Method for acquiring information of home node B, method for balancing load, and apparatuses therefor

• US 8,855,664 B2
• Filed: 09/02/2010
• Issued: 10/07/2014
• Est. Priority Date: 09/02/2010
• Status: Active Grant

• Current Assignee: ZTE Corporation
• Original Assignee: ZTE Corporation
• Inventors: Gao, Yin, Chen, Zhongming, Xi, Jin
• Primary Examiner(s): RAMPURIA, SHARAD K
• Application Number:
  US13/634,571
• Publication Number:
  US 20130183980A1
• Time in Patent Office: 1,496 Days
• Field of Search: 370/329, 370331-338, 455436-453
• US Class Current: 455/453
• CPC Class Codes: H04W 36/0061 of neighbour cell information
• CPC Class Codes: H04W 36/0072 of resource information of target access point
• CPC Class Codes: H04W 36/0077 of access information of target access point
• CPC Class Codes: H04W 36/04 Reselecting a cell layer in multi-layered cells
• CPC Class Codes: H04W 36/22 for handling the traffic
• CPC Class Codes: H04W 36/30 by measured or perceived connection quality data

Abstract

The present invention discloses a method for acquiring information of a home NodeB, a method for balancing load, and implementation apparatuses thereof, which are used to solve the problem how to guide a UE to move to an appropriate home NodeB when a macro cell performs load balancing. In the present invention, information of a target NodeB is acquired actively through a macro NodeB, and according to an access type of the target NodeB, subscribers of the macro NodeB are timely balanced to the home NodeB which can provide services, thereby reducing a call drop rate resulted from blind handover. Since measurement information of the UE is fully considered, success rate of balancing handover is enhanced, and the object of performing effective load balancing in a home NodeB environment is achieved.

Claims

1. A method for implementing load balancing in a home NodeB environment, comprising:

a macro NodeB actively sending a home NodeB information request message to target home NodeBs so as to acquire information of the target home NodeBs in following way;

the macro NodeB sending the home NodeB information request message to the target home NodeBs;

the target home NodeBs feeding back a home NodeB information request response message to the macro NodeB after receiving the home NodeB information request message;

wherein, the home NodeB information request message and home NodeB information request response message are implemented through a newly added X2 interface message or a newly added S1 interface message;

if the home NodeB information request message and home NodeB information request response message are implemented through a S1 interface, the home NodeB information request message and home NodeB information request response message performs passthrough through a Mobility Management Entity (MME) and a home NodeB gateway;

when the load of a macro cell exceeds a preset threshold, according to the obtained information of the target home NodeBs and a measurement report reported by a User Equipment (UE), the macro NodeB selecting the target home NodeB with better signal quality for the UE to perform handover.

2. The method according to claim 1, wherein,

besides a global identifier of a target NodeB and Tracking Area Identifier (TAI) information, information of the target NodeB in the home NodeB information request response message comprises one or more items in the following information:

a cell type of a target NodeB cell, an EUTRAN Cell Global Identifier (ECGI), Closed Subscriber Group Identifier (CSG ID) information, an access attribute of the home NodeB and geographic location information of the home NodeB; and

the type of the target NodeB cell comprises;

the macro cell and a home NodeB cell, or a type of cell coverage radius;

the access attribute of the home NodeB comprises;

an Open mode, a Close mode and a Hybrid mode.

3. The method according to claim 1, before the macro NodeB acquires the information of the target home NodeB, further comprising:

the UE discovering a new home NodeB cell in the macro cell, and reporting a Physical Cell Identifier (PCI) of the newly discovered home NodeB cell to a current serving macro NodeB through an automatic neighboring cell discovery flow;

the macro NodeB guiding the UE to read a system broadcast of the newly discovered home NodeB cell, and acquiring the EUTRAN Cell Global Identifier (ECGI) or the ECGI and Closed Subscriber Group Identifier (CSG ID) information of the newly discovered home NodeB cell.

4. The method according to claim 1, after the macro NodeB acquires home NodeB information of the newly discovered home NodeB cell, further comprising:

the macro NodeB judging access attribute of the newly discovered home NodeB cell through the Physical Cell Identifier (PCI), or judging the access attribute of the newly discovered home NodeB cell through the access attribute of the home NodeB carried in the home NodeB information request response message;

the macro NodeB executing a handover operation for the purpose of load balancing to the target home NodeB of which the access attribute is an Open mode or Hybrid mode.

5. The method according to claim 4, wherein, with regard to the target home NodeB in the load balancing being the home NodeB in an inter-frequency Open mode or inter-frequency Hybrid mode, the macro NodeB sends a Radio Resource Control (RRC) reallocation message to the UE, deletes S-measure configuration information, makes the UE to be able to perform inter-frequency measurement, and according to the signal quality of the home NodeB cell in an intra-frequency measurement report reported by the UE in the macro cell, selects the UE of which a signal quality measurement result of the home NodeB cell is higher to perform handover.

