[marsokod]

The time to first fix is mainly impacted by whether the receiver knows which satellites to listen to. This requires two things: having the ephemeris for the constellation (either 10min of listening to GPS signal, or getting that through AGPS), and it's approximate own position/time (done through cell antenna locations, and NTP) to know which satellites should be visible.

Once this is available, the receiver can then focus on the signals that are expected and will then be able to provide a 3D fix as soon as it receives something from 4 satellites, which would be in a few seconds.