Patent ID: 9414302
Filing Date: 2016-08-09
CPC Classification: H04W

Claim Text:
1. A radio communication system comprising: a first base station employing a first radio access technology and having a first cover area; a second base station employing the first radio access technology and having a second cover area that is partly or entirely included in the first cover area, the second base station being a CSG (Closed Subscriber Group) type base station communicating with only registered mobile stations that are registered in advance; a third base station employing a second radio access technology different from the first radio access technology and having a third cover area that is partly or entirely included in the first cover area; a mobile station including communication circuitry that is capable of communicating with each of the first base station and the second base station by employing the first radio access technology, and capable of communicating with the third base station by employing the second radio access technology; and a home subscriber server that correlates the second base station, which is the CSG type base station, with the communicable mobile station, wherein information indicating presence of the third base station is included in a database of the home subscriber server, the database being made correspondent to the second base station, the home subscriber server notifies, to the mobile station, information indicating the presence of the third base station in a case that the mobile station has entered into an overlapped area of the second cover area and the third cover area, the mobile station receives, in accordance with the notification from the home subscriber server, the information indicating the presence of the third base station, the second base station and the third base station are provided as a composite device installed in a single housing, and in a case that an update occurs on a database in the second base station, the second base station notifies the update to the home subscriber server which notifies the update to the mobile station.