Power headroom report generation
Apparatuses, methods, and systems are disclosed for power headroom report generation. One method includes aggregating multiple serving cells. The method includes determining that a power headroom report is triggered. The method includes receiving, at a first time after the power headroom report is triggered, a first uplink grant that allocates resources for a new transmission on a serving cell of the multiple serving cells. The method includes determining a power headroom value for each serving cell of the multiple serving cells being activated based on information received prior to and including the first time. The method includes generating a power headroom report medium access control control element including at least the power headroom value for each serving cell of the multiple serving cells being activated.
1. A method comprising:
aggregating multiple serving cells;
determining that a power headroom report is triggered;
receiving, at a time after the power headroom report is triggered, an uplink grant that allocates uplink resources for an initial transmission;
determining whether a power headroom report is real or virtual;
in response to determining that the power headroom report is virtual, computing a power headroom value for an activated serving cell of the multiple serving cells based on a reference physical uplink shared channel transmission, wherein the power headroom value is computed using a predefined set of power control parameters;
generating a power headroom report medium access control control element comprising the power headroom value; and
transmitting the power headroom report medium access control control element on the uplink resources allocated by the uplink grant.
2. The method of claim 1 , wherein the time corresponds to a physical downlink control channel occasion.
3. The method of claim 1 , wherein the power headroom report is a type 1 power headroom report.
4. The method of claim 1 , wherein the power headroom report medium access control control element comprises an indicator that indicates that the power headroom value is virtual.
5. The method of claim 1 , wherein the power headroom report is triggered in response to a timer expiring.
6. The method of claim 1 , wherein the predefined set of power control parameters comprises open loop power control parameters.
7. The method of claim 1 , wherein the predefined set of power control parameters comprises an alpha value.
8. The method of claim 1 , wherein the predefined set of power control parameters comprises a power level.
9. The method of claim 1 , wherein the predefined set of power control parameters comprises P 0 .
10. The method of claim 1 , wherein the predefined set of power control parameters is a power control parameter set out of a plurality of configured power control parameter sets, and each power control parameter set of the plurality of configured power control parameter sets comprises a power level and an alpha value.
11. The method of claim 10 , wherein the power headroom value is computed using the power level and the alpha value of the power control parameter set which is a first listed power control parameter set in the plurality of configured power control parameter sets.
12. An apparatus comprising:
a processor that:
aggregates multiple serving cells; and
determines that a power headroom report is triggered;
a receiver that receives, at a time after the power headroom report is triggered, an uplink grant that allocates uplink resources for an initial transmission, wherein:
the processor:
determines whether a power headroom report is real or virtual;
in response to determining that the power headroom report is virtual, computes a power headroom value for an activated serving cell of the multiple serving cells based on a reference physical uplink shared channel transmission, wherein the power headroom value is computed using a predefined set of power control parameters; and
generates a power headroom report medium access control control element comprising the power headroom value; and
a transmitter that transmits the power headroom report medium access control control element on the uplink resources allocated by the uplink grant.
13. The apparatus of claim 12 , wherein the time corresponds to a physical downlink control channel occasion.
14. The apparatus of claim 12 , wherein the power headroom report is a type 1 power headroom report.
15. The apparatus of claim 12 , wherein the power headroom report medium access control control element comprises an indicator that indicates that the power headroom value is virtual.
16. The apparatus of claim 12 , wherein the power headroom report is triggered in response to a timer expiring.
17. The apparatus of claim 12 , wherein the predefined set of power control parameters comprises open loop power control parameters.
18. The apparatus of claim 12 , wherein the predefined set of power control parameters comprises an alpha value.
19. The apparatus of claim 12 , wherein the predefined set of power control parameters comprises a power level.
20. The apparatus of claim 12 , wherein the predefined set of power control parameters comprises P 0 .
21. The apparatus of claim 12 , wherein the predefined set of power control parameters is a power control parameter set out of a plurality of configured power control parameter sets, and each power control parameter set of the plurality of configured power control parameter sets comprises a power level and an alpha value.
22. The apparatus of claim 21 , wherein the power headroom value is computed using the power level and the alpha value of the power control parameter set which is a first listed power control parameter set in the plurality of configured power control parameter sets.
23. A method comprising:
determining that a power headroom report is triggered;
receiving, at a time after the power headroom report is triggered, a first uplink grant that allocates first uplink resources for transmitting a power headroom report medium access control control element;
receiving a second uplink grant that allocates second uplink resources for an uplink transmission, wherein the second uplink resources are in a same transmission time interval as the first uplink resources; and
ignoring the second uplink grant.
24. An apparatus comprising:
a processor that determines that a power headroom report is triggered; and
a receiver that:
receives, at a time after the power headroom report is triggered, a first uplink grant that allocates first uplink resources for transmitting a power headroom report medium access control control element; and
receives a second uplink grant that allocates second uplink resources for an uplink transmission, wherein the second uplink resources are in a same transmission time interval as the first uplink resources, wherein the processor ignores the second uplink grant.