GPS calibration - Atrix 4G General

I have found that some apps that are location aware or ask me to pick local servers, often suggest servers on the east coast. I am on the west coast of the US. When I am on wifi this does not happen, it is only happening on 3g. When I toggle on wifi is suggests local servers. I have went into location settings and toggled on and off the settings for GPS as well as the "use wireless" option and it does nothing to help the issue.
The maps app as well as navigation work perfectly fine for locating me, this seems to be isolated to apps.

Thats usually an indication your gps is not working. When you use speedtest app with out wifi does it ask you to connect to kansas?

Speed test isn't a good way to find out as it will connect you sometimes to the least busiest server. Gps needs to lock first on a couple sats first time usage after that should be better.
Xda app via atrix

I wad able to get it calibrated correctly. I went outside and calibrated the compass first. I then did a gps lock from maps and then tapped lock again and let it sit for about 2 minutes. Everything is fine as of now.
Sent from my Atrix using XDA App

GPS in Atrix locks the satellite very quick. It could be comparable to a standalone GPS.

Related

Locations not working on my Omnia 7

It worked once when I first tried it but ever since then for example when I go into maps, it's always searching and searching. the local filter in the bing search doesn't work either...
What can I do? Anyone have the same issue?
I've managed to bring up my location but it's highly innacurate. I downloaded the GPS app that is available in the marketplace and it's showing the wrong latitude/longitude coordinates as well.
Highly annoying.
Do you have Weatherbug installed? This app seemed to break my location service too. Sometimes it showed my location a few hundred miles away... I then uninstalled Weatherbug and somehow, after a while, it was working again -strange.
Now it's very accurate and fast.
Then go into settings -> "find my phone" and check the upper box for "saving the location".
It could also be a problem with your carrier -the location service first takes the location via A-GPS which is you provider's responsibility.
GPS might take a few minutes to determine the exact location.
I called 3 and they said I could arrange a door to door exchange but first they advised me to go to the 3 store nearby and use my SIM in another omnia 7 to see if it works.
Surprise surpise, after the call, the GPS is now perfect. I wonder if they did something at their end lol.
So after a few days use, I have come to the conclusion that the GPS doesn't seem to work well indoors, but as soon as I go outdoors, it's tracking me just fine.
digger1985 said:
So after a few days use, I have come to the conclusion that the GPS doesn't seem to work well indoors, but as soon as I go outdoors, it's tracking me just fine.
Click to expand...
Click to collapse
GPS will absolutely NOT work indoors because it needs nearly line-of-sight to the GPS satellites above. The roof of a car might work but the roof of a house won't.
Indoors the phone is using A-GPS, the triangulation of cell towers of your network operator. It's very inaccurate and might get no location at all.
See my post here: http://forum.xda-developers.com/showpost.php?p=9417735&postcount=2

locations and weather widget

Okay so randomly my weather widget stoped working, it's stuck on one location which is 5 miles away from me...it used to work perfectly. I read up a little and seems it's known problem...Any solutions...Yes i've tried hard reset.
Htc Locations and (Google) Maps is brilliant except it doesn't find my exact location...maybe a couple of streets away...
Is this normal? I mean I used to get exactly location when i turn off "Use wireless to find location" and Gps is off...So it's finding location from nothing??? but it found it exact then it can't update and asks me to switch on location settings and once on it can't find the exact location.
I'd be thankful if anyone could elaborate and explain things a little...
I wonder if someone with a wifi network has moved house.... (given that google were using wifi networks (apparantly) for location data - it even suggests as much in the phone's tips when you run through the settings....)./
One thing I would suggest is that just by using cell-tower triangulation the system won't be very accurate. But if you turn on GPS and get more than 3 or 4 satellites connected it should be very accurate.
Riceburner said:
I wonder if someone with a wifi network has moved house.... (given that google were using wifi networks (apparantly) for location data - it even suggests as much in the phone's tips when you run through the settings....)./
One thing I would suggest is that just by using cell-tower triangulation the system won't be very accurate. But if you turn on GPS and get more than 3 or 4 satellites connected it should be very accurate.
Click to expand...
Click to collapse
Nope I'm just using data connection from my providers. no wifi. So You reply states : okay maps and locations wouldn't be very accurate due to no gps...Answers my questions. thanks
Now any ideas on the why the weather widget is only showing one location all the time ( current location )...Which is 5 miles away from me...

