| 摘要 |
<p>A mobile telephone system employs a fleet of satellites (14) and a set of gateway ground stations (10) arranged around the globe for handling communications to and from mobile communication subscriber units (12) such as mobile telephones. Signals are transmitted between a subscriber unit (10) and the nearest gateway (10) via one or more of the satellites. The gateway system is configured to process telephone call connection requests from a mobile subscriber unit (12) based upon the location of the subscriber unit. The location of the subscriber unit is employed, for example, to determine how telephone numbers are to be parsed and how to properly route emergency telephone calls to the nearest appropriate emergency service centers. Multiple location mapping schemes are employed to facilitate a determination of the location of a subscriber unit and to assist in routing emergency calls. In one implementation, each location with the service area of the system is mapped into a set of uniformly sized and shaped information cells (802). Each information cell includes pointers to data structures (806, 808) defining, among other things, the service providers that are permitted to process calls to or from that location and the nearest emergency services center. Each location is also mapped into at least one virtual service provider cell (812, 814, 816, 818, 820) which includes service provider preferences and requirements for handling a call to from that location and including a unique location identifier. A specific implementation for use with the Global System for Mobile Communication (GSM) is described.</p> |
