Quote:
Originally Posted by RONMAC
You would have to update QGPS everytime you start in a new location. I've noticed that if I check the GPS in the same location everytime, I get a pretty quick lock. If I try to lock in a different location in the city, it will take me a while to get a lock sometimes it will be 2 minutes before I get a good lock.
That being said, would it be tru that you would have to update QGPS whenever you start the GPS radio in a new location?
To me, that is aGPS done manually, whereas true aGPS would have all this done automatically when the GPS radio is accessed by any of the software we are using.
6 to one, half dozen to the other i guess but I can see both sides.
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As long as you have downloaded within the last 5-7 days, you don't have to do anything on QGPS just because you moved locations. The almanac that QGPS download covers all the sats for about a week. I tested this today after flying from coast to coast. My last QGPS download was when I ActiveSynced before leaving my office and getting on the plane. I had a lock within 30 seconds the first time, and within 8 seconds a few hours later.
Note - if directed to cold start, the chip should clear saved ephemeris data then check if it has the almanac (which it will). With QGPS, cold start and warm start should yield similar, if not identical results since QGPS means the chip never really cold starts (i.e. no almanac). Note - hot start means saved ephemeris data should also be correct - only true if your last lock was < 3-4 hours ago and you haven't moved position. If you tell it to hot start and it doesn't find the sats it expected, it should fall back to warm start and consult the downloaded almanac. Most GPS applications don't tell the chip a mode, so I assume it defaults to hot start and falls-back as needed.