6. An apparatus for implementing load balancing in a home NodeB environment comprising:

a request module in a macro Node B actively send a home NodeB information request message to a target home NodeBs so as to acquire information of the target home NodeBs;

a response module in target home NodeBs after receiving the home NodeB information request message, feed back a home NodeB information request response message to the request module; and

a balancing module in a macro Node B, when the load of a macro cell exceeds a preset threshold, according to the obtained information of the target home NodeBs and a measurement report reported by a UE, select the target home NodeB with better signal quality for the UE to perform handover;

wherein,

the home NodeB information request message and the home NodeB information request response message are implemented through a newly added S1 interface message or a newly added X2 interface message;

wherein if the home NodeB information request message and home NodeB information request response message are implemented through an S1 interface, the apparatus further comprises a passthrough module located at an Mobility Management Entity (MME) and a home NodeB gateway, used to pass through the home NodeB information request message and home NodeB information request response message between the request module and response module.

7. The apparatus according to claim 6, wherein, besides a global identifier of a target NodeB and Tracking Area Identifier (TAI) information, information of the target NodeB in the home NodeB information request response message comprises one or more items in the following information:

a cell type of a target NodeB cell, an EUTRAN Cell Global Identifier (ECGI), Closed Subscriber Group Identifier (CSG ID) information, an access attribute of the home NodeB and geographic location information of the home NodeB;

the type of the target NodeB cell comprises;

the macro cell and a home NodeB cell, or a type of cell coverage radius;

the access attribute of the home NodeB comprises;

an Open mode, a Close mode and a Hybrid mode.

8. The apparatus according to claim 6, further comprising:

a cell discovery module, used to;

before acquiring the information of the target home NodeB, receive a PCI of a newly discovered cell reported by the UE, guide the UE to read a system broadcast of the newly discovered cell, and acquire an ECGI or the ECGI and CSG ID information of the newly discovered cell;

the balancing module judges an access attribute of the newly discovered cell according to the Physical Cell Identifier (PCI) or the information of the target home NodeB acquired by a home NodeB information acquisition module, and when the access attribute of the newly discovered cell is an Open mode or Hybrid mode, executes a handover operation for the purpose of load balancing.

9. The apparatus according to claim 8, wherein, with regard to the target home NodeB in the load balancing being a home NodeB in an inter-frequency Open mode or inter-frequency Hybrid mode, the balancing module sends an RRC reallocation message to the UE, deletes S-measure configuration information, makes the UE can perform inter-frequency measurement, and according to the signal quality of the home NodeB cell in an intra-frequency measurement report reported by the UE in the macro cell, selects the UE of which a signal quality measurement result of the home NodeB cell is higher to perform handover.

10. A method for a macro NodeB acquiring information of a home NodeB, comprising:

the macro NodeB actively sending a home NodeB information request message to target home NodeBs so as to acquire information of the target home NodeBs in the following way;

the macro NodeB sending the home NodeB information request message to the target home NodeB;

the target home NodeB feeding back a home NodeB information request response message to the macro NodeB after receiving the home NodeB information request message;

wherein, the home NodeB information request message and home NodeB information request response message are implemented through a newly added S1 interface message or a newly added X2 interface message;

if the home NodeB information request message and home NodeB information request response message are implemented through an S1 interface, the home NodeB information request message and home NodeB information request response message performs passthrough through a Mobility Management Entity (MME) and a home NodeB gateway.

11. The method according to claim 10, wherein,

besides a global identifier of a target NodeB and Tracking Area Identifier (TAI) information, information of the target NodeB in the home NodeB information request response message comprises one or more items in the following information:

a cell type of a target NodeB cell, an EUTRAN Cell Global Identifier (ECGI), Closed Subscriber Group Identifier (CSG ID) information, an access attribute of the home NodeB and geographic location information of the home NodeB.

12. An apparatus for a macro NodeB acquiring information of a home NodeB, comprising:

a request module in a macro Node B actively send a home NodeB information request message to target home NodeBs so as to acquire information of the target home NodeBs;

a response module in target home NodeBs, after receiving the home NodeB information request message, feed back a home NodeB information request response message to the request module;

wherein, besides a global identifier of a target NodeB and Tracking Area Identifier (TAI) information, information of the target NodeB in the home NodeB information request response message comprises one or more items in the following information;

a cell type of a target NodeB cell, an EUTRAN Cell Global Identifier (ECGI), Closed Subscriber Group Identifier (CSG ID) information, an access attribute of the home NodeB and geographic location information of the home NodeB;

wherein, the home NodeB information request message and home NodeB information request response message are implemented through a newly added S1 interface message or a newly added X2 interface message;

wherein, if the home NodeB information request message and home NodeB information request response message are implemented through an S1 interface, the apparatus further comprises a passthrough module located at an Mobility Management Entity (MME) and a home NodeB gateway, used to pass through the home NodeB information request message and home NodeB information request response message between the request module and response module.