[Q] GPS - Does it Really Require Wifi? [SOLVED/ANSWERED]

Does the Tablet Really Require the Wifi to be On to use it? Only way we can get it to work is if we turn the Wifi on and then it uses AGPS.
Downloaded GPS Status and it sorta seems to confirm this. Ive read other sites of people returning the product and getting another and GPS works outta the box w/o Wifi?
Thoughts? Solutions?
--Solved -- Issue seems defective Equipment. GPS works Fine in Airplane Mode with GPS on. Tablet was returned for another and now works.
Haven't checked this, but it seems a bit silly. Why would you need a (static) wifi connection when u use the GPS (for moving around). Doesn't make any sense. I will test this tonight.
spaanplaat said:
Haven't checked this, but it seems a bit silly. Why would you need a (static) wifi connection when u use the GPS (for moving around). Doesn't make any sense. I will test this tonight.
Click to expand...
Click to collapse
With the one we have here I can Confirm the only way i can get it to work is with WiFi on. And Acer Support confirms this..
But there is so much conflicting information out there that Id like to see if it can get cleared up.
If people are returning them and their new ones are working fine with normal GPS then did ACER have a Bad Lot? Or are these folks just making rumors.
I've just quickly checked this with Chartcross GPS Test. With WIFI on I could see one satellite indoors. I switched off WIFI and then saw four satelites, so it would seem that WIFI does not have to be switched on for GPS to work. However, having a data connection is always a good thing to get AGPS data with.
Sent from my A500 using XDA Premium App
From my experiance, no it doesn't . I have been using mine with the wifi off with no problems. I use Copilot Live USA to get around all day at work. One thing is, is that Copilot freezes on me if I try to go into the settings menues.
Acer Says Yes
I chatted with an Acer rep this morning and was informed WIFI or 3G is designed to work with the GPS. GPS will not work if there is no data signal. Being hardheaded I called hoping to find someone with more knowledge on this matter and was told the exact same thing, NO WIFI/3G = NO GPS. With this set back I have decided to return.
But I am curious why some peoples are working and others are not?
Im sure my Buddy will post here soon.
but he called Acer and they are saying that it requires Wifi for GPS by Design.
So if everyone else is able to do it.. and he isnt and Acer says thats the way it should be..
Then either some folks have an "added' feature design flaw or they are Fibbing about it. Or Acer just dont know what they are talking about and my buddy has a defective one.
I do not seem to need to be connected to Wifi for GPS to work. I did notice something interesting while researching this though. 22% of my battery usage was coming from cellular. Thats a huge amount of power being used up to poll for a cellular signal that a wifi device isn't doing anything with.
I added about two hours to my battery life by turning the tablet on Airplane mode and then enabled Wifi. Thankfully the little airplane icon in the status bar is only there for a few seconds
The issue is not GPS need WiFi. It is the map need WiFi or 3G datalink in order to be updated with the GPS signal. Your tablet does not preloaded a map like a portable Garmin or TomTom GPS device does.
The GPS does not require Wifi to work, however if you are using an app like Google Maps, this app DEPENDS on wifi to download map and pois. Google Maps is not like your GPS software on your TomTom or Garmin GPS, it downloads the data using the cell modem or in this case the wifi on the device.
To summarize, if you use an app like Copilot or another GPS app that has maps predownloaded then the GPS works just fine on it's own without Wifi.
I hope this clears it up.
john0dean said:
