Abstract: A method performed by a wireless transmit/receive unit (WTRU) may include receiving a configuration message including timing information for monitoring at least a subset of a plurality of beams to receive a set of synchronization signals and receiving the set of synchronization signals based on the timing information. The received set of synchronization signals include a primary synchronization signal and a secondary synchronization signal. The method may include receiving a reference signal along with a physical broadcast channel (PBCH) transmission. The reference signal comprises a sequence that is derived from an index associated with one of the at least the subset of beams and associated with the received set of synchronization signals. The method may include transmitting a random access channel (RACH) transmission. The RACH transmission includes a preamble sequence corresponding to the one of the subset of the plurality of beams.

Abstract: Methods to perform, maintain and report measurements on a transmission-reception point (TRP) using limited reference signal transmission are described herein. The mobility measurement reports may utilize physical channels. Methods to obtain measurements on neighbor TRPs using limited RS transmissions are also described herein. Random-Access procedures to enable the addition of a neighbor TRP or handover without requiring higher layer signaling (and possibly without an interface between source and target TRP) are also described herein. New triggers to perform RA in order to decrease handover latency are also described herein. Wireless Transmit/Receive Unit (WTRU) behavior upon receiving RAR from multiple possible TRPs are also described herein. For example, a WTRU may store RAR information and use it later in an interrupted RA procedure.

Abstract: 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.

Abstract: Method, apparatus and systems are disclosed. In one representative embodiment, a method may be implemented by a wireless transmit/receive unit (WTRU) for communication via a network access point (NAP). The method may include the WTRU receiving from the NAP a set of preambles and corresponding propagation delay related thresholds and determining propagation delay related information associated with a distance between the WTRU and the NAP or a location in a coverage of the NAP. The method may further include selecting a subset of preambles from the set of preambles based on the determined propagation delay related information, randomly selecting a preamble from the selected subset of preambles, and sending the randomly selected preamble to the NAP.

Abstract: A WTRU may be configured to perform radio link monitoring (RLM) based on RLM reference signals (RLM-RSs) transmitted in a cell operating in an unlicensed spectrum. The WTRU may evaluate a radio link failure (RLF) status for the cell using a first RLM criteria based on the RLM-RSs. A transmission instance of the RLM-RSs may be skipped, for example, due to a listen before talk (LBT) failure at a gNodeB (gNB). The WTRU may adapt or change the first RLM criteria and/or evaluate the RLF status of the cell operating in the unlicensed spectrum using a second RLM criteria based on determining that the transmission instance of the RLM-RSs was skipped. The first RLM criteria may correspond to a first RLM process that utilizes a first set of RLM parameters. The second RLM criteria may correspond to a second RLM process that utilizes a second set of RLM parameters.

Abstract: A wireless transmit-receive unit (WTRU) may be configured to perform one or more actions. The WTRU may be configured to receive a handover command. The WTRU may be configured to connect to a target cell and receive one or more packets from the target cell. The WTRU may be configured to receive one or more packets from a source cell. The WTRU may be configured to determine, based on at least one of the received one or more packets from the source cell or the received one or more packets from the target cell, that there are no missing packets. The WTRU may be configured to release, based on the determination that there are no missing packets, a resource associated with the source cell.

Abstract: Methods, devices and systems are provided for performing a random access (RA) procedure. A wireless transmit/receive unit (WTRU) may be configured to receive RA resource sets, where each of the RA resource sets is associated with a node-B directional beam, select an RA resource set from among the RA resource sets, and initiate an RA procedure based on the selected RA resource set. The RA procedure may include selecting multiple preambles which include a preamble for each resource of a plurality of resources corresponding to the selected RA resource set. The WTRU may be configured to sequentially transmit the selected multiple preambles in sequential RA transmissions, and may be configured to receive, from a node-B, in response to the RA transmissions, at least one RA response (RAR), where each of the received at least one RAR corresponds to one of the transmitted multiple preambles.

Abstract: A wireless transmit/receive unit (WTRU) may be configured to measure a downlink quality associated with at least one first beam. The WTRU may be configured to determine whether the measured downlink quality associated with the at least one first beam is below a threshold value. The WTRU may be configured to receive at least one control channel transmission using a determined second beam, based on, in part, a determination that the measured downlink quality associated with the at least one first beam is below the threshold value. The determined second beam used to receive the at least one control channel transmission may be a same beam that is used to receive an associated data channel transmission. The determined second beam may be from a set of beams. The set of beams may be received via higher layer signaling.

Abstract: A method and apparatus for receiving a broadcast configuration indicating when a change in a RAN function termination occurs is provided, for example, by a timer value. The broadcast configuration may be received from a satellite, blimp or other moving transmitter. A dedicated configuration may also be received from the serving cell. The dedicated configuration may include a preamble, a transient configuration and an indication of a layer 2 behavior. If a WTRU detects a change in RAN function termination, the WTRU may suspend any uplink data transmissions, apply the transient configuration and transmit the preamble to a target cell. The WTRU may synchronize with the target cell and apply the layer 2 behavior.

Abstract: Methods, apparatuses, and systems for radio link monitoring (RLM) implemented by a wireless transmit/receive unit (WTRU) are provided. A representative method for RLM includes mapping, by the WTRU, one or more RLM-RS resources to at least one BLER threshold of a plurality of BLER thresholds. The representative method also includes, for each respective RLM resource that is mapped, determining, by the WTRU, a BLER of the respective RLM-RS resource, and comparing the determined BLER of the respective RLM-RS resource with the at least one mapped BLER threshold associated with the respective RLM-RS resource. The representative method further includes generating, based on one or more of the comparisons, a set of in-sync indications and/or a set of out-of-sync indications, and indicating, by the WTRU, one or more attributes associated with the set of in-sync indications and/or the set of out-of-sync indications.

