GPS is not adequate.

You can't tell which lane your in, it's not accurate enough.

You can barely tell whether your on the left 3 lanes or right 3 lanes of a motorway, again the accuracy problem, you usually determine it from the direction (i.e. if the left 3 lanes are heading south and the car is heading south, they are probably on the left 3 lanes).

Are you in the wrong lane facing oncoming traffic? Your Sat Nav doesn't know. If a country lane runs parallel to a motorway it guesses you're probably on the motorway based on how close the signal says you are.

You can't tell direction, since direction is calculated as the differential movement over time. Without accurate position, you need a big interval to even guess at direction.

If you knew location accurately you could determine the edges of the road for example to stop them going into a ditch at night.

You can't for example have 2 GPS receivers and determine direction with any accuracy, again the problem is the poor performance of the public GPS signal. So forget sticking a GPS on the head and tail of a boat as an accurate compass. Forget auto landing of planes using GPS too, it's just not accurate enough without the landing beam to assists it.

Sure the USA provides GPS for free, but only enough to make it uneconomic to make anything better. The higher clock rate is kept back for military use, the newer satellites have new feature, but the public GPS signal is still the old ones.

We can stick to GPS but then USA dictates to us the speed at which we improve our systems. Which is not a good thing.

Why not make the higher clock rate, frequency spread, and whatever other features you want a charged-for feature, so that all the new companies that can spring up making (for example),

accurate boat compasses using GPS,

head up displays of the road edges using GPS,

super accurate surveying using GPS,

weather wind direction meters based on GPS,.....

i.e. all the products that don't currently exist because the GPS signal is so crap and all the companies that don't yet exist making those products that don't exist, would pay for these extra features. It's the chicken and egg problem, those companies and product don't exist because the signal doesn't exist to permit it!

Before GPS existed there were no SatNav companies the US could ask for the money because they didn't exist until GPS existed. If they tried the same trick, demanding money from companies that didn't exist yet to use a feature they wanted to build, who would pay?

I'd like, for example, the GPS signal to carry a set of localized corrections to known points of reference to correct for atmospherics without the complex calculations (i.e. to carry a set of local differential GPS correction figures available on the satellite signal so it can be used for navigation systems).

I usually find that looking out the windscreen is enough to tell me which side of the road I'm on. Given several billion to spend, I can think of better ways of spending it.

If you really must spend it on a GPS system that the Americans can't switch off, for gawd's sake talk to the Americans so that you can use the existing protocol and frequencies. I'm sure they'd be quite happy to let you pay for part of the required constellation.

So, is this really just a big hidden sub for Ariane to try and make it more competitive with other sat launchers? The French connection makes me say "Oui!"

"I usually find that looking out the windscreen is enough to tell me which side of the road I'm on."

Funny, my satnav says 'keep left' but it actually means keep in the middle two lanes, not the right lane. It doesn't know if I'm already left enough, and neither do I which is why I'm using a sat nav!

And if you are a person driving down a windy road, can you see around corners to know what bend lies beyond? I found sat nav very useful a week ago driving down an unlit windy road at night, but sometimes it just didn't cut it. It isn't good enough to see the ditch for example, and the location of bends were hit and miss. Enough to know a right hander was coming up, but not enough to accurately place it. Also no where near accurate enough to drive a head up display showing the edges of the road ahead.

Why display the head up display just at night? I'd like it to project the road edges during the day too, to make my driving smoother.

Also why do you suppose it will be a person? What if you were an automated street sweeper? is full vision simpler to implement than a sat nav trail and collision avoidance algo?

Or perhaps a safety system on a boat. You can't even tell which side of the river the boat is on GPS is so vague. Direction is not accurately known either.

Dude, you probably shouldn't be driving at all if you need that kind of help.

Problem: Can't see the ditch

Solutions: turn on headlights; slow down; check into old age home

The suggestion that GPS be used to annotate road edges on a HUD further

suggests crazy-oldism.

"Solutions: turn on headlights; slow down;"

55mph should be fast enough for anyone. :)

W. Gates.

The real problem is that the Americans have played a blinder, politically, for the last twenty-odd years. Firstly, they demand frequency & signal-design co-ordination for interworking. Disagree, and they will ensure that your system won't work. They require the "selective availability" for military purposes - so if you design something that is too accurate, they will refuse to let you deploy it, on grounds of National Security.

Fine. Now they've got you to deploy something which is negligibly better than theirs. For interworking, they can now spend the next 20 years, blowing hot & cold with the technical specs, so you can never QUITE get to the point of deploying.

Then they will always undercut your paid-for service. Galileo COULD deploy with paid-for accuracy, for a cost of billions. As soon as it's up there, the U.S. flip the accuracy-switch, make their system temporarily more accurate, and Galileo uncompetitive. Goes out of business, accuracy-switch is flipped back, go to square 1.

Tough S. You left out the part about the enormous value collected by individuals and corporations all over the world, subsidized (sorry, that should read "paid for") by the US.

Who exactly is the "you" that they will refuse to let deploy? And what exactly is the mechanism by which this refusal happens?