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New to the forums, and betting this is a stupid Question, but I was wondering if there was anyway to tap into the GPS locater(built in for emergency calls such as 911) and use that for a GPS application, If the Wizard even has one built in, I would imagine that it does, but anways wondering if its possible, and if anyone has any incite into how to use this/turn it on?
There's no GPS in the wizard.
markgamber said:
There's no GPS in the wizard.
Click to expand...
Click to collapse
Emergency services can locate your phone fairly accurately using triangulation from the gsm phone masts, using network data. There was a company selling a tracking service such as this for mobile users a while back, but I forget the details.
yeah ran into that service a while back, but the main way to get to it was to buy two handsets and pay for their cheap data service and put the other handset in someones car or whatever and use the 1st handset to track them...
I think that navizon.com has a program like that. theres a trial version for free. Doesnt google maps also use that technology?
hmm try google map 2.0 they show u wat ur location is without GPS
try http://forum.xda-developers.com/showthread.php?t=349188
I've tried both of these apps and both aren't worth a crap to me. They get my location in the right state, heck even the right city...almost. But I can't get it to be consistent let alone even half right.
I tried em both out and would like to know what I have been doing wrong since everyone else says that they are "great."
Thanks,
Ivan
It's already been said, but get Google Map 2.0...I installed it a few days ago, and it's not bad. I'm usually within 2000ft. of the calculated location.
Bad Karma said:
I've tried both of these apps and both aren't worth a crap to me. They get my location in the right state, heck even the right city...almost. But I can't get it to be consistent let alone even half right.
I tried em both out and would like to know what I have been doing wrong since everyone else says that they are "great."
Click to expand...
Click to collapse
The only thing you did wrong was expect triangulation to work like you're watching CSI. In the real world, there is signal bounce, interference from trees, buildings, and other radio transmissions, and a whole host of other nameless error-creating problems. Radio triangulation is severely limited, but considering this sort of feature wasn't even available as a free application (much less being built into a mapping software as robust as GMaps) until VERY recently, it's pretty good, if you don't have GPS. You can buy a dongle to attach to your MDA, or you can suck it up, and deal with generally inaccurate location.
Trying it again...I thought that I had 2.0 but maybe not...I'll let you know either way how it comes out this time.
-Ivan
Ok much better...however it is still like 4 miles!!! off.
Does it update when in travel or how/when will it become more accurate??
Thanks agian,
Ivan
Google Maps 2 has "My location"
I dunno if you knew but Google Maps has been updated now and it offers My location - which is pretty close what GPS does. It gets your position through cellular towers and then it locates you within half a mile if I'm not mistaken...
Try it and c if it works 4 u
Myrddin Wyllt said:
It's already been said, but get Google Map 2.0...I installed it a few days ago, and it's not bad. I'm usually within 2000ft. of the calculated location.
The only thing you did wrong was expect triangulation to work like you're watching CSI. In the real world, there is signal bounce, interference from trees, buildings, and other radio transmissions, and a whole host of other nameless error-creating problems. Radio triangulation is severely limited, but considering this sort of feature wasn't even available as a free application (much less being built into a mapping software as robust as GMaps) until VERY recently, it's pretty good, if you don't have GPS. You can buy a dongle to attach to your MDA, or you can suck it up, and deal with generally inaccurate location.
Click to expand...
Click to collapse
Actually google maps DOES NOT use triangulation..it will just show ur position based on a single cell tower and the signal strength being calculated by your phone..
So I tried my Google Maps 2.0 on the fly today...
It told me that it wouldn't work because I did not have a "data connection" and that I needed to contact my "service provider" to be able to utilize that function... (Or some crap like that)
What am I doing wrong now??
Thanks guys,
Ivan
I'm trying to develope an application for my Trinity, and I'm currently thinking of implementing a GPS function to track down my current position.
But: I've heard there also are other metods to find out your position, by triangling the GSM-bases, using GPRS-position(???) and also, I've seen a service that uses SMS(??? It says you can send a SMS to a server, and it will find out where you are...=)
Now, which one of these are pure misunderstandings, and which one does work?
I've heard of a application that that uses GSM-bases to triangling the position, and it actually works...
So my second part is, anyone knows how to implement this is C# ?
It can be done...
neofix said:
I've heard there also are other metods to find out your position, by triangling the GSM-bases, using GPRS-position(???)
Click to expand...
Click to collapse
I can't help you on how to do it, but I know an app that does. Google Maps works this way. It finds my location within about 1Km using GPRS. I don't have GSP on my phone. It only works is some locations. For example, at my house (in a rural area) it doesn't work. I am guessing this is either because I have only one base providing service, or that base is missing certain features.
Good luck on finding a solution to implement this. It can be done somehow.
PhilD41 said:
I can't help you on how to do it, but I know an app that does. Google Maps works this way. It finds my location within about 1Km using GPRS. I don't have GSP on my phone. It only works is some locations. For example, at my house (in a rural area) it doesn't work. I am guessing this is either because I have only one base providing service, or that base is missing certain features.
Good luck on finding a solution to implement this. It can be done somehow.
Click to expand...
Click to collapse
Great, that means that there is actually something called GPRS-positioning, now the 10 billion dollar question is how to implement this
Yes, the Google Maps "location" feature works well for me in USA. It locates the nearest cel towers to my device...good luck with your project.
i don't know about GPRS-positioning, but i do know for sure that Google Maps doesn't use it like PhilD41 said, Google Maps tries to figure out your location using cell phone towers around you. Cell Tower Triangulation, i think is the term. you can search that term and see how to implement it
Azimuth21 said:
i don't know about GPRS-positioning, but i do know for sure that Google Maps doesn't use it like PhilD41 said, Google Maps tries to figure out your location using cell phone towers around you. Cell Tower Triangulation, i think is the term. you can search that term and see how to implement it
Click to expand...
