Power headroom report procedure for a wireless network
Aspects of the disclosure relate to communication of power headroom reports in wireless communication networks. A user equipment (UE) may measure a path loss based on a triggering path loss reference signal (PL-RS) and trigger generation of a power headroom report (PHR) based on the path loss. The UE may identify uplink resources for communication of the PHR to a base station and determine whether the uplink resources are quasi-co-located with the triggering PL-RS. When the uplink resources are quasi-co-located with the triggering PL-RS, the user equipment may transmit the PHR utilizing the uplink resources. Otherwise, the UE may generate the PHR such that it includes information identifying the triggering PL-RS.
1. A method of wireless communication at a scheduled entity, comprising:
measuring a path loss based on a triggering path loss reference signal (PL-RS) of a plurality of PL-RS;
triggering generation of a power headroom report (PHR) based on the path loss;
identifying uplink resources for communication of the PHR to a scheduling entity;
determining whether the uplink resources are quasi-co-located (QCLd) with the triggering PL-RS; and
transmitting the PHR over the uplink resources, wherein the PHR indicates the triggering PL-RS, wherein the PHR comprises information associated with the triggering PL-RS when the uplink resources are not QCLd with the triggering PL-RS, and wherein the PHR excludes the information associated with the triggering PL-RS when the uplink resources are QCLd with the triggering PL-RS.
2. The method of claim 1 , wherein the information associated with the triggering PL-RS comprises a first index of the triggering PL-RS.
3. The method of claim 2 , wherein the information associated with the triggering PL-RS further comprises at least one of a second index of a serving cell corresponding to the triggering PL-RS or a power headroom value corresponding to the triggering PL-RS.
4. The method of claim 2 , further comprising:
generating a medium access control (MAC) control element (CE) comprising the first index of the triggering PL-RS.
5. The method of claim 1 , further comprising:
receiving one or more parameters indicating whether the uplink resources are quasi-co-located (QCLd) with the triggering PL-RS.
6. The method of claim 5 , wherein the one or more parameters comprises a transmission configuration indicator (TCI) state.
7. The method of claim 1 , wherein triggering generation of the PHR further comprises:
triggering generation of the PHR when a change in the path loss is greater than a threshold value.
8. The method of claim 1 , further comprising:
receiving at least one previous uplink grant of additional uplink resources; and
preventing the scheduled entity from utilizing the additional uplink resources to transmit the PHR when the additional uplink resources are not QCLd with the triggering PL-RS.
9. A scheduled entity configured for wireless communication, comprising:
a processor;
a transceiver communicatively coupled to the processor; and
a memory communicatively coupled to the processor, wherein the processor is configured to:
measure a path loss based on a triggering path loss reference signal (PL-RS) of a plurality of PL-RS;
trigger generation of a power headroom report (PHR) based on the path loss;
identify uplink resources for communication of the PHR to a scheduling entity;
determine whether the uplink resources are quasi-co-located (QCLd) with the triggering PL-RS; and
transmit the PHR over the uplink resources via the transceiver, wherein the PHR indicates the triggering PL-RS, wherein the PHR comprises information associated with the triggering PL-RS when the uplink resources are not QCLd with the triggering PL-RS, and wherein the PHR excludes the information associated with the triggering PL-RS when the uplink resources are QCLd with the triggering PL-RS.
10. The scheduled entity of claim 9 , wherein the information associated with the triggering PL-RS comprises a first index of the triggering PL-RS.
11. The scheduled entity of claim 10 , wherein the information associated with the triggering PL-RS further comprises at least one of a second index of a serving cell corresponding to the triggering PL-RS or a power headroom value corresponding to the triggering PL-RS.
12. The scheduled entity of claim 10 , wherein the processor is further configured to:
generate a medium access control (MAC) control element (CE) comprising the first index of the triggering PL-RS.
13. The scheduled entity of claim 9 , wherein the processor is further configured to:
receive one or more parameters indicating whether the uplink resources are quasi-co-located (QCLd) with the triggering PL-RS.
14. The scheduled entity of claim 13 , wherein the one or more parameters comprises a transmission configuration indicator (TCI) state.
15. The scheduled entity of claim 9 , wherein the processor is further configured to:
trigger generation of the PHR when a change in the path loss is greater than a threshold value.
16. The scheduled entity of claim 9 , wherein the processor is further configured to:
receive at least one previous uplink grant of additional uplink resources; and
prevent the scheduled entity from utilizing the additional uplink resources to transmit the PHR when the additional uplink resources are not QCLd with the triggering PL-RS.
17. A method of wireless communication at a scheduling entity, comprising:
transmitting a plurality of path loss reference signals (PL-RS) comprising a triggering PL-RS to a user equipment (UE);
scheduling uplink resources for use by the scheduling entity; and
receiving a power headroom report (PHR) over the uplink resources in response to the triggering PL-RS, wherein the PHR indicates the triggering PL-RS, wherein the PHR comprises information associated with the triggering PL-RS when the uplink resources are not quasi-co-located (QCLd) with the triggering PL-RS, and wherein the PHR excludes the information associated with the triggering PL-RS when the uplink resources are QCLd with the triggering PL-RS.
18. The method of claim 17 , wherein the information associated with the triggering PL-RS comprises a first index of the triggering PL-RS.
19. The method of claim 18 , wherein the information associated with the triggering PL-RS further comprises at least one of a second index configured to identify a serving cell corresponding to the triggering PL-RS or a power headroom value corresponding to the triggering PL-RS.
20. The method of claim 18 , wherein the PHC comprises a medium access control (MAC) control element (CE) comprising the first index of the triggering PL-RS.
21. The method of claim 17 , further comprising:
transmitting one or more parameters indicating whether the uplink resources are quasi-co-located (QCLd) with the triggering PL-RS.
22. The method of claim 21 , wherein the one or more parameters comprises a transmission configuration indicator (TCI) state.
23. A scheduling entity configured for wireless communication, comprising:
a processor;
a transceiver communicatively coupled to the processor; and
a memory communicatively coupled to the processor, wherein the processor is configured to:
transmit a plurality of path loss reference signals (PL-RS) comprising a triggering PL-RS to a user equipment (UE) via the transceiver;
schedule uplink resources for use by the scheduling entity; and
receive a power headroom report (PHR) within the uplink resources in response to the triggering PL-RS, wherein the PHR indicates the triggering PL-RS, wherein the PHR comprises information associated with the triggering PL-RS when the uplink resources are not quasi-co-located (QCLd) with the triggering PL-RS, and wherein the PHR excludes the information associated with the triggering PL-RS when the uplink resources are QCLd with the triggering PL-RS.
24. The scheduling entity of claim 23 , wherein the information associated with the triggering PL-RS comprises a first index of the triggering PL-RS and further comprises at least one of a second index configured to identify a serving cell corresponding to the triggering PL-RS or a power headroom value corresponding to the triggering PL-RS.