CONNECTIVITY SUPERVISION AND RECOVERY
Systems, methods, and instrumentalities are disclosed for connectivity supervision and recovery. A WTRU may supervise its capability to transmit and receive data, including in the absence of a control channel (e.g. grant-less transmission). A supervision framework may permit a WTRU to supervise, for example, quality of a feedback channel, quality of reciprocal resources and/or transmission attempts. A supervision process may be a function of a control channel structure or WTRU state. A supervision process may be associated with a quality of service. A supervision process may be based on WTRU transmission for energy/resource efficient operation. Multiple Recovery procedures may be defined. A recovery procedure may be a function of a supervision process. A recovery procedure may be optimized for low latency services. Recovery procedures may involve dedicated resources for recovery, transition to light connection, grant-less resource, etc. User plane recovery may include reuse of layer2 context, data replication to companion MAC instances, etc. Control plane recovery may use RAN paging, WTRU triggered multi-connectivity, etc. A recovery procedure for a supervision process associated with a beam process may include WTRU triggering beam training/beam refinement, etc.
1 . A wireless transmit/receive unit (WTRU), comprising:
a processor configured to:
establish at least a first supervision process and a second supervision process, each associated with one or more radio link failure (RLF) criteria and a type of transmission or communication link between a node and the WTRU,
wherein each of the established supervision process is further associated with at least one of: a bandwidth part (BWP), a beam process, a control channel, and a quality of service (QoS);
determine that a first RLF criterion associated with a first supervision process of the established supervision processes has been met; and
perform a recovery action associated with the first supervision process, in response to a determination that the first RLF criterion has been met, based on an identity of the first supervision process and a status of at least the second supervision process.
2 . The WTRU of claim 1 , wherein each of the established supervision processes comprises monitoring a predefined reference signal.
3 . The WTRU of claim 1 , wherein the type of transmission or communication link is associated with a control channel or a grant-less resource.
4 . The WTRU of claim 1 , wherein each of the established supervisory processes comprises monitoring at least one signal characteristic of the type of transmission or communication link or at least one beam characteristic.
5 . (canceled)
6 . The WTRU of claim 4 , wherein the at least one signal characteristic comprises at least one of: an average packet delay, signal quality, an average number of transmission attempts, one or more cycle redundancy check (CRC) failures, an average data rate, and a link quality considering interference.
7 . The WTRU of claim 4 , wherein the at least one beam characteristic comprises at least one of: a quality metric, an interference metric, a beam status, a transmission activity associated with a beam, and a reception activity associated with a beam.
8 . The WTRU of claim 1 , wherein the recovery action comprises at least one of: triggering beam training, triggering a different transmission type, triggering a different transmission time interval, and changing the transmission time interval.
9 . The WTRU of claim 1 , wherein each of the established supervisory processes comprises adiustinq a monitoring periodicity of a reference signal based on a periodicity of the reference signal.
10 . The WTRU of claim 1 , wherein the first RLF criterion comprises at least one of: the WTRU entering a light connected state, and activating a MAC channel.
11 . The WTRU of claim 1 , wherein the processor is configured to perform the recovery action further based on at least one of: a service affected, a failure criterion, and a failure of a previous recovery.
12 . A method of a wireless transmit/receive unit (WTRU), comprising:
establishing at least a first supervision process and a second supervision process, each associated with one or more radio link failure (RLF) criteria and a type of transmission or communication link between a node and the WTRU, wherein each of the established supervision process is further associated with at least one of: a bandwidth part (BWP), a beam process, a control channel, and a quality of service (QoS);
determining that a first RLF criterion associated with a first supervision process of the established supervision processes has been met; and
performing a recovery action associated with the first supervision process, in response to a determination that the first RLF criterion has been met, based on an identity of the first supervision process and a status of at least the second supervision process.
13 . The method of claim 12 , wherein each of the established supervision processes comprises monitoring a predefined reference signal.
14 . The method of claim 12 , wherein the type of transmission or communication link is associated with a control channel or a grant-less resource.
15 . The method of claim 12 , wherein each of the established supervisory processes comprises monitoring at least one signal characteristic of the type of transmission or communication link or at least one beam characteristic.
16 . (canceled)
17 . The method of claim 15 , wherein the at least one signal characteristic comprises at least one of: an average packet delay, signal quality, an average number of transmission attempts, one or more cycle redundancy check (CRC) failures, an average data rate, and a link quality considering interference.
18 . The method of claim 15 , wherein the at least one beam characteristic comprises at least one of: a quality metric, an interference metric, a beam status, a transmission activity associated with a beam, and a reception activity associated with a beam.
19 . The method of claim 12 , wherein the recovery action comprises at least one of: triggering beam training, triggering a different transmission type, triggering a different transmission time interval, and changing the transmission time interval.
20 . (canceled)
21 . The method of claim 12 , wherein the first RLF criterion comprises at least one of: the WTRU entering a light connected state, and activating a MAC channel.
22 . (canceled)
23 . The WTRU of claim 1 , wherein each of the established supervisory processes comprises monitoring a received quality of a downlink feedback channel associated with a grant-less resource or one or more transmission attempts.
24 . The method of claim 12 , wherein each of the established supervisory processes comprises monitoring a received quality of a downlink feedback channel associated with a grant-less resource or one or more transmission attempts.