Click to collapse
Oh right then - Been trying to search bit for Cell Tower Triangulation, and found some interesting threads- unfortunatly for me, nonen that describes how to actually triangulate though But so far, I'm very thankfull for all the replies here
here is how it works:
http://www.cim.mcgill.ca/~simra/publications/Thesis/node12.html
and Iphone has already similar software... so if you want to back engineer it: http://technology.slashgeo.org/technology/08/01/03/0440258.shtml
mahsoud said:
here is how it works:
http://www.cim.mcgill.ca/~simra/publications/Thesis/node12.html
and Iphone has already similar software... so if you want to back engineer it: http://technology.slashgeo.org/technology/08/01/03/0440258.shtml
Click to expand...
Click to collapse
Hehe! Now, just to find a way to implement this... Still haven't managed to get any closer to a soultion... :|
Navizon Virtual GPS
Check this out, this program already does what you want:
http://www.navizon.com/navizon_v-gps.asp
It has tracking by gps and virtual gps (gsm bases, wifi)
Hope this helps!
Greetz Bas
neofix said:
I've heard there also are other metods to find out your position, by triangling the GSM-bases
Click to expand...
Click to collapse
I think you're thinking of Assisted GPS. You operator and cell towers' equipement needs to support this for it to work.
rev3nant said:
I think you're thinking of Assisted GPS. You operator and cell towers' equipement needs to support this for it to work.
Click to expand...
Click to collapse
Hi! Thanks for the reply, I belive this is something else then assisted GPS... Since the A-GPS, as you said needs a A-GPS server on the operator-side, while triangulation only needs three cell towers.... (Less accuracy, but still)
bas.bootsveld said:
Check this out, this program already does what you want:
http://www.navizon.com/navizon_v-gps.asp
It has tracking by gps and virtual gps (gsm bases, wifi)
Hope this helps!
Greetz Bas
Click to expand...
Click to collapse
Thanks for the reply!
This is the kind of feature I want to implement, but I need to find out how to do this in coding...
Hi,
some interesting for you i hope.
As far as I can work out GoogleMaps uses the navizon database to triangulate your position. Navizon uses freely donates gps+wifi data.
Here's my slightly informed opinion, from best to worst
connected/Inbuilt GPS: most accurate u will get
Navizon: probably as good as AGPS but i think better as it triangulates on phone mast details and (if u have wifi built in) wifi router details (see website for this cool feature)
A-GPS: next most accurate you will get.
No such thing as SMS/GPRS location. This is in fact a service provided by companies who use a mobile phone operators databases to triangulate your position (API licenses cost between £500 and £2000 in UK PER operator!!!) . So not much better than AGPS but a method (with a cost).
Can you do this in c#? yes. download Visual Studio 2008 90-day trial edition and you'll find a GPS application ready and waiting. Its a bit buggy but a g8 starting point.
If you simply want to get gps position for an app without having to code anything, you might want to wait a little and download my next GPSSpot application. It will save the current GPS position to a registry key for other apps to use.
seanpu1 said:
Hi,
some interesting for you i hope.
As far as I can work out GoogleMaps uses the navizon database to triangulate your position. Navizon uses freely donates gps+wifi data.
Here's my slightly informed opinion, from best to worst
connected/Inbuilt GPS: most accurate u will get
Navizon: probably as good as AGPS but i think better as it triangulates on phone mast details and (if u have wifi built in) wifi router details (see website for this cool feature)
A-GPS: next most accurate you will get.
No such thing as SMS/GPRS location. This is in fact a service provided by companies who use a mobile phone operators databases to triangulate your position (API licenses cost between £500 and £2000 in UK PER operator!!!) . So not much better than AGPS but a method (with a cost).
Can you do this in c#? yes. download Visual Studio 2008 90-day trial edition and you'll find a GPS application ready and waiting. Its a bit buggy but a g8 starting point.
If you simply want to get gps position for an app without having to code anything, you might want to wait a little and download my next GPSSpot application. It will save the current GPS position to a registry key for other apps to use.
Click to expand...
Click to collapse
Wow! Nice reply sir!
But this really starts to stirr around my noodles - since I have a Iphone here, without a GPS, and it can give me a +- 100/200 m accuracy on where I'm using cell tower triangulation...
When it comes to the GPS-part, I've coded it finished, so I'm just so curious on how the author has done it... Is it using some sort of cell-tower location database? Hmm... I've tried to mail the developer, but without luck
But, when it comes to my app, I think NaviZone is the way to go...
if iPhone has wifi (which i believe it does) Navizone is the way forward. It will consume more power as your wifi has to be on. But it will only work in areas that have been "surveyed" by donating users.
(btw its also good to find local free hot-spots/unblocked wifi routers)
btw, cell-tower location databases have a VERY wide range in accuracy. Firstly its dependent on the accuracy of the cell knowing its own GPS position (big discussion came to my mind on how interesting that is, but I'll leave this out for now). Then dependent on the number of cells used in the calculation (the more cells the better.) So, inner city regions get fair to good accuracy, but out in the country accuracy drops to >1000m radius.
I'd be interested to know what the iPhone is like for accuracy out in the sticks, and whether they use NaviZone or a similar service.
The other day the GPS had the weirdest issue. I was stuck in traffic and decided to turn on Google Maps to find out how long the traffic is going to be. To my disbelief, the GPS showed me in a different town and MOVING on the street and then onto some freeway about 50 miles from my location. I thought the GPS satellites are screwed up but my car was showing me in the right place (and never has made such a stupid error).
