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My Touch Pro ran TomTom flawlessly until a couple of months ago when I got a problem with the GPS device (not the signal) being lost every few seconds. It would reappear again for about 5 secs then off again. Despite soft resets etc, I suspected it might be the SD card at first as I tried many restart combinations with the card in/out etc and as it seemed to help on one occasion I put it down to that. But it did happen on a regular basis.
I now have the X1 with its superb GPS implementation, I was very impressed for a few days... until you guessed it, this problem started happening again!
Luckily I remembered the only setting I had done prior to this occuring was to use the Advanced Config application, where I enabled the AGPS feature. So... I went back in and disabled it and the problem disappeared immediately. I used Advanced Config on the Touch too, so that must have been the problem for sure.
I notice that AGPS is disabled by default. Why HTC did this must mean there is a problem with this feature.
So be advised, not to use the AGPS unless anyone knows good reason to and has a fix for the problem I mentioned.
I ran into the same problem. Turned on agps in advance config, used tomtom 7 and keep getting drop signal. It would pick up the sat signal for a few second and lose it, what interesting though when I use google map it would track me fine, no lost of signal. I can see my "dot" on google map moving along. When I drive, haven't tried it with other nav software to see if this was an issue. I still wonder why they have agps turned off though as default.
i think even if its set to "disabled", its enabled. a-gps must be hard coded in the hardware itself!
ps: i have the same problems when its "enabled".
I think it's the AGPS file that might have corrupted. You can solve this by re-download AGPS file and everything will be fine.
It happened to me once or twice, but it's not a reocurring problem so I did not bother much.
which agps file?
Guess you talk about an A-GPS setting in Tom Tom?
I cannot follow your conversation. With Mobile Navigator, which has no switch to enable or disable A-GPS it works pretty fine.
Sat-fix within seconds - thanks to the provided A-GPS function of the X1, which I don't think can be disabled on teh X1, until you don't update the information frequently with the Quick-GPS application.
Maybe Tom Tom can't interpret the A-GPS information?
How long does a Sat-Fix in Tom Tom take, when you disable A-GPS (in Tom Tom)?
Eric
we are talking about a tool called "advanced config tool". there is an option of enabling and disabling a-gps. "disabled" works best for most users...
you can have a 3d fix in seconds also with no a-gps.
Eric X1 said:
I cannot follow your conversation. With Mobile Navigator, which has no switch to enable or disable A-GPS it works pretty fine.
Sat-fix within seconds - thanks to the provided A-GPS function of the X1, which I don't think can be disabled on teh X1, until you don't update the information frequently with the Quick-GPS application.
Maybe Tom Tom can't interpret the A-GPS information?
How long does a Sat-Fix in Tom Tom take, when you disable A-GPS (in Tom Tom)?
Eric
Click to expand...
Click to collapse
It's incredibly quick (even indoors) to fix a position without AGPS. I admit I haven't knowingly had any noticable problems outside of TomTom but this is something I use a lot. It copes admirably inside, in built-up or shaded areas. No real need for AGPS then! I did try updating my QuickGPS file by the way, to no avail. Disabling was the only fix!
The FIX IS TOO FAST!!!
But I don't have this problem.......
DocMAX said:
we are talking about a tool called "advanced config tool". there is an option of enabling and disabling a-gps. "disabled" works best for most users...
you can have a 3d fix in seconds also with no a-gps.
Click to expand...
Click to collapse
My X1i doesnt have an "adavanced configuration tool" application. Is this a 3rd party addon that you have installed, or is my device just configured differently?
DocMAX said:
which agps file?
Click to expand...
Click to collapse
xtra.bin in \Windows directory I believe
one way to verify if the problem is due to the AGPS corrupted file, is if you encounter the problem, delete the xtra.bin and see if the problem goes away.
kiwiandy said:
My X1i doesnt have an "adavanced configuration tool" application. Is this a 3rd party addon that you have installed, or is my device just configured differently?
Click to expand...
Click to collapse
you have to download it http://forum.xda-developers.com/showthread.php?t=317070
it's our swiss army knife, but be careful
I think people may be getting confused between a-gps and what quickgps does.
