Transmitting and receiving a pdcp layer status report in a mobile telecommunications system

Abstract

A PDCP status report can be transmitted with reduced radio resources by transmitting the reception success or failure of a series of PDCP service data units (SDUs) in the form of a bitmap when configuring the PDCP status report. A PDCP control packet data unit (PDU) is generated to communicate a status report to a transmitting node for one or more PDCP SDUs transmitted from the transmitting node. The PDCP control PDU includes a data/control (D/C) bit field to indicate the PDCP control PDU is a control PDU, a control PDU type field to indicate a type of corresponding control information, a sequence number field to indicate a first missing PDCP SDU, and a bitmap field for a variable length bitmap. A bit in the variable length bitmap indicates whether a corresponding one of the one or more PDCP SDUs has been successfully been received.

1 . (canceled) 
     
     
         2 . A method for transmitting a status report in a packet data convergence protocol (PDCP) layer in a mobile communication system, the method comprising:
 generating, by a first transceiver, a PDCP control packet data unit (PDU) to communicate a status report for one or more PDCP service data units (SDUs) transmitted from a second transceiver,   wherein the PDCP control PDU includes:
 a data/control (D/C) bit field that indicates the PDCP control PDU is a control PDU, 
 a control PDU type field that indicates a type of corresponding control information, 
 a sequence number field to indicate a first missing PDCP SDU, and 
 a bitmap field for a variable length bitmap, and 
   wherein a specific bit in the variable length bitmap indicates whether a corresponding one of the one or more PDCP SDUs has been successfully been received at the first transceiver, and   transmitting, by the first transceiver, the PDCP control PDU to the second transceiver.   
     
     
         3 . The method in  claim 2 , wherein the first transceiver is a user equipment (UE) and the second transceiver station is an evolved NodeB (eNB). 
     
     
         4 . The method in  claim 2 , wherein the first transceiver is an evolved NodeB (eNB) and the second transceiver is a user equipment (UE). 
     
     
         5 . The method of  claim 2 , wherein the specific bit in the variable length bitmap is configured with a single bit. 
     
     
         6 . The method of  claim 5 , wherein the single bit is set to 0 or 1 to indicate whether a corresponding one of the one or more PDCP SDUs has been received successfully at the first transceiver during a handover operation. 
     
     
         7 . The method of  claim 6 , wherein the single bit is set to  0  when the corresponding one of the one or more PDCP SDUs has not been received successfully at the first transceiver during the handover operation, and
 wherein the single bit is set to 1 when the corresponding one of the one or more PDCP SDUs does not need to be retransmitted. 
 
     
     
         8 . The method of  claim 2 , wherein a length of the variable length bitmap can be 0. 
     
     
         9 . The method of  claim 2 , wherein the control PDU type field indicates a PDCP status report. 
     
     
         10 . Apparatus for transmitting a status report in a packet data convergence protocol (PDCP) layer in a mobile communication system, the apparatus comprising:
 processing circuitry configured to generate a PDCP control packet data unit (PDU) to communicate a status report for one or more PDCP service data units (SDUs) transmitted from a second transceiver,   wherein the PDCP control PDU includes:
 a data/control (D/C) bit field that indicates the PDCP control PDU is a control PDU, 
 a control PDU type field that indicates a corresponding control information, 
 a sequence number field to indicate a first missing PDCP SDU, and 
 a bitmap field for a variable length bitmap, and 
   wherein a specific bit in the variable length bitmap indicates whether a corresponding one of the one or more PDCP SDUs has been successfully been received at the first transceiver, and   a transmitter configured to transmit the PDCP control PDU to the second transceiver.   
     
     
         11 . The apparatus in  claim 10 , wherein the first transceiver is a user equipment (UE) and the second transceiver is an evolved NodeB (eNB). 
     
     
         12 . The apparatus in  claim 10 , wherein the first transceiver is an evolved NodeB (eNB) and the second transceiver is a user equipment (UE). 
     
     
         13 . The apparatus in  claim 10 , wherein the specific bit in the variable length bitmap is configured with a single bit, and
 wherein the single bit is set to 0 or 1 to indicate whether a corresponding one of the one or more PDCP SDUs has been received successfully at the first transceiver during a handover operation.   
     
     
         14 . The apparatus in  claim 13 , wherein the single bit is set to 0 when the corresponding one of the one or more PDCP SDUs has not been received successfully at the first transceiver during the handover operation, and
 wherein the single bit is set to 1 when the corresponding one of the one or more PDCP SDUs does not need to be retransmitted.   
     
     
         15 . The apparatus in  claim 10 , wherein a length of the variable length bitmap can be 0. 
     
     
         16 . The apparatus in  claim 10 , wherein the control PDU type field indicates a PDCP status report. 
     
     
         17 . Apparatus for transmitting a status report in a packet data convergence protocol (PDCP) layer in a mobile communication system, the apparatus comprising:
 at least one processor;   at least one memory including computer program code, the memory and the computer program code configured to, working with the at least one processor, cause the apparatus to:   generate a PDCP control packet data unit (PDU) to communicate a status report for one or more PDCP service data units (SDUs) transmitted from a second transceiver,   wherein the PDCP control PDU includes:
 a data/control (D/C) bit field that indicates the PDCP control PDU is a control PDU, 
 a control PDU type field that indicates a type of corresponding control information, 
 a sequence number field to indicate a first missing PDCP SDU, and 
 a bitmap field for a variable length bitmap, and 
   wherein a specific bit in the variable length bitmap indicates whether a corresponding one of the one or more PDCP SDUs has been successfully been received at the first transceiver, and   control a transmitter to transmit the PDCP control PDU to the second transceiver.   
     
     
         18 . The apparatus in  claim 17 , wherein the first transceiver is a user equipment (UE) and the second transceiver is an evolved NodeB (eNB). 
     
     
         19 . The apparatus in  claim 17 , wherein the first transceiver is an evolved NodeB (eNB) and the second transceiver is a user equipment (UE). 
     
     
         20 . The apparatus in  claim 17 , wherein the control PDU type field indicates a PDCP status report.