Patent ID: 9705655
Date: 2017-07-11
CPC Classifications: H04L

Claim:
1. A method of determining a number of Acknowledgment/Non-Acknowledgment (ACK/NACK) feedback bits, wherein when carriers with different Time Division Duplex (TDD) uplink/downlink configurations are aggregated for a User Equipment (UE) or aggregated carriers comprise at least one Frequency Division Duplex (FDD) carrier and at least one TDD carrier, and if the UE feeds back ACK/NACK over a Physical Uplink Shared Channel (PUSCH) with a corresponding Physical Downlink Control Channel (PDCCH), the PDCCH including a Downlink Assignment Index (DAI) field, the method comprising: determining presence of a first carrier among carriers undergoing carrier aggregation for a UE, that has a reference TDD uplink/downlink configuration that indicates a set of indexes K: {k applying, responsive to determining that the first carrier is present among the carriers undergoing carrier aggregation, a first category of scheme to determine the number of downlink sub-frames, on each carrier c aggregated for the UE, for which ACK/NACK is to be fed back in a current uplink sub-frame; responsive to determining that the first carrier is not present among the carriers undergoing carrier aggregation, obtaining W determining the number of ACK/NACK feedback bits to be fed back in the current uplink sub-frame according to the determined number of downlink sub-frames on each carrier c for which ACK/NACK is to be fed back in the current uplink sub-frame; wherein W M