Power headroom reporting with dual connectivity
Embodiments described herein relate generally to a communication between a user equipment (“UE”) and a plurality of evolved Node Bs (“eNBs”). A UE may be adapted to operate in a dual connected mode on respective wireless cells provided by first and second eNBs. The UE may be adapted to estimate respective power headroom (“PHR”) values associated with simultaneous operation on the first and second wireless cells. The UE may cause the first and second PHR estimates to be transmitted to both the first and second eNBs. The first and second eNBs may use these estimates to compute respective uplink transmission powers for the UE. Other embodiments may be described and/or claimed.
1. An apparatus for a user equipment (UE), the apparatus comprising:
a memory to store multiple power headroom (PHR) values for dual connectivity; and
one or more processors to:
generate a media access control (MAC) control element associated with the multiple power headroom (PHR) values for dual connectivity, wherein the MAC control element includes:
a first indication associated with a master cell group, the first indication corresponding to a first PHR value associated with a first wireless primary cell (PCell) of the master cell group; and
a second indication associated with a secondary cell group, the second indication corresponding to a second PHR value associated with a second wireless PCell of the secondary cell group; and
instruct the UE to transmit the MAC control element to one or more base stations.
2. The apparatus of claim 1 , wherein the first indication includes a first Type 2 PHR field to indicate the first PHR value associated with the first wireless PCell based on a first Physical Uplink Control Channel (PUCCH) transmission power, and the second indication includes a second Type 2 PHR field to indicate the second PHR value associated with the second wireless PCell based on a second PUCCH transmission power.
3. The apparatus of claim 2 , wherein the first indication includes a first Type 1 PHR field to indicate the first PHR value associated with the first wireless PCell based on a first Physical Uplink Shared Channel (PUSCH) transmission power, and the second indication includes a Type 1 PHR field to indicate the second PHR value associated with the second wireless PCell based on a second PUSCH transmission power.
4. The apparatus of claim 1 , wherein the first indication includes a first PcMAX,c field to indicate a maximum output power of the first wireless PCell, and wherein the second indication includes a second PcMAX,c field to indicate a maximum output power of the second wireless PCell.
5. The apparatus of claim 1 , wherein the one or more processors are further to monitor more than one periodic PHR timer to identify a time for transmission of the MAC control element.
6. One or more non-transitory computer-readable media comprising compute device-executable instructions, wherein the instructions, in response to execution by a processor, cause the processor to:
determine at least one duration that corresponds to at least one of more than one periodic power headroom (PHR) timers to be used by a user equipment (UE) to identify a time for transmission of information associated with multiple PHR values for dual connectivity; and
cause transmitter circuitry to transmit a signal to the UE, the signal including at least one value based on the at least one duration;
responsive to transmission of the signal, identify a received communication including a media access control (MAC) control element, wherein the MAC control element includes:
a first indication associated with a master cell group that corresponds to a first base station, the first indication corresponding to a first PHR value associated with a first wireless primary cell (PCell) of the master cell group; and
a second indication associated with a secondary cell group that corresponds to a second base station, the second indication corresponding to a second PHR value associated with a second wireless PCell of the secondary cell group.
7. The one or more non-transitory computer-readable media of claim 6 , wherein the first indication includes a first Type 2 PHR field to indicate the first PHR value associated with the first wireless PCell based on a first Physical Uplink Control Channel (PUCCH) transmission power, and the second indication includes a second Type 2 PHR field to indicate the second PHR value associated with the second wireless PCell based on a second PUCCH transmission power.
8. The one or more non-transitory computer-readable media of claim 7 , wherein the first indication includes a first Type 1 PHR field to indicate the first PHR value associated with the first wireless PCell based on a first Physical Uplink Shared Channel (PUSCH) transmission power, and the second indication includes a Type 1 PHR field to indicate the second PHR value associated with the second wireless PCell based on a second PUSCH transmission power.
9. The one or more non-transitory computer-readable media of claim 7 , wherein the first indication includes a first PcMAX,c field to indicate a maximum output power of the first wireless PCell, and wherein the second indication includes a second PcMAX,c field to indicate a maximum output power of the second wireless PCell.
10. The one or more non-transitory computer-readable media of claim 6 , wherein the instructions further cause the processor to transmit at least one of the multiple PHR values from the first base station to the second base station via an X2 interface.
11. The one or more non-transitory computer-readable media of claim 6 , wherein the instructions are further to cause the processor to determine at least one pathloss threshold value that corresponds to said at least one of said more than one periodic PHR timers, wherein the signal includes the at least one pathloss threshold value.
12. The one or more non-transitory computer-readable media of claim 6 , wherein the instructions are further to cause the processor to generate an information element to control the transmission of the information, to cause the signal to be transmitted responsive to generation of the information element.
13. The one or more non-transitory computer-readable media of claim 12 , wherein the information element comprises a MAC-MainConfig information element including a periodic PHR timer field associated with the master cell group, a PHR timer field associated with the secondary cell group, a prohibit timer field associated with the master cell group, and a prohibit timer field associated with the secondary cell group.
14. The one or more non-transitory computer-readable media of claim 13 , wherein the information element includes a master cell group pathloss change field and a secondary cell group pathloss change field.
15. A method for a user equipment (UE), the method comprising:
simultaneously operating on a first wireless primary cell (PCell), provided by a first base station of a master cell group, and a second wireless PCell, provided by a second base station of a secondary cell group;
computing a first power headroom (PHR) value associated with the first wireless PCell and a second PHR value associated with the second wireless PCell;
generating a media access control (MAC) control element, wherein the MAC control element includes:
a first indication corresponding to the first PHR value associated with the first wireless PCell; and
a second indication corresponding to the second PHR value associated with the second wireless PCell; and
transmitting the MAC control element to at least one of the first base station and the second base station.
16. The method of claim 15 , wherein the first indication includes a first Type 2 PHR field to indicate the first PHR value associated with the first wireless PCell based on a first Physical Uplink Control Channel (PUCCH) transmission power, and the second indication includes a second Type 2 PHR field to indicate the second PHR value associated with the second wireless PCell based on a second PUCCH transmission power.
17. The method of claim 16 , wherein the first indication includes a first Type 1 PHR field to indicate the first PHR value associated with the first wireless PCell based on a first Physical Uplink Shared Channel (PUSCH) transmission power, and the second indication includes a Type 1 PHR field to indicate the second PHR value associated with the second wireless PCell based on a second PUSCH transmission power.
18. The method of claim 15 , wherein the first indication includes a first PcMAX,c field to indicate a maximum output power of the first wireless PCell, and wherein the second indication includes a second PcMAX,c field to indicate a maximum output power of the second wireless PCell.
19. The method of claim 15 , further comprising monitoring more than one periodic PHR timer to identify a time for transmission of the MAC control element.
20. The method of claim 15 , further comprising transmitting the MAC control element to the first base station.