My take on this is:
QuickGps downloads a file which contains a list of satellites to speed up getting a signal. Works very well on the x1
this is governed by HKLM/Software/HTC/QuickGPS
A-gps gets an approximate location from your cell tower and feeds 6 virtual satellites signals through the com port set up in the control panel.
It constantly does this, using memory-map software you can see that the signal drops and comes back every second or so. it seems to overwrite what is actually coming from the gps chip as I've seen 4 high quality satellite signals disappear to be replaced with 6 from the a-gps nowhere near where I was.
There's a setting in the registry section concerning A-gps which has "GPSmode" which is set to 2 I wonder what the other values are and do, I havent played with those yet.
You can change the refresh interval I set mine to be 5 when on foot
HKLM/Software/HTC/SUPL_AGPS
I agree with pretty much what you have said (the difference between Quick GPS [sometimes also known as Assisted/A-GPS] and the conventional, location-based AGPS)
However, I don't believe, unless somebody scientifically, or empirically prove, that the phone will receive virtual satellite feed/signal once it acquire the proximity based on the LBS signal. Because to do that, you need to have a data carrier, and it's either via GPRS/UMTS data connectivity (not possible since I would have noticed the data transmission), or radio frequency that satellites transmit on. It can't be GSM/W-CDMA since they operate on the different frequency as GPS, or if it indeed transmit the "virtual satellite signal" on the GSM/W-CDMA network, then I'm sure you will notice it as part of your monthly telco billing?
You may argue that the server is transmitting the virtual satellite signal on the GPS radio frequency, if so, that'll be new development in the AGPS technology since HP iPAQ 6515 first come out employ. However, there are few consideration point;
1. GPS radio frequency does not operate well across barriers, which means the 'virtual satellite transmitter' must be transmitting at a higher ground otherwise it won't work
2. The GPS receiver must be able to reconcile signal from virtual satellite signal and 'real' satellite signal, which means added layer of processing at the phone end, which in my opinions offer more complexity than effective solution.
That said, I just read that the Quick GPS service provider supports 50bit navigation raw data streaming, so I might be wrong afterall.
fards said:
I think people may be getting confused between a-gps and what quickgps does.
My take on this is:
QuickGps downloads a file which contains a list of satellites to speed up getting a signal. Works very well on the x1
this is governed by HKLM/Software/HTC/QuickGPS
A-gps gets an approximate location from your cell tower and feeds 6 virtual satellites signals through the com port set up in the control panel.
It constantly does this, using memory-map software you can see that the signal drops and comes back every second or so. it seems to overwrite what is actually coming from the gps chip as I've seen 4 high quality satellite signals disappear to be replaced with 6 from the a-gps nowhere near where I was.
There's a setting in the registry section concerning A-gps which has "GPSmode" which is set to 2 I wonder what the other values are and do, I havent played with those yet.
You can change the refresh interval I set mine to be 5 when on foot
HKLM/Software/HTC/SUPL_AGPS
Click to expand...
Click to collapse
zenkinz said:
I agree with pretty much what you have said (the difference between Quick GPS [sometimes also known as Assisted/A-GPS] and the conventional, location-based AGPS)
However, I don't believe, unless somebody scientifically, or empirically prove, that the phone will receive virtual satellite feed/signal once it acquire the proximity based on the LBS signal. Because to do that, you need to have a data carrier, and it's either via GPRS/UMTS data connectivity (not possible since I would have noticed the data transmission)
Click to expand...
Click to collapse
when you enable a-gps in the registry it establishes a data connection, or at least it does on my phone.
In my house I get a variable signal, it can drop the data connection easily (and does)!
When I first tried A-gps enabled in the registry it tried to connect, couldnt and memory-map reported no signal. It then connected I got 6 satellites listed till the data connection dropped. This makes me think it's using a data connection.
I disabled all data connections using paul modacos "nodata" and didn't get any "satellites" picked up. My quickgps was upto date at the time and outside I would expect to get a decent "proper" satellite lock.
the SUPL-AGPS section of the registry also contains the following.
