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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.
Hi all,
I didnt want to start a new thread, but after searching the forums and google for a long time, i decided to bring it up
So ive had my HD2 for about 2 days now, and I recently installed GarminXT (I used to have it on my Nokia N82)
the problem i'm finding is that the GPS doesnt lock as fast as i thought it would be..
GarminXT has not been locking on (little over 5 minutes now)
I'm a noob to Windows Mobile and HTC so please bear with me!
1. How do i know A-GPS is working? Is it automatically enabled? (This wasnt the case for Nokia as you could manually turn off A-GPS and use strictly GPS signal). Under Location settings i have "Location Service Settings" = ON
and HTC Location Service = ON
2. Im still not 100% sure what QuickGPS does. I've read about it , but all i concluded was that it uses your data to get a faster GPS lock.
So i tried running QuickGPS and it updates no problem.
I open GarminXT and it doesnt lock on. Do i need to use this?
3. Can someone tell me if these are the optimal GPS settings? I kept searching around the forum but cant find one specific to the HD2.
So under "All Settings" > System > External GPS
Programs Tab > GPS Program Port = COM4
Hardware Tab > GPS Hardware Port = None > Baud rate = 4800
Access Tab > Managa GPS Auto = Checked
Are these settings correct? Or are there "tweaks" to it that I can change?
4. One last question:
Under GarminXT, i have the ability to choose 3 GPS options:
"Use Bluetooth GPS"
"Use GPS Intermediate Driver" = Checked
"Use Serial GPS" > Once selected, i get 4 other options to choose:
COM1: Bluetooth Serial Port
COM2: Bluetooth Serial Port
COM4: COM4:
COM9: 7500 COM port
Does anyone know if i should be checked on "Use GPS Intermediate Driver" or if i should be checking off "Serial GPS" > COM 4?
This is my first WinMo device with a data plan (I'm on EDGE speeds cause I'm in Canada), but I always had the impression AGPS would really help the lock times.
Anyone with help would be GREATLY appreciated!
Again, loving the new HD2
Thanks
For GarminXT, use intermediate driver.
For Google maps, use Com4, 4800 rate, that enables use of the compass.
Quick GPS should increase startup, and so far I had all fixes on HD2 under 30 seconds, and I did not change anything.
Normally GPS would download information about orbits of satellites from the satellites. That can take time, as it is one way communication and GPS can't ask satellite to send data again in case of error, it must wait untill the satellite starts sending them again by itself.
It is much faster to get that data via network .. and that is exactly what QuickGPS is for. Problem is that at least on my previous X1 there were many problems with it. The data from network was sometimes completely wrong, and you had to delete the file manually. That information is in temp\xtra.bin. Try to delete it and try again. QuickGPS does not test existence of the file, it will download new one in predefined time.
I'm still a bit confused about aGPS. I'm not sure what it is. Some people state it is the same thing as QuickGPS. Some say it is something to get quick basic fix based on BTS. But I haven't seen that in any application, except Google maps, and they seem to use their own technology and data for that.
But AFAIK, those 'location services' is generally Google's 'my location' exposed for other HTC applications.
I set it on max rate, do i do a mistake? I think that this is setting the speed or Im wrong?! Im connecting with sattelites below 15sec, with no other tweaks or quickgps...
^^
what's "max rate"?
btw, thanks for the replies
i'll look into deleting the cache file for QuickGPS and see if it does anything
Quick GPS allows you to download a weeks worth of GPS satellite position data (almanac data) at one time, helpful if for example you don't have a data plan - you can get your A-GPS data in one hit over WiFi. It helps speed lock time.
Not sure what is happening with yours, mine always locks in Garmin within 7-15 seconds, I have Quick GPS set to autoupdate, but otherwise no special tweaks or modifications where GPS is concerned.
Same here - in fact, the HD2's locking faster to GPS than my Touch HD ever did. I'm getting locks in the garage now whereas before I had none with my Touch HD. Haven't touched the default WM GPS settings or the Garmin one at all since I upgraded to the HD2.
