Apparatus and method for managing an access mode of a node b in a wireless communication system

Abstract

An apparatus and a method for managing an access mode of an NB in a wireless communication system. In the method for changing the access mode of a second NB at a first NB or a CN, an access mode change of the second NB is determined. An access mode change request message is transmitted to the second NB, requesting the access mode change of the second NB. An access mode change response message including an access mode control result is received from the second NB.

1 . A method for changing an access mode of a second Node B (NB) by a first NB or a Core Network (CN) of a wireless communication system, the method comprising:
 determining to change the access mode of the second NB;   transmitting, to the second NB, an access mode change request message that requests an access mode change of the second NB; and   receiving, from the second NB, an access mode change response message including an access mode control result.   
     
     
         2 . The method of  claim 1 , wherein determining to change the access mode of the second NB comprises:
 receiving a measurement report message from a User Equipment (UE);   determining whether the UE receives interference that is greater than a reference level from the second NB, based on the received measurement report message; and   when the UE receives interference that is greater than the reference level from the second NB, determining to change of the access mode of the second NB.   
     
     
         3 . The method of  claim 1 , wherein determining, by the first NB, to change the access mode of the second NB comprises:
 exchanging, with a plurality of NBs, a load information message including cell load information;   determining whether coverage areas of the first NB and the second NB overlap each other, whether a cell load of the first NB is greater than a reference level, and whether a cell load of the second NB is less than a reference level, based on load information for each cell collected through the load information message exchange, and an inter-NB coverage mapping table; and   when the coverage areas of the first NB and the second NB overlap each other, the cell load of the first NB is greater than the reference level, and the cell load of the second NB is less than the reference level, determining to change the access mode of the second NB.   
     
     
         4 . The method of  claim 1 , wherein determining, by the CN, to change the access mode of the second NB comprises:
 receiving, from a plurality of NBs, load information messages include cell load information;   determining whether an NB whose coverage overlaps that of the second NB and whose cell load is greater than a reference level exists, and whether a cell load of the second NB is less than the reference level, based on load information for each cell collected through the reception of the load information messages, and an inter-NB coverage mapping table; and   when the NB whose coverage overlaps that of the second NB and whose cell load is greater than a reference level exists, and that the cell load of the second NB is less than the reference level, determining to change the access mode of the second NB.   
     
     
         5 . A method for changing an access mode by a Node B (NB) of a wireless communication system, the method comprising:
 receiving an access mode change request message requesting change of the access mode of the NB from another NB or a Core Network (CN);   determining whether to allow the access mode to change; and   transmitting an access mode change response message including an access mode control result to the another NB or the CN.   
     
     
         6 . The method of  claim 5 , wherein the NB is a femto NB, further comprising:
 transmitting an access mode change request message to an owner of the NB; and   receiving an access mode change response message representing whether to allow an access mode change of the NB from the owner of the NB.   
     
     
         7 . The method of  claim 5 , further comprising:
 when determining to allow the access mode change of the NB, transmitting, to a User Equipment (UE), a system information modification message informing that system information has changed according to a changed access mode; and   transmitting, to the UE, a system information message including system information of the changed access mode.   
     
     
         8 . A method for changing an access mode by a Node B (NB) in a wireless communication system, the method comprising:
 determining to change the access mode of the NB;   transmitting, to a Core Network (CN), an access mode change request message that requests an access mode change of the NB; and   receiving, from the CN, an access mode change response message including an access mode control result.   
     
     
         9 . The method of  claim 8 , wherein the NB is a femto NB, further comprising:
 transmitting an access mode change request message to an owner of the NB; and   receiving an access mode change response message that indicates whether to allow the access mode change of the NB from the owner of the NB.   
     
     
         10 . The method of  claim 8 , further comprising:
 when the CN determines to allow the access mode change of the NB, transmitting, to a User Equipment (UE), a system information modification message informing that system information has changed according to a changed access mode; and   transmitting, to the UE, a system information message including system information of the changed access mode.   
     
