Apparatus and method for supporting intra-base station handover in a multi-hop relay broadband wireless communication system

• US 20100208692A1
• Filed: 02/12/2010
• Published: 08/19/2010
• Est. Priority Date: 02/13/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Rakesh, Taori, Baek, Young-Kyo, Chang, Young-Bin, Kang, Hyun-Jeong, Son, Jung-Je
• Granted Patent: US 9,031,036 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 36/0055 Transmission or use of information for re-establishing the radio link
• CPC Class Codes: H04W 36/0064 of control information between different access points
• CPC Class Codes: H04W 84/047 using dedicated repeater stations

Abstract

An apparatus is capable of supporting an intra-BS handover of a Mobile Station (MS) that can distinguish a Relay Station (RS) and a Base Station (BS) in a multi-hop relay broadband wireless communication system. A handover of an MS in a multi-hop relay wireless communication system includes receiving a neighbor advertisement message. When a handover command message that initiates a handover to a target node is received, information on a target node is acquired, and an upper BS of the target node is identified. When the identified upper BS of the target node is the same as an upper BS of the serving node, control information that has been previously used in a serving node is used in the target node, and communication with the target node is performed.

Claims

1. A method of handover for a Mobile Station (MS) in a multi-hop relay wireless communication system, the method comprising:

receiving a neighbor advertisement message from a serving node, the neighbor advertisement message comprising information for at least one of a neighbor node and an upper Base Station (BS) that controls the neighbor node;

when a handover command message is received from the serving node, acquiring information on a target node using the handover command message;

identifying an upper BS of the target node using the acquired information on the target node and the information on at least one of the neighbor node and the upper BS that controls the neighbor node; and

when the identified upper BS of the target node is the same as an upper BS of the serving node, using control information, which has been used in the serving node, to communicate with the target node.

2. The method of claim 1, wherein the control information comprises at least one of a key used for communication, a station identifier (ID), and a service flow and connection setting information.

3. The method of claim 2, further comprising sending to the target node a ranging request message that comprises a key that has been used to communicate with the serving node.

4. The method of claim 2, further comprising generating a key used to communicate with the serving node, based on a BSID during a network entry into the serving node.

5. The method of claim 4, wherein generating the key used to communicate with the serving node comprises:

registering to a network to search an access node for data transfer;

acquiring a synchronization for the searched access node;

when the access node is an access Relay Station (RS), acquiring a base station identifier (BSID) of an upper BS of the access RS from a system configuration information; and

generating the key used for communication, based on the acquired BSID of the upper BS of the access RS.

6. The method of claim 5, further comprising:

when the access node is an access BS, acquiring a BSID of the access BS; and

generating the key used for communication, based on the acquired BSID of the access BS.

7. The method of claim 1, further comprising, when the identified upper BS of the target node is different from the upper BS of the serving node, generating a new key to communicate with the target node.

8. A method for a Base Station (BS) to support a handover of a Mobile Station (MS) in a multi-hop relay wireless communication system, the method comprising:

sending a handover command message to the MS through a serving node of the MS;

determining whether a ranging request message received from the MS through a target node comprises information on a key that has been used by the MS in a communication with the serving node; and

responsive to the ranging request message comprising the information on the key that has been used by the MS in the communication with the serving node, sending a ranging response message to the MS through the target node without exchanging control information of the MS with a gateway.

9. The method of claim 8, wherein the control information comprises at least one of a key used when performing communication, a station identifier (ID), and a service flow and connection setting information.

10. The method of claim 8, wherein the key that has been used in the communication with the serving node is a key generated by the MS based on a base station identifier (BSID) acquired during a network entry into the serving node.

11. The method of claim 8, further comprising, responsive to the ranging request message comprising information on a new key generated for a communication with the target node, exchanging the control information of the MS with the gateway and sending the ranging response message to the MS through the target node.

