2195591 is referenced by 1 patents.

A method and apparatus for determining the location of a mobile telephone within the serving area of a mobile telephone system are disclosed. A mobile switching cent er analyzes the calling mobile telephone number and called telephone number to determine if a location function is required. Upon initiation of the location function by the mobile swi tching center, a mobile location module calculates a location estimate of the mobile telephone. The mobile location module receives a list of signal strengths received by the mobile telep hone from cell site antennas within the serving area. The distance between the mobile telephone and a plurality of cell site antennas is calculated using a technique which reduces th e error component of the calculated distances. These reduced error distances are used to geometrically determine an estimate of the location area. In addition, the mobil e telephone comprises a GPS receiver/processor for sending the most recent GPS coordinates o f the mobile telephone which are within a predetermined confidence level to the mobile location module. These GPS coordinates are compared with the calculated location area to increase the accuracy of the location determination.

Methode et appareil pour determiner lemplacement dun telephone mobile
Method and apparatus for determining the location of a mobile telephone
Publication Number
Application Date
January 21, 1997
Publication Date
September 4, 2001
Macdonald Alan Denis
Kauser Nicolas
At&T Mobility Ii
At&T Wireless Services
G01S 05/14
G01S 03/02
H04Q 07/34
View Original Source