agps is off

[Guest missing2]

After performing the VZW update on my Omnia my agps always shows right away when i open Google Maps, but it says that i am in Vilnius. Not sure where that is but its on the other side of the world from California which is where i am. GPS still takes a while to get sat locks so if my agps says im in another country the update was pretty useless for me. Does this happen to anybody else? Anybody know how to fix it?

AGPS

GPS

[Guest dmk679]

A few things to things to try:

1 - delete and reinstall google maps

2 - go to options in google maps - try both ways: "managed by windows" and setting com8

[Guest Bulldogs]

I'm not sure how it works, but I notice that anyone who tries to find out their location while in my house (on my wireless network) it tells them that they're at my old address. I don't know if it's just coincidence, but I'm guessing that it's something to do with the ISP information.

[Guest dercetojones]

This happens to me when I'm at work. It says I'm in Vilnius (Lithuania), pretty consistently. Anywhere else, though, its fairly accurate without a GPS lock. I live in St. Louis and work just across the river in Illinois. Its very interesting to me that someone else nowhere near me has the exact same error, though. I just figured something was wrong with the Verizon towers near where I work. Now I blame Google Maps, lol.

[Guest TheDrizzle]

my google maps was working fine, but it started doing this exact thing today, same distant location and everything. very strange, it may have something to do with which tower you hit or something?

EDIT: I drove about 20 miles, then tried it again and it was fine. It must some problem in Gmaps when it gets incorrect data from the towers.

Edited August 1, 2009 by TheDrizzle

[Guest missing2]

This happens to me when I'm at work. It says I'm in Vilnius (Lithuania), pretty consistently. Anywhere else, though, its fairly accurate without a GPS lock. I live in St. Louis and work just across the river in Illinois. Its very interesting to me that someone else nowhere near me has the exact same error, though. I just figured something was wrong with the Verizon towers near where I work. Now I blame Google Maps, lol.

My Omnia is flashed to MetroPCS and i thought that was the problem. But now that i know it happens to people on VZW i guess it must be Gmaps.

EDIT: I drove about 20 miles, then tried it again and it was fine. It must some problem in Gmaps when it gets incorrect data from the towers.

I just wonder how different towers so far away from each other can show the same place in Lithuania.

[Guest X-Ray A4T]

My Omnia is flashed to MetroPCS and i thought that was the problem. But now that i know it happens to people on VZW i guess it must be Gmaps.

I just wonder how different towers so far away from each other can show the same place in Lithuania.

AGPS does NOT use cell towers for positional information. All it does is use the cell towers to download the XTRA data (about 40KB) which contains the latest orbit updates for the GPS satellites. It is the same data you will download from the satellites themselves very slowly before you can get your first lock (which is why you download it via the cell towers) AGPS XTRA data will only help you get a lock sooner, it will not improve your positional data.

[Guest missing2]

AGPS does NOT use cell towers for positional information. All it does is use the cell towers to download the XTRA data (about 40KB) which contains the latest orbit updates for the GPS satellites. It is the same data you will download from the satellites themselves very slowly before you can get your first lock (which is why you download it via the cell towers) AGPS XTRA data will only help you get a lock sooner, it will not improve your positional data.

then how do i see my location even with the location setting turned off? and without using gps in gmaps? im not arguing with you i just wanna know.

[Guest X-Ray A4T]

then how do i see my location even with the location setting turned off? and without using gps in gmaps? im not arguing with you i just wanna know.

My only thought is that the last location is stored. I now that with Garmin XT it shows you at your last location until it gets a fix. It is probable that GMaps is using a seperate location based system as a read somewhere that Firefox was using location aware stuff which is probably based on the IP address of the access points you are using.

But the enhanced GPS stuff used by the GPS itself in the Omnia does not make use of anything other than the GPS satellites for positioning.

[Guest missing2]

My only thought is that the last location is stored. I now that with Garmin XT it shows you at your last location until it gets a fix. It is probable that GMaps is using a seperate location based system as a read somewhere that Firefox was using location aware stuff which is probably based on the IP address of the access points you are using.

But the enhanced GPS stuff used by the GPS itself in the Omnia does not make use of anything other than the GPS satellites for positioning.

Thats what i thought until i seen that for some reason Adryn's CFO3 3.0 rom showed my correct location. With all other roms Gmaps put me in Lithuania. So to test it i flashed to Adryn's 3.0 again, hard reset, without turning location on i open google maps and it showed my location. no satellite locks.

[Guest AngusATAT]

My only thought is that the last location is stored.

I doubt this. I can travel across the state, bring up Google Maps, and have aGPS locate me within 1600 meters. Not extremely accurate, but it knows my general location. Then once GPS kicks in, it'll locate me within 20-30 meters. It definitely pulls some sort of info from the nearby cell towers to get your general position before GPS takes over.

[Guest X-Ray A4T]

I doubt this. I can travel across the state, bring up Google Maps, and have aGPS locate me within 1600 meters. Not extremely accurate, but it knows my general location. Then once GPS kicks in, it'll locate me within 20-30 meters. It definitely pulls some sort of info from the nearby cell towers to get your general position before GPS takes over.

