multiple such spheres and your position would be on their intersection. The intersection of two spheres is a circle. Intersect that with the surface of the Earth and you get one position. Voila, 2D fix. Unfortunately it's not that simple. One signal alone doesn't give you enough information to calculate your distance from the known satellite position, because you don't have sufficiently exact local time information. So what your GPS receiver does is take the signal from another satellite and calculate the time difference. That's why you need three satellites for a 2D fix and four satellites for a 3D fix.

Re:...Why? (1)

maxwell demon (590494) | about 2 years ago | (#41647557)

Basically it is as follows:

The first satellite just gives a reference time. By itself, it is completely useless for positioning.
Each further satellite effectively allows you to determine one coordinate. Since you need three coordinates in order to specify a coordinate in space, you ultimately need four.

Re:...Why? (1)

Anonymous Coward | about 2 years ago | (#41646615)

because US can turns off the GPS.

Re:...Why? (4, Informative)

sidthegeek (626567) | about 2 years ago | (#41646631)

Well, the US did have selective availability [wikipedia.org] enabled for a while. Perhaps European civilians don't want to be affected by US decisions.

Re:...Why? (1)

TooMuchToDo (882796) | about 2 years ago | (#41647197)

Selective availability can be turned on by geographic region, in order to degrade the civilian signal. This allows you to only degrade the middle-east, while still maintaining precision position determination for the rest of the world. If the US wants to deny position determination, they would just jam Galileo. I supposed the EU could always send the US a sternly worded letter if that were to occur.

Re:...Why? (2, Insightful)

Anonymous Coward | about 2 years ago | (#41647415)

Yeah, except that jamming Galileo would provoke a vastly different response from the EU than the US turning some switches off on their own positioning system. You know, this isn't a computer game where the only thing that counts is what you can *technically* do.

Sternly worded letter? Fights happen in economy today, not on the battlefield. US citizens like to think they're safe just because no country is stupid and suicidal enough to drop bombs on them.

Re:...Why? (1)

JockTroll (996521) | about 2 years ago | (#41647561)

Fights that happen in economy can rapidly turn into something less palatable, especially when one of the sides has all the big sticks and no qualms at all to use them. The EU is in the middle of a darn big crisis and its "economic" power is greatly diminished. It couldn't even police its borders (the Balkans) without NATO - and with a heavy US contribution. If push comes to shove, the EU will cave in, unless they're prepared to use the French nuclear submarine "Force de Frappe" against US mainland.

Re:...Why? (3, Informative)

dakohli (1442929) | about 2 years ago | (#41646641)

Why is Europe spending billions to create their own GPS constellation when the US government already went through the hassle and expense? The GPS system is free and open to use by anyone with a GPS receiver. This strikes me as nothing but a political move, as if to say "We're independent and don't need America to provide anything for us". This is a completely redundant and pointless project by the EU.

Sigh,

It is a measure of trust. No one, trusts that the US will not screw with GPS if it would give them a military or economic advantage. Sure they say right now that they won't, but who knows what will happen in 5, 10 or 15 years in the future. And trust me, the value of an accurate navigation/timing system makes it well worth the efforts the Europeans, the Russians and the Chinese are making to field their own versions.

Why can't we all be friends?

Re:...Why? (1, Insightful)

Jane Q. Public (1010737) | about 2 years ago | (#41646969)

"Why can't we all be friends?"

Because some of those "friends" will eat your lunch.

Don't be paranoid... but don't be a fool, either.

--
Peace through superior firepower.

Re:...Why? (0)

Anonymous Coward | about 2 years ago | (#41647041)

It is a measure of trust. No one, trusts that the US will not screw with GPS if it would give them a military or economic advantage.

Except you made it even easier. The US can jam these signals or destroy the satellites in orbit without harming American interests.

Re:...Why? (3, Insightful)

maxwell demon (590494) | about 2 years ago | (#41647597)

I think destroying the satellites would be the equivalent of a declaration of war. I'm not sure the U.S. would want to declare war on its allies.

Of course should the U.S. and Europe no longer be allies at the time that happens, then if the U.S. kills the Galileo satellites, I guess Europe's answer would be to kill the GPS satellites. Again, not exactly what the U.S. wants.

Re:...Why? (1)

tsa (15680) | about 2 years ago | (#41647321)

I bet the US is already working on finding a way to scramble Galileo and other GPS satellite signals.

Re:...Why? (0)

Anonymous Coward | about 2 years ago | (#41647511)

I'll take that bet, and probably win. Because they're not working on it, they've probably finished it already.