Server IP 10.1.101.63
Server Port 7275
Which suggests some form of data connection. Remember this has nothing to do with quickgps or the ephemeris data that gets.
Have a look at http://wmexperts.com/articles/gps_vs_agps_a_quick_tutorial.html
&
http://en.wikipedia.org/wiki/GPS_Phone
A typical A-GPS-enabled cell phone will use a data connection (internet, or other) to contact the assistance server.
Click to expand...
Click to collapse
-----------------------
edit Have just tried again to confirm what I wrote and not getting anything through a-gps at all! I wonder if there's something in this custom rom that's changed things.
But I am being told Ive got a HDop of 666.6m which is a bit spooky..
step outside and I got 9 satellites with 8m hdop back inside and I'm getting standard fix 5 sats 2m HDop flashing on and off every second (signal/no signal) but no data connection being used, so it looks like I'm wrong, so I'll take it all back!
Need to work out what's going on now..
I was having this same issue. At least its good that its not just my device. I tried deleting xtra.bin from both \windows and \temp and it did not help.
Just some clarification on QuickGPS and AGPS. For a regular stand alone GPS to connect, when it first finds a satellite it must download ephemeris data. The ephemeris data contains info about where all the GPS sats currently are in the sky. The ephemeris data is broadcasted by every satellite periodically. A regular GPS must wait for the beginning of the next transmission. If signal is lost mid transmission, the GPS reciever must wait for the next transmission and start all over again. Only once this data is downloaded can a lock begin to be calculated. What quickGPS does is download the ephemeris data from the internet so that next time you request a gps lock, this sometimes lengthy process can be skipped. quickGPS downloads a file called packed ephemeris and places it I believe in the windows directory.
AGPS on the other hand simply supplements info from the sattellites with info from the cell network. What towers you are currently near gives an approximate location (the mechanism that google my location uses) which then tells you which satellites to look for. When fards said it feeds virtual satellite info, he doesn't mean it actually broadcasts fake satellites via RF. It just feeds extra info to the GPS driver. Also, there are lots of calculations to do to maintain a lock. Once the receiver is getting sattelite signals it can send this information over the internet to the AGPS server which is a much more powerful computer that can do these calculations much faster. The server calculates the lock for you then sends you your position information back over the internet. This is why apgs enables a data connection.
Why does my GPS never find a satellite and what can I do to fix it?
Google Maps doesn't get a GPS signal. Footprints, etc. Nothing.
Anyone have a suggestion?
Is it just indoors or are you having problems outside as well? Oh and I assume you've turned on "use gps" in Google Maps options? If you haven't already, download satellite location data (quick GPS) and see if that helps
How long have you wait before you came to the conclusion it doesnt work?
Yes, indoors. I have not tried outdoors yet. I have only waited about 5 minutes. How long should I wait?
Do they typically not work well indoors?
Its unlikey that it would work indoors, try outside.
the signals from gp satellites is part of the visible wavelength, so is affected by things like thick cloud (especially mist/fog) trees and buildings.
whilst you can sometimes get a fix indoors, mostly you can't, or only a weak signal.
to test if it is working go outside with a decent clear view of the sky.
Mine is slow but works
I have dutty 1.4. On average, it'll lock in about 9-10 satellites within 10sec on either Gmaps or TomTom. Even when im in the kitchen (right in the middle of the house), it'll manage to lock in about 4-5 satellites
lude219 said:
I have dutty 1.4. On average, it'll lock in about 9-10 satellites within 10sec on either Gmaps or TomTom. Even when im in the kitchen (right in the middle of the house), it'll manage to lock in about 4-5 satellites
Click to expand...
Click to collapse
same here but not 10sec more like <30sec but only with quickgps data otherwise it takes 1-2 minutes
tried setting polling to 500 (if not allready) in registry?
Try updating the satellite locations from internet.
Run the application "QuickGPS" from Start -> Tools > QuickGPS and then press "Download".
Quick GPS can speed up the time for determining your GPS position by downloading latest satellite data via an internet connection.