Google Maps uses W3C Geolocation API to determine your location based on Common sources of location information include Global Positioning System (GPS) and location inferred from network signals such as IP address, RFID, WiFi and Bluetooth MAC addresses, and GSM/CDMA cell IDs, as well as user input. You can do the same thing using firefox (http://googlecode.blogspot.com/2009/07/my-location-on-google-maps.html).

[Guest X-Ray A4T]

Google Maps uses W3C Geolocation API to determine your location based on Common sources of location information include Global Positioning System (GPS) and location inferred from network signals such as IP address, RFID, WiFi and Bluetooth MAC addresses, and GSM/CDMA cell IDs, as well as user input. You can do the same thing using firefox (http://googlecode.blogspot.com/2009/07/my-location-on-google-maps.html).

I played a bit with Google Maps on my omnia and on Firefox and Chrome also on http://www.mozilla.com/en-US/firefox/geolocation/ and all give a reasonably accurate location. None use GPS but when I turned on GPS access in Google Maps on the Omnia I had perfect loaction.

[Guest dwallersv]

I'm not sure how it works, but I notice that anyone who tries to find out their location while in my house (on my wireless network) it tells them that they're at my old address. I don't know if it's just coincidence, but I'm guessing that it's something to do with the ISP information.

That's exactly what it is. IP addresses are not particular reliable as location indicators.

speedtest.net thinks I'm in Chicago when I use my Omnia as a WifiRouter and connect my PC. Nevermind that I'm in Scotts Valley, CA.

Just has to do with the Verizon network, how they're assigning IPs, routing, etc.

[Guest dwallersv]

AGPS does NOT use cell towers for positional information. All it does is use the cell towers to download the XTRA data (about 40KB) which contains the latest orbit updates for the GPS satellites. It is the same data you will download from the satellites themselves very slowly before you can get your first lock (which is why you download it via the cell towers) AGPS XTRA data will only help you get a lock sooner, it will not improve your positional data.

You are very wrong. Approximating location from cell tower location data is by definition what "assisted GPS" is.

What you are talking about is GPS ephemeris data. This gets increasing out of date as time goes by and it is not refreshed, and becomes near useless in about 3 days. As you correctly state, this is downloaded directly from the birds themselves, or can be obtained over the internet. And, as you correctly state, the more up to date it is, the faster you will get a lock. This is what is known as a "warm lock".

When aGPS positioning is way off, it is very rarely the fault of the GPS hardware, or the application (in this case, GoogleMaps). It is usually a problem with the positioning data coming from the cellular network. Not all towers provide data, and some are broken now and then.

[Guest dwallersv]

Google Maps uses W3C Geolocation API to determine your location based on Common sources of location information include Global Positioning System (GPS) and location inferred from network signals such as IP address, RFID, WiFi and Bluetooth MAC addresses, and GSM/CDMA cell IDs, as well as user input. You can do the same thing using firefox (http://googlecode.blogspot.com/2009/07/my-location-on-google-maps.html).

Again, true, but this has nothing to do with aGPS.

To an application, an aGPS position looks like a valid GPS location coming from the hardware. There is additional information in the data return that can be examined to determine if it is an aGPS fix or a pure GPS fix, but nonetheless it still is delivered by the GPS chipset (in this case a Qualcomm core).

[Guest X-Ray A4T]

Again, true, but this has nothing to do with aGPS.

To an application, an aGPS position looks like a valid GPS location coming from the hardware. There is additional information in the data return that can be examined to determine if it is an aGPS fix or a pure GPS fix, but nonetheless it still is delivered by the GPS chipset (in this case a Qualcomm core).

When it comes to the Omnia both are actually true:

From Wikipedia:

In certain conditions, Conventional Standalone GPS has difficulty providing reliable positions in poor signal conditions. For example, when surrounded by tall buildings (resulting in multipath), or when the satellite signals are weakened when a GPS device is used indoors or under trees. Some newer receivers are better at handling these situations.

In addition, when first turned on in these conditions, some non-assisted GPS units may not be able to download the almanac and ephemeris information from the GPS satellites, rendering them unable to function until a clear signal can be received continuously for up to 40 seconds.

An A-GPS receiver can address these problems in several ways, using network elements such as either an assistance server or other data from a network. That assistance generally falls into two categories: a) information used to more quickly acquire satellites, or :) calculations done remotely

So the XTRA data IS one form of aGPS and I am pretty sure that this is the only method that the Omnia GPS chip uses for aGPS as if you have downloaded the XTRA data you will get a lock with no 3G activity. Software like Google maps use the other form of aGPS which has nothing to do with "GPS" but uses the network data and IPs to send to the server that calculates the approximate location and returns it to the device. Google Maps can also make use of GPS hardware if you have it for an accurate fix. Certain agps chipsets might make use of network data.

It is just that most people get confused by the XTRA data form of aGPS and think that they are going to be constantly downloading data from the cell towers, often at high data rates, to keep a fix where as it is just a small download once a week.