GPS problem

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My N1 is very difficult to fix GPS.
When indoor, I lost all stas, and when outdoor, with out cloud, it take about 3-4 min for fix GPS with 6-8 stas.
I try some solutions in here, but no lucky.

my N1 rom: cyanogen nightly build (last)
radio: 5.08....

Plz help me

Indoor fix will always be difficult to impossible. Nothing out of ordinary.
For quick outdoor fix - do you have data connectivity? Or you're not using 3G data? If not - that's the reason for a long fix time.

If you do have cellular data, try going into your APN settings and changing your primary one so that the APN type says:
default,supl

This greatly improved my lock time.

Sent from my Nexus One using XDA App

Cyanogen 6 definitely has a GPS issue: http://code.google.com/p/cyanogenmod...detail?id=2090

While AGPS settings improve the performance, something is still wrong. I remember stock Froyo to be a 5-20x times faster at getting a GPS lock (I've had cases with a clear blue sky where it's taken 120 seconds to get a GPS fix, before it was a max of maybe 10 seconds).

Also I notice that with GPS Status, I see 1, 2, then 3, 4 satellites show up, then they all disappear... and it starts again, until it gets around 7-8 satellites and gets a lock with 32m accuracy and then the precision slowly increases...

I wish someone could tell me 1) what change Cyanogen has implemented that causes this behavior 2) how to revert back to the old GPS code.

Strange. Your experience doesn't match mine. CM6 here on an AWS Nexus One, with the newer radio. I can get a lock in seconds on GPS Status.

Sent from my Nexus One using XDA App

ever since my switch to cyanogen i have had same problem

Cmstlist, turn off your data (3G and wifi) and try getting a lock with GPS Status so you can see the progress. I'm running the Rogers/AT&T version, and this bug drives me crazy. I'm running the 9/20/2010 nightly, but even RC3 had this bug.

Well if you remove access to aGPS, of course you'll take longer to get a lock.

My guess: stock N1 gets a faster lock because it has a supplementary cache of offline GPS info supplied by gpsonextra. The urls for gpsonextra appear in /etc/gps.conf in CM6 but I'm betting it doesn't function properly on an AOSP firmware. Can anyone prove my instinct right or wrong?

Sent from my Nexus One using XDA App

I've checked on Enomther's build I'm running, which is also AOSP ROM. The most significant correlation of GPS lock time I've noticed was only with data connectivity rates. I've used GPS Status, and it took ~5-10 seconds to lock both in the open near my house and on the moving train at 150km/h in a significantly changed location, with the only thing being common - there was good 3G reception in both areas. Both times it locked in 2 "batches", 3 satellites being locked in the 1st one, and another 5-6 in the 2nd one. The first "batch" is probably strong satellite signals that were locked after Almanach download almost immediately, and the other "batch" might have been post- Ephemeris download. Either that or it has gpsonextra functional - but in any case, the lock is super-fast when the data rates are good.

On the other hand, the data registered on Traffic Info is only 40k download and 20k upload - even on GPRS it won't take long. But the base station needs to support aGPS - that's also something to consider.