METHOD AND APPARATUS FOR POWER SAVING OF FEMTO BASE STATION USING ANR FUNCTION IN WIRELESS COMMUNICATION SYSTEM

• US 20110287756A1
• Filed: 05/20/2011
• Published: 11/24/2011
• Est. Priority Date: 05/20/2010
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Lee, Chan Yong, Kim, Hong Soog, CHO, Eun Seon, Park, Nam Hoon
• Granted Patent: US 8,706,099 B2
• Time in Patent Office: Days
• US Class Current: 455/418
• CPC Class Codes: H04W 52/0206 in access points, e.g. base stations access point devices per se H04W88/08
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Provided are a method and an apparatus for power saving of a femto base station operating as a CSG cell in a wireless communication system. A femto base station according to an exemplary embodiment of the present invention includes: a reception unit receiving signals from adjacent second femto base stations; a transmission unit transmitting signals to second femto base stations, and a control unit controlling to be transitioned to an active mode when a mode transition command is received from at least one second femto base station while operating in a sleep mode, in a wireless communication system constituted by a plurality of femto base stations using automatic neighbor relation (ANR).

Claims

1. A femto base station using an automatic neighbor relation (ANR) function, comprising:

a reception unit receiving signals from adjacent femto base stations; and

a control unit controlling the femto base station to be transitioned to an active mode when the femto base station receives a mode transition command from at least one of the adjacent femto base stations when the femto base station operates in a sleep mode.

2. The femto base station of claim 1, wherein the reception unit receives information configured in any one format of a message, a signature, and the like from at least one of the adjacent femto base stations.

3. The femto base station of claim 1, wherein the femto base station establishes connected with the adjacent femto base stations by using at least one of interface of X2 interface and S1 interface.

4. The femto base station of claim 3, wherein when power is supplied, the femto base station receives a neighbor list including identifiers of the adjacent femto base stations required for the operation of ANR from an operation and maintenance center (OMC) while performing a base station self-configuration procedure, and

the femto base station establishes connected with the adjacent femto base stations by using at least one interface of the X2 interface and the S1 interface by using the neighbor list.

5. The femto base station of claim 1, further comprising a transmission unit transmitting mode transition information to the adjacent femto base stations in accordance with a control of the control unit when the femto base station is transitioned to the active mode.

6. The femto base station of claim 1, wherein the femto base station operates as a closed subscriber group (CSG) cell and is accessible by only a terminal (member terminal) which is allowed to access, and

the control unit controls the femto base station to be transitioned to the sleep mode when all the member terminals do not exist in its own service coverage after the femto base station is transitioned to the active mode.

7. The femto base station of claim 6, further comprising a transmission unit transmitting mode transition information to the adjacent femto base stations in accordance with the control of the control unit when the femto base station is transitioned to the sleep mode.

8. The femto base station of claim 1, further comprising a neighbor relation (NR) table storing the information received from the adjacent femto base stations.

9. The femto base station of claim 8, wherein the NR table stores at least one of a physical cell identity (PCI) which is a physical layer identifier for identifying a femto cell of the adjacent femto base station, a target cell identity (TCI) which is a global cell identifier representing an identifier of each femto base station, OMC control allocation attributes, a femto cell type, a current operation mode state of the femto base station, and a list of member terminals which are allowed to access for each femto cell.

10. A method of controlling a femto base station operating as a closed subscriber group cell and to which only a terminal allowed to access is accessible, comprising:

determining whether or not the terminal exists in its own service coverage in a first femto base station; and

transmitting mode transition information to adjacent second femto base stations and transitioning an active mode to a sleep mode when all the terminals do not exist in the service coverage on the basis of the determination result.

11. The method of claim 10, further comprising:

receiving a neighbor list including an identifier of a femto base station required for the operation of ANR from an operation and maintenance center (OMC) while the first femto base station performs a base station self-configuration procedure;

establishing connection with the adjacent second femto base stations by using at least one face of X2 interface and S1 interface by using the neighbor list;

allowing the first femto base station to receive the information from the connected second femto base stations; and

storing the received information in a neighbor relation (NR) table.

12. The method of claim 11, wherein the information stored in the NR table includes at least one of a physical cell identity (PCI) which is a physical layer identifier for identifying a femto cell of the second femto base station, a target cell identity (TCI) which is a global cell identifier representing an identifier of the second femto base station, OMC control allocation attributes, a femto cell type, a current operation mode state of the second femto base station, and a list of member terminals which are allowed to access the second femto base stations.

13. The method of claim 10, wherein the determining includes determining whether or not the terminal accessing the first femto base station within a predetermined reference time exists.

14. The method of claim 10, wherein the determining includes determining whether or not the terminals exist in the service coverage by comparing the inputted service coverage of the first femto base station with the positional informant of the terminals acquired from the terminals.

15. The method of claim 10, wherein the determining includes:

receiving an access verification message from the terminal which enters the service coverage; and

comparing an identifier of the terminal stored in the first femto base station with an identifier of the terminal stored in the first femto base station.

16. A method of controlling a femto base station, comprising:

allowing a first femto base station to transmit a mode transition command to a second femto base station which is operating in a sleep mode;

when the second femto base station receives the mode transition command from the first femto base station, transitioning the second femto base station to an active mode; and

allowing the second femto base station to transmit mode transition information to an adjacent femto base station.

17. The method of claim 16, wherein the transmitting of the mode transition command includes:

allowing the first femto base station to determine whether or not terminals which are allowed to access the second femto base station exist in its own service coverage; and

transmitting the mode transition command configured in any one format of a message, a signature, and the like to the second femto base station when even any one of the terminals which are allowed to access the second femto base station exists in its own service coverage on the basis of the determination result.