GPs lover-Google map hater
Hi guys, firstly thanks for this thread as i too look for answer...and find some only here
i had the Diamond and now the HD2 and share the love.
Garmin maps are much more accurate and have even the smallest unpaved roads which Google map lacks. Google is so basic maps, i simply hate it...sorry Google...not to mention that it cost money to be online all the time
HD2 GPS confuse me. Sorry if I ask u basic staff but could not figure it up myself:
1. using the GPS w/google map, how u set simple setting, as: "north up" or ""track up" Route setting such as "faster time" or any other basic settings that I always had on my Garmin GPS including Garmin mobile XT?
2. What happend to voice navigation wiith google?
3. Reading your info, does it means that I can install Garmin mobile XT I got with Diamond on HD2 ?
4. Anybody know TomTom for HD2 (which I will get shotly from HTC?
I trust someone out here is smarter than me and will come to rescue
hey guys,
my HD2 is fine now, usually i just do a QuickGPS connect before opening Garmin XT and now it connects SUPER fast...usually under 10 seconds
Thanks for all the help!!
Google is not, and does not set out to be a full satellite navigation prpgram, so it doesn't have stuff such as 'North Up', 'Track Up' etc, nor does it have spoken directions.
For these you need a dedicated SatNav program like Garmin, TomTom, CoPilot or iGO8 which are all 'paid-for' applications.
TomTom will run fine but TomTom don't officially support it, meaning you can't download the correct vesion direct from their website. There are easy ways around this though!
With regard to some of the earlier posts- the HD2 can aquire a fix faster than any other device I've used (and I've used a lot!). I find QuickGPS makes very little difference, but as it uses only a small amaount of data I keep it updated.
QuickGPS and A-GPS are not the same thing, though there are quite a few different definitions of A-GPS. Genuine A-GPS is not used in UK, nor as far as I know anywhere else in Europe except by dedicated programs and platforms set up with the infrastructure (such as Apple, who use it to enhance the poor performance of the iPhone's GPS chip). It is used in the Far East, and works by enhancing your accuracy of positioning by using the data channels to send your current cell ID plus any other availble stuff like WiFi hotspot info, which is correlated to a database of locations, and sent back as an approximate position to the phone. Google Maps uses something like this if a GPS signal is not available- the 'Locate Me' feature will show you in a radius of around 1km.
The Baud rate makes no ostensible difference to the lock times or accuracy, as the data stream from the satellites is far lower than even the lowest baud rate. The NMEA default is 4800, and most software is happy to connect at that rate.
The google maps GPS finds me within 80 metres.. that's not accurate right? cause it puts it on wrong street technically.. When I first got it it did 800 metres =/
WOW, that was fast, thank you NeilM.
I will get Tomtom for free from HTC as it is included with Thai purchaded HD2.
Meanwhile I will try to load Garmin XT that I got with My Diamond at the time, let's see if the activation works...
As for Goole, well, I get 60 meter accuracy at the best, that make ones totaly lost in a city and for sure miss a turn, what a pity.
Thanks again for ever so fast reply.
When Google Maps is started it is finding your position throught the carrier's network and that is why it is not acurate at all. There is an option however, named "Use the GPS" in goolge maps and it becomes as acurate as any other navigation software It just have to engage an GPS lock as the others so do not blame google on this one Hence, you are not using the GPS when you get the inacurate positioning For the maps however you still have to be online But if you pay for your Garmin, iGo maps it would be that expensive and you can use it wherever you are ...
You absolutly right. i did use the "use gps" and it's accurate. The thing is that as heavy GPS user the lack of detailed info on google maps, and the inability to set the maps at your convinient (such as "track up" for example) it's nearly a secure way to go crazy while nevigating, specially off road...try to tilt your head to understand your position in real time when you turning and turning. Thanks for the gps tip.