The next time you will use the GPS signal acquisition (Cold Startup) will be much faster.
ok after a while on my new HD2 , i have fathomed out that you need the version 7.916.9189 , which works a treat.... then in setting , slect all settings and disable a-gps and location sensing... then fire up tomtom ... you will after 5 mins max ( outdoors) , will pick up satelites... any other versions conflict with the bt stack and also the gps built into the phone.... good luck
I am trying not to write anything offensive but I find it hard to believe this is serious thread???! You're not aware that GPS stands for global positioning system and works by receiving radio signals from overhead satellites?
The satellite bit should give you a clue that it wouldn't work too well indoors. Go outside and see how fast you get a fix, then come back and give us your findings.
Do you want to have very fast lockon, near full GPS reception on your HD2?
Try this, Go to settings - Location - AGPS Service and turn AGPS Service OFF!!
It seems that if you are using CoPilot Live 8 with AGPS Service turned ON, it has a firewall setting blocking it. My CoPilot would freeze everytime it was looking for a GPS signal with it enabled until it had found a signal - up to 5 mins waiting time then it would be fine. When i turned AGPS Service OFF, i had instant GPS reception on all my programs that had GPS. Example, HTC Footprints, CoPilot Live, GPSed - Everything
So i hope this helps you out because it has certainly has made my day
Please let me know if this helps you.
Have a great day
krico said:
Do you want to have very fast lockon, near full GPS reception on your HD2?
Try this, Go to settings - Location - AGPS Service and turn AGPS Service OFF!!
It seems that if you are using CoPilot Live 8 with AGPS Service turned ON, it has a firewall setting blocking it. My CoPilot would freeze everytime it was looking for a GPS signal with it enabled until it had found a signal - up to 5 mins waiting time then it would be fine. When i turned AGPS Service OFF, i had instant GPS reception on all my programs that had GPS. Example, HTC Footprints, CoPilot Live, GPSed - Everything
So i hope this helps you out because it has certainly has made my day
Please let me know if this helps you.
Have a great day
Click to expand...
Click to collapse
I use Co-Pilot 8 and it locks on instantly (within 5 seconds) with A-GPS on. Not to mention the other GPS prgrams I have for sports, geocaching and google maps?
I use copilot live 8 also w/ the a-GPS on, locks on pretty quick, no freezing.
Every program I use says no GPS signal, except for the default weather app? :S
U sure ... I thought A-GPS is tools for GPS program detect GPS faster ... b'cos it store satellite positions ..max valid day 6 days.
Correct. I use that (QuickGPS) all the time but what i'm describing is in completly different settings.
Most probably it all depends on what ROM that you're using.
BumAround said:
Most probably it all depends on what ROM that you're using.
Click to expand...
Click to collapse
That,s probably true dude. I'm using the latest Telstra ROM update.
Hey guys no one has had problems with the GPS fix?
Thanks
Nope, it's working great.
Why? Do you have a problem with it?
i tested the GPS as soon as i got it. caught my position within 15 seconds to 10 metres from its first ever try.
jusba64 said:
Hey guys no one has had problems with the GPS fix?
Thanks
Click to expand...
Click to collapse
don't forget to turn on your data connection at all times when using gps (locations or maps) because otherwise, you will not get a gps fix
despite HTC's thourough promotion of the Locations app with "preloaded maps", you still need a data connection to use the locations program. Utterly ridicoulous but heck, what can you do...
matthiasdeblaiser said:
don't forget to turn on your data connection at all times when using gps (locations or maps) because otherwise, you will not get a gps fix
despite HTC's thourough promotion of the Locations app with "preloaded maps", you still need a data connection to use the locations program. Utterly ridicoulous but heck, what can you do...
Click to expand...
Click to collapse
It's not impossible to use Locations without data, it will just take longer to get a GPS fix.
matthiasdeblaiser said:
don't forget to turn on your data connection at all times when using gps (locations or maps) because otherwise, you will not get a gps fix
despite HTC's thourough promotion of the Locations app with "preloaded maps", you still need a data connection to use the locations program. Utterly ridicoulous but heck, what can you do...
