QuickGPSfix question

[hasiel]

When I plug in my TT, I have it set to auto. download the QuickGPSfix update. I am in North America.

Are there QuickGPSfix updates for Europe... or does the one I auto. download download work for the whole world?

If not how do I access for W. Europe, as I am going there very soon.
Thanks in advance

 

[dhn]

I believe each file contains data for all gps satellites. The satellites are not country specific.

 

[DustPuppy]

As far as i have understood, the QuickFix is just a table of where all the 24 satelites will be the following next 7 days.
It is used to quickly get a calculated fix on suitable sats, instead of receiving data fropm all it can "hear" and then calculate the most usable ones.
So instead of rummaging through the data streams, triangulate position, recalculate with new satelites,
it just looks in the QuickFix table to see: I have sat's 3,5,7,8 and 12 in good positions, lets use those streams first to obtain a true fix, and then use what ever data thats coming in.

So the file is supposed to be "world wide". Same file everywhere...

(Usual disclaimer of gotten the whole thing totally wrong of course...)

 

[thogard]

The data in the QuickGPSfix is called ephemeris so I'm guessing its just the data that the GPS chip normally downloads once its sees the sats. GPS sats transmit a rough position for all the other sats (called almanac) and exact timing and positioning data for its self (called ephemeris). I expect the data is just the predicted locations for the next week with a time code that makes sure it gets replaced once the receiver tunes into each sat.

For the NavStar sats it will be world wide. If they pull the data from only one ground station then they may only see one of the augmentation clusters so that may be just one of WAAS (US), EGNOS (Europe), or MSAS (Japan) but that won't mater much since those sats only transmit slight corrections for the main NavStar sats.