Re:...Why? (1)

simcop2387 (703011) | about 2 years ago | (#41646711)

The US also has the ability to disable GPS for certain areas and has in the past degraded the quality of data for national security reasons ( http://www.gps.gov/systems/gps/modernization/sa/ [gps.gov] ). Though this has been changing (new satelites don't have it, though really it's just a software update), it puts pressure on other places to put up their own systems that are either compatible or at least non-interferring so that should the US ever do anything like that again, they cannot be impacted by it. It's a bit like MAD but instead of destruction, nobody can ever get degraded service (assuming enough players). This also raises the question of who should pay for it all, since with three systems now going that all work, it could let each place share only a part of the costs (eventually).

Re:...Why? (0)

Anonymous Coward | about 2 years ago | (#41646737)

You see, us Europeans know that Americans are hard working souls and as we don't pay US federal income taxes, we don't want to be US government freeloaders who have the victim mentality.

That said, if you're really that opposed to waste (and you seem like such a generous soul allowing us Europeans to use your GPS for free). I'm sure our governments can come together for a mutally beneficial agreement whereby we pay the US a nominal amount for a transfer of intellectual property as well as the ownership of the satellites. We'll then take over the running (we wouldn't want to tax your generosity any further) of the satellites. Obviously, the nominal amount would be substantially less than the cost of developing our own, because otherwise, it wouldn't be mutally beneficial.

Re:...Why? (4, Insightful)

hawguy (1600213) | about 2 years ago | (#41646961)

Why is Europe spending billions to create their own GPS constellation when the US government already went through the hassle and expense? The GPS system is free and open to use by anyone with a GPS receiver. This strikes me as nothing but a political move, as if to say "We're independent and don't need America to provide anything for us". This is a completely redundant and pointless project by the EU.

Even as an American I can see the value in having a completely separate system for satellite navigation. Even ignoring the ability of the USA to reduce the accuracy (or completely shut off) the system, the system is still a potential single point of failure subject to software problems or a rogue agent controlling the ground stations. Much better to have a completely separate redundant system with no common elements.

Re:...Why? (1)

flyingfsck (986395) | about 2 years ago | (#41647513)

There are also navigation systems that use geostationary satellites, e.g. Egnos and Inmarsat.

Competition is never redundant (0, Funny)

Anonymous Coward | about 2 years ago | (#41646967)

Competition is never redundant, and EU is trying new things with their GPS systems.

The GPS system the US built hasn't been improved for a decade, they haven't blocked spoofing of civilian signals, yet they did for military ones. EU wants to have its own system and they'll expand the features list independently of the USA. This in turn will causes the USA to improve its system. So we'll all get more accurate GPS and less prone to spoofing and interference.

Besides, the USA is run by nutcases, what if one of those nutters decides to defund GPS because God told him to??

http://bostonherald.com/news/us_politics/view/20121006congressman_calls_evolution_lie_from__pit_of_hell
Republican Paul Broun is on the Congressional science committee BTW.

Re:...Why? (1)

Yoda222 (943886) | about 2 years ago | (#41646975)

Why did the US spend billions to create their own HST when Gallileo build a telescope 400 years ago ? The gallileo telescope can be rebuild for 10$ and used by anyone with a least one eye.

Re:...Why? (0)

Sir_Sri (199544) | about 2 years ago | (#41647289)

It is political. It's a trust issue. The Europeans don't feel the US can be trusted to not just encrypt the whole damn thing for their own purposes, or fail to maintain it whatever. Relying on something you have no control over is very risky.

How do they navigate now? (0)

Anonymous Coward | about 2 years ago | (#41646583)

Article did not answer: If Europeans don't have GPS yet, how do their existing sat-navs work? And why is this new system only for Europe?

Re:How do they navigate now? (1)

Baloroth (2370816) | about 2 years ago | (#41646827)

Article did not answer: If Europeans don't have GPS yet, how do their existing sat-navs work? And why is this new system only for Europe?

The Europeans do have GPS, it's publicly available and "global" is in the name. There is also the Russian GLONASS, which is basically the same. The EU doesn't have it's own network, though, which is important for political reasons (and only political reasons). Although there are some technical improvements Galileo makes over GPS, they certainly don't justify a new system. It's also available for everyone, or at least will be, if it ever gets operational (again, global).