Abstract: Methods to perform, maintain and report measurements on a transmission-reception point (TRP) using limited reference signal transmission are described herein. The mobility measurement reports may utilize physical channels. Methods to obtain measurements on neighbor TRPs using limited RS transmissions are also described herein. Random-Access procedures to enable the addition of a neighbor TRP or handover without requiring higher layer signaling (and possibly without an interface between source and target TRP) are also described herein. New triggers to perform RA in order to decrease handover latency are also described herein. Wireless Transmit/Receive Unit (WTRU) behavior upon receiving RAR from multiple possible TRPs are also described herein. For example, a WTRU may store RAR information and use it later in an interrupted RA procedure.

Abstract: A system and methods for beam failure recovery and management for multi-carrier communications with beamforming are disclosed herein. A wireless transmit/receive unit (WTRU) may monitor for and detect a beam failure of a beam associated with a secondary cell (Scell). The WTRU may select an Scell candidate beam. The WTRU may transmit using a selected uplink (UL) resource in a primary cell (SpCell) a medium access control (MAC) control element (CE) including an indication of Scell beam failure and identifying the selected candidate beam. The WTRU may receive an Scell beam failure indication response on the SpCell indicating an SCell index and a downlink (DL) quasi co-location (QCL) reference associated with the Scell. The WTRU may verify that the DL QCL reference matches with the candidate beam. The WTRU may perform random access on the SCell using the selected QCL reference and the selected candidate beam.

Abstract: A wireless transmit receive unit (WTRU) may operate in a dual connectivity (DC) context. While in a RRC_INACTIVE state, the WTRU may receive a paging message from a first cell, which may be associated with a master cell group (MCG). The paging message may indicate that the WTRU is to respond to the paging message on another cell. Also, or alternatively, the paging message may indicate that data for the WTRU is available on an SCG bearer. The WTRU may select a second cell (e.g., a cell other than the first cell) from a secondary cell group (SCG) list, which may include one or more secondary cells. The WTRU may initiate a random access channel procedure with the second cell based on receiving the paging message from the first cell. The WTRU may receive data from the second cell via the SCG bearer while in the RRC_INACTIVE state.

Abstract: 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.

Abstract: A wireless transmit-receive unit (WTRU) may receive an indication to switch from a point-to-point (FTP) transmission mode to a point-to-multipoint (PTM) transmission mode or determine to switch from the PTP transmission mode to the PTM transmission mode based on a reliability condition associated with the PTM mode. Based on the indication or the determination, the WTRU may switch from the PTP transmission mode to the PTM transmission mode. The WTRU may receive a first data packet. The WTRU may extend a data packet reception window by extending a boundary of the data packet reception window. The boundary may be extended based on a sequence number (SN) of the first data packet and an offset.

Abstract: A wireless transmit/receive unit (WTRU) is configured to receive a radio resource control (RRC) message. The RRC message may comprise information that indicates an association between each of a plurality of beams and power information. The WTRU is configured to receive a trigger message. The WTRU is configured to select a beam in response to the received trigger message. The WTRU is configured to send a control channel transmission using a power level. The power level may be based on the power information mapped to the selected beam.

Abstract: Methods and apparatuses for accessing a wireless network are described herein. A method according to at least one embodiment may include receiving a transmission including information associated with a plurality of random access channel (RACH) configurations. The information may indicate a plurality of RACH occasions in which a preamble transmission may be sent. One or more reference signals may be received. Methods may further include sending, using one of the plurality of RACH configurations, the preamble transmission in one of the plurality of RACH occasions along with one or more protocol data units (PDUs). The one of the plurality of RACH configurations may be selected based on a measurement of at least one of the one or more received reference signals. The method may further include sending, in response to the preamble transmission and the one or more PDUs, a random access response.

Abstract: The disclosure pertains to methods and apparatus for performing handover by a relay Wireless Transmit/Receive Unit (WTRU) from a source parent WTRU to a target parent WTRU in a wireless network comprising: obtaining uplink data determining, a channel quality for a first link between the relay WTRU and the source parent WTRU, and a channel quality for a second link between the relay WTRU and the target parent WTRU; sending, the uplink data via the first link and the second link based on any of: (1) the determined channel quality for the first link, (2) the determined channel quality for the second link, and/or (3) load conditions; and sending, to a child WTRU served by the relay WTRU via a third link, information indicating a handover of the relay WTRU from the source parent WTRU to the target parent WTRU.

Abstract: A method is described for using artificial intelligence (AI) components in association with first a transceiver node in a wireless network, where the first node is configured to send data over a wireless channel and to initiate a training procedure for an artificial intelligent component in a second node. The first node, having an encoder, transmits, to a decoder in the second node, a plurality of ordered training pairs, the transmission in response to a detection of a trigger condition based on a reconstruction loss value determined by the first node. The first node receives, from the second node, partially processed training information corresponding to the transmitted training pairs. The first node updates learnable parameters of the encoder based on the received partially processed training information to reduce the reconstruction loss value.

Abstract: A method performed by a base station may include transmitting a configuration message including at least information indicating a subset of a plurality of transmit beams to be used for transmitting a set of synchronization signals. The set of synchronization signals including a primary synchronization signal and a secondary synchronization signal may be transmitted. A random access channel (RACH) transmission may be received using a receive beam associated with one of the subset of the plurality of transmit beams used by the base station to transmit the set of synchronization signals. The transmitted set of synchronization signals transmitted may have a signal quality above a signal quality threshold. A reference signal may be transmitted along with a physical broadcast channel (PBCH) transmission. The reference signal may have a sequence derived from a beam index associated with the one of the subset of the plurality of transmit beams.