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>2.
>>Does GPS connection cost money to be uplinked, similiar to phones?
No. GPS signals (more specifically GNSS, which includes US's GPS and Russia's GLONASS systems, among others) are constantly transmitted from orbiting satellites. GPS-L1 signals are "free" - don't need anything special to receive and decode a position from that. This is what you'll find in any GPS receiver you'll be able to afford.
Military M-signals are keyed, but provide significantly more accurate positioning (sub-centimeter). Unless you're lucky, you won't be getting your hands on that.
There's three pieces of information your receiver needs to calculate a position in space.
>Almanac
Is an "index" of all the satellites in orbit, and approximately where they are.
>Ephemeris
Details of the specific satellite's orbit.
>Time
Each bird carries a Cs-standard "atomic" clock. Extremely precise. Knowing where the satellites are, each satellite's orbit, and the difference in arrival times between each satellite's singal, your receiver can calculate its position.
Since there's numerous satellites all carrying precise time references, and that time reference is identical globally, GPS is a real easy way to synchronize systems across huge geographic areas.
>pic related
