Method and apparatus for supporting discontinuous reception operation in mobile communication system

Abstract

A method and an apparatus for supporting a discontinuous reception (DRX) operation in a Node B in a mobile communication system are provided. The method includes defining a second System Frame Number (SFN) where one cycle of a first SFN corresponds to one bit, transmitting information on the second SFN to a User Equipment (UE), determining a second SFN which is used to transmit a paging signal to the UE, determining a first SFN which is used to transmit the paging signal in the determined second SFN, and transmitting the paging signal to the UE at the determined first SFN.

The invention claimed is: 
     
       1. A method for supporting a Discontinuous Reception discontinuous reception (DRX) operation in by a Node B in a mobile wireless communication system, the method comprising:
 defining a second System Frame Number (SFN) where one cycle of a first SFN corresponds to one bit; 
 determining a first system frame number (SFN) for a user equipment (UE) based on an identifier of the UE;  
 transmitting information on the a second SFN to a User Equipment (UE) for the UE which is configured with an extended DRX, the second SFN being incremented by one when one cycle of the first SFN wraps around; 
 determining a second SFN which is used to transmit a paging signal to the UE, based on the information on the second SFN; 
 determining a paging occasion based on a first SFN which is used to transmit the paging signal in the determined second SFN with a cycle longer than a cycle of the first SFN; and 
 transmitting, to the UE, the paging signal to the UE at in the determined first SFN paging occasion. 
 
     
     
       2. The method of  claim 1 , wherein the determined second SFN satisfies “(T M  div N m  N M )*(UE_ID mod N M )” and the determined first SFN satisfies “(T div N)*(UE_ID mod N)”, and
 wherein the N M  is min (T M , nB M ), the “N” is min (T, nB), the T M , nB M , T, and nB are DRX cycles of the UE, and the UE_ID is the identifier of the UE which is determined based on an International Mobile Station Identity (IMSI). 
 
     
     
       3. The method of  claim 1 , wherein the second SFN is added to one of a Master Information Block master information block (MIB), an existing System Information Block system information block (SIB), and a new SIB, and is then transmitted to the UE. 
     
     
       4. The method of  claim 1 , wherein the UE corresponds to is a machine-type communication device. 
     
     
       5. An apparatus A Node B for supporting a Discontinuous Reception discontinuous reception (DRX) operation in a Node B in a mobile wireless communication system, the apparatus Node B comprising:
 a transceiver for defining a second System Frame Number (SFN) where one cycle of a first SFN corresponds to one bit, and for transmitting information on the second SFN to a User Equipment (UE); and 
 a controller for coupled with the transceiver and configured to control to:
 determine a first system frame number (SFN) for a user equipment (UE) based on an identifier of the UE, 
 transmit information on a second SFN for a UE which is configured with an extended DRX, the second SFN being incremented by one when one cycle of the first SFN wraps around, 
 determiningdetermine a second SFN which is used to transmit a paging signal to the UE, based on the information on the second SFN,  
 for determiningdetermine a paging occasion based on a first SFN, which is used to transmit the paging signal in the determined second SFN with a cycle longer than a cycle of the first SFN, and 
 for controlling the transceiver to transmit, to the UE, the paging signal to the UE at in the determined first SFN paging occasion. 
 
 
     
     
       6. The apparatus Node B of  claim 5 , wherein the determined second SFN satisfies “(T M  div N m  N M )*(UE_ID mod N M )” and the determined first SFN satisfies “(T div N)*(UE_ID mod N)”, and
 wherein the N M  is min (T M , nB M ), the “N” is min (T, nB), the T M , nB M , T, and nB are DRX cycles of the UE, and UE_ID is determined based on an International Mobile Station Identity (IMSI). 
 
     
     
       7. The apparatus Node B of  claim 5 , wherein the second SFN is added to one of a Master Information Block master information block (MIB), an existing System Information Block system information block (SIB), and a new SIB, and is then transmitted to the UE. 
     
     
       8. The apparatus Node B of  claim 5 , wherein the UE corresponds to is a machine-type communication device. 
     
     
       9. A method for supporting a Discontinuous Reception discontinuous reception (DRX) operation in by a User Equipment user equipment (UE) in a mobile wireless communication system, the method comprising:
 determining a first system frame number (SFN) for the UE based on an identifier of the UE; 
 receiving, from a Node B, information on a second System Frame Number (SFN), where one cycle of a first SFN corresponds to one bit SFN for the UE which is configured with an extended DRX, the second SFN being incremented by one when one cycle of the first SFN wraps around; 
 monitoring the first SFN and the second SFN every cycle of the first SFN; 
 determining whether the second SFN includes a paging signal; 
 determining whether the first SFN corresponding to the second SFN includes the paging signal when the second SFN includes the paging signal; and 
 identifying the paging signal through the first SFN when the first SFN includes the paging signal 
 determining a second SFN which is used to transmit a paging signal to the UE, based on the information on the second SFN; 
 determining a paging occasion based on a first SFN which is used to transmit the paging signal in the determined second SFN with a cycle longer than a cycle of the first SFN; and 
 monitoring whether the paging signal is received in the determined paging occasion. 
 
