Using the GPS Features of Your Cell Phone?

travik asks: "I use a Nokia 3650. The cell phone already knows my co-ordinates (E911 service). It has Bluetooth. Why can't I send the coordinates using Bluetooth to my laptop, and use a mapping application to give me my location and directions to where i want to go. I've searched Google and also read up on old posts, no one seems to be doing it. Why?"

Comments

Positioning Techniques

[neglige]

The cell phone already knows my co-ordinates (E911 service).

Careful not to mix up different positioning techniques :) Your cell phones does _not_ know its position. The _base station_ of the network does. This is assuming that you are _not_ using GPS, but let the network find out the position of the device by

• using the cell ID of your current radio cell - precision varies with cell size (100m to several km)
• using the 'angle of arrival' (AoA) of the radio waves to and from your mobile device
• triangulate the device with 'Enhanced Observed Time Difference' (E-OTD), requires additional base stations in rage

These are just a few, there are several more.

GPS, on the other hand, requires you to have a GPS receiver. If you have one, your device can determine its position. You do not require a mobile phone network for this, but you need at least 3 GPS satellites "in view" (meaning: you must see the sky, GPS won't work within buildings; there is "indoor GPS", but this is about creating 'artificial satellites' within a building).

GPS gives YOU your position, and YOU alone, unless you transmit the information (e.g. to a map service). The techniques described above give your position to the network operator, not you. The operator then has to give the information to you or some mobile service. With E911, in case of an emergency the network operator reports your position to the emergency units.

Why can't I send the coordinates using Bluetooth to my laptop, and use a mapping application to give me my location and directions to where i want to go.

As said above, if you do not have a GPS receiver, YOU do not have your position. You have to use whatever service your provider offers (if any). To use the laptop you need a GPS receiver. Connect that to the laptop, install the right software... and voila :)

Hope that helps ;) There are tons of information on this subject. If you'd like to have more details, I'll point you to some papers on that matter.

Solution right there:

[AdamInParadise]

WayFinder.

Basically, it provides you with a simple GPS module that communicates with your mobile through Bluetooth. Map and directions are provided by an online service and appear on the screen of your mobile. Neat!