     
         11 . The method of  claim 8 , wherein determining to change the access mode of the NB comprises:
 exchanging a load information message including cell load information with a plurality of NBs;   determining whether coverage areas of the NB and a neighbor NB overlap each other, whether a cell load of the neighbor NB is greater than a reference level, and whether a cell load of the NB is less than the reference level, based on load information for each cell collected through the load information message exchange, and an inter-NB coverage mapping table; and   when determining the coverage areas of the NB and the neighbor NB overlap each other, the cell load of the neighbor NB is greater than the reference level, and the cell load of the NB is less than the reference level, determining to change the access mode of the NB.   
     
     
         12 . A first Node B (NB) of a wireless communication system that changes an access mode of a second NB, the first NB comprising:
 a controller for determining to change the access mode of the second NB;   a transmission modem for transmitting, to the second NB, an access mode change request message requesting an access mode change of the second NB; and   a reception modem for receiving, from the second NB, an access mode change response message including an access mode control result.   
     
     
         13 . The first NB of  claim 12 , wherein the reception modem receives a measurement report message from a User Equipment (UE), and
 wherein the controller determines to change the access mode of the second NB when determining that the UE receives an interference of more than a reference level from the second NB, based on the measurement report message.   
     
     
         14 . The first NB of  claim 12 , wherein the reception modem receives load information messages including cell load information from a plurality of NBs, and
 wherein the controller determines to change the access mode of the second NB when determining that the coverage areas of the first NB and the second NB overlap each other, a cell load of the first NB is greater than a reference level, and a cell load of the second NB is less than the reference level, based on the load information for each cell collected through the reception of the load information message and an inter-NB coverage mapping table.   
     
     
         15 . A Node B (NB) of a wireless communication system that changes an access mode of the NB, the NB comprising:
 a reception modem for receiving, from another NB or a Core Network (CN), an access mode change request message requesting an access mode change of the NB;   a controller for controlling the access mode of the NB, when the access mode change request message is received, to determine whether to allow the access mode change of the NB; and   a transmission modem for transmitting, to the another NB or the CN, an access mode change response message including an access mode control result.   
     
     
         16 . The NB of  claim 15 , wherein when the NB is a femto NB, the transmission modem transmits an access mode change request message to an owner of the NB, and
 wherein the reception modem receives an access mode change response message indicating whether to allow the access mode change of the NB from the owner of the NB.   
     
     
         17 . The NB of  claim 15 , wherein when the controller determines to allow the access mode change of the NB, the transmission modem transmits, to a User Equipment (UE), a system information modification message informing that system information has changed according to a changed access mode, and transmits, to the UE, a system information message comprising system information of the changed access mode. 
     
     
         18 . A Node B (NB) of a wireless communication system that changes an access mode of the NB, the NB comprising:
 a controller for determining to change the access mode of the NB;   a transmission modem for transmitting an access mode change request message to a Core Network (CN), requesting an access mode change of the NB; and   a reception modem for receiving, from the CN, an access mode change response message including an access mode control result.   
     
     
         19 . The NB of  claim 18 , wherein when the NB is a femto NB, the transmission modem transmits an access mode change request message to an owner of the NB, and
 wherein the reception modem receives an access mode change response message representing whether to allow the access mode change of the NB from the owner of the NB.   
     
     
         20 . The NB of  claim 18 , wherein when the CN determines to allow the access mode change of the NB, the transmission modem transmits, to a User Equipment (UE), a system information modification message informing that system information has changed according to a changed access mode, and transmits, to the UE, a system information message including system information of the changed access mode. 
     
     
         21 . The NB of  claim 18 , wherein the reception modem receives load information messages including cell load information from a plurality of NBs, and
 wherein the controller determines to change the access mode of the NB when determining that coverage areas of the NB and a neighbor NB overlap each other, a cell load of the neighbor NB is greater than a reference level, and a cell load of the NB is less than a reference level, based on the load information for each cell collected through the reception of the load information messages and an inter-NB coverage mapping table.