The direct physical path between the mobile terminal and the antennae of the Base Station.
Published in Chapter:
Mobile Positioning Technology
Nikos Deligiannis (University of Patras, Greece), Spiros Louvros (Technological Educational Institute of Messologgi, Greece), and Stavros Kotsopoulos (University of Patras, Greece)
Copyright: © 2009
|Pages: 9
DOI: 10.4018/978-1-60566-026-4.ch414
Abstract
A radio mobile-position system operates by measuring, processing, and storing physical quantities related to radio signals travelling between a mobile terminal and a set of transceivers, for example, satellites or Base Stations (BSs). Positioning techniques in cellular networks are of great importance for supporting emerging services that require a sufficient, precise estimation of the position of the mobile terminal (MT) associated with a number of given base stations. The ability to support position location within wireless networks provides network operators with valuable services, as well as users with a host of new applications. This includes navigation, location-based services, network management, and security applications. Nowadays in GSM networks, there is no specific algorithm included in the software to locate subscribers. The only possibility to locate a subscriber is accomplished by using GPS technology or special firmware. An innovative development should be the design and implementation of certain location positioning techniques, as Time of Arrival (ToA) and Angle of Arrival (AoA), over the existing GSM network. Although there are already next generation networks in use nowadays (UMTS, GPRS, WLAN), and there also is extensive research towards the fourth generation cellular networks, GSM seems to be the most popular network so far. GPRS network is a data network over GSM platform and it exists only with GSM architecture. The reason is that GPRS uses the GSM air interface (Radio Network Part) and it only diverts in the core network where it transmits the data packets towards a different switch. UMTS, on the other hand, is a unique network supporting cellular and voice-data applications, and is the evolution of GSM towards IP applications. Although it could be implemented separately from GSM, most of the operators preferred to implement it in a GSM convergence mode towards the core network for eliminating the investment. As a result, in most countries GSM is the major network with full geographical coverage and network location positioning techniques are most implemented in a network environment with a satisfactory number of Base Stations.