Transmission of buffer status reports on multiple component carriers
The present disclosure generally relates to a methods, apparatus, and computer readable medium for implementing the methods for transmitting multi-bit SR (SRs) from a user equipment (UE). The UE may receive, from a base station, a radio resource control (RRC) message. The RRC message may indicate that uplink component carriers (CCs) of the UE are to be assigned to a plurality of uplink CC groups. Upon receipt of the RRC, the UE may assign the uplink CCs to the plurality of uplink CC groups. A multi-bit SR may be generated for each group of the plurality of uplink CC groups. The UE may transmit the multi-bit SR generated for each group of the plurality of uplink CC groups to the base station. Multi-bit SR transmission across different CCs may reduce latency in uplink grant and improve data transmission time.
1. A method of transmitting multi-bit scheduling requests (SRs) from a user equipment (UE); comprising:
receiving, at the UE, a radio resource control (RRC) message from a base station, wherein the RRC message indicates that uplink component carriers (CCs) of the UE are to be assigned to a plurality of uplink CC groups, wherein the plurality of uplink CC groups includes a first uplink CC group and a second uplink CC group;
assigning the uplink CCs to the plurality of uplink CC groups;
generating, at the UE, a multi-bit SR for each group of the plurality of uplink CC groups, wherein the generating includes generating a first multi-bit SR for the first uplink CC group and a second multi-bit SR for the second uplink CC group, wherein a first number of bits of the first multi-bit SR is different from a second number of bits of the second multi-bit SR;
mapping each logical channel group (LCG) of a plurality of LCGs at the UE to an uplink CC of the plurality of uplink CCs; and
transmitting, from the UE, the multi-bit SR generated for each group of the plurality of uplink CC groups to the base station.
2. The method of claim 1 , wherein the mapping is updated in a semi-static or a dynamic manner.
3. The method of claim 2 , wherein the mapping is updated in the semi-static manner via a second RRC message.
4. The method of claim 2 , wherein the mapping is updated in the semi-static manner, and wherein the updating is based on a scheduler load associated with a corresponding uplink CC.
5. The method of claim 2 , wherein the mapping is updated in the dynamic manner when all physical uplink control channel (PUCCH)/physical uplink shared channel (PUSCH) transmissions are scheduled by one downlink control information (DCI).
6. The method of claim 1 , further comprising:
dynamically updating, at the UE, a number of bits of a multi-bit SR, wherein the updating is based on one or more of an assigned physical uplink control channel (PUCCH), a PUCCH format, a PUCCH assignment size, or types or sizes of other uplink control information (UCI) payloads multiplexed together with the multi-bit SR on PUCCH, or sizes of other uplink control information (UCI) payloads multiplexed together with the multi-bit SR on PUCCH, or any combination thereof.
7. The method of claim 1 , wherein a size of the multi-bit SR is represented by the function
X =ceil(log 2( K+ 1))
wherein K is a number of physical uplink control channel (PUCCH) resources and X is a number of SR bits.
8. The method of claim 7 , wherein the K PUCCH resources are ordered in increasing size of corresponding SR resources, and wherein an index of an ordered PUCCH resource ID is obtained from X bits when SR is triggered.
9. The method of claim 7 , wherein the function applies when UCI transmitted by a UE on a PUCCH in a slot of format 2, 3, or 4 overlaps in time with K configured PUCCH resources that overlap in time.
10. The method of claim 1 , wherein the generated multi-bit SR includes a buffer status report (BSR).
11. A method of wireless communications by a user equipment (UE), comprising:
receiving, at the UE, a radio resource control (RRC) message from a base station, the RRC message includes uplink component carriers (CCs) information relating to a plurality of uplink CCs;
generating, at the UE, one of a plurality of multi-bit scheduling requests (SRs) for each of the plurality of uplink CCs;
dynamically updating a number of bits in at least one of the plurality of multi-bit SRs; and
transmitting, from the UE, the plurality of multi-bit SRs separately via a plurality of physical uplink control channel (PUCCH) resources of the plurality of uplink CCs to the base station, wherein at least a portion of the plurality of PUCCH resources overlap in time.
12. The method of claim 11 , wherein at least two of the plurality of multi-bit SRs include different numbers of bits.
13. The method of claim 11 , wherein the dynamically updating the number of bits in the at least one of the plurality of multi-bit SRs further includes updating based on one or more of a PUCCH format of PUCCH resource of the plurality of PUCCH resources associated with the at least one of the plurality of multi-bit SRs, a PUCCH assignment size of the PUCCH resource of the plurality of PUCCH resources associated with the at least one of the plurality of multi-bit SRs, or a type of uplink control information (UCI), or a size of the UCI.
14. The method of claim 11 , wherein the plurality of PUCCH resources is ordered in increasing size of the corresponding multi-bit SR.
15. The method of claim 11 , wherein at least one of the plurality of multi-bit SRs includes a buffer status report.
16. The method of claim 11 , wherein the transmission of the plurality of multi-bit SRs is triggered by one or more downlink control information (DCI).
