System and method for performing a handover in a mobile communication system

• US 20050026615A1
• Filed: 06/16/2004
• Published: 02/03/2005
• Est. Priority Date: 06/20/2003
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Inventors: Kim, Young-Hun
• Application Number:
  US10/867,641
• Publication Number:
  US 20050026615A1
• Time in Patent Office: Days
• US Class Current: 455/436
• CPC Class Codes: H04W 36/0072 of resource information of target access point

Abstract

A system and method for performing a handover function in a mobile communication system. The system and method for controlling a User Equipment (UE) to perform a handover from a first Node B to a second Node B in a mobile communication system including a first Radio Network Controller(RNC) for managing the first Node B communicating with the UE and a second RNC for managing the second Node B to which the UE is to be handed over. The system and method comprise transmitting a handover request message including a resource to be assignment-requested to the second RNC over the first RNC; receiving resource information indicative of other assignable resources from the second RNC over the first RNC when the second Node B cannot assign the assignment-requested resource to the UE; and performing the handover using the received resource information.

Claims

1. A method for performing a handover from a first Node B to a second Node B in a mobile communication system comprising a first Radio Network Controller (RNC) for managing the first Node B communicating with a User Equipment (UE) and a second RNC for managing the second Node B to which the UE is to be handed over to, comprising the steps of:

transmitting a handover request message comprising a resource to be assignment-requested to the second RNC via the first RNC;

receiving resource information indicative of other assignable resources from the second RNC over the first RNC when the second Node B is full of the assignment-requested resource to the UE; and

performing the handover using the received resource information.

2. The method according to claim 1, wherein the performing step further comprising:

selecting a single resource from among the assignable resources according to a predetermined sequence if the number of the assignable resources is greater than ‘

2’

; and

performing the handover using the selected resource.

3. The method according to claim 2, wherein the selecting step further comprises:

selecting a resource having the same frequency as the assignable resources.

4. The method according to claim 2, wherein the performing step further comprises the step of:

transmitting a handover request message for requesting to assign the selected resource to the second RNC via the first RNC.

5. The method according to claim 1, wherein the handover request message comprises a service category, a cell Identifier (ID), a code, and a reception power information of the UE.

6. A method for performing a handover using a second Radio Network Controller (RNC) in a mobile communication system comprising a first RNC for managing a first Node B communicating with a User Equipment (UE) and a second RNC for managing a second Node B to which the UE is to be handed over, comprising the steps of:

receiving a handover request message comprising resource which the UE has requested via the first RNC;

determining whether the second Node B can assign the requested resource;

searching for other assignable resources in the second Node B when the second Node B is full of the requested resource transmitting a message comprising resource information of the assignable resources to the first RNC if assignable resources are searched; and

performing a handover using the resource information.

7. The method according to claim 6, wherein the performing step further comprises:

transmitting a message indicative of a used or unused state of the assignable resources to the UE from the first RNC if the resource information includes two or more assignable resources;

receiving a handover request message including a resource selected from among the assignable resources to the first RNC from the UE; and

performing the handover using the selected resource.

8. The method according to claim 6, wherein the performing step further comprises:

transmitting a handover command message including the single resource to the UE from the first RNC if the information includes a single resource; and

receiving a successful handover message to the first RNC from the UE.

9. The method according to claim 6, wherein the handover request message includes service category, cell Identifier (ID), code, and reception power information of the UE.

10. A communication system for performing a handover from a first Node B to a second Node B, comprising:

a first Radio Network Controller (RNC) adapted to manage the first Node B in communication with a User Equipment (UE) and

a second RNC adapted to manage the second Node B to which the UE is to be handed over to; and

the UE adapted to transmit a handover request message comprising a resource to be assignment-requested to the second RNC via the first RNC, receive resource information indicative of other assignable resources from the second RNC via the first RNC when the second Node B is full of the assignment-requested resource to the UE, and perform the handover using the received resource information.

11. The system according to claim 10, wherein the UE is further adapted to select a single resource from among the assignable resources according to a predetermined sequence if the number of the assignable resources is greater than ‘

2’

, and perform the handover using the selected resource.

12. The system according to claim 11, wherein the UE is further adapted to select a resource having the same frequency as the assignable resources.

13. The system according to claim 11, wherein the UE is further adapted to transmit a handover request message for requesting to assign the selected resource to the second RNC via the first RNC.

14. The system according to claim 10, wherein the handover request message includes service category, cell Identifier (ID), code, and reception power information of the UE.

15. A communication system for performing a handover from a first Node B to a second Node B, comprising:

a first Radio Network Controller (RNC) adapted to manage the first Node B in communication with a User Equipment (UE); and

a second RNC adapted to manage the second Node B to which the UE is to be handed over to, determine whether the second Node B can assign the requested resource, search for other assignable resources in the second Node B when the second Node B is full of the assignment requested resource, transmit a message comprising resource information of the assignable resources to the first RNC if assignable resources are searched, and perform a handover using the resource information.

16. The system according to claim 15, wherein the first RNC is further adapted to transmit a message indicative of a used or unused state of the assignable resources to the UE if the resource information includes two or more assignable resources, receive a handover request message including a resource selected from among the assignable resources from the UE, and perform the handover using the selected resource.

17. The system according to claim 15, wherein the first RNC is further adapted to transmit a handover command message comprising the single resource to the UE if the information comprises a single resource, and receive a successful handover message from the UE.

18. The system according to claim 15, wherein the handover request message comprises a service category, a cell Identifier (ID), a code, and a reception power information of the UE.