Method and apparatus for power headroom reporting procedure for different serving cells

1. A method in a user equipment, the method comprising:

being configured with

a first serving cell for physical uplink shared channel transmissions having a first subcarrier spacing and a first slot length and

a second serving cell for physical uplink shared channel transmissions having a second subcarrier spacing and a second slot length,

the first subcarrier spacing being smaller than the second subcarrier spacing and the first slot length being larger than the second slot length;

determining that a power headroom report has been triggered;

having an uplink allocation corresponding to an uplink transmission in an allocated slot on the first serving cell,

the allocated slot on the first serving cell overlapping with multiple slots on the second serving cell,

generating a first power headroom report for the allocated slot on the first serving cell;

generating a second power headroom report for the second serving cell,

wherein the second power headroom report is generated for a first slot of the multiple overlapping slots on the second serving cell that fully overlaps with the allocated slot on the first serving cell; and

transmitting the first power headroom report and the second power headroom report in the uplink transmission in the allocated slot on the first serving cell,

wherein the first power headroom report and the second power headroom report are Type 1 power headroom reports.

2. The method according to claim 1 ,

wherein being configured comprises configuring the user equipment with

a first serving cell for physical uplink shared channel transmissions having a first subcarrier spacing and a first slot length and

a second serving cell for physical uplink shared channel transmissions having a second subcarrier spacing and a second slot length,

the first subcarrier spacing being smaller than the second subcarrier spacing and the first slot length being larger than the second slot length, and

wherein the method further comprises receiving the uplink allocation corresponding to the uplink transmission in the allocated slot on the first serving cell, the allocated slot on the first serving cell overlapping with multiple slots on the second serving cell.

3. The method according to claim 1 ,

wherein the multiple overlapping slots on the second serving cell comprise at least one slot that fully overlaps with the allocated slot on the first serving cell, and

wherein the at least one slot that fully overlaps with the allocated slot starts with the first slot of the at least one slot that fully overlaps with the allocated slot.

4. The method according to claim 1 , further comprising

receiving a first uplink grant including the uplink allocation, where the uplink transmission comprises a first uplink transmission;

determining a determined slot where a second uplink grant can be received, the second uplink grant corresponding to a second uplink transmission in the first slot of the multiple overlapping slots; and

monitoring for the second uplink grant in the determined slot,

wherein generating the second power headroom report comprises generating the second power headroom report for the second serving cell based on monitoring for the second uplink grant.

5. The method according to claim 4 , wherein the determined grant slot where the second uplink grant can be received is determined in response to determining that a power headroom report has been triggered and in response to receiving the first uplink grant.

6. The method according to claim 4 , wherein generating the second power headroom report comprises generating the second power headroom report for the first slot of the multiple overlapping slots when the second uplink grant is received in the determined slot.

7. The method according to claim 1 ,

wherein the allocated slot on the first serving cell begins at a first time, and

wherein the first slot of the multiple overlapping slots begins a second time, where the first time is before the second time.

8. The method according to claim 1 , wherein generating the second power headroom report comprises generating the second power headroom report based on a predefined numerology when using a predefined uplink transmission for the calculation of the second power headroom report.

9. The method according to claim 1 , wherein transmitting comprises transmitting the first power headroom report and the second power headroom report in a power headroom report medium access control control element in the uplink transmission in the allocated slot on the first serving cell.

10. The method according to claim 1 ,

wherein the first power headroom report indicates a difference between a user equipment configured maximum uplink transmit power of the first serving cell and an estimated power for an uplink shared channel transmission on the first serving cell, and

wherein the second power headroom report indicates a difference between a user equipment configured maximum uplink transmit power of the second serving cell and an estimated power for an uplink shared channel transmission on the second serving cell.

