Related
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.
Hey guys, can someone confirm that when using the GPS function it does or does not use data plan? I know some phones such as the iPhone and Blackberry uses data for GPS, and I know the Touch HD is not required as it has the GPS receiver in the device. If someone can confirm this that would be appreciated.
Thanks
Hi!
No the phone has built in GPS Receiver
Awesome, I'm glad that they don't use data for the GPS function, that would be such a killer on data. Thanks for clarifying.
A GPS by definition must not use data. There are other methods of determining location besides GPS, but they are definitely not called GPS. Note that your device, though equipped with a GPS can ALSO use the cell network for finding its location.
So in the case of the iPhone 3g, what would you call that? My dad uses his "GPS" quite a bit but of course uses the data to download the maps. I'm assuming that the HTC Magic has the maps downloaded on the phone already therefore not needing data. Also when the cellphone uses the cell network to triangulate your position, that is not using data correct? I appreciate all the responses and clarification.
Thanks!
I have no knowledge or interest in apple junk.
However, you seem to be confusing the GPS with *what you do with* the data from the GPS. In your example, to me it sounds like it probably has a normal GPS that does NOT use data. GPS does NOT provide maps, pictures, or anything of the sort. GPS provides locational information by comparing the signals from several satellites to generate information like latitude, longitude, altitude, and bearing. This is all a bunch of numbers that the typical user won't be able to make much use of, so along with the GPS itself, you have some program that *does something* with the data. If you use google maps, then your phone will pull appropriate information from google's servers based on the information retrieved from the GPS. Another program that you could use, for example, is "gps status" (available on the market, use "gps status 2" for android 1.5 equipped devices), this will display the GPS information (and accelerometer) withOUT the maps/pictures/etc., and thus will NOT use any data from your data plan.
Regarding the cell tower location method... it doesn't use any data plan data, however, that does not mean that it is free.... check with your provider for specifics. Generally, cell tower location is crude whereas GPS is fine.
Does that help to clarify things?
Yes it does, thanks for your reply.
Other questions... CAn I use GPS software without Internet connection? Or I need all time internet to magic downlaod maps and info? It is any program Tomtom style for android? Thanks.
if someone has, or does release an application that contains its own map tiles, it will be entirely free to use, but will probably cost a fair amount to buy (the map tiles don't come cheap to the developers). Also I would expect such an app to be fairly large, and (if it does even fit) would eat up most or all of the 512 MB you can store your software in.
thinking about it, they could always give you an sd card with the maps and only have a fairly small app in the phone memory. although that's another matter
As long as an app uses google maps (or other online map resources), it will cost you data to use it.
****************************************************************
"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
Does both Rogers and AT&T Samsung Focus have a built in GPS (don't need a data plan)? Ever site I've looked at for the specs gives conflicting information.
fastmhc said:
Does both Rogers and AT&T Samsung Focus have a built in GPS (don't need a data plan)? Ever site I've looked at for the specs gives conflicting information.
Click to expand...
Click to collapse
As I understand, my focus at&t has built in GPS that can be used with and without a data plan. It just depends what GPS software you are using for instance any GPS software that uses realtime updates or online maps requires data to be used while GPS is enabled...some 3rd party software use stored on device offline maps that would not require a data plan. As for specific programs that use online and offline maps I don't know. I use a data plan so I don't have to worry about that stuff.
This is my understanding so if anyone has better insight be my guest
All WP7 phones have a GPS, just like they all have a camera, three front buttons, a gravity sensor, proximity sensor, ambient light sensor and a compass. There are free GPS apps that are on the Marketplace that will allow you to see the GPS does work.
In time, there will be standalone gps navigation apps for sale on the Marketplace, it just takes a little patience.
I just don't want assisted GPS (A-GPS). I want an integrated GPS chip. All phones dont' have a built in GPS (I think older iphones). I currently have a Samsung i8910 and it has an integrated GPS. I bought Garmin software to use the GPS maps and when I am overseas I just need to buy the maps for that region to access the maps. If you have A-GPS you have to buy a data plan from that country's carrier and using their network, you access the internet (google maps) to get your maps. I hope that is clear??
You totally misunderstood what A-GPS is.
Sent from my SAMSUNG-SGH-I897 using XDA App
Maybe I don't? this is a quote for the wiki page for GPS navigation for phones
" Some phones with GPS capability work by assisted GPS (A-GPS) only, and do not function when out of range of their carrier's cell towers. "
WP7's have A-GPS. They use both radio towers and satellites to obtain a fix on your location.