Re:How do they navigate now? (1)

flyingfsck (986395) | about 2 years ago | (#41647489)

and there are also systems that use geo stationary satellite data, for example Egnos.

Only three sats needed! (0)

Anonymous Coward | about 2 years ago | (#41646585)

You can use data from 3 satellites to get a fix.
You need a fourth one for an getting altitude.

a minimum of four satellites are required (4, Informative)

frovingslosh (582462) | about 2 years ago | (#41646601)

because a minimum of four satellites are required in the sky for a smartphone or vehicle to use their signals to calculate a positional fix.

Lets be more accurate here. A minimum of 4 satellites are required to be in the sky that can be observed at the same time from the same point on earth. Hopefully these satellites are relatively close together, because otherwise they might never all be visible at the same time. And if they are, since they are in low earth orbit they will pass by relatively quickly and only be briefly useable during each orbit. So, if the orbits are close this may allow a little bit of testing, but the "system" is still too satellite poor to be of any real use for navigation (at least unless you combine the signals with info from other U.S. or Russian satellites).

Re:a minimum of four satellites are required (-1)

Anonymous Coward | about 2 years ago | (#41646679)

They are in geosynchronous orbit, something about needing to know their location I think...

Re:a minimum of four satellites are required (1)

Anonymous Coward | about 2 years ago | (#41646705)

Wrong. "23,250km-high orbit" ... GEO is 35,786 km.

Re:a minimum of four satellites are required (1)

Anonymous Coward | about 2 years ago | (#41646813)

They are in geosynchronous orbit, something about needing to know their location I think...

They are almost certainly not all in geostationary orbit. Most Global Navigation Satellite System (GNSS) satellites are not in geostationary orbits. Geostationary orbits can only be above the equator (which doesn't provide great coverage for Europe) and are also very far away from the earth (which increases the signal strength required). Wikipedia seems to indicate that the Galileo orbits are medium-earth orbits about 23,000 km above earth.

That said, for GNSS in general, there's also the possibility of non-circular orbits (eg Molniya orbit) which I believe the Indian Regional Navigational Satellite System uses.

Re:a minimum of four satellites are required (2, Funny)

Anonymous Coward | about 2 years ago | (#41646907)

Wikipedia seems to indicate that the Galileo orbits are medium-earth orbits

Not to be confused with Middle Earth Orbits, which are where we place the spy satellites used to monitor Sauron.

Re:a minimum of four satellites are required (3, Funny)

c0lo (1497653) | about 2 years ago | (#41647237)

Wikipedia seems to indicate that the Galileo orbits are medium-earth orbits

Not to be confused with Middle Earth Orbits, which are where we place the spy satellites used to monitor Sauron.

I guess you mistake the for Middle Earth Orbs used for the same purposes.

The ones made by the Elves of Valinor in the Uttermost West, and marketed under the Palantir [wikipedia.org] brand, were considered the best... until it was discovered that not only they tracked the location of its users but also subtly altered the information, in a way targeted for each particular user (very much like the targeted ads today):
1. Saruman looked through the Orthanc stone, and saw what he thought was an unassailable strength in Mordor, helping to corrupt him
2. Sauron, looking the other way with voyeuristic intent thought, thought Pippin had the One Ring
3. when Denethor used the stone, it convinced him there was no hope for Minas Tirith, driving him to suicide

Needless to say, once all of the above has been exposed, their customers lost confidence, so the production of new devices was interrupted.
It took quite a long time until the brand was resurrected and today it seems to enjoy commercial viability again.
A word of caution for the would-be consumers of their services: rumours have it that the new management team can not resist co-contracting alongside trolls [wikipedia.org] if they were given an opportunity.

Re:a minimum of four satellites are required (1)

hawguy (1600213) | about 2 years ago | (#41646973)

because a minimum of four satellites are required in the sky for a smartphone or vehicle to use their signals to calculate a positional fix.

Lets be more accurate here. A minimum of 4 satellites are required to be in the sky that can be observed at the same time from the same point on earth. Hopefully these satellites are relatively close together, because otherwise they might never all be visible at the same time. And if they are, since they are in low earth orbit they will pass by relatively quickly and only be briefly useable during each orbit. So, if the orbits are close this may allow a little bit of testing, but the "system" is still too satellite poor to be of any real use for navigation (at least unless you combine the signals with info from other U.S. or Russian satellites).

If you'd quoted the previous sentence: it becomes possible to test Galileo end-to-end, it'd be clear that they meant that it is possible to test the system, no one said it's a usable navigation system.

