Cellular network-based location system

Abstract

In a cellular system configuration, the location of a mobile station is determined from the acquisition of cellular network data pertaining to the mobile station, and the translation of such network data into a corresponding geographical position profile. The cellular system includes a mobile station locator entity for receiving from a mobile switching center the network data such as cell and/or sector ID and trunk group member number. The mobile station locator translates the network data into position information such as geographic coordinates (latitude and longitude), resolution (radius), and angle values for sectorized cells.

What is claimed is: 
     
       1. In a cellular system comprising a plurality of cell sites each including a plurality of mobile stations in communication with a base station, and comprising a plurality of interconnected mobile switching centers each in communication with the base stations of certain cell sites, wherein each mobile switching center maintains network identification data for each mobile station being served in said certain cell sites, a method of determining the location of a mobile station originating communications within a cell site, comprising the steps of:
 acquiring the network identification data for said mobile station from the mobile switching center serving said cell site; and   translating said acquired network identification data into geographical location information using indexable tables generated from data of trunk groups and member numbers used by each cell site and data front geographic maps of radio coverage for said cell sites.   
     
     
       2. The method as recited in  claim 1  wherein the acquiring step includes the steps of:
 transmitting from the mobile switching center a cellular channel including an identity code assigned to the communicating mobile station; 
 prompting the mobile switching center with said identity code to request network identification data for said communicating mobile station; 
 at the mobile switching center, responsively retrieving the requested network identification data using the identity code; and 
 transmitting the network identification data from said mobile switching center. 
 
     
     
       3. The method as recited in  claim 2  includes the step of:
 developing an information array at the mobile switching center including entries for each mobile station in said cell site indexed by a respective identity code. 
 
     
     
       4. The method as recited in  claim 2  wherein:
 said cellular channel further includes the mobile station communication. 
 
     
     
       5. In a cellular system comprising a plurality of cell sites each including a plurality of mobile stations in communication with a base station, and comprising a plurality of interconnected mobile switching centers each in communication with the base stations of certain cell sites, wherein each mobile switching center maintains network identification data for each mobile station being served in said certain cell sites, a method of determining the location of a mobile station originating communications within a cell site, comprising the steps of:
 transmitting from the mobile switching center a cellular channel including the network identification data for said mobile station;   receiving the transmitted network identification data; and   translating the received network identification data into geographical location information using indexable tables generated from data of trunk groups and member numbers used by each cell site and data from geographic maps of radio coverage for said cell sites.   
     
     
       6. A location-finding assembly in a cellular system, said system servicing a plurality of mobile stations through a base station connected to a mobile switching center, comprising:
 server means responsive to a location request for prompting the mobile switching center for network data on a base station;   said server means including means for receiving network data from the mobile switching center, and means for converting said network data into a corresponding geographical position profile using indexable tables generated from data of trunk groups and member numbers used by each cell site and data from geographic maps of radio coverage for said cell sites.   
     
     
       7. In a cellular network, a method comprising:
 receiving an identity and latitude and longitude coordinates of a mobile station, wherein the identity of the mobile station has been determined based on an emergency call from the mobile station and the latitude and longitude coordinates of the mobile station have been provided by the mobile station;   using the latitude and longitude coordinates to determine which type of location data among multiple types of location data is used during the emergency call, wherein a first type of location data is latitude-and-longitude-coordinates-type location data;   reformatting the latitude and longitude coordinates to enable displaying the latitude and longitude coordinates at an assistance center; and   communicating the identity and the reformatted latitude and longitude coordinates to the assistance center, which processes the emergency call using the identity and the reformatted latitude and longitude coordinates.   
     
     
       8. The method of claim 7, wherein receiving the identity and the latitude and longitude coordinates of the mobile station is from the assistance center. 
     
     
       9. The method of claim 7, wherein receiving the latitude and longitude coordinates is based on the mobile station placing the emergency call at a geographic position and the latitude and longitude coordinates reflect an approximate position of the mobile station. 
     
     
       10. The method of claim 7, wherein the mobile station that provides the received latitude and longitude coordinates includes a Global Positioning System (GPS) receiver receiving information pertaining to the latitude and longitude coordinates of the mobile station from one or more GPS satellites, wherein the mobile station is a cellular telephone. 
     
     
       11. The method of claim 7, wherein receiving the identity and the latitude and longitude coordinates of the mobile station is from a mobile switching center (MSC). 
     
     
       12. The method of claim 11, wherein the latitude and longitude coordinates provided to the MSC by the mobile station, which includes a Global Positioning System (GPS) receiver receiving information pertaining to the latitude and longitude coordinates of the mobile station, is from one or more GPS satellites, wherein the mobile station is a cellular telephone. 
     
     
       13. The method of claim 7, further comprising receiving updates to the latitude and longitude coordinates of the mobile station after receiving the emergency call from the mobile station. 
     