I agree. Curent version of Google Maps is not suitable for navigation while driving indeed! It can help you get orientated sometimes or if you are looking for something big iGo and Garmin are in a whole new league of navigation sofware for now. However, the new version of Google Maps should be at least as good as the others but it is only available for Android at the moment and I dont see it coming to WM any time soon so we will have to stick to iGo, Garmin, TomTom and the others. I'm not using Google Maps for navigation at all by the way so It wouldn't be so difficult for me )
ragelord said:
the new version of Google Maps should be at least as good as the others but it is only available for Android at the moment and I dont see it coming to WM
Click to expand...
Click to collapse
It's called google navigation, not google maps - and it seems to kill every GPS program available today (thank god).
hey guys,
on the same topic, but different nav software. i use iGO 8, can someone please tell me what the optimal setting are for port and baud rate? i did the auto-detect and the signal is a little on/off.
also... is there a way to get iGO 8 to use the HD2s compass? i like the stand-alone compass of the HD2, but i think it would be swell to be able to have iGO's compass function working aswell.
sorry if this has been discussed before, if there is another thread i should be reading... please direct me there.
thanks for all your help.
cheers.
conscept said:
The google maps GPS finds me within 80 metres.. that's not accurate right? cause it puts it on wrong street technically.. When I first got it it did 800 metres =/
Click to expand...
Click to collapse
Eh, if I'm not wrong, that's agps at work.
It'll find you with the nearest base station. then slowly try to triangulate you. Normally, you'll be in an area with only 1 base station, so there's not much triangulation going on.
When I'm in city, it's pretty accurate. I get my approx distance within a couple of seconds, wait another 10 - 20 secs to get gps fix.
A-Gps and other things
A-GPS is just one thing: Assisted GPS. It is a toggle-- when you toggle it on, in your phone's settings, you will get the locational assistance of the cell towers. That is the towers them selves, two or more towers and your phone triangulate to give an approximation of your location. GPS also uses triangulation (derived from simple trigonometry equations) to determine your location and is much more accurate. In fact it can be ever more accurate as your device locks onto more satellites. I have found that the best thing to do is to turn off A-GPS. I don't know what it is but Googlemaps seems to have a terrible time locking onto satellites on Windows Mobile. But I have found, especially on Android 1.6 and above you get very rapid locks so long as you wipe out the telenav program. I strongly suspect that Google is undermining Windows Mobile in favor of supporting their Android system. They have turn by turn for Android but not for Windows Mobile and it seems like they are also building it not to lock sats nearly as well. You can force it to get moving by pre opening the GPS or other methods just prior to running google maps.
I think everyone should write google and tell them to fully support Windows Mobile (Phone)... T-Mobile is just about set to come out with the HTC HD2 in about a week (March 24th) and I intend to get one. I am not happy that it doesn't have a physical keyboard cloned from the Touch Pro 2, but I expect to like most of the rest of it.
Turning Location on is another thing. You are henceforth allowing all applications to know and your location. this can be helpful but it can also be a potential privacy risk. Of course it's easy to turn off and on. You might want to read the fine print.
Actually, I have a more basic question. Is there a soft "switch" or software application to actually turn the GPS on? On my HD2 I have a few GPS apps and all of them report the GPS being on or "no GPS Device found". Even Goggle maps, if I siwtch to USE GPS mode, keeps endlessly waiting for a GPS signal and then nothing happens. What am I doing wrong?
Thanks much
Gps htc hd2
In my experience with windows mobiles and internal gps, manage gps automatically is best and no ports should be assigned at all unless using bluetooth gps receiver! Also, sounds crazy too many but no every location on this big earth is withing available to public gps devices gps satelite paths (satelites going around the earth!) Make sure your outside the house or flat before thinking your gps ain't picking up. My hd2 is fast, my old mda3 was too and worked better inside but thats down to i was living in a different location at the time and at an higher altitude i would say. 1 of many other reasons could be that the military could be using the sat at the time which would render it unavail to public (offline)!