Multibillion pissing contest (-1, Troll)

onyxruby (118189) | about 2 years ago | (#41646655)

Galileo is nothing but a multi-billion dollar pissing contest with the US to say "look at me, I can make my own GPS". When the continent is neck deep in an economic crisis that is miring millions of people and putting nation states on the verge of collapse, their priorities are seriously misplaced.

Seriously, there is no real benefit to this other than vanity and snubbing their noses at the United States. This has seriously got to be one of the most foolish economic decisions they have made in decades. Might as well spend billions of dollars making your own version of the Internet for the same reasons and results.

Re:Multibillion pissing contest (3, Insightful)

timeOday (582209) | about 2 years ago | (#41646685)

That must be exactly what Russians think about us not wanting to use their fine space launch services indefinitely.

Re:Multibillion pissing contest (0)

Anonymous Coward | about 2 years ago | (#41646837)

RU is a very different civilization, with very different geopolitical interests.

No countries in the top quarter of the Economic Freedom Index [heritage.org] will ever have a serious conflict amongst themselves, ever.

EU (especially its best countries, like UK, NL, DE, etc) and US are largely on the same page when it comes to economic freedom and free trade, while RU remains an unstable wildcard (even more-so than CN). Some EU countries (FR, IT, etc) are major disappointments, but they're too weak to do anything by themselves. US'ians may justifiably call FR'ies "socialists", but it is a relative judgement - there's still a vast difference between them and RU.

So EU depending on US is a smart choice, but US (or anyone) depending on RU isn't.

--libman

Re:Multibillion pissing contes (1, Insightful)

Serious Callers Only (1022605) | about 2 years ago | (#41647459)

The EU sees the US as far less trustworthy than you do, and expects to come into conflict with it again - war is unlikely but economic and policitical spats are quite common between the two. In addition to that galilleo lets them have greater accuracy than the US will allow with GPS, and ensures that they don't have a strategic dependency on the US in space.

Strange how myopic and solipsistic the view from the US is sometimes.

Re:Multibillion pissing contest (1, Insightful)

toutankh (1544253) | about 2 years ago | (#41647579)

Seeing how the USA are the biggest bully on the planet, it is a smart choice for no country to depend on them, even for the EU, itself made of big bullies.
The USA have already misbehaved [historycommons.org] with their "friends" and there is no reason to believe that they will not do it again. Therefore seeking independence from them is the sane thing to do.

Re:Multibillion pissing contest (0)

Anonymous Coward | about 2 years ago | (#41646753)

You're spot-on.

This is nothing but a propaganda project for Europeans to escape reality. The idea that, after decades of parasitism, EU would become militarily independent from the USA is ridiculous! They can hardly afford this >5-gigaEuro toy, which they're building at a time of a debt crisis, and they'd need 100s of times more to be independent!

So they're getting no benefits, just costs (with debt interest), and this also goes a long way squash the potential of private satellite navigation networks from taking off...

--libman

Re:Multibillion pissing contest (4, Insightful)

Space cowboy (13680) | about 2 years ago | (#41646809)

When your international reputation is at an all-time low you should expect things like this... Galileo was started way before the US popularity took a nose dive, but the last decade or so are only going to make projects like this *more* likely. To the civilised world, the US is not one of the good guys any more, they're not in "bad guy" territory yet, but they're sure headed there fast.

Basically the world no longer trusts the USA. Simple as that.

Simon.

Re:Multibillion pissing contest (-1, Flamebait)

tbird81 (946205) | about 2 years ago | (#41646913)

Yes we do. I trust the USA, much more than the unelected corrupt EU politicians.

Re:Multibillion pissing contest (-1, Flamebait)

DNS-and-BIND (461968) | about 2 years ago | (#41646999)

Those evil Americans! Making their insidious GPS service available to the world for free! Bringing billions of dollars of cost savings to foreigners all over the world in the form of reduced fuel costs, increased agricultural efficiency, and time saved. They had it all planned from the beginning, those bastards!

Look, if you're going to mindlessly bash the Americans, do it right. Say something like "GPS was conceived by the perverted violent minds of the military, while our Galileo is a system of peace. Thus proving, once again, the innate superiority of Europeans over the Americans we have looked down upon ever since we kicked their sorry asses out of our own countries for having the wrong religion."

Re:Multibillion pissing contest (4, Interesting)

Space cowboy (13680) | about 2 years ago | (#41647123)

Jesus, tunnel vision much ?

