Method and apparatus for generating radio link control protocol data units

Abstract

A method and apparatus are used to generate radio link control (RLC) protocol data units (PDUs). A data request for a logical channel is received as part of an enhanced dedicated channel (E-DCH) transport format combination (E-TFC) selection procedure in a medium access control (MAC). Upon determining the data field size, an RLC PDU is generated such that it matches the requested data from the E-TFC selection. The size of the RLC PDU generated can be greater than or equal to the minimum configured RLC PDU size (if data is available) and less than or equal to the maximum RLC PDU size. The data is then transmitted in the RLC PDU in a current transmission time interval (TTI).

What is claimed is: 
     
         1 . A method comprising:
 determining a data field size for a radio link control (RLC) protocol data unit (PDU) based on a current enhanced dedicated channel (E-DCH) transport format combination (E-TFC) selection, a minimum RLC PDU size and an amount of data to be transmitted; and   generating the RLC PDU based on the determined data field size.   
     
     
         2 . The method of  claim 1 , wherein the data field size for the RLC PDU is determined such that an RLC PDU size of the RLC PDU matches data requested for a logical channel by the E-TFC selection. 
     
     
         3 . The method of  claim 1 , wherein the data field size for the RLC PDU is determined such that an RLC PDU size of the RLC PDU is less than the minimum RLC PDU size when the data to be transmitted is insufficient to create an RLC PDU of the minimum RLC PDU size. 
     
     
         4 . The method of  claim 1 , wherein the data field size for the RLC PDU is determined such that an RLC PDU size of the RLC PDU is greater than or equal to the minimum RLC PDU size when the data to be transmitted is sufficient to create an RLC PDU of the minimum RLC PDU size or greater. 
     
     
         5 . The method of  claim 1  further comprising:
 sending the RLC PDU in a current transmission time interval. 
 
     
     
         6 . The method of  claim 1  further comprising:
 receiving an indication of the minimum RLC PDU size via radio resource control signaling. 
 
     
     
         7 . The method of  claim 1 , wherein the data field size for the RLC PDU is determined such that an RLC PDU size accounts for an addition of a media access control (MAC) header to be added by a MAC entity when the RLC PDU is generated. 
     
     
         8 . A wireless transmit/receive unit (WTRU) comprising:
 a processor configured to:
 determine a data field size for a radio link control (RLC) protocol data unit (PDU) based on a current enhanced dedicated channel (E-DCH) transport format combination (E-TFC) selection, a minimum RLC PDU size and an amount of data to be transmitted; and 
 generate the RLC PDU based on the determined data field size. 
   
     
     
         9 . The WTRU of  claim 8 , wherein the data field size for the RLC PDU is determined such that an RLC PDU size of the RLC PDU matches data requested for a logical channel by the E-TFC selection. 
     
     
         10 . The WTRU of  claim 8 , wherein the data field size for the RLC PDU is determined such that an RLC PDU size of the RLC PDU is less than the minimum RLC PDU size when the data to be transmitted is insufficient to create an RLC PDU of the minimum RLC PDU size. 
     
     
         11 . The WTRU of  claim 8 , wherein the data field size for the RLC PDU is determined such that an RLC PDU size of the RLC PDU is greater than or equal to the minimum RLC PDU size when the data to be transmitted is sufficient to create an RLC PDU of the minimum RLC PDU size or greater. 
     
     
         12 . The WTRU of  claim 8 , wherein the processor is configured to:
 send the RLC PDU in a current transmission time interval.   
     
     
         13 . The WTRU of  claim 8 , wherein the processor is configured to:
 receive an indication of the minimum RLC PDU size via radio resource control signaling.   
     
     
         14 . The WTRU of  claim 8 , wherein the data field size for the RLC PDU is determined such that an RLC PDU size accounts for an addition of a media access control (MAC) header to be added by a MAC entity when the RLC PDU is generated. 
     
     
         15 . A wireless transmit/receive unit (WTRU) comprising:
 a processor configured to:
 determine a data field size for a radio link control (RLC) protocol data unit (PDU), the determining comprising:
 setting an available requested data size to match a data request from an enhanced dedicated channel (E-DCH) transport format combination (E-TFC) selection procedure when there is data for transmission, 
 on a condition that the available requested data size is greater than or equal to a minimum RLC PDU size, determining the data field size such that an RLC PDU size of the RLC PDU corresponds to a minimum of: the available requested data size, an available data size and a maximum RLC PDU size, and 
 on a condition that the available requested data size is determined to be less than the minimum RLC PDU size, determining the data field size such that the RLC PDU size of the RLC PDU corresponds to a minimum of: the available data size and the minimum RLC PDU size; and 
 
 generate the RLC PDU based on the determined data field size. 
   
     
     
         16 . The WTRU of  claim 15 , wherein the processor is further configured to:
 subtract a media access control (MAC) header size value from the available requested data size when generating at least one RLC PDU.   
     
     
         17 . The WTRU of  claim 15 , wherein the processor is further configured to:
 subtract a media access control (MAC) header size value from the available requested data size prior to generating at least one RLC PDU.   
     
     
         18 . The WTRU of  claim 15 , wherein the processor is further configured to:
 perform a data retransmission, wherein the data retransmission is transmitted as at least one full RLC PDU; and   decrease the available requested data size by a size of the retransmitted RLC PDU.   
     
     
         19 . The WTRU of  claim 18 , wherein the processor is further configured to:
 subtract a media access control (MAC) header size value from the available requested data size when retransmitting an RLC PDU.   
     
     
         20 . The WTRU of  claim 18 , wherein the processor is further configured to:
 subtract a media access control (MAC) header size value multiplied by the number of retransmitted RLC PDUs when decreasing the available requested data size.