Handover Apparatus and Method in a Heterogeneous Wireless Communication System

摘要

A method and call manager for performing a handover between heterogeneous networks. The call manager is in a network having a Circuit Switching, CS, network supporting a CS call, a Long Term Evolution, LTE, network supporting a packet call, and an Internet Protocol Multimedia Subsystem, IMS, network for anchoring a call, provides handover from the CS network to the LTE network to a User Equipment, UE that uses one radio channel and can access either the CS network or the LTE network. The method comprises receiving, from a Mobile Switching Centre, MSC, of the CS network, a handover request for a CS to PS handover from the CS network to the LTE network, the handover request including International mobile subscriber identity, IMSI, for identifying the UE. The method further comprises transmitting, to the MSC, a handover response such that a handover command indicating the CS to PS handover is transmitted to the UE. The method further comprises receiving, from the UE via an enhanced NodeB, eNB, of the LTE network, a handover confirmation indicating that the CS to PS handover is completed. The method further comprises transmitting, to the MSC, a handover notification message to confirm completion of the CS to PS handover, such that the MSC releases a local resource of the UE.