Look it's nothing to do with GPS vs Galileo. It's to do with the USA, a nuclear power, declaring war left, right and center, & invading other countries basically because it can. No-one likes that; international reputation suffers, trust is lost, and consequences ensue. There's no point in getting pissy about it, you brought it on yourselves.

I don't think Europeans are innately superior. I think people are just people, wherever you are. I'm married to an American woman, whom I love dearly. I do think the USA is fucked though, the society is (IMHO) past the tipping point and heading down, and I can't see myself staying around much longer, as I've said before on this site. At some point, the money just ain't worth it.

Simon

Re:Multibillion pissing contest (0)

Anonymous Coward | about 2 years ago | (#41647229)

Nobody is stopping you. Please leave. Seriously.

Re:Multibillion pissing contest (1)

Anonymous Coward | about 2 years ago | (#41647095)

"Nose dive"? That is bullshit from the socialist fantasy bubble! Now here's a summary of objective benchmarks by which a country's reputation can be judged...

USA is #1 in overall National Brand [wikipedia.org] ranking, and #1 in international tourism receipts [wikipedia.org] (in spite of really shooting itself in the foot with all the post-9/11 security theater). USA gets more foreign investment [cia.gov] than any other country - more than twice as much as the runnerup. It has the world's most respected universities [wikipedia.org] , and some of the most admired [cnn.com] and best managed [wikipedia.org] companies. USA's credit rating [wikipedia.org] went down a bit under Obama, but only a handful of countries rank higher. It ranks higher among preferred immigration destinations [athousandnations.com] than most of Europe (sadly too many survey respondents thought France was a romantic destination, even though most people who visit it are disappointed) (and justly behind small Economic Freedom champs like SG and NZ).

USA's reputation was at an "all-time low" shortly after the Revolution, when it was seen as a pirate nation of rootless migrants and uncivilized wilderness. USA's reputation gradually went up and up during the 19th century, leapt upward as it became a superpower and a powerful anti-colonial influence after WW1, and went further up in the civilized world after WW2 and during the Cold War.

--libman

Re:Multibillion pissing contest (1, Interesting)

Space cowboy (13680) | about 2 years ago | (#41647149)

Right, I'm talking about a cop executing a handcuffed helpless suspect [youtube.com] [warning. Graphic.] and the lack of respect for the law that "peace officers" show; about the TSA, just the very fact of its existence; about the demagoguery that passes for news and its knock-on effects on society; about the constant military action taken to divert attention from problems; about the massive debt and crippled economy; about the shameful lack of a decent for-all healthcare system; about the proliferation of lethal weapons that for some reason is enshrined in the country's constitution!, and the horrendous murder statistics that it produces; about the general sense inherent in US society that "everything's ok as long as *I'm* ok, screw you guys" ... I could go on... and on.... and on...

And your point is that the "national brand" is good. Well whoopy-do. That's all right then. Phew! Glad *that*'s sorted out! .... Fuck me, it's worse than I thought :(

Simon.

Re:Multibillion pissing contest (3, Insightful)

bigt_littleodd (594513) | about 2 years ago | (#41646987)

Your comment is short-sighted.

GPS, whether American, Russian, or EU, is first and foremost, a military asset for their respective owners.

The US military can elect to disable or cripple civilian GPS service to all devices other than their own when they deem it necessary to prevent its use by hostile forces. Presumably, GLONASS and the EU systems have the same capability.

History repeatedly shows that international political alliances vary over time. Just because we currently are at relative peace with the EU and Russia, that does not mean it will always be so in the decades to come. I'm not saying we will be in a hostile situation with either in the future, but it's not out of the realm of possibility, either.

The EU is building their own system not because they want to win a "pissing match" with the US or Russia. It would be foolish of them strategically to depend on a GPS that is under someone else's control.

Re:Multibillion pissing contest (0)

Anonymous Coward | about 2 years ago | (#41647233)

USA has no interest in hurting the global economy - it spends hundreds of billions a year to protect it! It won't turn off GPS just to fuck with its allies in Europe - that is insane! (Inside joke: Uncle Sam is no Ian Fraudman...)

The odds of USA ever turning off GPS due to a military threat are theoretical, and nearly non-existent in practice. I guess that scenario imagines a missile fired by al Qaeda / Iran / North Korea / etc trying to use USA's own satellites to guide it... But, why?! There are lots and lots of options for building a device to detect position [wikipedia.org] - other countries' or private satellites, phase difference from terrestrial cell towers, Earth magnetic field, on-board optical recognition of the terrain, simple internal inertial sensing, target beacons, etc, etc, etc.

