Method for handover between different radio access schemes and wireless communication system

Abstract

In a wireless communication system including a plurality of base stations each supporting at least one of two or more radio access schemes and at least one mobile station capable of performing communication by using the two or more radio access schemes, before the mobile station moves from a source base station to a target base station, the target base station notifies the mobile station, via the source base station, of a transparent container containing uplink radio access information that specifies a radio access scheme enabling at least an initial connection to be made. Thus, the mobile station identifies the radio access scheme supported by the target base station from the transparent container before moving from the source base station to the target base station.

1 . A method for handover between base stations in a wireless communication system which includes a plurality of base stations and at least one mobile station, wherein each of the plurality of base stations supports at least one of a plurality of radio access schemes and the mobile station is operable in the plurality of radio access schemes, the method comprising:
 before the mobile station moves from a first base station to a second base station, the second base station notifying the mobile station of transfer information which includes information about communication for establishment of synchronization with the second base station; and   before the mobile station moves from the first base station to the second base station, the mobile station recognizing the information about communication for establishment of synchronization with the second base station from the transfer information.   
     
     
         2 . The method according to  claim 1 , wherein in response to a handover request received from the first base station, the second base station transmits back to the first base station handover acceptance information including the transfer information, wherein the transfer information is transferred from the first base station to the mobile station. 
     
     
         3 . The method according to  claim 1 , wherein
 in response to a HANDOVER REQUEST message received from the first base station, the second base station transmits back to the first base station a HANDOVER REQUEST ACKNOWLEDGE message which includes, as part thereof, the transfer information; and   the first base station, when having received the HANDOVER REQUEST ACKNOWLEDGE message, transmits a HANDOVER COMMAND including the transfer information to the mobile station.   
     
     
         4 . A base station in a wireless communication system which includes a plurality of radio access schemes, comprising:
 a communication section for communicating with a mobile station in at least one of the plurality of radio access schemes; and   a notifying section for notifying the mobile station of transfer information which includes information about communication for establishment of synchronization with the base station before the mobile station moves from another base station to the base station.   
     
     
         5 . The base station according to  claim 4 , wherein in response to a handover request received from the other base station, the notifying section transmits back to the other base station handover acceptance information including the transfer information. 
     
     
         6 . The base station according to  claim 4 , wherein
 in response to a HANDOVER REQUEST message received from the other base station, the notifying section transmits back to the other base station a HANDOVER REQUEST ACKNOWLEDGE message which includes, as part thereof, the transfer information.   
     
     
         7 . A mobile station which is capable of communicating with a plurality of base stations, each of which supports at least one of a plurality of radio access schemes, comprising:
 a receiver for receiving transfer information via a first base station before the mobile station moves from the first base station to a second base station, wherein the transfer information includes information about communication for establishment of synchronization with the second base station; and   a sync establishment section for establishing synchronization with the second base station according to the information included in the transfer information.   
     
     
         8 . The mobile station according to  claim 7 , wherein the receiver receiving the transfer information via the first base station, wherein the second base station transmits the transfer information by handover acceptance information indicating handover acceptance. 
     
     
         9 . A wireless communication system comprising a plurality of base stations and at least one mobile station, wherein each of the plurality of base stations supports at least one of a plurality of radio access schemes and the mobile station is operable in the two or more radio access schemes, wherein
 the base station comprises:   a communication section which is capable of communication in at least one of the plurality of radio access schemes; and   a notifying section for notifying the mobile station of transfer information which includes information about communication for establishment of synchronization with the base station before the mobile station moves from another base station to the base station, and   the mobile station comprises:   a receiver for receiving transfer information via the other base station before the mobile station moves from the other base station to the base station, wherein the transfer information includes information about communication for establishment of synchronization with the base station; and   a sync establishment section for establishing synchronization with the base station according to the information included in the transfer information.   
     
     
         10 . The wireless communication system according to  claim 9 , wherein in response to a handover request received from the other base station, the notifying section transmits back to the other base station handover acceptance information including the transfer information.