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androidpositioning

mobile positioning in google maps using only internet

I used an android smartphone in the following situation:

  • without SIM-Card
  • connected to a WLAN
  • located in an indoor environment (GPS does not work)
  • located somewhere other than the address probabely set in google account

for positioning in Google-Maps App. The result was roughly correct (about 15 meters error).

  • There is no GPS signals to get position.
  • Thre is no SIM-Card. So using Cell ID is impossible.

It means the only resource from which my position is achieved is internet. Could anybody explain to me (while I couldn't find anything in internet) how this is possible?

Solution

  • Google gathers information on the SSID of WiFi hotspots. They drive around with cars gathering street views for their maps and other information like the location of WiFi hotspotes. They store it in a data base somewhere and when you ask for your location it will find out the SSIDs of every WiFi hotspote around you and then give a rough estimate based on signal strength and other information.

    Google might use people's cell phones to gather WiFi SSID information as well I am not really sure about that though. I think this because there are setting in most android phones asking to help Google for accuracy using WiFi...

    Other sites use public ISP information obtained by IP address but this is not as reliable as it gives the location of your ISP (Internet Service Provider).

    Here is a site where many people are discussing this topic.

    Here is a site that teaches how Google finds location data through SSID

    Here is a site that teaches how geolocation software finds ISP location