     
       14. The method of claim 13, further comprising providing updates to the assistance center by reformatting the updated latitude and longitude coordinates and communicating the reformatted updated latitude and longitude coordinates to the assistance center. 
     
     
       15. The method of claim 7, wherein the identity of the mobile station is a telephone number assigned to the mobile station. 
     
     
       16. In a cellular network, a method comprising:
 receiving an identity and latitude and longitude coordinates of a mobile station, wherein the identity of the mobile station has been determined based on an emergency call from the mobile station and the latitude and longitude coordinates have been provided by the mobile station based on a geographic position of the mobile station and the emergency call at the mobile station;   using the latitude and longitude coordinates to determine which type of location data among multiple types of location data is used during the emergency call, wherein a first type of location data is latitude-and-longitude-coordinates-type location data;   reformatting the latitude and longitude coordinates to enable displaying the latitude and longitude coordinates at an assistance center; and   communicating the identity and the reformatted latitude and longitude coordinates to the assistance center, which processes the emergency call using the identity and the reformatted latitude and longitude coordinates and maps the position of the mobile station based on the reformatted latitude and longitude coordinates for purposes of dispatching emergency personnel to the position of the mobile station.   
     
     
       17. In a cellular network, a method comprising:
 receiving a feature code and latitude and longitude coordinates from a mobile station, wherein the feature code corresponds to an emergency call from the mobile station;   determining an identity of the mobile station based on the feature code;   using the latitude and longitude coordinates to determine which type of location data among multiple types of location data is used during the emergency call, wherein a first type of location data is latitude-and-longitude-coordinates-type location data;   communicating the identity and the latitude and longitude coordinates of the mobile station, wherein the communicated identity and latitude and longitude coordinates assist an assistance center in locating the position of the mobile station.   
     
     
       18. The method of claim 17, wherein communicating the identity and the latitude and longitude coordinates of the mobile station to a mobile station locator that assists the assistance center by providing data corresponding to the latitude and longitude coordinates of the mobile station to the assistance center is for establishing an approximate position of the mobile station. 
     
     
       19. The method of claim 18, further comprising reformatting the received latitude and longitude coordinates for communicating the reformatted latitude and longitude coordinates to the mobile station locator. 
     
     
       20. The method of claim 17, wherein receiving the latitude and longitude coordinates is based on the mobile station placing the emergency call at a geographic position and the latitude and longitude coordinates reflect an approximate position of the mobile station. 
     
     
       21. The method of claim 17, wherein the mobile station that provides the received latitude and longitude coordinates includes a Global Positioning System (GPS) receiver receiving information pertaining to the latitude and longitude coordinates of the mobile station from one or more GPS satellites, wherein the mobile station is a cellular telephone. 
     
     
       22. The method of claim 17, wherein receiving the feature code and the latitude and longitude coordinates of the mobile station from the mobile station via a base station is associated with the mobile station. 
     
     
       23. The method of claim 17, wherein receiving the feature code and the latitude and longitude coordinates of the mobile station includes receiving a sequential string of digits, the sequential string of digits including:
 a first string of alphanumerical characters representing the identity of the mobile station, and   a second string of alphanumerical characters representing the latitude and longitude coordinates of the mobile station.   
     
     
       24. The method of claim 17, further comprising:
 recognizing the received feature code as corresponding to an emergency call;   connecting the emergency call to the assistance center in response to recognizing the received feature code; and   communicating the determined identity and received latitude and longitude coordinates of the mobile station to the assistance center.   
     
     
       25. The method of claim 17, further comprising receiving updates to the latitude and longitude coordinates of the mobile station after receiving the emergency call from the mobile station. 
     
     
       26. In a cellular network, a method comprising:
 receiving a first string of alphanumerical characters representing a feature code and a second string of alphanumerical characters representing latitude and longitude coordinates from a mobile station, wherein the feature code corresponds to an emergency call from the mobile station and the latitude and longitude coordinates reflect an approximate position of the mobile station;   determining an identity of the mobile station based on the feature code;   using the second string of alphanumerical characters to determine which type of location data among multiple types of location data is used during the emergency call, wherein a first type of location data is latitude-and-longitude-coordinates-type location data;   communicating the identity and the latitude and longitude coordinates of the mobile station, wherein the communicated identity and latitude and longitude coordinates assist an assistance center in locating the position of the mobile station.   
     
     
       27. The method of claim 7, wherein the reformatting using the latitude and longitude coordinates occurs based on the determination. 
     
     
       28. The method of claim 7, wherein a second type of location data of the multiple types of location data is cell-and-sector-type location. 
     
     
       29. The method of claim 16, wherein a second type of location data of the multiple types of location data is cell-and-sector-type location data. 
     
     
       30. The method of claim 17, wherein a second type of location data of the multiple types of location data is cell-and-sector-type location data. 
     
     
       31. The method of claim 26, wherein a second type of location data of the multiple types of location data is cell-and-sector-type location data.