[alex]

I agree with dog. The speed of electromagnetic radiation in vacuum is abour 300000km (299 792 458 m/s to be exactly).

And I also wonder about those stratellites. There are thousands of satellites (or 'stratellites'), so at least about 10000 people involved in building those stratellites, developing the techniques and electronics, developing rockets, handling down/uplink for communication etc must know the 'truth'. Is that estimate about correct?

[jroa]

don't have latency consistent with an orbital device thousands of kilometers away.

The speed of electromagnetic radiation is 300000 km per second. There is no latency.

Stratellites, or satellites within the atmosphere, function much in the same way satellites do in RET.

What are these stratellites made out of? How high are they? And what is their velocity?

Semiconductors do not switch states at the speed of like, therefore, latency. 

[Dog]

Semiconductors do not switch states at the speed of like, therefore, latency. 

You know what I meant. Not enough latency to justify Irushwithscvs's claim.

GPS satellites orbit in MEO at about 20,200 km. A round trip for electromagnetic radiation moving at about 300,000 km/s would take about 1/10 of a second.

[dave]

GPS operates by ground based towers.

[sakura]

GPS operates by ground based towers.

If the gps reciever can calculate its position with the signal of multiple transmitters,
this also means that multiple recievers can triangulate the position of one transmitter.

If this is true and GPS is operated by ground based towers, anyone could prove this,
yet no one ever did.

[Orbisect-64]

When I lived in Vermont it was, and still is common knowledge that GPS is very unreliable throughout the state.

And yet it's possible to get cell phone coverage in many areas.

If GPS relied on satellites, then GPS would work wherever you can pick up a cell phone signal. But that's just not the way it works.

GPS relies on towers, and if there aren't enough towers where you live (as there aren't many overall in Vermont), it does't matter how many THOUSANDS of satellites they claim to have in space, you're not going to get a signal.

If GPS really relied on satellites, there would always be a satellite above you no matter where you are, and it would be relayed to your phone.

GPS relies on triangulation, and that's all.


http://alternativephysics.org/book/GPSmythology.htm



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[markjo]

If GPS relied on satellites, then GPS would work wherever you can pick up a cell phone signal. But that's just not the way it works.

That's right, because GPS works in areas where you can't get cell phone signals.  Perhaps you're just to young to remember a time when cell phones didn't have GPS location services.

GPS relies on towers, and if there aren't enough towers where you live (as there aren't many overall in Vermont), it does't matter how many THOUSANDS of satellites they claim to have in space, you're not going to get a signal.

Actually, GPS claims to have 30 operational satellites currently operational.

If GPS really relied on satellites, there would always be a satellite above you no matter where you are, and it would be relayed to your phone.

I think that you're confusing satellite phones and cell phones, neither of which rely GPS satellites for making phone calls.

GPS relies on triangulation, and that's all.

Technically, GPS uses multilateration which is based on signal timing, not measured angles.