     
     
       10. The method of  claim 9 , wherein a case in which the second SFN includes the paging signal corresponds to a case in which the second SFN satisfies “(T M  div NM)*(UE_ID mod N M )” and a case in which the first SFN includes the paging signal corresponds to a case in which the first SFN satisfies “(T div N)*(UE_ID mod N)”,
 wherein the N M  is min (T M , nB M ), the “N” is min (T, nB), the T M , nB M , T, and nB are DRX cycles of the UE, and the UE_ID is the identifier of the UE which is determined based on an International Mobile Station Identity (IMSI). 
 
     
     
       11. The method of  claim 9 , wherein the second SFN is added to one of a Master Information Block master information block (MIB), an existing System Information Block system information block (SIB), and a new SIB, and is then transmitted to the UE. 
     
     
       12. The method of  claim 9 , wherein the UE corresponds to is a machine-type communication device. 
     
     
       13. An apparatus A user equipment (UE) for supporting a Discontinuous Reception discontinuous reception (DRX) operation in a User Equipment (UE) in a mobile wireless communication system, the apparatus UE comprising:
 a transceiver for receiving, from a Node B, information on a second System Frame Number (SFN), where one cycle of a first SFN corresponds to one bit; and 
 a controller for coupled with the transceiver and configured to control to:
 determine a first system frame number (SFN) for the UE based on an identifier of the UE, 
 receive, from a Node B, information on a second SFN for the UE which is configured with an extended DRX, the second SFN being incremented by one when one cycle of the first SFN wraps around, 
 determine a second SFN which is used to transmit a paging signal to the UE, based on the information on the second SFN, 
 determine a paging occasion based on a first SFN which is used to transmit the paging signal in the determined second SFN with a cycle longer than a cycle of the first SFN, and  
 monitoring the first SFN and the second SFN every cycle of the first SFN, for determining whether the second SFN includes a paging signal, for determining whether the first SFN corresponding to the second SFN includes the paging signal when the second SFN includes the paging signal, and for identifying the paging signal through the first SFN when the first SFN includes the paging signalmonitor whether the paging signal is received in the paging occasion. 
 
 
     
     
       14. The apparatus UE of  claim 13 , wherein the second SFN is added to one of a Master Information Block master information block (MIB), an existing System Information Block system information block (SIB), and a new SIB, and is then transmitted to the UE. 
     
     
       15. The apparatus UE of  claim 13 , wherein a case in which the second SFN includes the paging signal corresponds to a case in which the second SFN satisfies “(T M  div NM)*(UE_ID mod N M )” and a case in which the first SFN includes the paging signal corresponds to a case in which the first SFN satisfies “(T div N)*(UE_ID mod N)”,
 wherein the N M  is min (T M , nB M ), the “N” is min (T, nB), the T M , nB M , T, and nB are DRX cycles of the UE, and the UE_ID is the identifier of the UE which is determined based on an International Mobile Station Identity (IMSI). 
 
     
     
       16. The apparatus UE of  claim 13 , wherein the UE corresponds to is a machine-type communication device. 
     
     
       17. A method for supporting a Discontinuous Reception (DRX) operation in a User Equipment (UE) in a mobile communication system, the method comprising:
 receiving system information which includes a cell-specific DRX cycle from a Node B;   transmitting an attach request message, which includes a UE-specific DRX cycle and an indication for selecting a DRX cycle of a long cycle, to a Mobility Management Entity (MME);   selecting a longer cycle of the cell-specific DRX cycle and the UE-specific DRX cycle when receiving an attach response message from the MME; and   receiving a paging message from the Node B in the selected DRX cycle.   
     
     
       18. An apparatus for supporting a Discontinuous Reception (DRX) operation in a User Equipment (UE) in a mobile communication system, the apparatus comprising:
 a transceiver for receiving system information which includes a cell-specific DRX cycle from a Node B, and for transmitting an attach request message to a Mobility Management Entity (MME), the attach request message including a UE-specific DRX cycle and an indication for selecting a DRX cycle of a long cycle; and   a controller for selecting a longer cycle of the cell-specific DRX cycle and the UE-specific DRX cycle when receiving an attach response message from the MME; and for controlling the transceiver to receive a paging message from the Node B in the selected DRX cycle.   
     