The issue is not GPS need WiFi. It is the map need WiFi or 3G datalink in order to be updated with the GPS signal. Your tablet does not preloaded a map like a portable Garmin or TomTom GPS device does.
Click to expand...
Click to collapse
Neoprimal said:
The GPS does not require Wifi to work, however if you are using an app like Google Maps, this app DEPENDS on wifi to download map and pois. Google Maps is not like your GPS software on your TomTom or Garmin GPS, it downloads the data using the cell modem or in this case the wifi on the device.
To summarize, if you use an app like Copilot or another GPS app that has maps predownloaded then the GPS works just fine on it's own without Wifi.
I hope this clears it up.
Click to expand...
Click to collapse
Then Why Doesn't Foursquare, Gowalla, Or even the GPS Icon Activate.. Or Even using GPS Status.. Using GPS Status It wont do anything unless WiFi is on.
Totally Understand that you need wifi For Map Downloading. But when you have a Static Predownloaded Map using like MapDroid or Even TomTom Software the Maps are preloaded nothing to download.
So you all Are SERIOUSLY saying that your GPS works Fine with out WiFi I ask you to download GPS Status and Try it with out Wifi Being on and See if you can get your GPS to come on and get a Lock.
Because Acer Support has already said that the GPS is WiFi dependent.
sammyboy405 said:
Then Why Doesn't Foursquare, Gowalla, Or even the GPS Icon Activate.. Or Even using GPS Status.. Using GPS Status It wont do anything unless WiFi is on.
Totally Understand that you need wifi For Map Downloading. But when you have a Static Predownloaded Map using like MapDroid or Even TomTom Software the Maps are preloaded nothing to download.
So you all Are SERIOUSLY saying that your GPS works Fine with out WiFi I ask you to download GPS Status and Try it with out Wifi Being on and See if you can get your GPS to come on and get a Lock.
Because Acer Support has already said that the GPS is WiFi dependent.
Click to expand...
Click to collapse
Ok, this is what I did. Turned off wifi and ran GPS status. It locked on to 3 of 6 sat so I guess it works. With wifi on it seems to locate more sat and locks on quickee.
Just to make sure in settings you do have GPS on under location and security correct?
Reply
I tried using MapDroyd with all preloaded maps, it would not give me a Red X for location until I flipped on wifi. That was the only reason I contacted tech support and both chat and phone told me the same thing. There is no power to the GPS until 3G/WIFI is active. Sounds stupid I know, I like the tablet and what nothing more than to keep it but I just refuse to keep something that is configured in such a way. I can live with the AdHoc issue since I know that can eventually be resolved.
Disclaimer - These are not my words but the words directly from Acer tech support.
Trust me I was very clear that I had maps pre-downloaded and the person on the phone was very clear what they told me about how the hardware was configured.
michaelg1030 - YES
T0yman said:
I tried using MapDroyd with all preloaded maps, it would not give me a Red X for location until I flipped on wifi. That was the only reason I contacted tech support and both chat and phone told me the same thing. There is no power to the GPS until 3G/WIFI is active. Sounds stupid I know, I like the tablet and what nothing more than to keep it but I just refuse to keep something that is configured in such a way. I can live with the AdHoc issue since I know that can eventually be resolved.
Disclaimer - These are not my words but the words directly from Acer tech support.
Trust me I was very clear that I had maps pre-downloaded and the person on the phone was very clear what they told me about how it the hardware was configured.
Click to expand...
Click to collapse
Not sure I believe what they said.
I just did one more test. I turned wifi off. Reset my tablet. Made sure wifi was still off. Opened up GPS Statues and it locked on to 5 of 7 sat in less than a min indoors. I dont have any nav software with maps so I can't test that. If GPS status shows nothing with wifi off for you I'd exchange it for a new one.