12. A method for handover of a Mobile Station (MS) in a multi-hop relay wireless communication system, the method comprising:

receiving a handover command message from a serving node;

determining whether the handover is an intra-BS handover based on an indicator comprised in the handover command message; and

when the handover is the intra-BS handover, using, in a target node, a control information that has been used in the serving node and communicating with the target node.

13. A method for a Base Station (BS) to support a handover of a Mobile Station (MS) in a multi-hop relay wireless communication system, the method comprising:

responsive to determining a need for the MS to handover to a target node, determining whether the target node exists within the same BS;

setting an indicator that indicates whether the handover is an intra-BS handover; and

generating a handover command message comprising the set indicator.

14. An apparatus for handover of a Mobile Station (MS) in a multi-hop relay wireless communication system, the apparatus comprising:

a serving node configured to send to the MS a neighbor advertisement message, the neighbor advertisement message comprising information on at least one of a neighbor node and an upper Base Station (BS) that controls the neighbor node, and send to the MS a handover command message that commands a handover to a target node; and

the MS configured to receive the neighbor advertisement message from the serving node to acquire information on at least one of the neighbor node and the upper BS that controls the neighbor node, receive the handover command message from the serving node to acquire information on the target node, identify an upper BS of the target node using the acquired information on the target node and the information on at least one of the neighbor node and the upper BS that controls the neighbor node, and, when the identified upper BS of the target node is the same as an upper BS of the serving node, use a control information that has been used in the serving node, to communicate with the target node.

15. The apparatus of claim 14, wherein the control information comprises at least one of a key used for communication, a station identifier (ID), and a service flow and connection setting information.

16. The apparatus of claim 15, wherein the MS is further configured to send to the target node a ranging request message that comprises a key that has been used to communicate with the serving node.

17. The apparatus of claim 15, wherein the MS is further configured to generate the key used to communicate with the serving node, using a base station identifier (BSID) during a network entry into the serving node.

18. The apparatus of claim 17, wherein the MS is further configured to register to a network to search an access node for data transfer, acquire a synchronization for the searched access node, acquire the BSID from a system configuration information when the access node is a Relay Station (RS), and generate the key used for communication, based on the acquired BSID.

19. The apparatus of claim 18, wherein, when the access node is a BS, the MS is further configured to generate the key used for communication, based on an ID of the BS.

20. The apparatus of claim 14, wherein, when the identified upper BS of the target node is different from the upper BS of the serving node, the MS is further configured to generate a new key to communicate with the target node.

21. The apparatus of claim 14, further comprising an upper BS that controls the serving node, the upper BS configured to send to the serving node the handover command message, when a ranging request message is received from the MS through the target node, determine whether the ranging request message comprises information on a key that has been used by the MS to communicate with the serving node, and when the ranging request message comprises the information on the key that has been used by the MS to communicate with the serving node, send a ranging response message to the MS through the target node without exchanging control information of the MS with a gateway.

22. The apparatus of claim 21, wherein, when the ranging request message comprises information on a new key generated to communicate with the target node, the upper BS is further configured to exchange the control information of the MS with the gateway and send a ranging response message to the MS through the target node.

23. An apparatus for handover of a Mobile Station (MS) in a multi-hop relay wireless communication system, the apparatus comprising:

a serving node configured to send to an MS a handover command message to initiate handover to a target node;

the MS configured to determine whether the handover is an intra-BS handover based on an indicator comprised in the handover command message and, when the handover is the intra-BS handover, use, in the target node a control information that has been used in the serving node and communicate with the target node, wherein the indicator indicates whether the handover is the intra-BS handover.

24. The apparatus of claim 23, further comprising an upper BS that controls the serving node, the upper BS configured to, when there is a need for the MS to handover to the target node, determine whether the target node exists within the same BS, set the indicator that indicates whether the handover is the intra-BS handover, generate the handover command message comprising the indicator, and send the handover command message to the serving node.