Method and system for improving the performance of inter-systems handovers

摘要

A preferred embodiment of an invention is disclosed, whereby the size of certain (e.g., S-RNTI and scrambling code number) Information Elements (IEs) in the UTRAN RRC “HANDOVER TO UTRAN COMMAND” message can be reduced, by reserving a subrange of the IE parameter values for exclusive use by the User Equipment (UE) which is performing an inter-Radio Access Technology (RAT) handover to a UTRAN. For example, the lowest values of scrambling code number or S-RNTI number can be reserved for initial assignment to a UE performing a handover from one system network to the UTRAN. Upon completion of the handover procedure, the UTRAN can assign another scrambling code number or S-RNTI number to that UE. Consequently, by significantly reducing the size of the IEs used in the HANDOVER TO UTRAN COMMAND message, additional (e.g., optional) parameters may also be used in the same message.