Hi all,
I did search the "General" Forum, but didn't find much. Today I tried the built-in GPS for the first time, with demo versions from copilot and Navigon mobile navigator. Weather condition was cloudy/foggy (1000m/3000ft cloud base, "Hochnebel") and it was snoming a bit. Bluetooth and WLAN were turned off. AGPS had a recent update.
Unfortunately, the system was unusable. The gps got a fix after about 10 seconds with 7 to 8 satelites in range; but basicly trouble was that it was lagging and skipping a lot. I don't mean serial communication, both programs reported position updates every second, as it's supposed to be.
But in the raw output speed jumped from 0 to 100kph every 5 seconds (I was diving 100kph constantly) and position updates were sometimes fluent but then again only every 3 seconds a new position (= 3 times same NMEA packet). Obviously this confused the nav software(s) a lot.
In addition to that the GPS position is reported incorrectly 300m to the south. I can reproduce the error constantly, If I drive NS direction, it will only report a wrong position on the street, but driving EW is not possible, it will always set the car on parallel streets and will recalculate the route constantly.
Is this a known problem on Leo and is there a fix? Obviously the intermediate driver here in the forum will help with the skipping, but not with the off-position reports.
Thanks, mc7
edit: reload agps data over 3G connection or WLAN. it seems that active sync download corrupts the agps data.
Haven't experienced anything like this myself and I was doing a 160km trip in similar conditions this past Friday so I don't think it's a known fault.
My suggestion would be to try again and if it continues get your set replaced.
Hi. A few things spring to mind from my time selling (dedicated) GPS devices.
Thick Fog/snow clouds block more of a signal than any other type of weather short of trees.
Some types of Tinted/Reflective/Heated windows (especially the type the mondeo use, if I remember correctly) can seriously affect the signal.
The angle that the device is positioned on the dashboard, and hence the angle the GPS antenna presents to the satellites is also critical.
Test the positioning on a fairly clear day, with the phone well exposed to teh sky, and no surrounding trees/houses/tall buildings, and see if the accuracy is still off. If it is, then the gps is dodgy and you should get it replaced. If it is accurate, then start looking for interference in your car.
No lag with copilot here, very accurate road positioning
ahhhh finally, solved again It seems that somehow the agps data got corrupted via activesync synchronisation. I turned off the "download via activesync" option in quickgps and reloaded AGPS data over the 3G connection. Now everything is in working order, no lagging, position accurately aquired, only a bit slow, like 10meters behind actual position. But that I had with my old diamond as well, it's not a draw back. btw, weather conditions were the same...
thanks again for your help.
AGPS has nothing to do with sync. I think you are confusing this with QuickGPS.
pedmond said:
AGPS has nothing to do with sync. I think you are confusing this with QuickGPS.
Click to expand...
Click to collapse
AGPS data (quickgps) can be downloaded via activesync in stead of over-the-air services.
Hmm, I though AGPS wasnt anything to do with QuickGPS.
As I understand it
AGPS uses phone signal to triangulate the phones location
QuickGPS downloads the position of the satellites.
loomx said:
Hmm, I though AGPS wasnt anything to do with QuickGPS.
As I understand it
AGPS uses phone signal to triangulate the phones location
QuickGPS downloads the position of the satellites.
Click to expand...
Click to collapse
AGPS comes in two forms
http://en.wikipedia.org/wiki/AGPS
loomx said:
Hmm, I though AGPS wasnt anything to do with QuickGPS.
As I understand it
AGPS uses phone signal to triangulate the phones location
QuickGPS downloads the position of the satellites.
Click to expand...
Click to collapse
Correct, that's my understanding as well. With the detail that AGPS is actually more than simple triangulation.
Nope, see wikipedia entry on agps. HTC uses satelite data/orbit information provided via internet; it stays accurate for about a week hence the weekly updates. your gps will work without this data, however, since it needs to calculate satelite trajectories by itself it will take longer to get a fix from cold start.
and if this help data was downloaded incorrectly, it obviously is possible that the receiver reports a wrong position. But, as stated, reloading the QuickGPS data and turning off activesync loading of the data solved the issue.
