Let’s say you want to show off how your phone functions as a GPS receiver to your friends and show you where you are right now on a map; problem is, you will need to be outdoors to get a precise positioning of yourself and chances are you will receive a “No GPS” message if you are not. To solve this problem (not the show offing!) a standard in the positioning world called A-GPS has been created.

A-GPS stands for assisted GPS. The assistance, in this case, comes from MTC or Alfa’s or any other network provider's antenna towers! Needless to say, you will need to have proper reception (which is not always the case here in Lebanon) and an active Internet connection.

The way A-GPS works is that while your phone’s GPS chip is trying to hook onto four of the thirty one satellites of the GPS constellation (three satellites are enough to get your longitude and latitude, but a fourth is needed to detect altitude), your phone can attempt to detect a preliminary position via A-GPS. To do so, your phone, using its data connection, will triangulate its position from the GPS data of the antennas it is connected to. These antennas are actively pulling their own location information, so while the phone’s GPS receiver is connecting to the satellites far in space, the antennas of MTC or Alfa will be feeding it with a rough location estimate. Your phone gets positioning information from three antennas and approximates its location within the range of the three.

If you decide to take your friend out to the balcony outside to get a better fix on your location, the range in which you could be located will diminish as your position accuracy will increase, seeing that your phone will be capable of connecting to actual GPS satellites. But seeing that it usually takes at least 90 seconds to around three minutes to connect to enough satellites, A-GPS would cut the time needed for an approximate position by providing location information within around 15 seconds.

The benefits, thus, of using A-GPS include, a faster location fix (albeit much less accurate), the ability to get a location indoors or when surrounded by high buildings, not to mention saving some battery power.

Most Nokias support AGPS and its configuration is quite simple. In your applications folder, under "Location\Positioning\Positioning Methods", you will find Assisted GPS. Make sure this option is checked in order to enhance your GPS experience and make your location experience better. A-GPS assists you, so to speak, in getting an approximate location range with applications such as Google Maps and of course Ovi Maps.

Hope your friend was impressed.