Makes me wonder if the GPS info is actually going to Google servers and coming back to the phone as I guess I was getting someone else's GPS data and the lines were crossed somehow. This continued to about 30 minutes as I was enjoying the error and wondering at the same time. Holding the phone out of the window and stuff did not work. Eventually I reboot (oops! I meant I took the battery out because HTC apparently thinks we never need to reboot te G1 so there is no PIN hole for reboot like most other phones).
has anyone else experienced the same issue?
brooklynite said:
The other day the GPS had the weirdest issue. I was stuck in traffic and decided to turn on Google Maps to find out how long the traffic is going to be. To my disbelief, the GPS showed me in a different town and MOVING on the street and then onto some freeway about 50 miles from my location. I thought the GPS satellites are screwed up but my car was showing me in the right place (and never has made such a stupid error).
Makes me wonder if the GPS info is actually going to Google servers and coming back to the phone as I guess I was getting someone else's GPS data and the lines were crossed somehow. This continued to about 30 minutes as I was enjoying the error and wondering at the same time. Holding the phone out of the window and stuff did not work. Eventually I reboot (oops! I meant I took the battery out because HTC apparently thinks we never need to reboot te G1 so there is no PIN hole for reboot like most other phones).
has anyone else experienced the same issue?
Click to expand...
Click to collapse
The GPS is not being relayed to google... but google maps may be the thing that is wrong here. You can't get your "lines crossed" when using google maps but the maps may be downloading the wrong set. I know I have seen it do some weird things but that is expected to happen when you have several countries you have to have maps for.
As for the reboot issue... is it really that hard to hold down the power button? You do realize that the pin hole on previous devices is for emergencies only. It could really screw up the phone. Similarly like using your computer and unpluging it while it is on... or just pressing its reset button.
Maybe this is the reason for your problems with your G1.
I was just browsing my location and found that the location was in my local Radio Shack that was 2 blocks away. I tried to refresh but wouldn't allow me to.
G1 uses assisted GPS, which performs some calculations away from your phone. Could have been your A-GPS server was sending back some faulty data.
Some Application in G1 read Location info from Proprietary GPS Chip and also relies on Cell Tower GPS Coordination if GPS Signals is not available, in India my Airtel Company have Bad GPS Coordination in my Cell Tower, I Personally know which Cell Tower i am hooked to while i am at home but the Cell GPS Coordination is 8 Miles away from my Cell Tower.
Check that your GPS Signal were Strong and you have not just started seeing maps when that error occured.
I think it was stong. I had all my bars full and the 3g logo on it. Oh well I'll probably fiddle with it a little more tomorrow after I try to get a screen protector for the phone
I thought the problem had gone away until last night it happened again, with one difference. I still had me being shown 20-30 miles away (interestingly not across the globe but simply 30 miles away) the problem corrected itself after about 5 minutes.
I have a car GPS and a portable GPS and I have never seen this happen before. The issue is definately the A-GPS. I always thought during WAR the military may scramble the GPS data to confuse the enemy, I guess that is what promted Europeans to install their own GPS that is much more accurate than ours.
And there are controversies over this as well. Google is recording my location and my cell towers and IP addresses and URLs according to its NO privacy policy. This is definitely not fun.
Sending my GPS info to Google servers (which is in fact the case) without me knowing it and sending it back to my phone through internet channels it not something I am comfortable with. Especially if Google releases information to law enforcement one day that may be incorrect showing me somewhere I really was not at!
CORRECTION: A-GPS is for phones without GPS. It does not apply to this thread.
brooklynite said:
CORRECTION: A-GPS is for phones without GPS. It does not apply to this thread.
Click to expand...
Click to collapse
Where do you get your information? aGPS is for phones with GPS... it uses a data connection to locate you within so many meters than uses the GPS signal to pinpoint so you are located faster.
brooklynite said:
CORRECTION: A-GPS is for phones without GPS. It does not apply to this thread.
Click to expand...
Click to collapse
Wrong.
http://en.wikipedia.org/wiki/GPS_Phone
http://www.apple.com/iphone/features/gps.html
I have the same dxmn problem with the gps f-ing up. It started with RC30...When I was on RC19...I had NO PROBLEMS with gps.
It would pinpoint my location in 5sec. Now it's take 10-15min to pinpoint me. Google need to fix this fast.
whether it is related to this thread or not...A-GPS....
, generally abbreviated as A-GPS, enhances the startup performance of a GPS satellite-based positioning system. It is used extensively with GPS-capable cellular phones
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Click to collapse
same problem here. i also think it started with the update.
Guys, I am not wrong.
A-GPS as Google calls it (and there are other versions of it), is for phones without a GPS chip (thats how Google Maps find you on a T-Mobile WING), it started after an fcc mandate to be able to locate 911 callers from cell phone. It finds your location using a triangulation of the cell towers you are connected to and this particular technology and the extensive data that is required is owned by Google however Google may not call it AGPS.
http://www.techcrunch.com/2007/11/28/google-mobile-maps-pinpoints-your-location-without-gps/
Now it seems to me that Google is enhancing its data network of cell towers using our phones to collect location data. So it collects the cell towers we are connected to with the strength+ the GPS info from our phones and puts all this data in a server to that non-GPS phones using Google Maps can have a better triangulation as more data is gathered from across the country. Eventually the system could be perfected to locate any cell phone without a GPS chip or to locate a cellphone with the GPS feature turned off for privacy, and that is what concerns me.
When my phone shows me 20 miles from where I am, on the freeway, cruising at 55MPH while I am sitting in traffic on the other side of town, it concerns me.
brooklynite said:
Guys, I am not wrong.
A-GPS as Google calls it (and there are other versions of it), is for phones without a GPS chip (thats how Google Maps find you on a T-Mobile WING), it started after an fcc mandate to be able to locate 911 callers from cell phone. It finds your location using a triangulation of the cell towers you are connected to and this particular technology and the extensive data that is required is owned by Google however Google may not call it AGPS.
http://www.techcrunch.com/2007/11/28/google-mobile-maps-pinpoints-your-location-without-gps/
Now it seems to me that Google is enhancing its data network of cell towers using our phones to collect location data. So it collects the cell towers we are connected to with the strength+ the GPS info from our phones and puts all this data in a server to that non-GPS phones using Google Maps can have a better triangulation as more data is gathered from across the country. Eventually the system could be perfected to locate any cell phone without a GPS chip or to locate a cellphone with the GPS feature turned off for privacy, and that is what concerns me.
