Systems and methods for beam failure recovery for multi-DCI mode

1. A non-transitory computer-readable storage medium for a user equipment (UE) to perform beam failure recovery (BFR) in a multiple Downlink Control Information (mDCI) mode, the non-transitory computer-readable storage medium including instructions that when executed by a computer, cause the computer to:

receive, by the UE, a Downlink Reference Signal (DL RS) set from a next generation Node B (gNB), the DL RS set associated with a link between the UE and the gNB and indicating beam failure detection (BFD) is to be performed for the link, the DL RS set received periodically by the UE from the gNB, wherein the DL RS set corresponds to one or more CORESETs having a same CORESET-poolIndex value;

perform, by the UE, a beam failure detection (BFD) for the link using the DL RS set, the BFD determining a beam failure for the link by determining that a block error ratio (BLER) for the link is larger than a BLER threshold;

perform, by the UE, a candidate beam detection (CBD) for the link, the CBD determining a candidate beam for the link by determining a beam having a reference signal receiving power (RSRP) that is larger than an RSRP threshold; and

transmit, by the UE, a beam failure recovery request (BFRQ) indicating the link to the gNB.

2. The non-transitory computer readable storage medium of claim 1 , wherein the DL RS set includes a DL RS that is a Channel State Information Reference Signal (CSI-RS) or a synchronization signal block (SSB) indicating BFD is to be performed for the link.

3. The non-transitory computer readable storage medium of claim 2 , wherein the DL RS is configured by radio resource control (RRC) signaling.

4. The non-transitory computer readable storage medium of claim 1 , wherein the non-transitory computer-readable storage medium includes instructions that cause the computer to:

receive, by the UE, an additional DL RS set from the gNB, the additional DL RS set associated with the link and configuring the UE for the CBD, the additional DL RS set received periodically by the UE from the gNB.

5. The non-transitory computer readable storage medium of claim 4 , wherein the additional DL RS set corresponds to one or more CORESETs having the same CORESET-poolIndex value.

6. The non-transitory computer readable storage medium of claim 4 , wherein the additional DL RS set includes a DL RS that is a CSI-RS or a SSB indicating CBD is to be performed for the link.

7. The non-transitory computer readable storage medium of claim 6 , wherein the non-transitory computer-readable storage medium includes instructions that cause the computer to:

determine, by the UE, that the DL RS of the additional DL RS set is not configured by a gNB; and

use, by the UE, a default DL RS, wherein the default DL RS is an SSB from an initial bandwidth part or a current bandwidth part and indicates CBD for the link.

8. The non-transitory computer readable storage medium of claim 1 , wherein the BFRQ is transmitted via a Media Access Control Control Element (MAC CE) that includes a failed CORESET-poolIndex or DL RS set index corresponding to the link.

9. The non-transitory computer readable storage medium of claim 1 , wherein the BFRQ is transmitted using a physical random access channel (PRACH), wherein the UE is configured with a PRACH resource associated with a DL RS for the CBD of the link, the PRACH resource belonging to a group of resources for the same CORESET-poolIndex value.

10. The non-transitory computer readable storage medium of claim 1 , wherein the BFRQ is transmitted using multi-bit PUCCH resources, wherein each PUCCH resource of the PUCCH resources is associated with the same CORESET-poolIndex value, and wherein each PUCCH resource includes a failed CORESET-poolIndex or DL RS set index corresponding to the link.

11. The non-transitory computer readable storage medium of claim 1 , wherein the non-transitory computer-readable storage medium includes instructions that cause the computer to:

receive, by the UE, a response regarding the BFRQ from the gNB; and

apply, by the UE, the candidate beam to one or more CORESETs corresponding to a failed CORESET-poolIndex or DL RS set index corresponding to the link.

12. The non-transitory computer readable storage medium of claim 1 , wherein the BFD and the CBD are performed sequentially.

13. The non-transitory computer readable storage medium of claim 1 , wherein the BFD and the CBD are performed simultaneously.

14. The non-transitory computer readable storage medium of claim 1 , wherein the non-transitory computer-readable storage medium includes instructions that cause the computer to:

receive, at the UE, control signaling from the gNB that enables multi-DCI BFR.

15. The non-transitory computer readable storage medium of claim 14 , wherein the control signaling is RRC signaling.

16. The non-transitory computer readable storage medium of claim 14 , wherein the control signaling includes a plurality of DL RS sets configured for BFR and wherein the non-transitory computer-readable storage medium includes instructions that cause the computer to:

determine multi-DCI BFR is enabled due to the presence of the plurality of DL RS sets configured for BFR.

17. A method for beam failure recovery (BFR) in a multiple Downlink Control Information (mDCI) mode, the method comprising:

receiving, by a UE, a Downlink Reference Signal (DL RS) set from a next generation Node B (gNB), the DL RS set associated with a link between the UE and the gNB and indicating beam failure detection (BFD) is to be performed for the link, the DL RS set received periodically by the UE from the gNB, wherein the DL RS set corresponds to one or more CORESETs having a same CORESET-poolIndex value;

performing, by the UE, a beam failure detection (BFD) for the link using the DL RS set, the BFD determining a beam failure for the link by determining that a block error ratio (BLER) for the link is larger than a BLER threshold;

performing, by the UE, a candidate beam detection (CBD) for the link, the CBD determining a candidate beam for the link by determining a beam having a reference signal receiving power (RSRP) that is larger than an RSRP threshold; and

transmitting, by the UE, a beam failure recovery request (BFRQ) indicating the link to the gNB.

18. An apparatus for a user equipment (UE) to perform beam failure recovery (BFR) in a multiple Downlink Control Information (mDCI) mode, the apparatus comprising:

a processor; and

a memory storing instructions that, when executed by the processor, configure the apparatus to:

receive, by the UE, a Downlink Reference Signal (DL RS) set from a next generation Node B (gNB), the DL RS set associated with a link between the UE and the gNB and indicating beam failure detection (BFD) is to be performed for the link, the DL RS set received periodically by the UE from the gNB, wherein the DL RS set corresponds to one or more CORESETs having a same CORESET-poolIndex value;

perform, by the UE, a beam failure detection (BFD) for the link using the DL RS set, the BFD determining a beam failure for the link by determining that a block error ratio (BLER) for the link is larger than a BLER threshold;

perform, by the UE, a candidate beam detection (CBD) for the link, the CBD determining a candidate beam for the link by determining a beam having a reference signal receiving power (RSRP) that is larger than an RSRP threshold; and

transmit, by the UE, a beam failure recovery request (BFRQ) indicating the link to the gNB.