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"It's all short range communication, so application is limited."

Really? How "short" is the range of GPS these days? Looks like about 12,551.7 miles.

Galactically, that's probably "short", but there is nothing about this that is "short range" at all. GPS capability + what essentially amounts to a huge, roadway-phased mesh network, and you're talking about miles to dozens of miles of coverage between "endpoints".

GPS is not in GEO. GPS is in a Middle Orbit (MEO): about 20200km.

http://www.kowoma.de/en/gps/orbits.htm

This is incorrect.

The GPS constellation is arranged so this should be impossible unless:

• Satellites were broken
• The device was junk
• or it was being used incorrectly (for instance, without line of sight to the sky)

Although none of the satellites are in a direct polar orbit (this avoids occasional "bunching" of satellites, a problem encountered by a forerunner to GPS called "Transit".), the constellation is divided into six orbital planes at varying inclinations. There is nowhere on the surface of the Earth where fewer than four satellites should be visible at any one time.

It is true that the lack of a direct polar plane means that in polar regions the satellites will sit lower on the horizon than in regions that are closer to the equator (They'll never be directly overhead in Alaska). But if the device is capable, and it's being used properly, you WILL be able to use it in Alaska or anywhere.

Read up in it if you're skeptical:
http://home.earthlink.net/~fjolles/gps.htm
http://www.kowoma.de/en/gps/orbits.htm
http://www.colorado.edu/geography/gcraft/notes/gps/gps_f.html

You can see satellites almost any clear night ANYWHERE on Earth.

GPS satellites are low and cover every point on Earth.
If you look towards the equator, then up, there are hundreds of geostationary satellites for TV, communications and other things about 22,000 miles up. As a reference, the diameter of the Earth is about 6500 miles (I didn't look it up).

The Space Shuttle orbits around 140-180 miles up so it is barely out of atmosphere - some would say it isn't out.

http://www.kowoma.de/en/gps/orbits.htm may be helpful. There's a bunch of stuff to see. With binoculars, you can see a ton of stuff.

See Wikipedia (http://en.wikipedia.org/wiki/Speedometer_Error#Error) for info about speedometer error. Alignment has almost nothing to do with speedometer accuracy.

GPS inaccuracies occur for any number of reasons (see http://www.kowoma.de/en/gps/errors.htm for details) and GPS speed measurements are widely known for being inaccurate over both short distances and short periods of time. My GPS is often ridiculously wrong--once it had me going 200 MPH, significantly faster then the top speed of my bike :-)

No. The "control segment" of the GPS system is built to interface redundantly with all of the satellites in orbit - this includes sites on every continent except Africa and Antarctica.

> I'd be nice if we could use something different to distingish between "some" GPS and the "American" GPS.

There is: the "American GPS" is named NAVSTAR according to this site