A METHOD AND APPARATUS FOR SEAMLESS HANDOVER IN A WIRELESS COMMUNICATION NETWORK

摘要

In a wireless communication network where base stations receive protocol data units from mobile stations for ordered, sequential transfer as service data units to an associated core network, a method and a target base station supporting seamless handover of a mobile station from a source base station to the target base station are disclosed. The target base station (16-2) comprises an interface operative to receive service data units and sequence number information forwarded from the source base station and a handover processor. The forwarded service data units comprise those service data units being held at the source base station for sequential transfer to the associated core network and the forwarded sequence number information indicates sequence numbers corresponding to the forwarded service data units. The handover processor is operative to reorder the forwarded service data units as needed at the target base station for sequential transfer from the target base station to the associated core network. The mobile station (20) for use in a wireless communication network is also disclosed. The mobile station transmits protocol data units to a base station and the base station transfers corresponding service data units to an associated core network. The mobile station is configured for supporting seamless handover from a source base station to a target base station, and comprises a handover processor that is operative to regenerate new protocol data units for missing service data units and transmit the regenerated protocol data units responsive to signalling from the target base station that indicates which service data units are missing at the target base station or equivalently indicates which service data units have been successfully received, where the regenerated protocol data units are regenerated from corresponding service data units buffered at the mobile station. In a wireless communication network where base stations receive protocol data units from mobile stations for decompression and deciphering for ordered, sequential transfer as service data units to an associated core network, a source base station (16-1) for supporting seamless handover of a mobile station from the source base station to a target base station is disclosed. The source base station comprises a handover processor and an associated interface for forwarding from the source base station to the target base station service data units and sequence number information. The forwarded service data units comprise those service data units being held at the source base station for sequential transfer to the associated core network and the forwarded sequence number information indicates sequence numbers corresponding to the forwarded service data units.