Hybrid automatic repeat request feedback control by base station

1. A method comprising:

transmitting, to a wireless device, radio resource control (RRC) messages comprising parameters of a multicast and broadcast service (MBS),

wherein the parameters indicate:

a first feedback operation with hybrid automatic repeat request (HARQ) feedback being enabled; and

a second feedback operation with the HARQ feedback being disabled; and

wherein a group common downlink control information (DCI) indicates one of the first feedback operation or the second feedback operation;

transmitting a first group common DCI:

scheduling a first transport block (TB) of the MBS; and

indicating the first feedback operation; and

receiving, based on the first group common DCI indicating the first feedback operation, a first HARQ feedback for the first TB.

2. The method of claim 1 , wherein the first HARQ feedback for the first TB comprises:

a positive feedback in response to the first TB being successfully decoded; and

a negative feedback in response to the first TB being unsuccessfully decoded.

3. The method of claim 1 , wherein the second feedback operation, with the HARQ feedback being disabled, comprises skipping a transmission of the first HARQ feedback for the first TB regardless of whether the first TB is decoded successfully.

4. The method of claim 1 , wherein the first group common DCI comprises a HARQ feedback enabling/disabling indication field indicating the first feedback operation.

5. The method of claim 1 , wherein the first group common DCI comprises one or more group common physical downlink shared channel (PDSCH) parameters, for the first TB, indicating:

a number of one or more resource blocks (RBs) of a common frequency resource within a bandwidth part (BWP);

one or more symbols of one or more slots; and

a modulation and coding scheme.

6. The method of claim 1 , wherein the parameters comprise an MBS specific radio network temporary identifier (RNTI) associated with the MBS.

7. The method of claim 6 , further comprising transmitting the first group common DCI with cyclic redundancy check (CRC) bits, of the first group common DCI, scrambled by the MBS specific RNTI.

8. The method of claim 6 , further comprising transmitting the first TB with CRC bits, of the first TB, scrambled by the MBS specific RNTI.

9. The method of claim 1 , wherein the RRC messages further comprise second parameters of a second MBS, wherein the second parameters indicate a second MBS specific RNTI associated with the second MBS.

10. The method of claim 9 , wherein the second MBS specific RNTI is different from the MBS specific RNTI associated with the MBS.

11. The method of claim 10 , wherein the second parameters indicate HARQ feedback operations, for the second MBS, comprising:

the first feedback operation with HARQ feedback being enabled; and

the second feedback operation with HARQ feedback being disabled;

wherein a second group common DCI indicates one of the first or second HARQ feedback operation for the second MBS.

12. The method of claim 11 , further comprising:

transmitting, based on the second MBS specific RNTI, the second group common DCI:

scheduling a second TB of the second MBS; and

indicating the HARQ feedback being disabled,

wherein, based on the HARQ feedback being disabled, a transmission of the HARQ feedback for the second TB is skipped.

13. The method of claim 1 , wherein the parameters indicate a common frequency resource, within a BWP of a cell, associated with the MBS, wherein the common frequency resource is used for receptions of the first group common DCI and the first TB for a plurality of wireless devices comprising the wireless device.

14. The method of claim 1 , further comprising:

transmitting, based on the parameters, a second group common DCI indicating:

a downlink assignment for a second TB of the MBS; and

the second feedback operation; and

transmitting the second TB,

wherein, based on the second group common DCI indicating the second feedback operation, a transmission of a second HARQ feedback for the second TB is skipped.

15. The method of claim 1 , further comprising receiving, from the wireless device by a base station, a message comprising an MBS interest indication indicating that the wireless device is interested in the MBS.

16. A base station comprising:

one or more processors; and

memory storing instructions that, when executed by the one or more processors, cause the base station to:

transmit, to a wireless device, radio resource control (RRC) messages comprising parameters of a multicast and broadcast service (MBS),

wherein the parameters indicate:

a first feedback operation with hybrid automatic repeat request (HARQ) feedback being enabled; and

a second feedback operation with the HARQ feedback being disabled; and

wherein a group common downlink control information (DCI) indicates one of the first feedback operation or the second feedback operation;

transmit a first group common DCI:

scheduling a first transport block (TB) of the MBS; and

indicating the first feedback operation; and

receive, based on the first group common DCI indicating the first feedback operation, a first HARQ feedback for the first TB.

17. The base station of claim 16 , wherein the parameters comprise an MBS specific radio network temporary identifier (RNTI) associated with the MBS.

18. The base station of claim 17 , wherein the first group common DCI with cyclic redundancy check (CRC) bits, of the first group common DCI, is scrambled by the MBS specific RNTI.

19. The base station of claim 16 , wherein the RRC messages further comprise second parameters of a second MBS, wherein the second parameters indicate a second MBS specific RNTI associated with the second MBS.

20. The base station of claim 19 , wherein the second MBS specific RNTI is different from the MBS specific RNTI associated with the MBS.