     
       19. A method for supporting a Discontinuous Reception (DRX) operation in a Node B in a mobile communication system, the method comprising:
 transmitting system information which includes a cell-specific DRX cycle to a User Equipment (UE);   receiving a UE-specific DRX cycle and an indication for selecting a DRX cycle of a long cycle from a Mobility Management Entity (MME);   selecting a longer cycle of the cell-specific DRX cycle and the UE-specific DRX cycle; and   transmitting a paging message to the UE in the selected DRX cycle.   
     
     
       20. An apparatus for supporting a Discontinuous Reception (DRX) operation in a Node B in a mobile communication system, the apparatus comprising:
 a transceiver for transmitting system information which includes a cell-specific DRX cycle to a User Equipment (UE), and for receiving a UE-specific DRX cycle and an indication for selecting a DRX cycle of a long cycle from a Mobility Management Entity (MME); and   a controller for selecting a longer cycle of the cell-specific DRX cycle and the UE-specific DRX cycle, and for controlling the transceiver to transmit a paging message to the UE in the selected DRX cycle.   
     
     
       21. A method for supporting a Discontinuous Reception (DRX) operation in a User Equipment (UE) in a mobile communication system, the method comprising:
 determining whether a cell on which the UE is currently camping corresponds to a cell supporting a DRX cycle of a long cycle;   selecting a longer DRX cycle of a cell-specific DRX cycle and a UE-specific DRX cycle when the cell on which the UE is currently camping supports the DRX cycle of a long cycle; and   receiving a paging message from a Node B of the cell, on which the UE is camping, in the selected DRX cycle.   
     
     
       22. The method as claimed in  claim 21 , further comprising: selecting a shorter DRX cycle of a cell-specific DRX cycle and a UE-specific DRX cycle when the cell on which the UE is currently camping does not support the DRX cycle of a long cycle. 
     
     
       23. An apparatus for supporting a Discontinuous Reception (DRX) operation in a User Equipment (UE) in a mobile communication system, the apparatus comprising:
 a controller for determining whether a cell on which the UE is currently camping corresponds to a cell supporting a DRX cycle of a long cycle, and for selecting a longer DRX cycle of a cell-specific DRX cycle and a UE-specific DRX cycle when the cell on which the UE is currently camping supports the DRX cycle of a long cycle; and   a transceiver for receiving a paging message from a Node B of the cell, on which the UE is camping, in the selected DRX cycle.   
     
     
       24. The apparatus as claimed in  claim 23 , wherein, when the cell on which the UE is currently camping does not support the DRX cycle of a long cycle, the controller selects a shorter DRX cycle of a cell-specific DRX cycle and a UE-specific DRX cycle. 
     
     
       25. A method for supporting a Discontinuous Reception (DRX) operation in a Mobility Management Entity (MME) in a mobile communication system, the method comprising:
 receiving a request for a DRX cycle of a long cycle from a User Equipment (UE);   determining whether a cell on which the UE is camping supports a DRX cycle of a long cycle; and   transmitting a paging message to a Node B of the cell, on which the UE is camping, in a UE-specific DRX cycle when the cell on which the UE is camping supports a DRX cycle of a long cycle.   
     
     
       26. The method as claimed in  claim 25 , further comprising: transmitting the paging message to the Node B of the cell, on which the UE is camping, in a predetermined cycle when the cell on which the UE is camping does not support a DRX cycle of a long cycle. 
     
     
       27. An apparatus for supporting a Discontinuous Reception (DRX) operation in a Mobility Management Entity (MME) in a mobile communication system, the apparatus comprising:
 a transceiver for receiving a request for a DRX cycle of a long cycle from a User Equipment (UE); and   a controller for determining whether a cell on which the UE is camping supports a DRX cycle of a long cycle, and for controlling the transceiver to transmit a paging message to a Node B of the cell, on which the UE is camping, in a UE-specific DRX cycle when the cell on which the UE is camping supports a DRX cycle of a long cycle.   
     
     
       28. The apparatus as claimed in  claim 27 , wherein, when the cell on which the UE is camping does not support a DRX cycle of a long cycle, the controller controls the transceiver to transmit the paging message the Node B of the cell, on which the UE is camping, in a predetermined cycle. 
     
     
       29. The method of claim 1, wherein the second SFN which is used to transmit the paging signal to the UE, is determined using the information and identification information of the UE. 
     
     
       30. The Node B of claim 5, wherein the second SFN which is used to transmit the paging signal to the UE, is determined using the information and identification information of the UE. 
     
     
       31. The method of claim 9, wherein the second SFN which is used to transmit the paging signal to the UE, is determined using the information and identification information of the UE. 
     
     
       32. The UE of claim 13, wherein the second SFN which is used to transmit the paging signal to the UE, is determined using the information and identification information of the UE.