Click to expand...
Click to collapse
I'll have to disagree. I only need data connection to get the AGPS data which speeds up fix. After that the Locations app works fine, even with data turned off. Have you downloaded maps to your SD card?
Well...
I am not sure if I i have a problem, but this is my situation:
Both me and my girlfriend own a DHD.
I have installed copilot on both devices and when I turn on copilot and turn on gps (but have data connection disabled), her GPS fix takes about 30 seconders - 2 minutes, and mine may take > 15 minutes.
Surely 15 minutes should not be acceptable, even with data turned of ,right??
paulus_01 said:
Well...
I am not sure if I i have a problem, but this is my situation:
Both me and my girlfriend own a DHD.
I have installed copilot on both devices and when I turn on copilot and turn on gps (but have data connection disabled), her GPS fix takes about 30 seconders - 2 minutes, and mine may take > 15 minutes.
Surely 15 minutes should not be acceptable, even with data turned of ,right??
Click to expand...
Click to collapse
Try downloading Gps Status from the market. Use it to reset your AGPS data and download new one. See if it makes any difference.
olivierlee said:
Try downloading Gps Status from the market. Use it to reset your AGPS data and download new one. See if it makes any difference.
Click to expand...
Click to collapse
Thx, will have a look when I am at home and let you know if it helped.
It can improve the GPS fix, even if I do not turn on the data connection thereafter?
i had a problem with the lock. i went to the market place and got a normal gps satelite info applcaition. i then waitied for about 20 minutes for it to get a fix(first time) when i then opened HTC locations it worked properly and gets a fix really fast. i guess its just the first time.
SO if you are not getting a fix, WAIT a while for the first time maybe even 30 mins and then it will be fine.
BTW, my GPS fix issue has now been solved....do not know why, but at least it fixes within 1-2 mins or so...
Sometimes it's all about waiting. GPS locating can be very dodgy since it depends on too many factors and is initially a veeeery old technology.
I heard that soon tho EU will launch their own positioning sistem (Galileo - worth 3.4 billion;] ) that's accurate to the meter and since in some way will cooperate with NAVSTAR ( the US current GPS ) will hopefully have better "reception".
Until then - we wait and rely on bloody AGPS
Hi,When I use my phone for finding my location without using data connectivity - without relying on A-GPS so my phone finds my location after a lot of time or sometimes google maps can't find my location.
How can I solve this?
Thanks.
After day or so it won't get fix at all. Samsung just did something wrong I'm afraid. Looks like the GPS in SG2 NEEDS data to work. I found the hard way on my trip to Japan. I know no solution.
So I cant change my gps settings?
Sent from my GT-I9100 using XDA App
GPS in the S2 is weird. Some days it locks in seconds other times it takes forever. I never use A-GPS.
Today I couldn't get it to lock but last night it was instant. So I restored a CWM backup from last night, rebooted and it locked instantly.
I played around with MIUI for a couple of days and found lock time much better than stock or custom rom.
Also, changing server with fasterfix makes no difference when its having problems locking.
I just don't get it.
Sent from my GT-I9100 using XDA Premium App
GPS Aids in Market. It will take a bit of time on first lock but from then it will be fast.
sxi200 said:
GPS in the S2 is weird. Some days it locks in seconds other times it takes forever. I never use A-GPS.
Today I couldn't get it to lock but last night it was instant. So I restored a CWM backup from last night, rebooted and it locked instantly.
I played around with MIUI for a couple of days and found lock time much better than stock or custom rom.
Also, changing server with fasterfix makes no difference when its having problems locking.
I just don't get it.
Sent from my GT-I9100 using XDA Premium App
Click to expand...
Click to collapse
How do you 'never use AGPS' ? Btw. my problem is not time of the lock. But the fact, that without network, I don't get fix AT ALL. With network AGPS reset helps (many apps can do that). But without network GPS works only for some time (AGPS data still valid). After that you just won't get fix. It even looks like wifi connection won't help, it has to be mobile network.
It's because of crappy gps reciever or it can be improved by another rom?