When my phone shows me 20 miles from where I am, on the freeway, cruising at 55MPH while I am sitting in traffic on the other side of town, it concerns me.
Click to expand...
Click to collapse
Where are you getting your information? The link you provide just says they support phones without GPS but they never say it is only for phones without GPS. In fact it says that it will work on phones with GPS... that is what the whole article is about that phones in the future will have GPS and google maps will be able to pinpoint their location faster. Basically it says they are using A-GPS.
In the link above he links to http://www.techcrunch.com/2007/11/28/google-earth-heading-towards-extinction/ Which says people will be able to add their own commentary about places like a wiki. Nothing about using other peoples devices to send information for google to collect.
It also has this link http://www.google.com/intl/en/press/annc/20071128_maps_mobile_my_location.html Which is googles official press link saying it will work with both GPS and non-GPS phones by using the Cell ID and a special formula that google developed to pinpoint your location within a certain amount of distance. Nothing says it uses other peoples GPS signals. In fact it says "This approximation is anonymous, as Google does not gather any personally identifiable information or associate any location data with personally identifiable information as part of the My Location feature."
All in all I think you are misreading and need to look over your data again.
neoobs said:
Where are you getting your information? The link you provide just says they support phones without GPS but they never say it is only for phones without GPS. In fact it says that it will work on phones with GPS... that is what the whole article is about that phones in the future will have GPS and google maps will be able to pinpoint their location faster. Basically it says they are using A-GPS.
In the link above he links to http://www.techcrunch.com/2007/11/28/google-earth-heading-towards-extinction/ Which says people will be able to add their own commentary about places like a wiki. Nothing about using other peoples devices to send information for google to collect.
It also has this link http://www.google.com/intl/en/press/annc/20071128_maps_mobile_my_location.html Which is googles official press link saying it will work with both GPS and non-GPS phones by using the Cell ID and a special formula that google developed to pinpoint your location within a certain amount of distance. Nothing says it uses other peoples GPS signals. In fact it says "This approximation is anonymous, as Google does not gather any personally identifiable information or associate any location data with personally identifiable information as part of the My Location feature."
All in all I think you are misreading and need to look over your data again.
Click to expand...
Click to collapse
Regardless of above, and you may be correct and I may be wrong, but the thread is getting distracted from the main subject. My main issue is this: Why is the GPS reporting me in the wrong location, and even MOVING which is weird. It was pretty obvious to me from what I saw that the Google Maps software in my phone was reading someone else's location data from someone else's GPS. I could see the person move through the streets and speed up and slow down. This makes me wonder if my locatio data is being sent to Google servers somewhere and then back to the phone (and in some cases crossed over with another persons data). This feels especially more true because Google MAPS has slowed down dramatically from finding "My Location" compared to "pre RC30" upgrade and even compared to the GPS-Chop-Free WING and even my ancient car's GPS system.
Have you talked to Google about this? I think you are just speculating what you want and have a hidden agenda. Did it locate you within so many feet? or was it a real location? If it was a real location than it couldn't be Google as it only pulls the map the actual lat, long is coming straight from the sats... possibly it pulled the wrong location for that tower while using A-GPS and then this calculated the wrong GPS coordinates.
Since you don't know what or how A-GPS works this may be hard to understand. A-GPS works by using that method you described for non-GPS cellphones to narrow the search for satalites. This doesn't find your location it only finds the vicinity. You can see the A part of A-GPS work when it says your location within so many meters. This is what works on your wing. The actual pinpoint location is based only off the GPS and isn't sent to google. Google only needs the map coordinates to download. Your GPS is what tracks you on the map. This is why google maps always load in blocks.
To fully understand a map system you must learn how maps work and be educated in the art of cairegraphy
I think the real concern is that brooklynite was seeing himself moving through traffic while he was actually stationary. I can understand that perhaps the GPS got the wrong co-ords and the incorrect map was loaded showing him in another location, but you would still expect him to be shown stationary in the wrong location. So why would it show him moving when he was stationary?
The fact that he was moving on the map means the data must have been coming from another device doesn't it? How else could you explain it?
I would be concerned too.
neoobs said:
.... Did it locate you within so many feet? or was it a real location?...
Click to expand...
Click to collapse
A real location about 50 miles away from my location. Somewhere I have never been since I have had this phone so it cannot be using the old data in my phone as sometimes it shows my locations from "last night".
...possibly it pulled the wrong location for that tower while using A-GPS and then this calculated the wrong GPS coordinates...
Click to expand...
Click to collapse
I always have the "use wireless networks" off, afterall, the GPS chip is one of the main reasons I switched to the G1 from my older WING.
....
I have to add that I am amazed by the GPS accuracy, it even notices when I cross the stree, turn into a driveway or the side of the street I am standing on. When I switch to Sat. view, it literally shows my exact spot on the sidewalk, not in the middle of the street like a car GPS does.
Probably getting too far off topic but car GPS units are just as accurate, it's just that most of them have a correction feature to fudge your position onto the nearest road on the map if for some reason it is not. For the most part a driver doesn't care where he is on the road in relation to the curb....only that he is on the road he thinks he should be on.
Hi
Does aGPS require you to have a cellular data connection in order for it to work? Or will it work with any internet connection (eg. using my laptop's connection through wifi)? I'm asking because I don't have a data plan (yet), and my phone has locked only _once_ since I bought it a month or so ago. I've tried switching to MS based in LbsTestmode, changing the supl server to supl-google-com and supl-nokia-com (can't post links yet).
