In the last decade, location and tracking of a mobile terminal (MT) in wireless communication networks has attracted a lot of attention. Historically, the need for pinpointing a mobile user arises as a matter of security, in order to track emergency calls made trough the US Enhanced 911 (E-911) service. Nevertheless, there are many other applications that make positioning techniques attractive for wireless service providers, such as mobile yellow pages, ''where I am'' applications, navigation services, location-sensitive billing, restaurant/hotel finders, mobile gaming, and so forth. Moreover, position location systems enhance public interest services, such as fleet management, roadside assistance, traffic routing and real-time vehicle scheduling. Real-time position location can also be used to track service personnel (e.g., police officers, rescue teams, fire brigades, etc.), lost children, suspected criminals and stolen vehicles. Finally, subscriber location positioning allows service providers to improve network design and yields resource optimization. For instance, spectral efficiency can be improved and a more effective radio resource management (RRM) can be obtained through channel allocation based on actual mobile user location. Among the many location systems proposed in the literature, the most effective are those based on radiolocation techniques that exploit measurements of physical quantities related to radio signals travelling between the MT and a given set of transceivers whose location is known, e.g. base stations (BSs) and/or navigation satellites. Radio signal measurements are typically the received signal strength (RSS), the angle of arrival (AOA), the time of arrival (TOA), and the time difference of arrival (TDOA). More recently, radio location algorithms based on a combination of the above location-related measurements have also been proposed. Such hybrid techniques guarantee a high-accuracy location, which is more and more required by value-added location-based services, as for example security applications and mobile gaming.
|Autori:||M. PORRETTA; NEPA P; G. MANARA; F. GIANNETTI|
|Titolo:||Location, Location, Location|
|Anno del prodotto:||2008|
|Digital Object Identifier (DOI):||10.1109/MVT.2008.923969|
|Appare nelle tipologie:||1.1 Articolo in rivista|