11. An apparatus comprising:

a memory including a configuration for a first serving cell for physical uplink shared channel transmissions having a first subcarrier spacing and a first slot length and a configuration for second serving cell for physical uplink shared channel transmissions having a second subcarrier spacing and a second slot length, the first subcarrier spacing being smaller than the second subcarrier spacing and the first slot length being larger than the second slot length; and

a controller that determines that a power headroom report has been triggered,

wherein the memory includes an uplink allocation corresponding to an uplink transmission in an allocated slot on the first serving cell, the allocated slot on the first serving cell overlapping with multiple slots on the second serving cell,

wherein the controller

generates a first power headroom report for the allocated slot on the first serving cell, and

generates a second power headroom report for the second serving cell, where the second power headroom report is generated for a first slot of the multiple overlapping slots on the second serving cell that fully overlaps with the allocated slot on the first serving cell,

wherein the apparatus further comprises a transceiver that transmits the first power headroom report and the second power headroom report in the uplink transmission in the allocated slot on the first serving cell, and

wherein the first power headroom report and the second power headroom report are Type 1 power headroom reports.

12. The apparatus according to claim 11 ,

wherein the transceiver receives a configuration that configures the apparatus with

a first serving cell for physical uplink shared channel transmissions having a first subcarrier spacing and a first slot length and

a second serving cell for physical uplink shared channel transmissions having a second subcarrier spacing and a second slot length,

the first subcarrier spacing being smaller than the second subcarrier spacing and the first slot length being larger than the second slot length, and

wherein the transceiver receives the uplink allocation corresponding to the uplink transmission in the allocated slot on the first serving cell, the allocated slot on the first serving cell overlapping with multiple slots on the second serving cell.

13. The apparatus according to claim 11 ,

wherein the multiple overlapping slots on the second serving cell comprise at least one slot that fully overlaps with the allocated slot on the first serving cell, and

wherein the at least one slot that fully overlaps with the allocated slot starts with the first slot of the at least one slot that fully overlaps with the allocated slot.

14. The apparatus according to claim 11 ,

wherein the transceiver receives a first uplink grant including the uplink allocation, where the uplink transmission comprises a first uplink transmission, and

wherein the controller

determines a determined slot where a second uplink grant can be received, the second uplink grant corresponding to a second uplink transmission in the first slot of the multiple overlapping slots, and

monitors for the second uplink grant in the determined slot, and

generates the second power headroom report for the second serving cell based on monitoring for the second uplink grant.

15. The apparatus according to claim 14 , wherein the determined grant slot where the second uplink grant can be received is determined in response to determining that a power headroom report has been triggered and in response to receiving the first uplink grant.

16. The apparatus according to claim 14 , wherein the controller generates the second power headroom report for the first slot of the multiple overlapping slots when the second uplink grant is received in the determined slot.

17. The apparatus according to claim 11 ,

wherein the allocated slot on the first serving cell begins at a first time, and

wherein the first slot of the multiple overlapping slots begins a second time, where the first time is before the second time.

18. The apparatus according to claim 11 , wherein the controller generates the second power headroom report based on a predefined numerology when using a predefined uplink transmission for the calculation of the second power headroom report.

19. The apparatus according to claim 11 , wherein the transceiver transmits the first power headroom report and the second power headroom report in a power headroom report medium access control control element in the uplink transmission in the allocated slot on the first serving cell.

20. The apparatus according to claim 11 ,

wherein the first power headroom report indicates a difference between a user equipment configured maximum uplink transmit power of the first serving cell and an estimated power for an uplink shared channel transmission on the first serving cell, and

wherein the second power headroom report indicates a difference between a user equipment configured maximum uplink transmit power of the second serving cell and an estimated power for an uplink shared channel transmission on the second serving cell.

21. The method according to claim 1 , wherein transmitting comprises transmitting the first power headroom report and the second power headroom report in a power headroom report medium access control control element in the uplink transmission in the allocated slot on the first serving cell.

22. The apparatus according to claim 11 , wherein the transceiver transmits the first power headroom report and the second power headroom report in a power headroom report medium access control control element in the uplink transmission in the allocated slot on the first serving cell.