The one time it did lock was when I was testing the GPS without an internet connection, and I entered a WiFi covered area and it suddenly locked (5-10m accuracy). It wasn't WiFi-based positioning because it was my laptop's WiFi hotspot. And I was using the default settings at that time (www-spirent-lcs-com, Standalone mode). Since then I've tried different combinations of settings but it hasn't ever locked.
Another question: What's the difference between MS based and MS assisted modes?
My phone is an I9000 Galaxy S.
ssj4Gogeta1 said:
Hi
Does aGPS require you to have a cellular data connection in order for it to work? Or will it work with any internet connection (eg. using my laptop's connection through wifi)? I'm asking because I don't have a data plan (yet), and my phone has locked only _once_ since I bought it a month or so ago. I've tried switching to MS based in LbsTestmode, changing the supl server to supl-google-com and supl-nokia-com (can't post links yet).
The one time it did lock was when I was testing the GPS without an internet connection, and I entered a WiFi covered area and it suddenly locked (5-10m accuracy). It wasn't WiFi-based positioning because it was my laptop's WiFi hotspot. And I was using the default settings at that time (www-spirent-lcs-com, Standalone mode). Since then I've tried different combinations of settings but it hasn't ever locked.
Another question: What's the difference between MS based and MS assisted modes?
My phone is an I9000 Galaxy S.
Click to expand...
Click to collapse
Correct me if i am wrong, but as i know aGPS doesn´t need any Data Connection to make the triangulation between the GSM Antennas. So no need for Internet Connection to use aGPS.
TMReuffurth said:
Correct me if i am wrong, but as i know aGPS doesn´t need any Data Connection to make the triangulation between the GSM Antennas. So no need for Internet Connection to use aGPS.
Click to expand...
Click to collapse
AFAIK aGPS is different from cellular triangulation. It refers to downloading satellite information from a server for a quicker fix.
ssj4Gogeta1 said:
AFAIK aGPS is different from cellular triangulation. It refers to downloading satellite information from a server for a quicker fix.
Click to expand...
Click to collapse
I thought it would make a triangulation between the next availabe antennas in range and get over a dedicated channel (not data channel as mentioned above) localisation informations. Because my Nokia N80 had aGPS but not real GPS and in the manual they said something about this triangulation.
But of course i know the download of the actual satelite coordenates from my Touch HD in Windows Mobile with a dedicated App. Just thougth it is something diferent.
TMReuffurth said:
I thought it would make a triangulation between the next availabe antennas in range and get over a dedicated channel (not data channel as mentioned above) localisation informations. Because my Nokia N80 had aGPS but not real GPS and in the manual they said something about this triangulation.
But of course i know the download of the actual satelite coordenates from my Touch HD in Windows Mobile with a dedicated App. Just thougth it is something diferent.
Click to expand...
Click to collapse
aGPS is a technology that downloads satellite data from agps servers at realtime (that is the time you are using the GPS): WIKI article
I guess that the app you are refering to, the one you used on the HTC, is Quick GPS. This program doesn't download satellite postition data in realtime but once in a while. (I believe the data are vallid for 48h) With Quick GPS one can still enjoy the features of aGPS while one hasn't a data connection with a aGPS server.
The Galaxy S GPS (BCM4751) seems to have both, aGPS and a sort of Quick GPS. Only the last is called LTO by broadcom. (see: http://www.broadcom.com/press/release.php?id=s443754 about BCM4571 specs and see here about LTO.
aGPS uses cell tower triangulation, and information from a server, in addition to satellite radio signals, to quickly assist in determining the coordinates of a phone's location. Since cell tower sites are precisely surveyed, they are a reliable source for locational data. A data connection is required. All modern cell phones, at least here in the United States, are required to have aGPS service for use in locating a phone by emergency responders. This is a part of the E911 and is required by FCC mandate. Data is used in tracking down the phone, but it happens behind the scenes and is paid for by fees charged to cellular users on their bills for E911 compliance.
On phones that allow the user to make use of the aGPS chip, there will generally be a setting that allows you to set for E911 use only, or for what is commonly referred to as "location based services." On my Android phones, there are actually two settings, both found in Location & Security Settings. One allows for location based upon use of wireless networks, and the other allowing a fix via GPS satellites. Even with any location based services turned off, emergency responders can still find the phone. The difference being that you cannot use it.
While it is technically possible for you to use your phone's aGPS without a data connection, your chances of getting a signal are sketchy, and your chances of getting a really accurate signal are, under most circumstances, slim to none. Much of the computational work in determining your location is done by the assistance server, and guess how that information moves to and from your phone? Yep, you guessed it, data!
GPS signals sent from satellites are simply radio signals, and your local pop music radio station probably sends its signals with more force. As they are radio signals, they have to contend with everything a radio signal has to deal with, and a large percentage of that is man-made. Signals confusingly bounce off of buildings, are weakened by passing through walls and foliage, or can even be absorbed in some cases by different materials.
Some aGPS chips cannot function as stand alone GPS, and will not work at all without a data connection.
Try this, turn off your cellular radio. Make sure that your WiFi is also off. Now, fire up Google Maps and ask it to start navigation. How did it work?
appelflap said:
I guess that the app you are refering to, the one you used on the HTC, is Quick GPS. This program doesn't download satellite postition data in realtime but once in a while. (I believe the data are vallid for 48h) With Quick GPS one can still enjoy the features of aGPS while one hasn't a data connection with a aGPS server.
.
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Click to collapse
Yeah, that i was talking about. Didn´t know this all I love this forum, you always learn more and more.
rasmith3530 said:
Try this, turn off your cellular radio. Make sure that your WiFi is also off. Now, fire up Google Maps and ask it to start navigation. How did it work?
Click to expand...
