MAC CE for beam failure recovery
Aspects for MAC CE configurations for beam failure recovery operations are disclosed. In one aspect, a method of wireless communication comprising: determining, by a user equipment (UE), a beam failure recovery for a serving cell; transmitting, by the UE, a beam failure recovery request for the serving cell; and transmitting, by the UE, a MAC CE including new beam information and including serving cell identification information multiple serving cells, including the serving cell, wherein the serving cell identification information identifies the multiple serving cells. In another aspect, the MAC CE may include bandwidth part information. Other aspects and features are also claimed and described.
1. A method of wireless communication comprising:
determining, by a user equipment (UE), a beam failure recovery for a serving cell;
transmitting, by the UE, a beam failure recovery request for the serving cell; and
transmitting, by the UE, a medium access control control element (MAC CE) including new beam information and including serving cell identification information for multiple serving cells, including the serving cell, wherein the serving cell identification information identifies the multiple serving cells, wherein the new beam information includes one or more resource ID fields, wherein the MAC CE further includes one or more indicator fields configured to indicate whether a corresponding resource ID field of the one or more resource ID fields includes one of reference signal resource information or reserve bits, and wherein when an indicator field of the one or more indicator fields has a first value, the corresponding resource ID field includes the reserve bits, and when the indicator field has a second value, the corresponding resource ID field includes the reference signal resource information.
2. The method of claim 1 , wherein the multiple serving cells comprise multiple secondary serving cells.
3. The method of claim 2 , further comprising:
determining, by the UE, multiple beam failure recoveries for the multiple secondary serving cells, including the serving cell; and
transmitting, by the UE, multiple beam failure recovery requests for the multiple secondary serving cells, wherein the serving cell identification information of the MAC CE identifies the multiple secondary serving cells.
4. The method of claim 1 , further comprising:
encoding, by the UE, the MAC CE based on one or more indicator fields of the MAC CE.
5. The method of claim 4 , wherein encoding, by the UE, the MAC CE based on the one or more indicator fields includes:
responsive to determining a configured field has a first value:
setting a corresponding resource ID field to a null value.
6. The method of claim 4 , wherein encoding, by the UE, the MAC CE based on the one or more indicator fields includes:
responsive to determining a configured field has a second value:
encoding a corresponding resource ID field to indicate the new beam information.
7. The method of claim 1 , wherein the new beam information includes a plurality of resource ID fields, each resource ID field comprising reference signal information.
8. The method of claim 1 , wherein the serving cell identification information includes a plurality of serving cell ID fields.
9. The method of claim 1 , further comprising:
determining, by the UE, a second beam failure recovery for a particular secondary serving cell;
transmitting, by the UE, a second beam failure recovery request for the particular secondary serving cell; and
transmitting, by the UE, a second MAC CE including second serving cell identification information and second new beam information for a single serving cell, wherein the second new beam information comprises beam information for a new beam that corresponds to the determined second beam failure recovery for the particular secondary serving cell.
10. An apparatus configured for wireless communication, the apparatus comprising:
at least one processor; and
a memory coupled to the at least one processor,
wherein the at least one processor is configured:
to determine, by a user equipment (UE), a beam failure recovery for a serving cell;
to transmit, by the UE, a beam failure recovery request for the serving cell; and
to transmit, by the UE, a medium access control control element (MAC CE) including new beam information and including serving cell identification information for multiple serving cells, including the serving cell, wherein the serving cell identification information identifies the multiple serving cells, wherein the new beam information includes one or more resource ID fields, and wherein the MAC CE further includes one or more indicator fields configured to indicate whether a corresponding resource ID field of the one or more resource ID fields includes one of reference signal resource information or reserve bits, and wherein when an indicator field of the one or more indicator fields has a first value, the corresponding resource ID field includes the reserve bits, and when the indicator field has a second value, the corresponding resource ID field includes the reference signal resource information.
11. The apparatus of claim 10 , wherein the new beam information includes a single resource ID field.
12. The apparatus of claim 10 , wherein the new beam information includes a plurality of resource ID fields.
13. The apparatus of claim 12 , wherein the plurality of resource ID fields include multiple resource ID fields for a single serving cell of the multiple serving cells, wherein the multiple resource ID fields for a single serving cell include a synchronization signal block (SSB) field and a non-zero power channel state information reference signal received power (NZP CSI-RS) field.
