Likely, after the first calibration you could keep moving around and updating your location, so as long as the system doesn't go down you always know your (relative) position as you travel through the galaxy.
Regular GPS does this, too. It takes about 12 minutes to download the list of currently active satellites and their attributes. The data is part of the signal from the satellites.
Most GPS units do this in the background. But if you leave it unpowered for too long, it will need to update itself before it begins to work properly. The GPS in my dad's car used to have a flaky ROM, and it would show the car flying across the wilderness at over 400mph while it was updating.
Most GPS units do this in the background. But if you leave it unpowered for too long, it will need to update itself before it begins to work properly. The GPS in my dad's car used to have a flaky ROM, and it would show the car flying across the wilderness at over 400mph while it was updating.