Click to collapse
Well, using Google Maps would not be a valid test, of course, since you need data connection to download the local map anyway. If you want to test whether data connection is requires by aGPS, you need to use an offline GPS application.
Thank you for your guys replies.
@rasmith3530: So can that data be downloaded over wifi? (My common sense says yes, just trying to confirm.) If it can, then aGPS isn't working for me at all. I see at max 2-3 satellites in LbsTestMode, without a lock on any of them.
No one said aGPS is working on SGS. They are broken and no fixes yet.
foxbat121 said:
No one said aGPS is working on SGS. They are broken and no fixes yet.
Click to expand...
Click to collapse
I think you're right. The fact that there are no ephemeris and almanac data recorded for satellites let me think that it may be the case that with a certain informed guess aGPS and the advertised LTO function doesn't work on none of the firmwares.
Other people seem to have locking/accuracy problems, they can at least see those satellites. Mine normally shows 0 or 1, so I thought maybe I'm doing something wrong.
ssj4Gogeta1 said:
Other people seem to have locking/accuracy problems, they can at least see those satellites. Mine normally shows 0 or 1, so I thought maybe I'm doing something wrong.
Click to expand...
Click to collapse
In JM1-JG5, I had that issue (couldn't lock onto anything). Switching to JM5 fixed that..
****************************************************************
"EDIT" UPDATE (7 oct. 2010)
Well you dont need to go actually much further then this first post!
Things got out of context over here, furthermore I decided to give
my external gps receiver a break and run some more tests with
the internal one of my SGS.
And the results I got were much better than any
other phone I tested before. Except the ones with a build-in SirfstarIII chipset.
If you have Gps issues,Just move on to this thread:
2nd edit (20 Oct, 2010): That thread was removed without any warning or explanation so I posted the videos in another thread:
http://forum.xda-developers.com/showthread.php?p=8903056#post8903056
END EDIT
RCinFLA said:
Like to share my experience as cellphone chipset designer and my dealing with various parties involved with GPS in phones.
Many of the issues are caused by business interests involved and there are quite a few parties plying to control location based services revenue stream.
SUPL, secure user plane protocol AGPS was created by network operators interest in mine, with the objective of putting them in the controlling position when it comes to extracting revenue from location based applications on their network.
Control plane AGPS is a general system where network operator independent entities can create a assist server along with possible services offering. They can encrypt their access to allow only subcribed (paying) users to access their service. The network operators has little control over this scheme.
With SUPL, in most cases, network operators outsource the location server function. Network operator hold location of their cell tower, as a total database, in close confidence. The network tower locations are also very dynamic over time. I believe the AGPS contractors don't get reliable and timely updates from the network operators.
Then there are third party business like 'Skyhook' which is trying to work around the network operator roadblocks by establishing a 'ponzi scheme' server database. If your phone has a good GPS location lock and detects a WiFi network, Skyhook's background app will have your phone send a message to their server reporting the SSID of the WiFi and its location. They then sell their server AGPS service to other companies, like Motorola, for inclusion in their phone software. Motorola may run into conflict with network operators. A network operator might refuse to buy a Motorola phone model with Skyhook installed on it. I noticed from the Captivate forum that the ATT version of Galaxy S has Skyhook capability.
Google is the 900 pound gorilla and is trying to wrestle control of location based services from network operators.
Finally there are the GPS chip manufacturers. Almost all of them have an AGPS server scheme of their own and try to promote it. The frontend processing (up to recovery of raw 50 bps satellite data) has unique hardware and firmware that are considered proprietary by the GPS chip manufacturer. In most cases a phone manufacturers like Samsung or Motorola are not allowed to have the software source code for this firmware or information on the actual interface protocol to the GPS chip. They are given a bundled binary file that the phone manufacturer software just dumps to the GPS chip at startup.
It is now up to the phone manufacturer to implement the GPS chip and antenna systems (along with WiFI, Bluetooth, Near Field Comm, and multi-band cellular) and provide software interfaces and drivers necessary to run the GPS function.
For size and cost reasons most recent GPS chips rely on the main application processor within the phone to actually do the GPS fix calculations. The software for this is provided by the GPS chip supplier but it must be coordinated with the particular applications processor chip used by the phone. It must share processing time slicing with the apps processor and work with operating system software resources such as RAM and ROM management running on the phone.
This is the first obsticle as most of the GPS chip suppliers have little expertise in the OS's that may be used (like Android or Symbian). The phone manufacturer usually has to provide help to create and debug the GPS driver software but the drivers are responsible/owned by the GPS chip supplier. There can be unique hardware/software interfaces that must be dealt with, like providing GPS TCXO calibration and cellular corrected frequency timebase to the GPS chip.
Then there is the OS's GPS interface. There can be translation software layers involved here. One such interface is based on GPS NMEA protocol but with additional hooks for things unique to phone operation like battery saver power strobing, and the complicated Secure User Plane or Control plane interface.
The AGPS system design landscape is litered with intellectual properties (patents) by many parties. Qualcomm is a dominate player here since their aquistion of SnapTrak company years ago. Royalties are paid to Qualcomm for every WCDMA phone sold, not only in AGPS area, but on basic CDMA patents used in a UMTS (Wideband CDMA) phones.
Now as to Samsung Galaxy S implementation of Broadcom GPS.
I think there is a lot of evidence that Samsung had early issues with the GPS antenna contact hardware. This has probably been corrected on recently manufactured phones.
I think the firmware supplied by Broadcom has the bandwidth of the correlators tighted down to provide greater sensitivity. This is great as long as there is a very good AGPS system to provide initial satellite ephemeris data. Without a good AGPS network providing satellite information the initial search and lock can take a very long time with narrow bandwidth frequency bins.
I have not seen evidence with my experience that my two Vibrants are receiving any reliable AGPS information from the T-Mobile network. They do seem to get rough Almanac satellite info from Google or other third party apps. These may be based on WiFi detection more then T-Mobile cell tower locations.
