Granted Patent B2

US 12,402,193 · App. 18/004,367 · Granted Aug 26, 2025

Inventors: Lianhai Wu (Chaoyang, CN); Haiming Wang (Xicheng District, CN)

Assignee: Lenovo (Beijing) Limited

H04W76/20H04W36/18H04W36/305H04W76/30

Abstract

Claims (69)

1. A user equipment (UE), comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the UE to:

receive a radio resource control (RRC) reconfiguration message, wherein the RRC reconfiguration message includes dual active protocol stack (DAPS) configuration information and a reconfiguration with synchronization information element;

synchronize to a target master node (MN);

synchronize, in response to a bearer associated with a secondary cell group (SCG) being configured, to a target secondary node (SN); and

initiate, upon detecting a radio link failure (RLF) of a target master cell group (MCG) and before releasing a source connection for the MCG or the SCG, a fast MCG link recovery procedure during a DAPS handover procedure.

2. The UE of claim 1 , wherein the at least one processor is configured to cause the UE to detect the RLF before receiving a second RRC reconfiguration message from a target connection indicating to release the source connection.

3. The UE of claim 1 , wherein the at least one processor is configured to cause the UE to:

upon initiation of the fast MCG link recovery procedure, in response to one or more DAPS bearers being configured:

release source special cell (SpCell) configuration information; and

release medium access control (MAC) configuration information of the source connection.

4. The UE of claim 1 , wherein the at least one processor is configured to cause the UE to:

upon initiation of the fast MCG link recovery procedure, in response to one or more DAPS bearers being configured:

release physical channel configuration information for a source SpCell.

5. The UE of claim 1 , wherein the at least one processor is configured to cause the UE to:

upon initiation of the fast MCG link recovery procedure, in response to one or more DAPS bearers being configured:

reset MAC configuration information of the source connection and release the MAC configuration information; and

discard access stratum (AS) security keys used in a source SpCell.

6. The UE of claim 1 , wherein the at least one processor is configured to cause the UE to:

upon initiation of the fast MCG link recovery procedure, in response to one or more DAPS bearers being configured:

for each DAPS bearer of the one or more DAPS bearers:

release one or more radio link control (RLC) entities and an associated logical channel for a source SpCell; and

reconfigure a packet data convergence protocol (PDCP) entity and release DAPS configuration information of the each DAPS bearer.

7. The UE of claim 1 , wherein the at least one processor is configured to cause the UE to:

upon initiation of the fast MCG link recovery procedure, in response to a DAPS bearer being configured and the DAPS bearer being a signaling radio bearer (SRB):

release a PDCP entity for a source SpCell; and

release a RLC entity and an associated logical channel for the source SpCell.

8. The UE of claim 1 , wherein the at least one processor is configured to cause the UE to:

transmit, in response to initiation of the fast MCG link recovery procedure, a MCG failure information message to the target MN,

wherein the MCG failure information message includes a channel status of a source primary cell (PCell).

9. The UE of claim 8 , wherein the channel status of the source PCell represents one of:

a timer associated with a physical layer problem is running; or

the timer associated with the physical layer problem is not started.

10. The UE of claim 8 , wherein the at least one processor is configured to cause the UE to:

receive a response from the target MN,

wherein the response includes a second RRC reconfiguration message, and the second RRC reconfiguration message includes one of: a fallback indication, a handover command, or an indication to release the source connection.

11. The UE of claim 10 , wherein the at least one processor is configured to cause the UE to:

release, in response to the second RRC reconfiguration message including the fallback indication, configuration information of a target connection and reset MAC configuration information of the target connection.

12. The UE of claim 10 , wherein the at least one processor is configured to cause the UE to:

resume, in response to the second RRC reconfiguration message including the fallback indication, one or more suspended SRBs in the source connection and revert back to configuration information used in the source connection; and

transmit a fallback complete message.

13. The UE of claim 10 , wherein the at least one processor is configured to cause the UE to:

release, in response to the second RRC reconfiguration message including the indication to release the source connection, source special cell (SpCell) configuration information and reset MAC configuration information of the source connection.

14. A user equipment (UE), comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the UE to:

receive dual connectivity (DC) configuration information;

receive a first radio resource control (RRC) reconfiguration message, wherein the first RRC reconfiguration message includes dual active protocol stack (DAPS) configuration information and a reconfiguration with synchronization information element;

perform a random access procedure to access a target cell of a master cell group (MCG) or a secondary cell group (SCG); and

receive, in response to the random access procedure, a second RRC reconfiguration message, wherein the second RRC reconfiguration message includes an indication to release a source connection for the MCG or the SCG.

15. The UE of claim 14 , based on the indication, the at least one processor is configured to cause the UE to:

reset, in response to the SCG being configured, medium access control (MAC) configuration information of the source connection for the SCG.

16. The UE of claim 14 , based on the indication, the at least one processor is configured to cause the UE to:

release, in response to each radio link control (RLC) bearer being associated with SCG configuration information, the each RLC bearer and a corresponding logical channel.

17. The UE of claim 14 , based on the indication, the at least one processor is configured to cause the UE to:

release, in response to the SCG being configured, SCG configuration information.

18. The UE of claim 14 , based on the indication, the at least one processor is configured to cause the UE to:

release secondary cells (SCell) configuration information in the SCG.

19. A method performed by a user equipment (UE), the method comprising:

receiving a radio resource control (RRC) reconfiguration message, wherein the RRC reconfiguration message includes dual active protocol stack (DAPS) configuration information and a reconfiguration with synchronization information element;

synchronizing to a target master node (MN);

synchronizing, in response to a bearer associated with a secondary cell group (SCG) being configured, to a target secondary node (SN); and

initiating, upon detecting a radio link failure (RLF) of a target master cell group (MCG) and before releasing a source connection for the MCG or the SCG, a fast MCG link recovery procedure during a DAPS handover procedure.

20. A method performed by a user equipment (UE), the method comprising:

receiving dual connectivity (DC) configuration information;

receiving a first radio resource control (RRC) reconfiguration message, wherein the first RRC reconfiguration message includes dual active protocol stack (DAPS) configuration information and a reconfiguration with synchronization information element;

performing a random access procedure to access a target cell of a master cell group (MCG) or a secondary cell group (SCG); and

receiving, in response to the random access procedure, a second RRC reconfiguration message, wherein the second RRC reconfiguration message includes an indication to release a source connection for the MCG or the SCG.

Assignments (1)

Continuity (1)

References Cited (14)