Physical downlink control channel transmissions for multicast/broadcast system services
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may monitor a search space associated with a physical downlink control channel (PDCCH) corresponding to a multicast/broadcast (MBS) physical downlink shared channel (PDSCH) for at least one MBS PDCCH communication having a payload that is scrambled according to a PDCCH payload scrambling sequence based on a value of a radio network temporary identifier (RNTI), wherein the value of the RNTI is equal to a group-RNTI (G-RNTI) or zero. The UE may receive the at least one MBS PDCCH communication. Numerous other aspects are described.
1. A user equipment (UE) for wireless communication, comprising:
a memory; and
one or more processors, coupled to the memory, configured to:
monitor a search space associated with a physical downlink control channel (PDCCH) corresponding to a multicast/broadcast system (MBS) physical downlink shared channel (PDSCH) for at least one MBS PDCCH communication having a control channel element (CCE) index corresponding to a hash function that is based on a value of a radio network temporary identifier (RNTI), wherein the value of the RNTI is equal to a group-RNTI (G-RNTI); and
receive the at least one MBS PDCCH communication.
2. The UE of claim 1 , wherein the one or more processors are further configured to receive an indication of a radio resource control (RRC) parameter that enables the RNTI to equal the G-RNTI, wherein the value of the RNTI is equal to the G-RNTI based on receiving the indication of the RRC parameter.
3. The UE of claim 1 , wherein the one or more processors are further configured to receive a dedicated configuration indication that configures the search space, wherein the value of the RNTI is equal to the G-RNTI based on receiving the dedicated configuration indication.
4. The UE of claim 1 , wherein the one or more processors, to monitor the search space, are configured to monitor the search space only in a radio resource control (RRC) connected state, and wherein the value of the RNTI is equal to the G-RNTI based on monitoring the search space only in the RRC connected state.
5. The UE of claim 1 , wherein the at least one MBS PDCCH communication comprises a downlink control information (DCI) transmission that schedules an MBS physical downlink shared channel.
6. The UE of claim 1 , wherein the at least one MBS PDCCH communication schedules a plurality of MBS physical downlink shared channel (PDSCH) communications, wherein each MBS PDSCH communication of the plurality of MBS PDSCH communications is associated with a respective G-RNTI of a plurality of G-RNTIs that includes the G-RNTI.
7. The UE of claim 6 , wherein the value of the RNTI is equal to the G-RNTI and wherein at least one additional CCE index corresponds to at least one additional hash function that is based on at least one additional value of the RNTI, wherein the at least one additional value of the RNTI is equal to at least one additional G-RNTI of the plurality of G-RNTIs.
8. The UE of claim 6 , wherein at least one additional hash function is based on at least one additional value of the RNTI, wherein the at least one additional value of the RNTI is equal to the value of the RNTI.
9. The UE of claim 8 , wherein the value of the RNTI is equal to a G-RNTI mapped to a multicast service.
10. The UE of claim 6 , wherein the at least one MBS PDCCH communication comprises a plurality of MBS PDCCH communications.
11. The UE of claim 6 , wherein the one or more processors are further configured to monitor at least one additional search space for at least one additional MBS PDCCH that schedules at least one additional MBS PDSCH communication associated with at least one additional G-RNTI of the plurality of G-RNTIs.
12. The UE of claim 1 , wherein the one or more processors are further configured to receive a radio resource control configuration that indicates a mapping between the search space and the G-RNTI.
13. A network node for wireless communication, comprising:
a memory; and
one or more processors, coupled to the memory, configured to:
transmit a multicast/broadcast system (MBS) configuration that indicates a physical downlink control channel (PDCCH) hash function based on a value of a radio network temporary identifier (RNTI) for a search space associated with a PDCCH corresponding to an MBS physical downlink shared channel (PDSCH), wherein the value of the RNTI is equal to a group-RNTI (G-RNTI); and
transmit at least one MBS PDCCH communication based at least in part on the configuration.