14. The apparatus of claim 13 , wherein the serving cell identification information includes a plurality of serving cell ID fields, and wherein the plurality of resource ID fields are positioned after a last serving cell ID field of the plurality of serving cell ID fields.
15. The apparatus of claim 10 , wherein the one or more indicator fields are configured to indicate a structure of the MAC CE.
16. The apparatus of claim 15 , wherein the one or more indicator fields includes a configured field, and wherein the configured field is configured to indicate if the new beam information is included in the MAC CE.
17. The apparatus of claim 16 , wherein the one or more indicator fields are configured to indicate whether a new beam information field is included in the MAC CE.
18. The apparatus of claim 10 , wherein the one or more indicator fields include a configured field for each serving cell indicated by the serving cell identification information that indicates, and wherein:
when the configured field has the second value, the corresponding resource ID field of the one or more resource ID fields indicates the reference signal resource information; or
when the configured field has the first value, the corresponding resource ID field has reserve bits and does not indicate the reference signal resource information.
19. The apparatus of claim 18 , wherein the reference signal resource information comprises synchronization signal block (SSB) information or channel state information reference signal received power (CSI-RSRP) information.
20. The apparatus of claim 10 , wherein the serving cell identification information includes a plurality of serving indicators, and wherein the one or more resource ID fields are positioned after a last serving cell indicator of the plurality of serving cell indicators.
21. A method of wireless communication comprising:
transmitting, by a base station, a transmission;
receiving, by the base station, a beam failure recovery request corresponding to the transmission; and
receiving, by the base station, a medium access control control element (MAC CE) including new beam information and including serving cell identification information for multiple serving cells, wherein the serving cell identification information identifies the multiple serving cells, wherein the new beam information includes one or more resource ID fields, and wherein the MAC CE further includes one or more indicator fields configured to indicate whether a corresponding resource ID field of the one or more resource ID fields includes one of reference signal resource information or reserve bits, and wherein when an indicator field of the one or more indicator fields has a first value, the corresponding resource ID field includes the reserve bits, and when the indicator field has a second value, the corresponding resource ID field includes the reference signal resource information.
22. The method of claim 21 , wherein the multiple serving cells comprise multiple secondary serving cells, and further comprising:
receiving, by the base station, multiple beam failure recovery requests for the multiple secondary serving cells, wherein the serving cell identification information of the MAC CE identifies the multiple secondary serving cells.
23. The method of claim 21 , further comprising:
parsing, by the base station, the MAC CE based on the one or more indicator fields of the MAC CE.
24. The method of claim 23 , wherein parsing, by the base station, the MAC CE based on the one or more indicator fields includes:
responsive to determining a configured field has a first value:
ignoring a corresponding resource ID field.
25. The method of claim 23 , wherein parsing, by the base station, the MAC CE based on the one or more indicator fields includes:
responsive to determining a configured field has a second value:
parsing a corresponding resource ID field to determine the new beam information.
26. An apparatus configured for wireless communication, the apparatus comprising:
at least one processor; and
a memory coupled to the at least one processor,
wherein the at least one processor is configured:
to transmit, by a base station, a transmission;
to receive, by the base station, a beam failure recovery request corresponding to the transmission; and
to receive, by the base station, a medium access control control element (MAC CE) including new beam information and including serving cell identification information for multiple serving cells, wherein the serving cell identification information identifies the multiple serving cells, wherein the new beam information includes one or more resource ID fields, wherein the MAC CE further includes one or more indicator fields configured to indicate whether a corresponding resource ID field of the one or more resource ID fields includes one of reference signal resource information or reserve bits, and wherein when an indicator field of the one or more indicator fields has a first value, the corresponding resource ID field includes the reserve bits, and when the indicator field has a second value, the corresponding resource ID field includes the reference signal resource information.
27. The apparatus of claim 26 , wherein the new beam information includes one or more resource ID fields.
28. The apparatus of claim 27 , wherein the one or more resource ID fields include a plurality of resource ID fields, and the wherein the plurality of resource ID fields include multiple resource ID fields for a single serving cell of the multiple serving cells.
29. The apparatus of claim 27 , wherein the serving cell identification information includes a plurality of serving cell ID fields, and wherein the one or more resource ID fields are positioned after a last serving cell ID field of the plurality of serving cell ID fields.
30. The apparatus of claim 26 , wherein the serving cell identification information includes a plurality of serving indicators, and wherein the one or more resource ID fields are positioned after a last serving cell indicator of the plurality of serving cell indicators.