In LBStest I noticed that GPS Operational Mode has been set to 'Standalone'. I interpret this to mean AGPS is deactived. I don't see any difference when I switch to MS based assist, and clear the GPS saved memory to prevent it from prejudicing time to first fix lock test. Switching SUPL server to supl.google.com and port 7276 (with MS based operational setting) just seems to make my phone lockup for short periods of time.
Once phone does get full lock on satellites its performance is quite good. (my two Vibrant's were purchased in early Feb 2011). It rivals my Garmin SiRFstar III based GPS unit in locked on sensitivity while inside a building.
I think the AGPS system issues will get worked out over time.
The Qualcomm based CDMA2000 systems (like Verizon) will likely have better initial coordination on AGPS system operation. CDMA2000 also provides network timebase directly compatible with GPS.
Click to expand...
Click to collapse
*******************************************************************
All this nagging about GPS.....that it is not working in many devices and it's working in other many.....and of course I am talking about those ones who still would go for ONLINE gps navigation.....
In my humble opinion, what you guys should be asking yourselfs and the big corporations is, why nowadays, 99% of the smartphones(so not just sgs), even the most expensive ones are build with weak, less capable internal gps receivers, forcing users to go online(celular network /a-gps) or using external bluetooth gps receivers to get stable satellite fixes that means stable navigation.
Years ago, many of the first smartphones came with sirfstar chipsets or alike , so once again, why not now? That's the question that should not be ignored or forgotten.
A friend of mine, that would not dare to pay more than a 100 box for a phone, bought an ancient ETEN device on a sale for 40 box with that old windows mobile 5 and guess what...the internal gps get fast fixes just like any standalone gps device because it got the same sirfstarIII chipset
Why the heck, the expensive so called high-end smartphones of today are not build with better gps chipsets? Why A-gps? So we are forced to get data accounts?
And what happens when I want to navigate abroad? Roaming?
For data transfer and internet I use wifi; I have it at home and I find hotspots everywhere...I will save those extra 120 euros(or more) per year (data account costs)
And nobody will force me to get one(internet/data account); not even for gps navigation that I so much use..
I use gps navigation only offline, using a external bluetooth device on a daily basis and, many times abroad; it works like a charm on my SGS; and I am talking about serious GPS car navigation software like iGo, Sygic, Navigon etc. .
Don't even use Google maps or alike.
I cannot tell you how my sgs is doing on online navigation, I dont have a data account so I wont even try it.
But once Samsung get this online gps navigation thing fixed, you guys should concentrate your energy on the real issue:
The A-gps scam
And for all the corporations out there: Just deliver a device with a capable gps chipset and you will sell millions..
And for all the users out there: Just get a good compact external bluetooth gps receiver and stop nagging....
Thanks to 3rd party developers, the Android OS on my SGS can be "fooled" and I can connect any navigation software to my bluetooth gps receiver threw programs like Bluetooth Gps Mouse Unlimited and Gps Provider.
I do have to " allow mock locations" at settings first...
« »
¿Ein? You don need data to get GPS fix, A-GPS is only an aid to get faster fixes
I thtink you're a littel misinformed
LOL.. o boy.. the AGPS is to help say if your indoors so you can get a faster lock... the phone will work without it.
Ummm I can see why you would think what you think, but I do believe you are wrong.
Firstly: as far as I'm aware, the SGS has the same GPS chip as the latest TomTom standalone unit.
Secondly: I guess AGPS is a data feature, it uses the triangulation of cell towers and pulls information to assist a sat lock, but it is not really a different way of using GPS. Ultimately you still need to get a sat lock to use a GPS App.
So it may speed up this lock, but it won't replace it. It just means it'll take you a little longer to get a sat lock than without it.
So you have the choice use it or don;t use it, no-one is forcing you to use data.
Logicalstep
Oletros said:
¿Ein? You don need data to get GPS fix, A-GPS is only an aid to get faster fixes
I thtink you're a littel misinformed
Click to expand...
Click to collapse
Lol those online translators dont work that smoothly...
I don't need a data/internet account to use celular networks aid, that means a-gps.That mean going online via 3g or 2g...
But IF I don.t have a data/internet account added to my phone subscription, my phone costs will be much higher depending on my use....
You are missing the point anyway...
betoNL said:
Lol those online translators dont work that smoothly...
I don't need a data/internet account to use celular networks aid, that means a-gps.That mean going online via 3g or 2g...
But IF I don.t have a data/internet account added to my phone subscription, my phone costs will be much higher depending on my use....
You are missing the point anyway...
Click to expand...
Click to collapse
No, you're missing the point, you don't need any kind of data connection to use GPS, you can use it offline
Exactly...already the first line of Wikipedia says it: "Assisted GPS, generally abbreviated as A-GPS, is a system which can improve the startup performance of a GPS satellite-based positioning system."
There is, however, a related issue w/r/t A-GPS and a data account. Back on WinMo, I could download the ephemeris data to speed up the GPS fix for one week in advance (I think it was called QuickGPS or something on my HTC TouchHD, also had sth. like it on an old Eten). This allowed you to get a quick fix for said week, even without a data connection. Android, on the other hand, seems to download this data on the fly - meaning that if you don't have a data account you will experience a slow fix until your almanac has been filled "naturally" by the satellites you're seeing. I experienced that while on vacation this year without a roaming data contract - it took me a good 3-5 minutes to get the first fix and it was good from there on (well, as good as the SGS GPS gets ). I'd love to have some tool that does exactly what QuickGPS did, but I am not aware of anything like it.
TriC_101 said:
LOL.. o boy.. the AGPS is to help say if your indoors so you can get a faster lock... the phone will work without it.
Click to expand...
Click to collapse
I have always smile in my face when someone thinks he can get a lock indoors..