sammyboy405 said:
Then Why Doesn't Foursquare, Gowalla, Or even the GPS Icon Activate.. Or Even using GPS Status.. Using GPS Status It wont do anything unless WiFi is on.
Totally Understand that you need wifi For Map Downloading. But when you have a Static Predownloaded Map using like MapDroid or Even TomTom Software the Maps are preloaded nothing to download.
So you all Are SERIOUSLY saying that your GPS works Fine with out WiFi I ask you to download GPS Status and Try it with out Wifi Being on and See if you can get your GPS to come on and get a Lock.
Because Acer Support has already said that the GPS is WiFi dependent.
Click to expand...
Click to collapse
None of those programs work without a data connection. Once you use a program that works without requiring some sort of data, the GPS will work.
I don't really care what Acer says - if you call acer and ask 10 people the same question, there's a possibility you'll get several different answers.
I know what I've experienced, and that is that the gps works with wifi disabled.
I'm confused on what you're debating exactly though, are you saying that the gps does not activate/work without wifi or that it doesn't lock on to satellites?
If you want a simpler test to see if it works/activates simply refresh your weather widget manually and with no wifi connection - you'll see the gps icon pop up and it will say searching for satellites. It won't work, since the weather can't update without data but you'll see that it activates the gps.
In essence, the gps in the A500 works exactly like our cell gps, there's no difference. It's Assisted GPS (aGPS) and requires a data connection to locate the satellites quickly vs. standalone or autonomous GPS found in our Garmin/Tom Tom/etc. Without data it's going to take you 10m-20m to find a lock, with data, 3-5m. This might be what's messing with people. The good thing is if you lock on when you get into your vehicle with help from your wifi for example, then you won't have to wait for it to lock on at some other point. Since my gps is on in the tablet all the time, it's locked in and I suppose that's why I'm not having a problem in my tests.
Another thing to keep in mind is that the GPS in use on these devices uses aGPS (assisted GPS) - which uses a combination of cell tower info (if using 3G) and/or known WiFi hotspot locations to help nail down the starting location and speed up the discovery of satellites.
Y'know, the stuff that Apple & Google are getting in so much trouble for having recently
michaelg1030 said:
Not sure I believe what they said.
I just did one more test. I turned wifi off. Reset my tablet. Made sure wifi was still off. Opened up GPS Statues and it locked on to 5 of 7 sat in less than a min indoors. I dont have any nav software with maps so I can't test that. If GPS status shows nothing with wifi off for you I'd exchange it for a new one.
Click to expand...
Click to collapse
OK I will be heading that way for an exchange and update the info once I am back home. Thanks everyone for your input, like I said I like the tablet but the no GPS thing just never made since.
T0yman said:
OK I will be heading that way for an exchange and update the info once I am back home. Thanks everyone for your input, like I said I like the tablet but the no GPS thing just never made since.
Click to expand...
Click to collapse
Good Luck.
you can get app fasterfix from market t
it worked great for me.
i also can not keeo co-pilot from crashing locking up sent them email hope its fixed
soon
Replacement
Ok I am back home after going to BestBuy and picking up a replacement Acer A500. This one grabs my current location using current setup.
Airplane Mode On
WIFI Off
GPS On
I will be going in to the city tomorrow and run a few more tests, will post a new update after but this is looking promising. Thanks again for the feedback!

