HARQ Feedback for Multiple Uplink Codeword Transmission

The patent segments the HARQ feedback mechanism by introducing separate HARQ processes for each uplink codeword. When multiple codewords are transmitted, the receiver generates individual HARQ ACK/NACK signals for each codeword, allowing independent acknowledgment and retransmission control. This segmentation enables the system to handle multiple codewords efficiently without overwhelming complexity, as each codewor d can be managed through its own HARQ process while still benefiting from the overall multiple-antenna transmission capability.

The patent merges multiple HARQ feedback signals into a unified feedback mechanism. When multiple uplink codewords are transmitted, instead of sending completely separate feedback channels for each codeword, the system combines the HARQ ACK/NACK information for multiple codewords into a single feedback transmission. This merging approach maintains the accuracy of individual codeword acknowledgment while reducing the overall control information overhead by consolidating the feedback resources.

The patent introduces dynamic layer mapping adjustment for retransmission. When a codeword requires retransmission, the system dynamically swaps the layer mapping configuration, assigning the retransmitted codeword to a different layer than the original transmission. This dynamic adjustment exploits the spatial diversity provided by multiple antennas, improving the probability that the retransmitted signal will be successfully decoded by selecting a layer with better channel conditions. The processing complexity increase is managed through predetermined swapping rules that reduce the computational burden of determining the new layer assignment.