Methods and systems for secondary cell beam recovery
Some embodiments of this disclosure include systems, apparatuses, methods, and computer-readable media for use in a wireless network for configuring and implementing secondary cell beam failure recovery procedures. For example, some embodiments are directed to a user equipment (UE) that includes radio front end circuitry and processor circuitry coupled to the radio front end circuitry. The processor circuitry can be configured to detect that a first beam associated with a secondary cell (SCell) is misaligned. The first beam is associated with a first reference signal (RS). The processor circuitry can further be configured to configure a beam failure recovery (BFR) procedure for the SCell and perform the BFR procedure to replace the first beam with a second beam, wherein the second beam is associated with the SCell.
1. A user equipment (UE), comprising:
a memory configured to store program instructions; and
a processor, upon executing the program instructions, configured to:
transmit, to a base station, a beam failure recovery request (BFRQ) to indicate an index of a secondary cell (SCell) that is experiencing a beam misalignment and one or more recommended beam indices with a reference signal received power (RSRP) above a threshold configured for a beam failure recovery (BFR) procedure;
receive, from the base station, a downlink (DL) media access control (MAC) control element (CE); and
perform the BFR procedure for the SCell based on the received DL MAC CE.
2. The UE of claim 1 , wherein the processor is configured to transmit the BFRQ using an uplink (UL) MAC CE.
3. The UE of claim 2 , wherein the UL MAC CE is identified by a MAC protocol data unit (PDU) sub header with a logical channel identifier (LCID).
4. The UE of claim 3 , wherein the MAC PDU sub header includes a field indicating an identity of a Serving Cell with the beam misalignment for which the UL MAC CE applies.
5. The UE of claim 3 , wherein the MAC PDU sub header includes a field indicating an UL bandwidth part (BWP) for which the MAC CE applies.
6. The UE of claim 3 , wherein the MAC PDU sub header includes a plurality of fields for indicating the one or more recommended beam indices with the RSRP above the threshold.
7. The UE of claim 1 , wherein the processor is configured to transmit the BFRQ in a primary cell (PCell) and an SCell supporting uplink (UL) transmission.
8. A method, comprising:
transmitting, by a user equipment (UE) and to a base station, a beam failure recovery request (BFRQ) to indicate an index of a secondary cell (SCell) that is experiencing a beam misalignment and one or more recommended beam indices with a reference signal received power (RSRP) above a threshold configured for a beam failure recovery (BFR) procedure;
receiving, from the base station, a downlink (DL) media access control (MAC) control element (CE); and
performing the BFR procedure for the SCell based on the received DL MAC CE.
9. The method of claim 8 , further comprising transmitting the BFRQ using an uplink (UL) MAC CE.
10. The method of claim 9 , wherein the UL MAC CE is identified by a MAC protocol data unit (PDU) sub header with a logical channel identifier (LCID).
11. The method of claim 10 , wherein the MAC PDU sub header includes a field indicating an identity of a Serving Cell with the beam misalignment for which the UL MAC CE applies.
12. The method of claim 10 , wherein the MAC PDU sub header includes a field indicating an UL bandwidth part (BWP) for which the MAC CE applies.
13. The method of claim 10 , wherein the MAC PDU sub header includes a plurality of fields for indicating the one or more recommended beam indices with the RSRP above the threshold.
14. The method of claim 8 , further comprising transmitting the BFRQ in a primary cell (PCell) and an SCell supporting uplink (UL) transmission.
15. A base station, comprising:
a memory configured to store program instructions; and
a processor, upon executing the program instructions, configured to:
receive, from a user equipment (UE), a beam failure recovery request (BFRQ) to indicate an index of a secondary cell (SCell) that is experiencing a beam misalignment and one or more recommended beam indices with a reference signal received power (RSRP) above a threshold configured for a beam failure recovery (BFR) procedure; and
transmit, to the UE, a downlink (DL) media access control (MAC) control element (CE), wherein the DL MAC CE is used to perform the BFR procedure for the SCell.
16. The base station of claim 15 , wherein the processor is further configured to reconfigure transmission configuration indication (TCI) states of control channel resource sets (CORESET) based on the received BFRQ.
17. The base station of claim 15 , wherein the processor is configured to receive the BFRQ in a primary cell (PCell) and an SCell supporting uplink (UL) transmission.
18. The base station of claim 15 , wherein the processor is configured to receive the BFRQ using an up link (UL) MAC CE.
19. The base station of claim 18 , wherein the UL MAC CE is identified by a MAC protocol data unit (PDU) sub header with a logical channel identifier (LCID).
20. The base station of claim 19 , wherein the MAC PDU sub header comprises:
a first field indicating an identity of a Serving Cell with the beam misalignment for which the UL MAC CE applies;
a second field indicating an UL bandwidth part (BWP) for which the MAC CE applies; and
a plurality of fields for indicating the one or more recommended beam indices with the RSRP above the threshold.