Patent ID: 8885526

Claim:
An apparatus comprising: transceiver module configured to communicate via a plurality of serving cells, wherein at least two of the serving cells have different time division duplexing (TDD) uplink-downlink (UL-DL) configurations; and a feedback controller coupled with the transceiver module and configured to: obtain a downlink assignment index (DAI); determine a number of downlink subframes within a bundling window of a first serving cell of the plurality of serving cells, wherein the downlink subframes of the bundling window are associated with an uplink subframe for transmission of corresponding hybrid automatic repeat request-acknowledgment (HARQ-ACK) information; determine a number of HARQ-ACK bits, which corresponds to the first serving cell, available on a physical uplink shared channel (PUSCH) of the uplink subframe based on the DAI and the determined number of downlink subframes; determine a value that corresponds to the DAI; select whichever of the determined value or the determined number of downlink subframes is smaller as the number of HARQ-ACK bits for the first serving cell; and determine a HARQ-ACK codebook size on the PUSCH of the uplink subframe based on the number of HARQ-ACK bits for the first serving cell.