Jargon buster (1.1) positioning methods

This is the first part of this series. It includes jargon terms relating to the positioning methods that are provided on our mobile devices..

Gps - GPS is the short form for Global Positioning System and it is used to locate one's position on the earth. It communicates with satellites to calculate your position in terms of latitude, longitude and altitude. Combine this data with a map and you know where you are standing. Mapping softwares use this technique to support all other associated features like navigation, geotagging, real time traffic updates, friend finder and more. Most mid range phones these days come with inbuilt gps recievers and usually have mapping software preloaded on them. On a nokia phone you would get ovi maps, on an android phone you get google maps and so on..



Global positioning system is actually an array of 27 satellites orbitting the earth. All of these satellites were launched by the U.S. army and were used by them for their military navigation system. When they opened it up for the public, standalone consumer GPS devices made it to the markets and slowly the technology crept into the mobile world.So manufacturers started embedding GPS modules onto their phones to make it another USP for their product. Nokia even launched an exclusive range of navigator phones. Now, however this feature has become pretty much a very standard feature for phones priced at around Rs.8000 or more.

I would have loved to write about how this system works but, that seems irrelevant here. But, If you are curious follow this link http://www.pocketgpsworld.com/howgpsworks.php or this link http://electronics.howstuffworks.com/gadgets/travel/gps.htm or google for it.


A-GPS - AGPS stands for assisted gps which is basically an addition to a gps module using which the device can lock on to satellites a little faster and also improve the accuracy of the module. An average gps module without agps would take around 8 to 10 minutes to lock onto the satellites(known as TTFF-Time To First Fix). This timing can be reduced through the use of agps. So, it always is an advantage to have agps with standard gps on your phones. Now a days however, if your phone has got gps then 90% chances are that it will have agps too.

An agps system can work in different ways but, a basic working fundamental is that it communicates with an assistance server via the internet. The assistance server returns information related to agps which is then used by the gps module for a faster and more accurate fix of its position. An agps server can supply a wide range of information to be used by the gps module.