Type-2 HARQ-ACK codebook for multi-cell scheduling DCI

1 . A processor of a user equipment (UE) configured to perform operations comprising:

receiving at least a first downlink control information (DCI) from a base station of a network, the first DCI scheduling multiple physical downlink shared channels (PDSCH) across multiple cells of the UE;

constructing a Type 2 hybrid automatic repeat request (HARQ) acknowledgement (HARQ-ACK) codebook, wherein the Type 2 HARQ-ACK codebook is constructed by adding a total number of HARQ-ACK bits for a first sub-codebook and a total number of HARQ-ACK bits for a second sub-codebook, wherein determining the total number of HARQ-ACK bits for the second sub-codebook is based on at least a parameter indicating a maximum number of serving cells for PDSCH when spatial bundling is enabled; and

transmitting Type 2 HARQ-ACK codebook feedback in a physical uplink channel.

2 . The processor of claim 1 , wherein the Type 2 HARQ-ACK codebook is further constructed based on whether HARQ-ACK bundling across cells is enabled for the UE.

3 . The processor of claim 1 , wherein the Type 2 HARQ-ACK codebook is constructed as a concatenation of the first sub-codebook and the second sub-codebook.

4 . The processor of claim 1 , wherein the first sub-codebook is constructed for DCI scheduling a single cell or PDSCH belonging to a same cell group for HARQ-ACK bundling and the second sub-codebook is constructed for DCI scheduling more than one cell or PDSCH belonging to more than one cell group for HARQ-ACK bundling.

5 . The processor of claim 4 , wherein a fixed number of HARQ-ACK bits are added to the first sub-codebook for each DCI scheduling a single cell or PDSCH corresponding to the Type 2 HARQ-ACK codebook.

6 . The processor of claim 1 , wherein a counter downlink assignment indicator (C-DAI) and a total DAI (T-DAI) are incremented independently for DCI corresponding to the respective first and second sub-codebooks.

7 . The processor of claim 6 , wherein, for each incremented DAI value, M bits are added to the second sub-codebook when HARQ-ACK spatial bundling is enabled and N bits are added to the second sub-codebook when a single transport block (TB) is configured per PDSCH without HARQ-ACK spatial bundling.

8 . The processor of claim 6 , wherein, for each incremented DAI value, N*2 bits are added to the second sub-codebook when two transport blocks (TB) are configured per PDSCH without HARQ-ACK spatial bundling.

9 . A user equipment (UE), comprising:

a transceiver configured to communicate with a base station of a network; and

a processor communicatively coupled to the transceiver and configured to perform operations comprising:

receiving at least a first downlink control information (DCI) from the base station of the network, the first DCI scheduling multiple physical downlink shared channels (PDSCH) across multiple cells of the UE;

constructing a Type 2 hybrid automatic repeat request (HARQ) acknowledgement (HARQ-ACK) codebook, wherein the Type 2 HARQ-ACK codebook is constructed by adding a total number of HARQ-ACK bits for a first sub-codebook and a total number of HARQ-ACK bits for a second sub-codebook, wherein determining the total number of HARQ-ACK bits for the second sub-codebook is based on at least a parameter indicating a maximum number serving cells for PDSCH when spatial bundling is enabled; and

transmitting Type 2 HARQ-ACK codebook feedback in a physical uplink channel.

10 . The UE of claim 9 , wherein the Type 2 HARQ-ACK codebook is further constructed based on whether HARQ-ACK bundling across cells is enabled for the UE.

11 . The UE of claim 9 , wherein the Type 2 HARQ-ACK codebook is constructed as a concatenation of the first sub-codebook and the second sub-codebook.

12 . The UE of claim 9 , wherein the first sub-codebook is constructed for DCI scheduling a single cell or PDSCH belonging to a same cell group for HARQ-ACK bundling and the second sub-codebook is constructed for DCI scheduling more than one cell or PDSCH belonging to more than one cell group for HARQ-ACK bundling.

13 . The UE of claim 12 , wherein a fixed number of HARQ-ACK bits are added to the first sub-codebook for each DCI scheduling a single cell or PDSCH corresponding to the Type 2 HARQ-ACK codebook.

14 . The UE of claim 9 , wherein a counter downlink assignment indicator (C-DAI) and a total DAI (T-DAI) are incremented independently for DCI corresponding to the respective first and second sub-codebooks.

15 . The UE of claim 14 , wherein, for each incremented DAI value, M bits are added to the second sub-codebook when HARQ-ACK spatial bundling is enabled and N bits are added to the second sub-codebook when a single transport block (TB) is configured per PDSCH without HARQ-ACK spatial bundling.

16 . The UE of claim 14 , wherein, for each incremented DAI value, N*2 bits are added to the second sub-codebook when two transport blocks (TB) are configured per PDSCH without HARQ-ACK spatial bundling.

17 . A processor of a base station configured to perform operations comprising:

transmitting at least a first downlink control information (DCI) to a user equipment (UE), the first DCI scheduling multiple physical downlink shared channels (PDSCH) across multiple cells of the UE;

receiving a Type 2 hybrid automatic repeat request (HARQ) acknowledgement (HARQ-ACK) codebook constructed by adding a total number of HARQ-ACK bits for a first sub-codebook and a total number of determined HARQ-ACK bits corresponding to a second sub-codebook, wherein determining the total number of HARQ-ACK bits for the second sub-codebook is based on at least a parameter indicating a maximum number serving cells for PDSCH when spatial bundling is enabled; and

processing a physical uplink channel according to a construction of the Type 2 HARQ-ACK codebook to determine HARQ-ACK feedback for the multiple PDSCH.