Location-based services need a human touch
A question that most parents with teenage children often ask is “where are you?”. To help to answer this question, wireless service providers begin to offer location-based services that allow parents to monitor the whereabouts of their children on home computers.
To determine the location of a cellphone user, a service makes use of wireless signals from the cellphone. Based on the cellphone’ signal strength, the service is able to compute the relative position of the user from a group of cell towers. Knowing the geographical location of the user’s cellphone (i.e., a latitude/longitude value pair), the service then perform “reverse geocoding” to determine the location of the user.
In theory, the service works. In practice, however, there is a problem that was quite unexpected. Here is the problem:
Read the rest of this entry »