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 determining that an uplink resource for a new transmission on a serving cell of the multiple serving cells is allocated at a first time after the power headroom report is triggered. 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 a predetermined time before the start of the uplink resource at 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 a plurality of serving cells;
determining that a power headroom report is triggered;
determining that an uplink resource for a new transmission on a serving cell of the plurality of serving cells is allocated at a first time after the power headroom report is triggered, wherein the uplink resource for the new transmission allocated at the first time is a configured grant;
determining a power headroom value for each serving cell of the plurality of serving cells being activated based on information received prior to and including a predetermined time before the start of the uplink resource at the first time, wherein the information comprises downlink control information, higher layer signaling for configured grants, an uplink resource allocation for the configured grants, and signaling for sounding reference signal transmissions;
generating a power headroom report medium access control control element comprising at least the power headroom value for each serving cell of the plurality of serving cells being activated; and
transmitting the power headroom report medium access control control element on the uplink resource allocated at the first time.
2. The method of claim 1 , wherein the predetermined time is a fixed number of slots, a fixed number of orthogonal frequency-division multiplexing symbols, or some combination thereof before the start of the uplink resource at the first time.
3. The method of claim 1 , wherein the predetermined time is a physical downlink control channel occasion in which an uplink grant is received, and the uplink grant allocates uplink resources for the new transmission at the first time after the power headroom report is triggered.
4. The method of claim 1 , wherein the information comprises uplink related downlink control information.
5. The method of claim 1 , wherein the information comprises physical layer grants, higher layer signaling, or some combination thereof.
6. The method of claim 5 , wherein the physical layer grants comprise uplink related downlink control information formats.
7. The method of claim 5 , wherein the higher layer signaling comprises uplink resource related radio resource control signaling, medium access control control element signaling, or some combination thereof.
8. The method of claim 1 , wherein the information comprises uplink related downlink control information that has corresponding uplink transmissions that occur at the first time, occur after the first time, occur before a first symbol of the new transmission that carries the power headroom report, occur at the first symbol of the new transmission that carries the power headroom report, overlap the new transmission that carries the power headroom report, or some combination thereof.
9. The method of claim 1 , wherein the information comprises transmit power control commands signaled by downlink control information.
10. The method of claim 1 , wherein the first uplink allocation comprises an allocation by higher layer signaling without receiving a first uplink grant.
11. The method of claim 1 , wherein the first time is at a time in which the power headroom report is triggered.
12. The method of claim 1 , wherein the first time corresponds to a physical downlink control channel occasion.
13. The method of claim 1 , wherein determining the power headroom value for each serving cell of the plurality of serving cells comprises determining whether the power headroom value for each serving cell of the plurality of serving cells being activated is based on a real uplink transmission or a reference format.
14. The method of claim 1 , wherein the power headroom report medium access control control element comprises an indicator corresponding to each serving cell of the plurality of serving cells being activated, and the indicator indicates whether the power headroom value for a corresponding serving cell is real or virtual.
15. The method of claim 1 , wherein the power headroom report comprises a power headroom corresponding to each serving cell of the plurality of serving cells being activated, and the power headroom for a corresponding serving cell is real or virtual.
16. The method of claim 1 , wherein the power headroom report is triggered in response to a timer expiring.
17. The method of claim 1 , wherein the predetermined time is a user equipment processing time value for preparation of a physical uplink shared channel transmission.
18. The method of claim 1 , wherein determining the power headroom value for each serving cell of the plurality of serving cells being activated comprises determining whether the power headroom value for each serving cell of the plurality of serving cells being activated is based on a real uplink transmission or a reference format.
19. The method of claim 1 , wherein the information comprises signaling for periodic and semi-persistent sounding reference signal transmissions.
20. An apparatus comprising:
a processor that:
aggregates a plurality of serving cells;
determines that a power headroom report is triggered;
determines that an uplink resource for a new transmission on a serving cell of the plurality of serving cells is allocated at a first time after the power headroom report is triggered, wherein the uplink resource for the new transmission allocated at the first time is a configured grant;
determines a power headroom value for each serving cell of the plurality of serving cells being activated based on information received prior to and including a predetermined time before the start of the uplink resource at the first time, wherein the information comprises downlink control information, higher layer signaling for configured grants, an uplink resource allocation for the configured grants, and signaling for sounding reference signal transmissions;
generates a power headroom report medium access control control element comprising at least the power headroom value for each serving cell of the plurality of serving cells being activated; and
transmits the power headroom report medium access control control element on the uplink resource allocated at the first time.
21. The apparatus of claim 20 , wherein the processor determining the power headroom value for each serving cell of the plurality of serving cells comprises the processor determining whether the power headroom value for each serving cell of the plurality of serving cells being activated is based on a real uplink transmission or a virtual uplink transmission.