[pkaravites]

This might be a stupid question but, does the 8820 GPS work off a satellite or cell tower to the satellite? Second question would be if your phone is out of range of a signal does the GPS still work? Thanks

[CanuckBB]

GPS coordinates are off the satellites. Maps display require a data connection.

[JRSCCivic98]

Autonomous GPS (build in GPS chipset in the 88xx RIMs) is satellite. aGPS (assisted GPS) is cell tower triangulation. ALL RIM devices that have built in GPS are full autonomous and satellite based. That is unless you're with Verizon which likes to disable the chipset and charge you to use their aGPS system.

[krylon..]

Originally Posted by JRSCCivic98

Autonomous GPS (build in GPS chipset in the 88xx RIMs) is satellite. aGPS (assisted GPS) is cell tower triangulation. ALL RIM devices that have built in GPS are full autonomous and satellite based. That is unless you're with Verizon which likes to disable the chipset and charge you to use their aGPS system.

So does this mean you can use a BB device such as an 8310 like a regular GPS even if you have no cell signal? (if using a program like BB Tracker)

[CanuckBB]

Originally Posted by krylon..

So does this mean you can use a BB device such as an 8310 like a regular GPS even if you have no cell signal? (if using a program like BB Tracker)

With no cell signal, the 8310 will still be able to give lat/long.

[Spamdumpster]

Originally Posted by krylon..

So does this mean you can use a BB device such as an 8310 like a regular GPS even if you have no cell signal? (if using a program like BB Tracker)

As canuckBB pointed out, the answer to your question is yes. Also, some mapping problems (e.g., mapquest navigator) download all map data when you route your trip. So, as long as you stay within a small corridor of your route, these programs will still show you the map even when you're out of cell range.

[krylon..]

Basically the same functions as say an normal/non-mapping GPS handheld...??..

Sweet..... Thanks guys, that is great news!!!

[takeshi]

A lot depends on the app you decide to use.

[rygonet]

I just emailed Telenav to see if they allow you to pre-download maps for a given region. Hopefully the answer is "yes" and you are able to save it to your media card.

[cg59]

Originally Posted by JRSCCivic98

Autonomous GPS (build in GPS chipset in the 88xx RIMs) is satellite. aGPS (assisted GPS) is cell tower triangulation. ALL RIM devices that have built in GPS are full autonomous and satellite based. That is unless you're with Verizon which likes to disable the chipset and charge you to use their aGPS system.

How do I know if my 8703e has an Autonomous GPS or just aGPS?

[jltx114]

Originally Posted by cg59

How do I know if my 8703e has an Autonomous GPS or just aGPS?

download google maps at Google Maps and see if it shows your exact location.

[cg59]

I tried what you said but only get the approx location using the triangulation method.

[Mark Rejhon]

Originally Posted by JRSCCivic98

aGPS (assisted GPS) is cell tower triangulation.

Wrong. Not correct.

AGPS IS NOT ANTENNA TRIANGULATION...
The "a" in A-GPS is Assisted, not Antenna.

aGPS is satellite based, but downloads the ephemeris (locations of satellites) over the cellular network. Some cheapie GPS chipsets don't know how to calculate the locations of satellite, and need 'help' by downloading the data OTA in order to find the satellites, which are then finally used to pinpoint the location. That's why Verizon charges you. This is different from triangulation.

The antenna can provide other help, such as speed up the calculation of the location of satellites based on the location of the antennas. No location triangulation is being done with the antennas, the location triangulating is being done with the signals from the satellites themselves. The cell tower antennas are just helping with locating the satellites. (And, sigh, a big excuse for Verizon to charge for the service.)

Too many people confuse GPS, aGPS, and antenna-based location triangulation. These are three separate things. Even the customer service at many cellphone companies confuse the three, thinking there are only two.

Both GPS and AGPS can be equally accurate, good enough for TeleNav, etc.
Verizon's AGPS can still be very accurate, good enough for TeleNav, etc.
Antenna triangulation is not very accurate (can be 1km off), it's never used for map navigation software.

Wikipedia:
GPS (Rogers, T-Mobile)
Assisted GPS (A-GPS) (Verizon)
Verizon VZ Navigator
Ephemeris (All GPS chips need this)

Makes better sense?

[Mark Rejhon]

Originally Posted by jltx114

download google maps at Google Maps and see if it shows your exact location.

Both Autonomous GPS and aGPS are capable of doing exact location good enough to locate you on a specific road.

It's only antenna triangulation (not the same thing as aGPS) that will only give you an approximate location, typically not good enough to locate you on the exact road you are on.

In general, if you have GPS in a GSM-based device, it's generally autonomous. You got an 8310, so it'll be autonomous, although most software requires map to download over the air. (at least until the companies decide to allow you to buy predownloaded maps to put on your memory card.)

[jibi]

Originally Posted by Mark Rejhon

Antenna triangulation is not very accurate (can be 1km off), it's never used for map navigation software.

Google Mobile Maps uses antenna triangulation for non-GPS devices.

[jltx114]

Originally Posted by cg59

I tried what you said but only get the approx location using the triangulation method.

then you dont have true gps. just cell tower based positioning

[CanuckBB]

Originally Posted by cg59

How do I know if my 8703e has an Autonomous GPS or just aGPS?

8703 would be tower triangulation unless you use a puck.

AFAIK, only the 88xx and 8310 have built in GPS receiver.

[saua]

Originally Posted by CanuckBB

8703 would be tower triangulation unless you use a puck.

AFAIK, only the 88xx and 8310 have built in GPS receiver.

That's not exactly true. There are quite a few Models that include GPS, even in the older range:

Livelink - Redirection

[Iare Tosevite]

So which of those 3 do 8830 have? I think it's aGPS because it doesn't work without network connection.

[CBR900RR]

FYI, my tmobile 8800 GPS works without any data connection.