Thanks
Sent from my GT-I9100 using XDA App
It seems the problem is that GPS is in mode, where it simply relies on AGPS. In older ROMs there was app called LBSTestMode where you could change the mode to stand alone, or just AGPS based. This application is not in newer ROMs, so it cannot be switched. It clearly is just a software thing. Except it looks that there is no solution which does not involve flashing roms and/or rooting.
Dr.Sid said:
How do you 'never use AGPS' ? Btw. my problem is not time of the lock. But the fact, that without network, I don't get fix AT ALL. With network AGPS reset helps (many apps can do that). But without network GPS works only for some time (AGPS data still valid). After that you just won't get fix. It even looks like wifi connection won't help, it has to be mobile network.
Click to expand...
Click to collapse
Yeah I never use it. I don't tick 'use wireless networks' at all. To me that's fake GPS.
Since my last post, GPS has been perfect. Am able to lock up to 11 satellites sitting on the couch. On average it takes about 10 seconds to lock. Tested it at least 20 times today.
But who knows what will happen tomorrow!!!
Man, if you can only get a lock using wireless networks then I think your GPS might be stuffed.
Sent from my GT-I9100 using XDA Premium App
sxi200 said:
Yeah I never use it. I don't tick 'use wireless networks' at all. To me that's fake GPS.
Since my last post, GPS has been perfect. Am able to lock up to 11 satellites sitting on the couch. On average it takes about 10 seconds to lock. Tested it at least 20 times today.
But who knows what will happen tomorrow!!!
Man, if you can only get a lock using wireless networks then I think your GPS might be stuffed.
Sent from my GT-I9100 using XDA Premium App
Click to expand...
Click to collapse
That does not mean you don't use AGPS. AGPS is method, where data about GPS satellites are not downloaded from those satellites via GPS receiver, but rather from server via. mobile network. So I'm afraid you do use AGPS, unless you disable mobile networking (and wait about day for current data to become obsolete).
One thing I've noticed is that when I run Z-DeviceTest and bring up the GPS status display, it shows that none of the satellites have almanac data, and very rarely have ephemeris data. If that's accurate, that would suggest that if you've turned off AGPS and mobile networking, you could have some trouble.
3waygeek said:
One thing I've noticed is that when I run Z-DeviceTest and bring up the GPS status display, it shows that none of the satellites have almanac data, and very rarely have ephemeris data. If that's accurate, that would suggest that if you've turned off AGPS and mobile networking, you could have some trouble.
Click to expand...
Click to collapse
Nice find. First app I know which shows this. Now I can test if that almanac is downloading via GPS satellites or not.
Dr.Sid said:
That does not mean you don't use AGPS. AGPS is method, where data about GPS satellites are not downloaded from those satellites via GPS receiver, but rather from server via. mobile network. So I'm afraid you do use AGPS, unless you disable mobile networking (and wait about day for current data to become obsolete).
Click to expand...
Click to collapse
Ok. So does that would mean it's impossible to get a GPS lock without data enabled? Or just harder to?
Maybe I shouldn't have mentioned AGPS, but instead wireless networks which show your position even though GPS is not locked.
Sent from my GT-I9100 using XDA Premium App
sxi200 said:
Ok. So does that would mean it's impossible to get a GPS lock without data enabled? Or just harder to?
Maybe I shouldn't have mentioned AGPS, but instead wireless networks which show your position even though GPS is not locked.
Sent from my GT-I9100 using XDA Premium App
Click to expand...
Click to collapse
It seems it may vary with ROM, and it is possible to switch it, at least older ROMs contain service menu module (LbsTestMode) to switch it. But my SG2 seems to be unable to get a fix without network. It simply does not even try do download Almanac or Ephemerides data from the satellites.
Also for AGPS, mobile network must be used, not WiFi. As I understand it, those AGPS server names are virtual, and network provider redirects them based on location .. which is not possible via WiFi.
I wonder WHY there is such option at all. Do mobile network providers want us to be unable to get a fix without them ?
