| 摘要 |
The invention proposes a method and corresponding apparatuses for handing over a video conversation from a PS domain to a CS domain in a radio network. When signals of a network covered by the packet switch domain where the video conversation currently locates in are not good or become unavailable, as long as source MME and eNodeB detect the presence of video conversation, a procedure of handover to circuit switch domain for video bearer will be initiated, and a handover request will be transmitted to MSC server. After receiving the handover request, a control equipment in the circuit switch domain will request for resources to a target radio network requesting for the allocation of necessary communication link to the video bearer. In addition, after local UE has handed over to the target network (at this time, the communication link required for the video bearer between UE and MSC Server/MGW has already been established), local UE and MSC Server/MGW start a negotiation to establish a logical communication channel for the video conversation. Upon a successful negotiation, a logical communication channel for transferring video telephone service between MSC Server/MGW and UE is established. In this way, local UE can continue the video conversation with remote UE via MGW. |
