10-05-2014, 10:49 AM
Tracking & Positioning of Mobiles
Tracking & Positioning.ppt (Size: 1.38 MB / Downloads: 12)
What is Base Station?
Wireless computer networking
Each cell is served by a base station (BS)
Base station is a GPS receiver
Each BS is connected to a mobile switching center (MSC) through fixed links
Each MSC is connected to other MSCs and PSTN
NEED FOR MOBILE TRACKING
To facilitate new services to the mobile user. The positioning of the mobile user could provide services like :-
Emergency service for subscriber safety
Cellular Fraud detection.
Intelligent transport system services.
Efficient and effective network performance and management.
EXISTING TECHNOLOGIES & CONSTRAINTS
GLOBAL POSITIONING SYSTEM (GPS)
The mobile telephone is provided with a GPS receiver to calculate its location in latitude and longitude coordinates based on the location information received from a satellite through the GPS receiver.
Increases the price and the size of the mobile telephone.
The load on the mobile telephone is increased.
Power consumption is high.
NETWORK BASED MOBILE POSITIONING
In the case that the mobile telephone network locates the mobile telephone, at least three base stations (BSs) receive a signal from the mobile telephone. calculate the distances between the BSs and the mobile telephone using the arrival time of the signals at the BSs then determine the location of the mobile telephone using the trigonometry.
CONCLUSION
The location of a mobile telephone can be accurately tracked even in the NLOS environment by using more accurate tracking curves connecting the intersection points among circles with the radius being the distances between corresponding BSs and the mobile telephone in a cellular mobile communication system.