What you mean with triangualation is google maps. it gets the signal strength from neighbouring base stations and their cell ids and looks up their position in a large database online. with the base stations' exakt positions and the signal strength of each one, one is able to estimate the current position through triangulation; however since this method does not account for multipath propagation or reflection off wet walls or similar, it can only be taken as rough estimate.
Hi,
Could anyone please explain the various settings for GPS in the "settings" menu (under "location")? I find that the manual and tooltips are not very informative.
Particularly, I don't understand the difference between the first choice ("wireless networks"?) and the third choice ("assisted GPS"). I understand that the phone may use wifi or mobile network to detect my position (instead of or in addition to GPS satelites), but I don't know which of the two options to choose for this.
Also: When I enable "wireless networks", what does the warning that pops up mean? It mentions that data will be collected even when no software (GPS/map) is running. What is that? And what is the difference between enabling this and the fourth option ("share with google")?
Finally:
Does your GPS immediately start working when you enable it? Myself, I need to enable/disable GPS using the desktop widget and the various GPS settings several times before it managess to find my location. (My position is not the problem - once detected/connected, it works fine.) I still don't understand which combination of settings it is that finally makes the GPS work as expected.
As I understand the first option "Wireless Neworks" will rely entirely on data from Cell Towers e.t.c to determine your position. I guess this will be less accurate.
"Assisted GPS" enables your device to get a faster lock on your location by collecting available data from cell towers first before using the GPS receiver.
I think if you were only to activate the GPS in some circumstances it would take a lot longer to get a fix.
"Share with Google" just allows the gears addon within the browser to share your position with google allowing them to return results based on your location.
That's my take on those options.
"Wireless Neworks" - is using cell towers and wifi to locate you.
Probably they have (or use a 3rd party DB) for that. Anyway, is not (very) accurate.
"Assisted GPS" - i'm not 100% sure but i think is connecting to a location server to get the location of the GPS satellite so, will lock faster (at least this is what my Nokia 5800xm is doing).
The warning message you get is because google will (most likely) use your location (cell towers and wifi spots) to create and update their own database so, phones without GPS will still be able to use google maps.
Well, they probably do something more with that data but who knows what
I just wanna add that using any type of assistance for the gps chip in this phone is (in my personal oppinion) unnecessary. I am sitting inside my house, in my bed(with a window behind me) an in 10sec i get fixed on 10 satellites. Not much that can beat that ;-)
in addition, i am in the bottom floor in a 2floor house so it is alot of roof and cealing between me and the sky.
Sent from my X10i using the XDA mobile application powered by Tapatalk
Thanks for your replies. Much appreciated.
Just curious - which app do you use to monitor GPS satelites?
Also, does everyone's GPS find your location rather quickly after enabling GPS? I usually get the message "Your current position is temporarily unavailable", I retry, same result, I retry, same result ... Only after I disable/enable GPS several times, my position can be found.
My GPS usually finds my position rather quickly first time I switch on GPS. I have aGPS (Assisted GPS) enabled too, this way your phone gets help on locating the sattelites position from your mobile provider, hence locking onto GPS signal faster (is to my understanding).
Plus, if you're standing in an area with tall buildings, your position will be less accuratelly pin-pointed, bouncing GPS signal and all.
I'm using GPS test by chartcross ltd. Avalible in the free android market, and i really like it!
Sent from my X10i using the XDA mobile application powered by Tapatalk
I never turned on A-GPS on this phone. There is no need for A-GPS.
This phone have fastest GPS fix of all phones.
I have noticed when I am running on 3G (H) I get the "location temporarily unavailable" notice, but if I force it to not go to 3G it will be E and I get my location. This holds true if I have setting for using GPS or not.
This seems to be a problem with Google Maps using the data transfer method of 3G (H) versus E.
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.