Mobile switchboard, mobile unit, mobile communication system, and position-registration extending method

Abstract

A mobile unit transmits a request for position registration to a network when moving from a first area to a second area. When the number of incoming calls does not exceed a threshold and the number of movements between the first area and the second area exceeds a threshold, a mobile switchboard combines the first area and the second area into an extended area, and informs the mobile unit of the extended area.

1 . A mobile communication system including a base station and a mobile station comprising:
 the base station which transmits, to the mobile station, area list information including a first position registration area and a second position registration area, and   the mobile station which receives the area list information from the base station, and controls execution of an updating such that the updating is not executed when the mobile station detects a change to a new area information that is included in the area list information.   
     
     
         2 . A method for utilizing a mobile communication system including a base station and a mobile station, the method comprising:
 at the base station,
 transmits, to the mobile station, area list information including a first position registration area and a second position registration area, and 
   at the mobile station,   receives the area list information from the base station, and controls execution of an updating such that the updating is not executed when the mobile station detects a change to a new area information that is included in the area list information.