Failure handling for secondary cell

Patent metadata

Field	Value
Publication number	US-12470957-B2
Application number	US-202318475801-A
Country	US
Kind code	B2
Filing date	Sep 27, 2023
Priority date	Nov 4, 2019
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

A user equipment (UE) is connected to a wireless network and operates in a carrier aggregation (CA) state that includes a first connection to a primary cell and a second connection to a secondary cell. The UE determines a beam failure has occurred for one of the first connection or the second connection and initiates a beam failure recovery (BFR) operation. The BFR operation includes transmitting, to the primary cell, a BFR Medium Access Control (MAC) Control Element (CE).

First claim

What is claimed:

1 . A method, performed by a network cell operating as a primary cell (PCell) for a user equipment (UE), the method comprising:
receiving, from the UE, a scheduling request; transmitting, to the UE, an uplink grant in response to the scheduling request; and receiving, from the UE in resources indicated by the uplink grant, a beam failure recovery (BFR) Medium Access Control (MAC) Control Element (CE) as part of a random access channel (RACH) procedure with the UE, wherein the UE triggers the RACH procedure for secondary cell (SCell) beam failure recovery (BFR).

2 . The method of claim 1 , wherein the BFR MAC-CE further comprises an identify of at least one other beam that is currently available for communication between the UE and a secondary cell (SCell).

3 . The method of claim 1 , wherein the scheduling request comprises a dedicated failure scheduling request.

4 . The method of claim 1 , wherein the scheduling request comprises a service transmission scheduling request.

5 . The method of claim 1 , further comprising:
transmitting, to the UE, an acknowledgement that the SCell BFR operation has been successfully completed.

6 . The method of claim 5 , wherein the acknowledgement comprises an uplink grant that schedules a new transmission for a same Hybrid Automatic Repeat Request (HARQ) process as a Physical Uplink Shared Channel (PUSCH) carrying the BFR MAC-CE.

7 . The method of claim 1 , wherein the BFR MAC-CE is transmitted in the uplink grant for the RACH procedure.

8 . A network cell operating as a primary cell, comprising:
a transceiver configured to communicate with a user equipment (UE); and a processor configured to perform operations comprising: receiving, from the UE, a scheduling request; transmitting, to the UE, an uplink grant in response to the scheduling request; and receiving, from the UE in resources indicated by the uplink grant, a beam failure recovery (BFR) Medium Access Control (MAC) Control Element (CE) as part of a random access channel (RACH) procedure with the UE, wherein the UE triggers the RACH procedure for secondary cell (SCell) beam failure recovery (BFR).

9 . The network cell of claim 8 , wherein the BFR MAC-CE further comprises an identify of at least one other beam that is currently available for communication between the UE and a secondary cell (SCell).

10 . The network cell of claim 8 , wherein the scheduling request comprises a dedicated failure scheduling request.

11 . The network cell of claim 8 , wherein the scheduling request comprises a service transmission scheduling request.

12 . The network cell of claim 8 , wherein the operations further comprise:
transmitting, to the UE, an acknowledgement that the SCell BFR has been successfully completed.

13 . The network cell of claim 12 , wherein the acknowledgement comprises an uplink grant that schedules a new transmission for a same Hybrid Automatic Repeat Request (HARQ) process as a Physical Uplink Shared Channel (PUSCH) carrying the BFR MAC-CE.

14 . The network cell of claim 8 , wherein the BFR MAC-CE is transmitted in the uplink grant for the RACH procedure.

15 . A processor of a network cell operating as a primary cell (PCell) for a user equipment (UE), the processor configured to:
receive, from the UE, a scheduling request; transmit, to the UE, an uplink grant in response to the scheduling request; and receive, from the UE in resources indicated by the uplink grant, a beam failure recovery (BFR) Medium Access Control (MAC) Control Element (CE) as part of a random access channel (RACH) procedure with the UE, wherein the UE triggers the RACH procedure for secondary cell (SCell) beam failure recovery (BFR).

16 . The processor of claim 15 , wherein the BFR MAC-CE further comprises an identity of at least one other beam that is currently available for communication between the UE and the SCell.

17 . The processor of claim 15 , wherein the scheduling request comprises a dedicated failure scheduling request or a service transmission scheduling request.

18 . The processor of claim 15 , wherein the processor is further configured to:
transmit, to the UE, an acknowledgement that the SCell BFR has been successfully completed.

19 . The processor of claim 18 , wherein the acknowledgement comprises an uplink grant that schedules a new transmission for a same Hybrid Automatic Repeat Request (HARQ) process as a Physical Uplink Shared Channel (PUSCH) carrying the BFR MAC-CE.

20 . The processor of claim 15 , wherein the BFR MAC-CE is transmitted in the uplink grant for the RACH procedure.

Assignees

• Apple Inc

Inventors

• Xu Fangli
• Yao Chunhai
• Rodgers Clive E
• Zhang Dawei
• Hu Haijing
• Sun Haitong
• Zeng Wei
• Chen Yuqin
• Zhang Yushu
• Wu Zhibin

Classifications

• H04W74/004

  in the uplink, i.e. towards network · CPC title

• H04B7/06964

  Re-selection of one or more beams after beam failure · CPC title

• H04W76/15

  Setup of multiple wireless link connections · CPC title

• H04L5/001

  the frequencies being arranged in component carriers · CPC title

• H04W76/19

  Connection re-establishment · CPC title