Cut-off switches are pointless. We need to transition to a private satellite infrastructure, and both USA and EU need to stop buying so many toys on credit and get their respective fiscal houses in order!

--libman

Triangulating position (0)

Anonymous Coward | about 2 years ago | (#41646699)

I love how position is often triangulated by connecting points to form something other than a triangle.

Re:Triangulating position (0)

Anonymous Coward | about 2 years ago | (#41646751)

Triangulation is downright childs play compared to using satellites to figure out where you are. You have to take into account general relativity, atmospheric distortion and variability of gravity to get useful coordinates, and even more processing and dgps stuffs can get you down to the cm/mm range.

Re:Triangulating position (1)

hawguy (1600213) | about 2 years ago | (#41647017)

I love how position is often triangulated by connecting points to form something other than a triangle.

I thought the "triangulation" name came from forming a triangle between yourself and each remote point (and depending on the accuracy you desire, there could be many remote points)

It's not that you're drawing one big triangle on a map, you're using many (or at least several) triangles to known points.

Do you really need 4-5? (1)

mattr (78516) | about 2 years ago | (#41646767)

I wonder, since you can pretty much figure out what city you are in through ordinary radio and wifi beacons, not to mention the help you could get from having a clock and a sun locator, couldn't you really use GPS on the road with just two or three satellites?

Re:Do you really need 4-5? (1)

BradleyUffner (103496) | about 2 years ago | (#41646847)

I wonder, since you can pretty much figure out what city you are in through ordinary radio and wifi beacons, not to mention the help you could get from having a clock and a sun locator, couldn't you really use GPS on the road with just two or three satellites?

Not with any kind of accuracy. the math involved in GPS calculations requires specific known timings between highly synchronized systems. Those other sources may help you get a location fix more quickly, but they aren't going to help with accuracy.

Though I am fairly sure you can get a positional fix with just 3 satellites, not 4. The 4th is required if you want altitude along with it.

Re:Do you really need 4-5? (1)

Anonymous Coward | about 2 years ago | (#41647063)

No. 3 distances are sufficient for a 3D positional fix including height. The 4th satellite is required is to sync the atomic clocks to determine the correct distance from receiver to the satellites.

Re:Do you really need 4-5? (0)

Anonymous Coward | about 2 years ago | (#41647099)

No, 2 sats give you a massive sphere of possible locations. It would be able to tell you what hemisphere you are in, maybe. 3 narrow it down to a smaller region, but still not a point in 3d space. 4 gets you to a single point 'in a perfect scenario' which isn't technically possible, so you get a fair amount of error. You start getting a good accurate position when you float about 6 overhead at good separation from each other, if several of them are to close together or near the horizon you start going to shit again.

If you want 3 meter resolution without military grade equipment you're going to want 10 or more to deal with all the various environmental factors that introduce error into the system. Its fairly difficult for a 12 channel receiver to stay accurate with all channels connected without ground based augmentations ( WAAS)

Re:Do you really need 4-5? (2)

feedayeen (1322473) | about 2 years ago | (#41647137)

All the equipment you listed is either more expensive, less precise, or not global; and triangulation in 3d space does not really work that way. Using just 2 satellites, you would get a circular area of possible positions, of which 2 would intercept the surface of the Earth and most likely the other would be far from Europe, but you lose altitude measurement and consumer products using the technology will not be reliable outside of Europe. An argument can be made that 3 is sufficient and most GPS devices would be smart enough to ignore the second point ~50K miles from the Earth.

No GPS??? (0)

Anonymous Coward | about 2 years ago | (#41646933)

Europe has been without GPS this whole time?! Or am I reading this wrong?

Re:No GPS??? (1)

rbprbp (2731083) | about 2 years ago | (#41646965)

Hint: the G in GPS means global for a reason.

living in US, glad there's alternatives (-1)

Anonymous Coward | about 2 years ago | (#41646989)

To give the US power like that is ridiculous. At any given time the US could turn off GPS systems and no one in the world would have access to them. That's a scary though considering the US's militaristic past that is borderline (or beyond) grotesque

Survey quality GNSS systems (1)

goatbar (661399) | about 2 years ago | (#41647191)

Apparently, there are units available that will track 120 simultaneous channels across all the available systems (this comes from Dave Wells). Not having a unit in my possession (and never having messed with Rinex before), I'll have to take his word for it.
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