14. The network node of claim 13 , wherein the one or more processors are further configured to transmit an indication of a radio resource control (RRC) parameter that enables the RNTI to equal the G-RNTI, wherein the value of the RNTI is equal to the G-RNTI based on transmitting the indication of the RRC parameter.
15. The network node of claim 13 , wherein the one or more processors are further configured to transmit a dedicated configuration indication that configures the search space, wherein the value of the RNTI is equal to the G-RNTI based on transmitting the dedicated configuration indication.
16. The network node of claim 13 , wherein the one or more processors are further configured to transmit a monitoring configuration that indicates that a user equipment (UE) is to monitor the search space only in a radio resource control (RRC) connected state, and wherein the value of the RNTI is equal to the G-RNTI based on the monitoring configuration.
17. The network node of claim 13 , wherein the at least one MBS PDCCH communication schedules a plurality of MBS physical downlink shared channel (PDSCH) communications, wherein each MBS PDSCH communication of the plurality of MBS PDSCH communications is associated with a respective G-RNTI of a plurality of G-RNTIs that includes the G-RNTI.
18. The network node of claim 17 , wherein the value of the RNTI is equal to the G-RNTI and wherein at least one additional CCE index corresponds to at least one additional hash function that is based on at least one additional value of the RNTI, wherein the at least one additional value of the RNTI is equal to at least one additional G-RNTI of the plurality of G-RNTIs.
19. The network node of claim 18 , wherein at least one additional hash function is based on at least one additional value of the RNTI, wherein the at least one additional value of the RNTI is equal to the value of the RNTI.
20. The network node of claim 19 , wherein the value of the RNTI is equal to a specified G-RNTI of the plurality of G-RNTIs.
21. The network node of claim 19 , wherein the plurality of G-RNTIs are configured using a G-RNTI list, and wherein the value of the RNTI is equal to a first listed G-RNTI of the G-RNTI list.
22. The network node of claim 19 , wherein the value of the RNTI is equal to a G-RNTI mapped to a multicast service.
23. The network node of claim 22 , wherein the multicast service comprises a specified multicast service identifier (ID) of a plurality of multicast service IDs.
24. The network node of claim 17 , wherein the at least one MBS PDCCH communication comprises a plurality of MBS PDCCH communications.
25. A method of wireless communication performed by a user equipment (UE), comprising:
monitoring a search space associated with a physical downlink control channel (PDCCH) corresponding to a multicast/broadcast system (MBS) physical downlink shared channel (PDSCH) for at least one MBS PDCCH communication having a control channel element (CCE) index corresponding to a hash function that is based on a value of a radio network temporary identifier (RNTI), wherein the value of the RNTI is equal to a group-RNTI (G-RNTI); and
receiving the at least one MBS PDCCH communication.
26. The method of claim 25 , the method further comprising receiving an indication of a radio resource control (RRC) parameter that enables the RNTI to equal the G-RNTI, wherein the value of the RNTI is equal to the G-RNTI based on receiving the indication of the RRC parameter.
27. The method of claim 25 , wherein monitoring the search space comprises monitoring the search space only in a radio resource control (RRC) connected state, wherein the value of the RNTI is equal to the G-RNTI based on monitoring the search space only in the RRC connected state.
28. A method of wireless communication performed by a network node, comprising:
transmitting a multicast/broadcast system (MBS) configuration that indicates a physical downlink control channel (PDCCH) payload scrambling sequence based on a value of a radio network temporary identifier (RNTI) for a search space associated with a PDCCH corresponding to an MBS physical downlink shared channel (PDSCH), wherein the value of the RNTI is equal to a group-RNTI (G-RNTI); and
transmitting at least one MBS PDCCH communication based at least in part on the configuration.
29. The method of claim 28 , the method further comprising transmitting an indication of a radio resource control (RRC) parameter that enables the RNTI to equal the G-RNTI, wherein the value of the RNTI is equal to the G-RNTI based on transmitting the indication of the RRC parameter.
30. The method of claim 28 , the method further comprising transmitting a dedicated configuration indication that configures the search space, wherein the value of the RNTI is equal to the G-RNTI based on transmitting the dedicated configuration indication.