System and method for applying extended accessing barring in wireless communication system

Abstract

A system and a method that employs Extended Access Barring (EAB) when a Machine Type Communication (MTC) device performs an attempt to access an evolved Node B (eNB) in a wireless communication system are provided. When User Equipment (UE) supporting MTC, an MTC device, performs an attempt to access a network, the system and method determines whether it can access the network and performs the access procedure. The system and method can control the operations of UE that performs an attempt to access a network, thereby preventing excessive access.

What is claimed is: 
     
       1. A method by a user equipment (UE) in a wireless communication system, the method comprising:
 requesting, by a first layer of the UE, a second layer of the UE to establish a radio resource control (RRC) connection; and 
 identifying, if the UE receives receiving, by the UE, an extended access barring (EAB) parameter, 
 identifying whether an EABaccess barring is applied to a request for the RRC connection,based on the received access barring parameter; and 
 when the access barring is not applied to the request for the RRC connection:
 transmitting a first random access preamble to a base station, if the EAB is not applied to the request for the RRC connection; 
 receiving a random access response including a first type backoff and a second type backoff; and backoff information, 
 determining a backoff value based on the backoff information and a scaling factor, and 
 transmitting a second random access preamble based on one of the first type backoff and the second type backoff the backoff value. 
 
 
     
     
       2. The method of  claim 1 , further comprising:
 checking, by the second layer of the UE, if when the first layer of the UE indicates that the EAB access barring is applied to the request for the RRC connection, whether access to a cell is barred by the EAB access barring; and 
 informing, by the second layer of the UE, if when the access to the cell is barred by the EAB access barring, of a failure of the RRC connection to the first layer of the UE. 
 
     
     
       3. The method of  claim 2 , wherein the checking of whether access to the cell is barred by the EAB access barring comprises:
 if the UE belongs to a category of UEs as indicated in an EAB Category contained in the EAB parameter and if an AC of the UE belongs to a range excluding the ACs 11 to 15, considering access to a cell as barredin case that an access attempt corresponding to the RRC connection is for a mobile terminating (MT) access, considering the access attempts as allowed. 
 
     
     
       4. The method of  claim 1 , further comprising:
 performing, if a system information block received from the base station includes an AC barring parameter for the ACB, an access barring check 
 receiving, from the base station, a system information block including an access class barring parameter, 
 wherein the identifying of whether the access barring is applied to the request for the RRC connection is based on the access class barring parameter included in the system information block. 
 
     
     
       5. The method of  claim 4 , wherein the performing of the Access barring check comprises the method further comprising:
 considering, if the UE has one or more ACs with a value in a first range, which is valid for the UE, access to a cell as not barred; 
 generating, if the UE does not have the one or more ACs with the value in the first range, a random number uniformly distributed in the range of 0 to 1; 
 considering, ifidentifying, when the random number is lower than a value indicated by the ACaccess class barring parameter, the access to the cell as not barredattempt as allowed; and 
 considering, ifidentifying, when the random number is not lower than the value indicated by the ACaccess class barring parameter, the access to the cellattempt as barred. 
 
     
     
       6. A user equipment (UE) in a wireless communication system, the UE comprising:
 a transceiver configured to transmit and receive signals; and 
 aat least one processorconfigured to:; 
 a memory storing instructions, wherein the instructions, when executed by the at least one processor, cause the at least one processor to control to:
 request, by a first layer of the UE,identify a request for a second layer of the UE to establish a radio resource control (RRC) connection, 
 identify, if in case that the UE receives an extended access barring (EAB) parameter, whether an EAB access barring is applied to a request for the RRC connectionexcept, and 
 in case that the access barring is not applied to the request for the RRC connection: 
 transmit a first random access preamble to a base station, if the EAB is not applied to the request for the RRC connection, 
 receive a random access response including a first type backoff and a second type backoff backoff information, and 
 determine a backoff value based on the backoff information and a scaling factor, and  
 transmit a second random access preamble based on one of the first type backoff and the second type backoff the backoff value. 
 
 
 
     
     
       7. The UE of  claim 6 , wherein the processor is further configured to instructions, when executed by the at least one processor, cause the at least one processor to further control to:
 check, if in case that the first layer of the UE indicates that the EAB access barring is applied to the request for the RRC connection, whether access to a cell is barred by the EAB access barring, and 
 inform, if in case that the access to a cell is barred by the EAB access barring, of a failure of the RRC connection to the first layer of the UE. 
 
     
     
       8. The UE of  claim 7 , wherein the processor is further configured to instructions, when executed by the at least one processor, cause the at least one processor to further control to considerif the UE belongs to a category of UEs as indicated in an EAB Category contained in the EAB parameter and if an AC of the UE belongs to a range excluding the ACs 11 to 15, access to a cell as barred, in case that an access attempt corresponding to the RRC connection is for a mobile terminating (MT) access, the access attempts as allowed. 
     
     
       9. The UE of  claim 6 , wherein the processor is further configured to perform, if a system information block received from the base station includes an AC barring parameter for the ACB, an access barring check instructions, when executed by the at least one processor, cause the at least one processor to further control to:
 receive, from the base station, a system information block including an access class barring parameter, 
 wherein the identifying of whether the access barring is applied to the request for the RRC connection is based on the access class barring parameter included in the system information block. 
 
     
     
       10. The UE of  claim 9 , wherein the processor is further configured to: instructions, when executed by the at least one processor, cause the at least one processor to further control to:
 consider, if the UE has one or more ACs with a value in a first range, which is valid for the UE, access to a cell as not barred, 
 generate, if the UE does not have the one or more ACs with the value in the first range, a random number uniformly distributed in the range of 0 to 1, 
 consider, ifidentify, in case that the random number is lower than a value indicated by the ACaccess class barring parameter, the access to the cell as not barredattempt as allowed, and 
 consider, ifidentify, in case that the random number is not lower than the value indicated by the ACaccess class barring parameter, the access to the cellattempt as barred.