Yes in a cartoon box you can. Not in real building I'm afraid.
And for all those who think SGS's GPS is usable without A.
Try it.
You will see.
Dont post things you just caught on wikipedia.
xan said:
I have always smile in my face when someone thinks he can get a lock indoors..
Yes in a cartoon box you can. Not in real building I'm afraid.
And for all those who think SGS's GPS is usable without A.
Try it.
You will see.
Dont post things you just caught on wikipedia.
Click to expand...
Click to collapse
I can get a lock on 6-7 Sat no problem inside.... and so can lots of others.. don't know what your doing wrong but its not hard to get a lock inside.
Pics or it didnt happen
seems you all are little misinformed as to how the gps on android specifically sgs works. It is actually three systems at work here. Gps standalone without gprs and cell triangulation which gets lock within a minute same as standalone bluetooth units (they also take up to a minute from cold boot but because generally it is plugged in the car lighter and always on people think its blazing fast).then you have agps that downloads preloads data regarding satellite location in regards to your position via network instead of downloading same data directly from satellite thereby saving time. Both these can be used without checking network location in settings so to recap if your network location is unchecked you are still using agps as long as you have network connection (data connection that is).and samsungs system for agps being better than others cause it downloads data for while week as opposed to others downloading data everyone gps is turned on. Third level is network triangulation via cell towers that gets you that instant lock at the cost of accuracy useful mainly to let apps get your general location without having to engage real gps thereby saving power as well as give maps a chance to start calculating route while gps is still getting lock therefore appearing to operate faster.
Idan73 said:
Gps standalone without gprs and cell triangulation which gets lock within a minute same as standalone bluetooth units (they also take up to a minute from cold boot but because generally it is plugged in the car lighter and always on people think its blazing fast)
Click to expand...
Click to collapse
Standalone gps's got their batterys, and thus they start "warm".
Thing is, standalone SRIF3/4 gps gets a warm lock without any AGPS nor network triangulation within 5-10 seconds. SGS (and bunch of top-of-the pack devices) cant come even close to that.
the GPS on the SGS works fine offline
i don't even have data on when going on long road trips
you just need an offline GPS software with maps, like CoPilot or some other one you like
xan said:
Standalone gps's got their batterys, and thus they start "warm".
Thing is, standalone SRIF3/4 gps gets a warm lock without any AGPS nor network triangulation within 5-10 seconds. SGS (and bunch of top-of-the pack devices) cant come even close to that.
Click to expand...
Click to collapse
Sure they do. Sgs warm lock is 5 to 10 seconds as well. To test get the lock first then turn of data and network lock then start gps.restart of the phone same as restart of the standalone counts as a cold boot and takes about minute.
xan said:
Pics or it didnt happen
Click to expand...
Click to collapse
Here ya go.... I don't have to prove anything just look on youtube.. This is the phone on for just 10sec.. if I had waited it would get down to about 10 feet... this pic was taken in a room where I get the lowest signal. and I live in a Condo with 2 foot concrete walls.. I don't have a digital camera.. this was taken with my old Samsung dumb phone.. but it does prove you can get a lock inside no problem.. also if i'm in a house I can get 6-7 sats to lock in the condo 5 at the most in that room.
only 3 sats and maybe the walls are thin
Polarfuchs said:
only 3 sats and maybe the walls are thin
Click to expand...
Click to collapse
LOL Trust me the walls and not thin.. i'm on the 10th floor of a 25 floor Condo complex. I get alot more signal is a house.. Now my X10 can get about 7 Sats locked in the same room. and down to 5 feet. but the point was you can get a lock inside..
I'll try it.
I live in a 3 stories house at ground floor. The shutters are down and I'm 1 meter away from the windows.
After 3 Minutes I get 5 sats in view but none used.
I'll hang on.
Even after 10 Minutes I only have 5 satellites in View and zero in Use.
So no fix for me.
The numbers on top of the bars are from 15 to 25.
Logicalstep said:
Ummm I can see why you would think what you think, but I do believe you are wrong.
Firstly: as far as I'm aware, the SGS has the same GPS chip as the latest TomTom standalone unit.
Click to expand...
Click to collapse
Most of Tomtom devices got a SiRFstarIII™ GPS chipset
If the GS got such one the amount of GPS threads in this Forum would be reduced considerably
What is your awareness based on?
Oletros said:
No, you're missing the point, you don't need any kind of data connection to use GPS, you can use it offline
Click to expand...
Click to collapse
Idan73 said:
seems you all are little misinformed as to how the gps on android specifically sgs works. It is actually three systems at work here. Gps standalone without gprs and cell triangulation which gets lock within a minute same as standalone bluetooth units (they also take up to a minute from cold boot but because generally it is plugged in the car lighter and always on people think its blazing fast).then you have agps that downloads preloads data regarding satellite location in regards to your position via network instead of downloading same data directly from satellite thereby saving time. Both these can be used without checking network location in settings so to recap if your network location is unchecked you are still using agps as long as you have network connection (data connection that is).and samsungs system for agps being better than others cause it downloads data for while week as opposed to others downloading data everyone gps is turned on. Third level is network triangulation via cell towers that gets you that instant lock at the cost of accuracy useful mainly to let apps get your general location without having to engage real gps thereby saving power as well as give maps a chance to start calculating route while gps is still getting lock therefore appearing to operate faster.
Click to expand...
Click to collapse
LOL... Lets put things in perspective :
1) Wich car navigation software do you use
2) when you UNcheck wireless networks =a-gps(in location and security) and you CHECk "use GPS satellites = build-in gps receiver and then you go outside, you start your car navigation software in you gs( taking into consideration that you have the righ map installed) how long does it take to get a fix so you can start driving?
3) Do you know the difference between a cold and warm start? Why the heck some of you mention car lighters????
Please just answer me these 3 questions and meanwhile I will post some educative information