Do cellular phones only transmit to the nearest tower, and then at point they go down into the underground (buried) land line infrastructure... and make the entire journey via the landlines until they reach the desired other party? For example, if you are in New York and use your cell phone to call someone's cell phone in Chicago -- does the signal go from tower to landline and back to tower... or does it at some point make part of (or most of) the journey via satellite? And is that contingent upon the physical distance between the two calling parties?
Depending on load and location, the fiber optic cable might be some combination of fiber optic cable, copper wire, coaxial cable, and/or microwave radio.
Satellite isn't used for voice (except satellite phones) because of the delays.
The cell phones transmit the signal to the nearest tower, and then at that point they go to the cellular phone system network infrastructure. Through that infrastructure the call goes to the cellular system central office, where it goes to whereever it needs to go (other cellular phone through same insfrastructure, to normal landline infrastructure, data to Internet etc..). The cellular phone system network infrastruture that connects the powers together and to cellular phone system central office is typically a mixture of copper lines, fiber optic lines, wireless microwave links etc..
I don't think that cellular phone calls would go though satellite normally.
The call normally would go most of the route though some infrastrure in land. Most typically most of the distance the call would go in fiber optic link...
More than the distance the variations would be depending if the different call parties are both using same operator or different operators. If two callers are in the same city and use same operator, the call woul dbe routed to the operator's central office equipment only. If the both users use different operator, the call would go to operator A central office, then to operator's interconnection point (could be in another city) and from there to operator B central office and to operato B tower...
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Tomi Engdahl (http://www.iki.fi/then/)
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