Virtual search spaces for beam indication
Methods, systems, and devices for wireless communications are described. A base station may identify time and frequency resources for a physical downlink shared channel (PDSCH) to be transmitted to a user equipment (UE) in a first transmission time interval (TTI). The base station may transmit configuration information for a control channel search space set in a second TTI. The second TTI may precede the first TTI. The configuration information may include an indication of an absence of a physical downlink control channel (PDCCH) transmission to send in the control channel search space set indicating the identified time and frequency resources for the PDSCH, and a set of time and frequency resources for the control channel search space set. The UE may receive the configuration information and identify the time and frequency resources allocated for the PDSCH in the second TTI, and receive the PDSCH transmission in the second TTI.
1. An apparatus, comprising:
one or more memories storing processor-executable code; and
one or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the apparatus to:
receive a first control message comprising an indication of a plurality of resources allocated for a semi-persistently scheduled (SPS) physical downlink shared channel (PDSCH) and an indication of a first transmission configuration indication (TCI) state;
receive configuration information for a control channel search space set, the configuration information comprising an indication of an absence of a physical downlink control channel (PDCCH) transmission in the control channel search space set; and
receive a transmission associated with the SPS PDSCH in a resource of the plurality of resources using a beam associated with a second TCI state, the second TCI state being associated with a control resource set (CORESET) associated with the control channel search space set.
2. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the apparatus to:
determine that the CORESET is a closest CORESET to the resource, wherein the second TCI state is based at least in part on the CORESET being the closest CORESET to the resource.
3. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the apparatus to:
refrain from performing blind decoding in the control channel search space set based at least in part on receiving the indication of the absence of the PDCCH transmission.
4. The apparatus of claim 1 , wherein, to receive the configuration information for the control channel search space set, the one or more processors are individually or collectively operable to execute the code to cause the apparatus to:
receive the configuration information for the control channel search space set via radio resource control (RRC) signaling.
5. The apparatus of claim 1 , wherein the configuration information comprises a configuration associated with the CORESET, a set of transmission configuration indication (TCI) states comprising at least the first TCI state and the second TCI state, or both.
6. The apparatus of claim 1 , wherein the first TCI state and the second TCI state comprise one or more spatial quasi-collocation (QCL) parameters.
7. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the apparatus to:
apply the second TCI state based at least in part on the CORESET associated with the control channel search space set being associated with a latest slot of a set of slots comprising the CORESET and one or more other CORESETs.
8. The apparatus of claim 1 , wherein the CORESET comprises a virtual search space set comprising a beam indication for receiving the transmission associated with the SPS PDSCH.
9. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the apparatus to:
receive a second transmission associated with the SPS PDSCH using the beam associated with the first TCI state based at least in part on an offset of the second transmission associated with the SPS PDSCH relative to the first control message being less than or equal to a threshold value.
10. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the apparatus to:
receive the transmission associated with the SPS PDSCH using the beam associated with the second TCI state based at least in part on an offset of the transmission associated with the SPS PDSCH relative to the first control message being greater than or equal to a threshold value.
11. The apparatus of claim 1 , wherein the control channel search space set associated with the CORESET comprises a zero number of PDCCH candidates.
12. A method for wireless communications at a user equipment (UE) comprising:
receiving a first control message comprising an indication of a plurality of resources allocated for a semi-persistently scheduled (SPS) physical downlink shared channel (PDSCH) and an indication of a first transmission configuration indication (TCI) state;
receiving configuration information for a control channel search space set, the configuration information comprising an indication of an absence of a physical downlink control channel (PDCCH) transmission in the control channel search space set; and
receiving a transmission associated with the SPS PDSCH in a resource of the plurality of resources using a beam associated with a second TCI state, the second TCI state being associated with a control resource set (CORESET) associated with the control channel search space set.
13. The method of claim 12 , further comprising:
determining that the CORESET is a closest CORESET to the resource, wherein the second TCI state is based at least in part on the CORESET being the closest CORESET to the resource.
14. The method of claim 12 , further comprising:
refraining from performing blind decoding in the control channel search space set based at least in part on receiving the indication of the absence of the PDCCH transmission.
15. The method of claim 12 , wherein receiving the configuration information for the control channel search space set comprises:
receive the configuration information for the control channel search space set via radio resource control (RRC) signaling.
16. The method of claim 12 , wherein the configuration information comprises a configuration associated with the CORESET, a set of transmission configuration indication (TCI) states comprising at least the first TCI state and the second TCI state, or both.
17. The method of claim 12 , wherein the first TCI state and the second TCI state comprise one or more spatial quasi-collocation (QCL) parameters.
18. The method of claim 12 , further comprising:
applying the second TCI state based at least in part on the CORESET associated with the control channel search space set being associated with a latest slot of a set of slots comprising the CORESET and one or more other CORESETs.
19. The method of claim 12 , wherein the CORESET comprises a virtual search space set comprising a beam indication for receiving the transmission associated with the SPS PDSCH.
20. An apparatus for wireless communications, comprising:
means for receiving a first control message comprising an indication of a plurality of resources allocated for a semi-persistently scheduled (SPS) physical downlink shared channel (PDSCH) and an indication of a first transmission configuration indication (TCI) state;
means for receiving configuration information for a control channel search space set, the configuration information comprising an indication of an absence of a physical downlink control channel (PDCCH) transmission in the control channel search space set; and
means for receiving a transmission associated with the SPS PDSCH in a resource of the plurality of resources using a beam associated with a second TCI state, the second TCI state being associated with a control resource set (CORESET) associated with the control channel search space set.