[Q] Anyone Elses GPS Aweful?

I have never had my GPS locate me via google maps. My Phone has no issues. Anyone else have GPS issues? any tips? Hopefully a software update fixes it? I have a friend who has the same issue.
[Should have read "awful", not aweful]
Nothing wrong with my gps. Have you upgraded to the latest firmware? Downloaded the A-GPS data (you can get this by using an app called GPS status)? Switch OFF wifi after you do, then leave it to get a full signal lock (takes up to 15minutes or so with a clear view of the sky).
toddmp said:
I have never had my GPS locate me via google maps. My Phone has no issues. Anyone else have GPS issues? any tips? Hopefully a software update fixes it? I have a friend who has the same issue.
[Should have read "awful", not aweful]
Click to expand...
Click to collapse
Make sure you are outside with a clear view of sky when you test. It can take any GPS up to 10 minutes to acquire the ephemeris information (satellite position at a certain time) and lock up. You phone cheats this by using the cellular network to provide a general location of where your are and therefore where to look for certain satellites.
thanks so much for the info guys. I had a feeling it had something to do with no cell phone band helping out. thanks!
GPS works fine here, as other have said the closer you are to the sky/window the better.
yeah..give your TF a few minutes to lock up sat positions (if you've never done this)..
this applies to most pure gps devices..cellphones can use cellular network signal to quickly locate your position but the data isn't really from gps itself.
http://forum.xda-developers.com/showthread.php?t=1088120
Hope this helps
Acid lestitious 2.0. Fugumod 2.4 800 mhz
jerrykur said:
Make sure you are outside with a clear view of sky when you test. It can take any GPS up to 10 minutes to acquire the ephemeris information (satellite position at a certain time) and lock up. You phone cheats this by using the cellular network to provide a general location of where your are and therefore where to look for certain satellites.
Click to expand...
Click to collapse
I wonder if it does the wifi cheat like maps for android phones, where it uses the known APs to determine location? I say that because when I first fired up my transformer yesterday, after connecting to wifi, I screwed around on maps and it found me inside my house in less than 30 seconds.
toddmp said:
I have never had my GPS locate me via google maps. My Phone has no issues. Anyone else have GPS issues? any tips? Hopefully a software update fixes it? I have a friend who has the same issue.
[Should have read "awful", not aweful]
Click to expand...
Click to collapse
its the reverse for me! in the same room of house i often cannot get a fix on my Optimus 2x. i use GPS Staus app. but i often get fix within 30secs. as a test i have both machines running the app next to each other and the transformer always gets regular fixes.
..... hmm just realised as i type this that i have a phone called optimus and tablet called transformer, and they both run android!!!
I get fixes with no wifi (ie: only GPS) within 30 seconds.
Quite the opposite, mine is extremely accurate. After it gets a fix on maps that little google person is standing right in my front yard in the satellite view! Better than my Droid!
Mine is almost instantaneous. Just tried it at home based on this thread and had a read in probably 5 seconds.
I have not been able to obtain a GPS lock until today when I set my location to use wireless networks. To me this is really stupid because the GPS shouldn't have to use any location settings to obtain a lock in my mind. That is if the GPS chip in the TF is a true GPS chip it should not to rely on a wifi signal to obtain a lock. If the GPS is turned on then it should lock.
I tested sygic gps navigation 11 and signal lock and quality was better than my galaxy s was pretty accurate
Sent from my Transformer TF101 using XDA Premium App
Works fine for me, apart from one minor detail. When I switch from Google Maps to another app, even for a few seconds, then the tablet has to get a lock all over again. There appears to be no way to set the GPS to keep a lock while Google Maps isn't the active program.
That, for me, makes Google Maps near-useless in a moving vehicle. Hopefully other third-party apps won't have this issue.
Google Maps is prety much useless on the Transformer for GPS navigation as a data connection is need. I have heard of people caching a route before hand but ..... Copilot Live 7 is out for android so that is one option. However if the GPS relies on a wifi signal in order to obtain a lock then it is about useless too.
toddmp said:
I have never had my GPS locate me via google maps. My Phone has no issues. Anyone else have GPS issues? any tips? Hopefully a software update fixes it? I have a friend who has the same issue.
[Should have read "awful", not aweful]
Click to expand...
Click to collapse
Gps works fine on mine....unlike my icons or Samsung...both returned
gps does use wifi to help gps locate, theres options to turn this off in settings, i went to pick up my dock today and couldn't get a gps lock while in the car with the transformer in my lap(gps status app showed 3 sats but none would lock) just lifting it up 12 inches closer to the windshield made 7 satellites pop up and instantly started getting locks
i think proximity to a window/line of sky is a big factor, and the transformer does have a true gps chip for those who seem to doubt it, also the navigation app keeps running in the background, its better to use that than google maps
No issues with gps here. The bastard finds me every time!
jadesse said:
However if the GPS relies on a wifi signal in order to obtain a lock then it is about useless too.
Click to expand...
Click to collapse
It doesn't rely on WiFi for a lock, it just uses it to allow a faster connection if you don't already have current ephemeris data downloaded. That's a limitation of all GPS receivers -- it takes a fair while to download the ephemeris data if you're out of date or have travelled a significant distance, and without it the device can't get a GPS fix.
You can think of the WiFi location system as analogous to a cellphone being able to use tower locations to help position itself while waiting for GPS ephemeris data.

GPS lock time problem

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
Click to expand...
Click to collapse
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.

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