Method and apparatus for selecting a radio link control protocol data unit size

摘要

A method and apparatus are used to create RLC PDUs in advance of the E-TFC selection for the MAC PDU that will include this or these RLC PDU(s). The apparatus may be configured to pre-generate RLC PDUs for transmission in a later TTI. This approach avoids the large peak processing requirement due to the tight delay constraint if any RLC PDU to be included into a MAC PDU had to be created after the determination of the size of this MAC PDU, i.e. after E-TFC selection. The method and apparatus maintain an approximate match between the size of an RLC PDU and the size of the MAC PDU it is included into. Maintaining this approximate match ensures that the RLC PDU error rate due to HARQ residual errors remains low. This approach may be designed as “semi-radio aware” or “radio-aware with delay”.

主权项

1. A method for use in a wireless transmit/receive unit (WTRU) for generating a radio link control (RLC) protocol data unit (PDU), the method comprising:
determining whether there is data available for transmission; on a condition that a total amount of data in outstanding RLC PDUs that are pre-generated for transmission in a later transmission time interval (TTI) is within a predetermined limit, pre-generating an RLC PDU for transmission in the later TTI, wherein the predetermined limit corresponds to a factor multiplied by a maximum amount of data for transmission allowed by a current grant for a current TTI; and setting a size of a data field in the RLC PDU, wherein the size of the data field is determined such that an RLC PDU size matches an amount of data allowed for transmission by the current grant for the current TTI.