Dr.Sid said:
It seems it may vary with ROM, and it is possible to switch it, at least older ROMs contain service menu module (LbsTestMode) to switch it. But my SG2 seems to be unable to get a fix without network. It simply does not even try do download Almanac or Ephemerides data from the satellites.
Also for AGPS, mobile network must be used, not WiFi. As I understand it, those AGPS server names are virtual, and network provider redirects them based on location .. which is not possible via WiFi.
I wonder WHY there is such option at all. Do mobile network providers want us to be unable to get a fix without them ?
Click to expand...
Click to collapse
Hey Dr, I think you have diagnosed my problem
Every so often I turn off data and use only wifi. One day my GPS locks in seconds then the next it takes forever.
So I have now tested it a couple of times over the last couple of days, when I can't get a lock I turn off wifi and turn on data. All of a sudden GPS locks again. Interesting!!
Hopefully that is it. Will test again the next time it won't lock.
Sent from my GT-I9100 using XDA Premium App
Ha ! Breakthrough. I could get a fix without network ! But ..
I used newer version of 'GPS Status' app. It shows state of unconnected satellites with gray/blue/yellow based on how much data it has - none/almanac/ephemerides. So you can see if there is some progress or not.
So I disabled network (both wifi and mobile), disabled location from mobile network, left just GPS on .. run GPS status and used 'Reset AGPS'.
The connection has few 'phases':
1) you get signals from satellites .. you see it in power meter .. all are gray .. and their dots on the 'sky' view are all in the N. Sure, GPS does not know where the satellites are, and does not know where you are .. so it can't know where on the 'sky' they should show.
2) Some signals/dots turn blue. That means you have almanac data. Rough position of all satellites, which is transmitted by all satellites. That already means your GPS receiver was used to download some data from the satellites. Based on this, GPS can tell very roughly where you are, and will paint dots on the skyview.
3) Some signals/dots turn yellow. That means you successfully downloaded ephemerides data from that satellite, and it can be used in fix. Have enough of them, and you are done.
4) Some signals/dots turn green - you have fix. The error will get better over time as more satellites are used.
I took me over 5 minutes .. but thanks to this tool I could see I'm indeed receiving some data and there is some progress. Also it only worked outside, under open skies. I tried that in a car, in a bus, in a train .. after 10 minutes I did not get over phase 1. With AGPS I get fix in all such situations in few seconds.
It just looks like the data decoding module for almanac/ephemerides is not the same as for the time (which is used in fix itself). While time channel is quite sensitive and fine, data channel seems to have troubles with even slightest disturbances.
Still I'm happy I made it work in the end !
Btw. the fact that AGPS does not work over WiFi still holds.
ayosopov said:
Hi,When I use my phone for finding my location without using data connectivity - without relying on A-GPS so my phone finds my location after a lot of time or sometimes google maps can't find my location.
How can I solve this?
Thanks.
Click to expand...
Click to collapse
try fasterfix from market
I rarely have the data connection on (just to save battery) and WiFi is only on where I know I have a known connection - thus it is off when outside.
I put on the GPS then immediately run Sygic satnav program. I will have a fix normally within 30 seconds and a worst case of about a minute (that I can remember).
I have just tried switching off and on my phone, putting on the GPS (from the Pull down menu) and run Sygic. From switching on the GPS, I had a lock in about a minute.
KI3 Stock ROM
fred_up said:
I rarely have the data connection on (just to save battery) and WiFi is only on where I know I have a known connection - thus it is off when outside.
I put on the GPS then immediately run Sygic satnav program. I will have a fix normally within 30 seconds and a worst case of about a minute (that I can remember).
I have just tried switching off and on my phone, putting on the GPS (from the Pull down menu) and run Sygic. From switching on the GPS, I had a lock in about a minute.
KI3 Stock ROM
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Could you try that with AGPS manually reset ? I recommend 'GPS Status' tool to do it, it's in 'tools' menu.
GPS lock time seems much improved in KJ4 firmware for me (i'm on orange 2.3.5)
all three DOP values in GPS Status now show figures (instead of infinity for two of them), and i'm getting reported accuracies of around 5 metres, instead of 14 - 20 metres on the older firmware.