Positioning (telecommunications)

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Mobile positioning, i.e. location based service that discloses the actual coordinates of a mobile phone bearer, is a technology used by telecommunication companies to approximate where a mobile phone, and thereby also its user, temporarily resides. More properly segregated the term applies more to a locating process rather than a positioning process. Such service is offered as an option of the class of location-based services (LBS)[1].

The technology is based on measuring power levels and antenna patterns and uses the concept that a mobile phone always communicates wirelessly with one of the closest base stations, so if you know which base station the phone communicates with, you know that the phone is close to the respective base station.

Advanced systems determine the sector in which the mobile phone resides and roughly estimate also the distance to the base station. Further approximation can be done by interpolating signals between neighbouring base stations. Qualified services can obtain a precision of down to 50 meters in urban areas where mobile traffic and density of base stations is sufficiently high. Rural and desolate areas may see miles between base stations and therefore determine locations less precisely.

Privacy

Locating or positioning touches upon delicate privacy issues, since it enable someone to check where a person is without the person's consent. Strict ethics and security measures are strongly recommended for services that employ positioning, and the user must give an informed, explicit consent to a service provider before the service provider can compute positioning data from the user's mobile phone.

Officially, the authorities (like the police) can obtain permission to position phones in emergency cases where people (including criminals) are missing.

In Europe, where most countries have a constitutional guarantee on the secrecy of correspondence, location data obtained from mobile phone networks is usually given the same protection as the communication itself. The United States however has no explicit constitutional guarantee on the privacy of telecommunications, so use of location data is limited by law.

With tolling systems, as in Germany, the locating of vehicles is equally sensitive to the constitutional guarantee on the secrecy of correspondence and thus any further use of tolling information beyond deducting the road fee is prohibited. That leads to the strange situation that even obviously criminal intent may not be interfered by such yet available technical means.

Alternatives

GPS units, though more costly than a mobile phone, are tailor-made for the purpose of positioning, and provides commercial handsets with a precision of down to 5 meters in the USA.

References

See also