So yes, once a proper mapping application is released, you can travel to other countries without needing a data plan.
From wiki, sums it up pretty well i would say:
""Standalone" or "Autonomous" GPS operation use radio signals from satellites alone. A-GPS additionally uses network resources to locate and utilize the satellites faster as well as better in poor signal conditions."
Source:
http://en.wikipedia.org/wiki/Assisted_GPS
fastmhc said:
Maybe I don't? this is a quote for the wiki page for GPS navigation for phones
" Some phones with GPS capability work by assisted GPS (A-GPS) only, and do not function when out of range of their carrier's cell towers. "
Click to expand...
Click to collapse
Most of today's cell phone GPS chips can work either in standalone mode or Assited mode. A(ssited)-GPS helps to speed up your initial satellite lock by downloading satellite information from network. If you have no data connection, the chip will fall back to standalone mode. With A-GPS properly working, you can achive first lock within 10 seconds. Without it, you may have to wait for couple minutes for your first lock. After the initial lock these GPS chips work autonomously unless you use MS-Assited A-GPS mode. With the power of today's Smartphone, there is zero reason for using MS-Assisted mode unless you're using it in E911 situations.
It is ultimately the navigation software you choose determines whether or not you need cell data connection. Currently standalone navigation software on WP7 is quite limited or non-existent. If that is important to you, you may want to look for other Smartphones like iPhone or Android phones. Your old WM software won't work in WP7.
I wonder if it is possible to use my GPS without my mobile connection. I like to use GPS in the airplane with an offline navigation.
Whenever I turn off my mobile connection of my HTC DESIRE, the GPS gets lost too . Is there a way?
What application are you using for your GPS? Most apps pull the actual maps from the internet and don't store them internally which might be the reason you can't use your GPS when your network is off. I guess if you could find an app that has the reference to the maps locally and install the maps locally (about 1GB for the US) then you shouldn't have a problem.
http://androidcommunity.com/forums/f12/offline-gps-maps-20226/
Some discussion on the thread above regarding your topic. Many people have posted about it. Not sure what's out there.
it's first bcoz it can't download the maps from the net.
But even without this, if you're using GPS Essentials or GPSTest for example -apps which only display the GPS stats- you'll notice it doesn't work either. And this is because the chips in s-phones are A-GPS chips, which need an internet connection to download precalculated data about satellites approx. positions, almanach data, etc etc. This helps the chip in getting a GPS lock faster, but makes it internet-dependant (the data is valid for 6 days, provided you don't change location by more than 50 miles or so. But usually the device tries to download fresh data each time the GPS is 'cold-started' -first start after a reboot or some prolonged inactivity period- and falls back to the old data if there's no connection. Past 6 days, the data is flagged as 'deprecated' and isn't used anymore whatever the case may be)..
At first only a handful of smartphone makers implemented those chips because they're cheaper to produce and take less space (most of the calculations for determining the user's position is done by the CPU, the A-GPS chip mostly only collects the data, filters it and forwards it), but then some american government agency (can't remember if it was the one regulating automotive transportation or some other though) made it mandatory for all devices sold in the US, to help paramedics and other rescue services in locating injured car-drivers quicker and more efficiently (the theory behind being that an A-GPS chip equipped device demands less interaction from the user to start up the GPS function and get an accurate fix on the position. An A-GPS chip is *supposed* to be able to get a lock and fix all by itself once the GPS is started, so that'd be only a movement of the thumb for the injured person to launch a distress call -provided he/she is able to grab the phone, of course...). But they were a bit shortsighted -as usual, if I may say- in that if the driver 'choses' to crash in a remote location where there's no 2G/3G/4G carrier coverage, he's pretty much screwed anyways, unless he resorts to the good old voice-comm'..
And of course since the US is one of the main phone markets in the world, the same phones are winding up all over the world by now.
thanks for all replies.
it actually worked well in FLIGHT MODE. I used to pre-cache some maps which is possible since the new google maps update.
worked like charm
yea but this is because you got a HTC phone.. They're typically embarking better A-GPS chips than the norm (Qualcomm-made, for the most part).
They're better than the SirfStarIV I have in my SGS2 for example, not by their precision (which is roughly the same and even a bit superior for the SirfStarIv) but by their lock-on times and the quality of their reception (which relies a lot on the built-in antenna which seems to be better by HTC).
With my HTC Desire "S" I was often able to get a lock-on even within a building (=with no clear overview of the sky), just by standing near a window... With the Galaxy S2 I have to extend my arm as far out the window as I can to be able to lock a puny 4-5 sats... :/