Base station synchronization during soft handover

摘要

The present invention relates to a data transmission method and data packet retransmission method for use in a mobile communication system comprising a communication terminal and a plurality of base stations, wherein the communication terminal is in communication with the plurality of base stations during a soft handover. Further, the present invention relates to a base station executing the data transmission method and the data retransmission method. To prohibit the wrong combination of data packets in base stations participating in the active set of a particular communication terminal the invention provides a method for exchanging control information between base stations participating in a soft handover to synchronize their buffers.