Method and device for fast master cell group link recovery in wireless communications
Method and device in a communication node for wireless communications. A communication node determines that a physical-layer problem occurs in a first serving cell; as a response to determining that the physical-layer problem occurs in the first serving cell, starts a first timer; determines that a first condition set is satisfied; as a response to the first condition set being satisfied, transmits a first signaling; as a response to the first condition set being satisfied, starts a second timer and stops the first timer; when the second timer is in a running state, monitors a second signaling; the first condition set comprises that an RLF occurs in the first serving cell and the second timer is configured; the second timer is associated with the first serving cell; the first signaling is used to initiate a radio connection recovery; and the second signaling is used to update a radio connection.
1 . A user equipment (UE), comprising:
a transmitter; and
a receiver,
wherein the UE is configured to:
on a condition that N310 out-of-sync indications are received from a lower layer for a first cell:
start a T310 timer,
on a condition that a T316 timer is configured and a radio link failure occurs while a T310 timer is running:
transmit a master cell group (MCG) failure information (MCGFailureInformation) message for fast MCG link recovery,
stop the T310 timer, and
after the T310 timer is stopped, start the T316 timer, and
during a time when the T316 timer is running, receive an RRCRelease message or an RRCConnectionReconfiguration message including reconfigurationWithSync.
2 . The UE according to claim 1 , wherein the UE is configured to transmit the MCGFailureInformation message, stop the T310 timer and start the T316 timer on a condition that:
the radio link failure occurs for the first cell,
the UE is configured with a split SRB1 or an SRB3,
the first cell and a second cell are not suspended, and
the T316 timer is not running.
3 . The UE according to claim 1 , wherein the UE is configured to determine that the radio link failure occurred in the first cell on a condition that:
the T310 timer expires,
a timer T312 expires,
an indication of reaching a maximum retransmission number is received from an MCG RLC,
an indication of reaching a maximum retransmission number of an SRB or a DRB is received from an MCG RLC,
an indication of a Random Access (RA) problem is received from an MCG Medium Access Control (MAC) and none of timers T300, T301, T304, T311 and T319 is running, or
an indication of an RA problem is received from an MCG MAC and none of timers T300, T301, T304, and T311 is running.
4 . The UE according to claim 1 , wherein:
a signaling radio bearer of the MCGFailureInformation message is SRB1 or SRB3, and;
a logical channel bearing the MCGFailureInformation message includes a Dedicated Control Channel (DCCH), and the MCGFailureInformation message includes a ULInformationTransferMRDC message.
5 . The UE according to claim 1 , wherein the occurrence of the radio link failure is unrelated to the T310 timer.
6 . The UE according to claim 1 , wherein the UE is configured to:
on condition that N310 out-of-sync indications are received for a second cell, start a third timer, wherein transmitting the MCGFailureInformation message does not affect a timing of the third timer.
7 . The UE according to claim 1 , wherein the UE is configured to stop the T316 timer and transmit a confirmation message on a condition that the RRCConnectionReconfiguration message is received.
8 . The UE according to claim 7 , wherein a signaling radio bearer of the confirmation message includes an SRB1 or an SRB3, a logical channel bearing the confirmation message includes a DCCH, and the confirmation message is an RRCConnectionReconfigurationComplete message.
9 . The UE-according to claim 1 , wherein: the UE is configured to transmit an RRCReestablishmentRequest message or an RRCConnectionReestablishmentRequest message in response to expiration of the T316 timer.
10 . The UE according to claim 1 , wherein: the RRCConnectionReconfiguration message indicates an expiration value of the T310 timer and an expiration value of the T316 timer.
11 . The UE according to claim 10 , wherein a signaling radio bearer of the RRCConnectionReconfiguration message is SRB1 or SRB3.
12 . The UE according to claim 1 , wherein the T310 timer is not started on a condition that the T316 timer is running.
13 . The UE according to claim 12 , wherein the T310 timer is started on a condition that the T316 timer is not running.
14 . A method, comprising:
receiving N310 out-of-sync indications from a lower layer for a first cell, and starting a T310 timer,
wherein a T316 timer is configured and a radio link failure occurs while the T310 timer is running;
transmitting a master cell group (MCG) failure information (MCGFailureInformation) message for fast MCG link recovery,
stopping the T310 timer, and
starting a T316 timer, wherein the T316 timer is started after the T310 timer is stopped; and
during a time when the T316 timer is running, receiving an RRCRelease message or an RRCConnectionReconfiguration message including reconfigurationWithSync.