Reporting power headroom in multiple connectivity next generation networks

1. A method for reporting power headroom by a user equipment (UE) to an evolved NodeB (eNB) in a Multi-Radio Access Technology (RAT)-Dual Connectivity (MR-DC) scenario, the method comprising:

generating, by the UE, a DC Power Headroom Report (PHR) Medium Access Control (MAC) Control Element (CE) having a fixed number of octets with cell index fields for indicating whether a power headroom (PH) for a serving cell with a corresponding cell index is reported; and

transmitting, by the UE, the DC PHR MAC CE to the eNB,

wherein the fixed number of octets is independent of a highest secondary Cell Index (SCellIndex) for serving cells with configured uplink.

2. The method of claim 1 , wherein the fixed number of octets is four for the DC PHR MAC CE.

3. The method of claim 1 , wherein a logical channel identifier (LCID) identifies the DC PHR MAC CE for both single-octet bitmap with cell index fields and four-octet bitmap with cell index fields.

4. The method of claim 1 , wherein the DC PHR MAC CE is identified by a MAC PDU subheader including at least one of:

an LCID for reporting the DC PHR MAC CE using a single-octet bitmap; and

an LCID for reporting the DC PHR MAC CE using a four-octet bitmap.

5. The method of claim 1 , wherein the DC PHR MAC CE is identified by a MAC PDU subheader with an LCID for reporting the DC PHR MAC CE using a four-octet bitmap when the eNB is a secondary node.

6. The method of claim 1 , wherein, when the eNB is a secondary node, the DC PHR MAC CE is identified by a MAC PDU subheader including at least one of:

an LCID for reporting the DC PHR MAC CE using a one-octet bitmap; and

an LCID for reporting the DC PHR MAC CE using a four-octet bitmap.

7. A user equipment (UE) configured to report power headroom to an evolved NodeB (eNB) in a Multi-Radio Access Technology (RAT)—Dual Connectivity (MR-DC) scenario, the UE comprising:

one or more non-transitory computer-readable media having computer-executable instructions embodied thereon; and

at least one processor coupled to the one or more non-transitory computer-readable media, and configured to execute the computer-executable instructions to:

generate a DC Power Headroom Report (PHR) Medium Access Control (MAC) Control Element (CE) having a fixed number of octets with cell index fields for indicating whether a power headroom (PH) for a serving cell with a corresponding cell index is reported; and

transmit the DC PHR MAC CE to the eNB,

wherein the fixed number of octets is independent of a highest secondary Cell Index (SCellIndex) for serving cells with configured uplink.

8. The UE of claim 7 , wherein the fixed number of octets is four for the DC PHR MAC CE.

9. The method of claim 7 , wherein a logical channel identifier (LCID) identifies the DC PHR MAC CE for both single-octet bitmap with cell index fields and four-octet bitmap with cell index fields.

10. The method of claim 7 , wherein the DC PHR MAC CE is identified by a MAC PDU subheader including at least one of:

an LCID for reporting the DC PHR MAC CE using a single-octet bitmap; and

an LCID for reporting the DC PHR MAC CE using a four-octet bitmap.

11. The UE of claim 7 , wherein the DC PHR MAC CE is identified by a MAC PDU subheader with an LCID for reporting the DC PHR MAC CE using a four-octet bitmap when the eNB is a secondary node.

12. The method of claim 7 , wherein, when the eNB is a secondary node, the DC PHR MAC CE is identified by a MAC PUD subheader including at least one of:

an LCID for reporting the DC PHR MAC CE using a one-octet bitmap; and

an LCID for reporting the DC PHR MAC CE using a four-octet bitmap.

13. A method for reporting power headroom by a user equipment (UE) to a next generation NodeB (gNB) in a Multi-Radio Access Technology (RAT) Dual Connectivity (MR-DC) scenario, the method comprising:

generating a Multiple Entry (ME) Power Headroom Report (PHR) MAC Control Element (CE) based on information received from a network, the ME PHR MAC CE having a fixed number of octets with cell index fields for indicating whether a power headroom (PH) for a serving cell with a corresponding cell index is reported, wherein the fixed number of octets is determined based on information received from the network; and

transmitting, by the UE, the ME PHR MAC CE to the gNB, wherein the information received from the network comprises one of a highest serving cell index (ServCellIndex) for serving cells with configured uplink, and a stop value of a secondary node serving cell index range.

14. The method of claim 13 , wherein a bit in the ME PHR MAC CE is used to indicate whether a PH of a supplemental uplink (SUL) associated with a serving cell is present in the ME PHR MAC CE, and wherein the SUL is supplemental to an original uplink (OUL) associated with the serving cell.

15. The method of claim 14 , wherein whether the PH of the SUL associated with the serving cell is present is based on at least one of:

one or more sounding reference signal (SRS) configurations for the SUL associated with the serving cell; and

one or more allocated resources for uplink data transmission on the SUL associated with the serving cell.

16. The method of claim 13 , wherein a bit in the ME PHR MAC CE is used to indicate whether one or more original uplink (OUL) PHs of serving cells are reported or one or more supplemental uplink (SUL) PHs of serving cells are reported.

17. The method of claim 13 , wherein the ME PHR MAC CE is identified by a MAC PDU subheader including at least one of:

an LCID for reporting the ME PHR MAC CE for one or more supplemental uplinks (SULs) using a single-octet bitmap; and

an LCID for reporting the ME PHR MAC CE for one or more SULs using a four-octet bitmap.

18. A user equipment (UE) configured to report power headroom to a next generation NodeB (gNB) in a Multi-Radio Access Technology (RAT)-Dual Connectivity (MR-DC) scenario, the UE comprising:

one or more non-transitory computer-readable media having computer-executable instructions embodied thereon; and

at least one processor coupled to the one or more non-transitory computer-readable media, and configured to execute the computer-executable instructions to:

generate a Multiple Entry (ME) Power Headroom Report (PHR) MAC Control Element (CE) based on information received from a network, the ME PHR MAC CE having a fixed number of octets with cell index fields for indicating whether a power headroom (PH) for a serving cell with a corresponding cell index is reported, wherein the fixed number of octets is determined based on information received from the network; and

transmit the ME PHR MAC CE to the gNB, wherein the information received from the network comprises one of a highest serving cell index (ServCellIndex) for serving cells with configured uplink, and a stop value of a secondary node serving cell index range.

19. The UE of claim 18 , wherein a bit in the ME PHR MAC CE is used to indicate whether a PH of a supplemental uplink (SUL) associated with a serving cell is present in the ME PHR MAC CE, and wherein the SUL is supplemental to an original uplink (OUL) associated with the serving cell.

20. The method of claim 19 , wherein whether the PH of the SUL associated with the serving cell is present, is based on at least one of:

one or more sounding reference signal (SRS) configurations for the SUL associated with the serving cell; and

one or more allocated resources for uplink data transmission on the SUL associated with the serving cell.

21. The UE of claim 18 , wherein a bit in the ME PHR MAC CE is used to indicate whether one or more original uplink (OUL) PHs of serving cells are reported or one or more supplemental uplink (SUL) PHs of serving cells are reported.

22. The method of claim 18 , wherein the ME PHR MAC CE is identified by a MAC PDU subheader including at least one of:

an LCID for reporting the ME PHR MAC CE for one or more supplemental uplinks (SULs) using a single-octet bitmap; and

an LCID for reporting the ME PHR MAC CE for one or more SULs using a four-octet bitmap.