HANDOVER METHOD AND APPARATUS

• US 20110294509A1
• Filed: 02/04/2010
• Published: 12/01/2011
• Est. Priority Date: 02/08/2009
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Hyun-Sook, Kim, Tae-Hyeon, Kim, Lae-Young
• Granted Patent: US 8,831,612 B2
• Time in Patent Office: Days
• US Class Current: 455/436
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/24 Reselection being triggered by specific parameters
• CPC Class Codes: H04W 36/38 by fixed network equipment

Abstract

Disclosed is a method in which in case where it is inappropriate for a particular Home (e)NodeB providing a service to a particular UE to continue to provide the service on the ground of a changed status, such as overload, temporary drop due to maintenance, expiry of CSG membership for the UE, increase of temporary interference, policy change, or the like, the Home (e)NodeB transmits information on a cause that the UE performs a handover to another base station to an control entity within a network. Furthermore, it is allowed for the entity within the network to store information on the cause. In addition, if the status of the particular Home (e)NodeB is changed, then the entity within the network is allowed to perform a reverse handover for the UE to the particular Home (e)NodeB on the basis of the information on the changed status and the information on the cause.

Claims

1. A method of controlling handover in a server in charge of a control plane within a mobile communication network, the method comprising:

receiving a handover request message including information on a cause that the terminal performs handover from a Home (e)NodeB corresponding to a serving base station of the terminal to another base station;

transmitting a handover command message to the Home (e)NodeB for the terminal to perform a handover to another base station;

receiving a status report message from the Home (e)NodeB;

determining whether or not the terminal performs a reverse handover from the another base station to the Home (e)NodeB based on whether the cause has been solved if the status report message is received; and

transmitting a control message to perform the reverse handover based on the determination.

2. The method of claim 1, wherein the handover request message further comprises at least one of identification information of the terminal and information on the another base station.

3. The method of claim 1, wherein the cause comprises at least one of overload, maintenance, change of the CSG membership for the Home (e)NodeB, and policy change.

4. The method of claim 1, wherein the status report message is received from the Home (e)NodeB when the cause of the handover has been changed.

5. The method of claim 1, wherein the status report message comprises information on whether the cause of the handover is solved.

6. The method of claim 1, wherein the status report message comprises at least one of a parameter indicating that the handover cause has been solved, information on the changed status, and information on the solved cause.

7. The method of claim 1, wherein at least one of subscriber information of the terminal, policy information, membership information of the terminal for the Home (e)NodeB is considered in the determining step.

8. The method of claim 1, wherein the control message is transmitted to the another base station, and corresponds to a message indicating reverse handover, a reverse handover request message or a handover request message.

9. The method of claim 1, wherein the control message is transmitted to the Home (e)NodeB, and corresponds to a handover request message.

10. The method of claim 1, further comprising:

storing the information within the handover request message.

11. A method of handing over a terminal in a Home (e)NodeB system corresponding to a serving base station of the terminal, the method comprising:

transmitting a handover request message including information on a cause that the terminal performs handover to another base station to an entity within a network;

receiving a handover command message from the entity within the network;

delivering the handover command message to the terminal; and

transmitting a status report message to the entity within the network when a situation corresponding to the handover cause is changed.

12. The method of claim 11, wherein the status report message comprises information on whether the handover cause is solved.

13. The method of claim 11, wherein the status report message comprises at least one of a parameter indicating that the cause has been solved, information on the changed status, and information on the removed cause.

14. The method of claim 11, further comprising:

receiving a handover confirmation or acknowledgement message from the terminal subsequent to transmitting the status report message; and

transmitting a message notifying that it is recognized that handover has been performed to an entity within the network or a message indicating that handover has been completed in response to receiving the handover confirmation or acknowledgement message.

15. A server in charge of a control plane within a mobile communication network, the server comprising:

a transceiver transmitting a handover command message to a Home (e)NodeB for a terminal to perform a handover to another base station when receiving a handover request message including information on a cause that the terminal performs a handover from the Home (e)NodeB corresponding to a serving base station of the terminal to the another base station; and

a controller determining whether or not the terminal performs a reverse handover from the another base station to the Home (e)NodeB based on whether the cause has been solved if a status report message from the Home (e)NodeB through the transceiver is received.