The difference between A-GPS and GPS

Today, all smartphones and most tablets are equipped with GPS – a navigation system that can be used, for example, to navigate or determine the location of a device. Not so long ago, A-GPS technology appeared. What is the difference between them?

GPS (from the English Global Positioning System – global positioning system) – satellite navigation system. A-GPS is a special technology that complements the GPS satellite navigation system. What exactly does she give?

The most important thing is an accelerated cold start. When you turn on GPS on your device, the satellite needs to receive information from your device before the current location is determined. This is the so-called cold start, which can take 30 seconds or even several minutes. In the case of A-GPS, the provision of necessary information occurs through alternative communication channels. Such communication channels can be the base stations of telecom operators, but usually the channel is the Internet – mobile or Wi-Fi, depending on which one is currently connected. At the same time, the amount of data transmission over the Internet is very small – often only a few KB.

If you use mobile operator towers, there may be inaccuracies in the positioning of the device.

The second important advantage of A-GPS is an increase in the sensitivity of reception of weak signals in the so-called “dead zones”, which include various tunnels, lowlands, forests with dense deciduous cover, etc..

Disadvantages of A-GPS

Still, you need to understand that along with the advantages, A-GPS technology also has disadvantages..

  • Some A-GPS receivers are combined with a radio module. If the radio module (GSM) is disabled, A-GPS will not be able to start.
  • A-GPS transmits some information over the Internet. You need to understand that for transferring even a small amount of information when roaming, a decent amount can be written off your account.
  • Outside the cellular network and without access to the Internet, the A-GPS accelerated start function will not work.