17. A method of wireless communications by a user equipment (UE), comprising:
receiving, at the UE, a radio resource control (RRC) message from a base station, wherein the RRC message indicates that uplink component carriers (CCs) of the UE are to be assigned to a plurality of uplink CC groups;
assigning the uplink CCs to the plurality of uplink CC groups;
generating, at the UE, a multi-bit scheduling request (SR) for each group of the plurality of uplink CC groups;
dynamically updating a number of bits in at least one the multi-bit SRs; and
transmitting, from the UE, the multi-bit SR generated for each group of the plurality of uplink CC groups via a plurality of physical uplink control channel (PUCCH) resources associated with the plurality of uplink CC groups to the base station, wherein at least a portion of the plurality of PUCCH resources overlap in time.
18. The method of claim 17 , wherein at least two of the multi-bit SRs include different numbers of bits.
19. The method of claim 17 , wherein the dynamically updating the number of bits in at least one the multi-bit SRs further includes updating based on one or more of a PUCCH format of PUCCH resource of the plurality of PUCCH resources associated with the at least one of the multi-bit SRs, a PUCCH assignment size of the PUCCH resource of the plurality of PUCCH resources associated with the at least one of the multi-bit SRs, or a type of uplink control information (UCI), or a size of the UCI.
20. The method of claim 17 , wherein the plurality of PUCCH resources is ordered in increasing size of the corresponding multi-bit SR.
21. The method of claim 17 , wherein at least one of the multi-bit SRs includes a buffer status report.
22. The method of claim 17 , wherein the transmission of the multi-bit SRs is triggered by one or more downlink control information (DCI).
23. A user equipment (UE), comprising:
a memory;
a processor coupled to the memory, the memory and the processor configured to:
receive a radio resource control (RRC) message from a base station, the RRC message including uplink component carriers (CCs) information relating to a plurality of uplink CCs;
generate one of a plurality of multi-bit scheduling requests (SRs) for each of the plurality of uplink CCs;
dynamically update a number of bits in at least one of the plurality of multi-bit SRs; and
transmit the plurality of multi-bit SRs separately via a plurality of physical uplink control channel (PUCCH) resources of the plurality of uplink CCs to the base station, wherein at least a portion of the plurality of PUCCH resources overlap in time.
24. The UE of claim 23 , wherein at least two of the plurality of multi-bit SRs include different numbers of bits.
25. The UE of claim 23 , wherein to dynamically update the number of bits in the at least one of the plurality of multi-bit SRs, the memory and the processor are configured to update, based on one or more of a PUCCH format of PUCCH resource of the plurality of PUCCH resources associated with the at least one of the plurality of multi-bit SRs, a PUCCH assignment size of the PUCCH resource of the plurality of PUCCH resources associated with the at least one of the plurality of multi-bit SRs, or a type of uplink control information (UCI), or a size of the UCI.
26. The UE of claim 23 , wherein the plurality of PUCCH resources is ordered in increasing size of the corresponding multi-bit SR.
27. The UE of claim 23 , wherein at least one of the plurality of multi-bit SRs includes a buffer status report.
28. The UE of claim 23 , wherein the memory and the processor being configured to transmit the plurality of multi-bit SRs is triggered by one or more downlink control information (DCI).
29. A user equipment (UE), comprising:
a memory;
a processor coupled to the memory, the memory and the processor configured to:
receive a radio resource control (RRC) message from a base station, wherein the RRC message indicates that uplink component carriers (CCs) of the UE are to be assigned to a plurality of uplink CC groups;
assign the uplink CCs to the plurality of uplink CC groups;
generate a multi-bit scheduling request (SR) for each group of the plurality of uplink CC groups;
dynamically update a number of bits in at least one the multi-bit SRs; and
transmit the multi-bit SR generated for each group of the plurality of uplink CC groups via a plurality of physical uplink control channel (PUCCH) resources associated with the plurality of uplink CC groups to the base station, wherein at least a portion of the plurality of PUCCH resources overlap in time.
30. The UE of claim 29 , wherein at least two of the multi-bit SRs include different numbers of bits.
31. The UE of claim 29 , wherein to dynamically update the number of bits in the at least one of the plurality of multi-bit SRs, the memory and the processor are configured to update, based on one or more of a PUCCH format of PUCCH resource of the plurality of PUCCH resources associated with the at least one of the multi-bit SRs, a PUCCH assignment size of the PUCCH resource of the plurality of PUCCH resources associated with the at least one of the multi-bit SRs, or a type of uplink control information (UCI), or a size of the UCI.
32. The UE of claim 29 , wherein the plurality of PUCCH resources is ordered in increasing size of the corresponding multi-bit SR.
33. The UE of claim 29 , wherein at least one of the multi-bit SRs includes a buffer status report.
34. The UE of claim 29 , wherein the memory and the processor being configured to transmit the plurality of multi-bit SRs is triggered by one or more downlink control information (DCI).