Base station switchover method

This invention discloses a base station switching method including: setting the automatic repeat request L1 cache in the media access control layer of base station and the L2 one in the Packet Data Access Gateway convergence protocol layer, and installing the switching preparation and decision threshold in the measurement module. When the measurement report from source base station to judge user' s equipment reaches the switching preparation threshold, it maintains the synchronization of two-level cache. When the measurement report reaches the switching decision threshold, it sends to the target base station the protocol data unit of packet data convergence protocol layer in L2 cache, and carries completing signs on the final packet. The target base station receives the above data unit in the L1 cache, and deals with them to be media accessing to the control layer protocol data unit. After completing the corresponding treatments, the target station requires to access Gateway to carry switching operation.