Abstract: Systems, devices and methods for a backscatter measurement based multiple RACH preamble transmissions are disclosed. A WTRU may receive a JCS-RS configuration comprising a minimum RACH preamble retransmission interval. The JCS-RS configuration may comprise a JCS backscatter power fraction (?) of the WTRU transmit power (PTx). The WTRU may transmit a RACH preamble in a RACH occasion corresponding to a preferred SS/PBCH Index using an initial WTRU transmit beam, having an associated first RA-RNTI value. The backscatter power (PBS) may be measured using the WTRU receive beam corresponding to the WTRU transmit beam used for the RACH preamble transmission. On a condition that PBS>?PTx, the WTRU may retransmit the RACH preamble after a retransmission interval, on resources associated with a second RA-RNTI value. The WTRU may be configured for monitoring the PDCCH common search space with the first RA-RNTI and the second RA-RNTI, for respective RAR window intervals.

Abstract: Systems, methods and instrumentalities for a distributed detect and avoid (DM) framework for unmanned vehicles, such as unmanned aerial vehicles (UAVs). The systems, methods and instrumentalities may include a wireless transmit/receive unit (WTRU) associated with a vehicle. The WTRU may include a memory and a processor. The processor may be configured to store a trajectory of the vehicle and to send a message indicative of a conflict between the trajectory of the vehicle and a trajectory of another vehicle. The processor may be configured to receive a message from the other vehicle that is indicative of one or more conflicts and to determine a list that includes the vehicle(s) associated with the one or more conflicts. The processor may be configured to determine a resolution that addresses the conflict(s) associated with the list.

Abstract: A wireless transmit/receive unit (WTRU) receives first timing advances and first power control commands from a first eNodeB and second timing advances and second power control commands from a second eNodeB and transmits, to the first eNodeB, a first physical uplink control channel using a first uplink component carrier. The first physical uplink control channel has a first timing adjusted by the first timing advances but not by the second timing advances and a first power level adjusted by the first power control commands but not by the second power control commands. The WTRU transmits a second physical uplink control channel using a second uplink component carrier. The second physical uplink control channel has a second timing adjusted by the second timing advances but not by the first timing advances and a second power level adjusted by the second power control commands but not by the first power control commands.

Abstract: A method and apparatus are described for supporting a two-stage device-to-device (D2D) discovery using a D2D interworking function (IWF). A D2D IWF component may be configured to perform mapping between an application running on an application server and a third generation partnership project (3GPP) network, and provide a set of application programming interfaces (APIs) to allow discovery to be provided as a service to D2D applications. An application identifier may be mapped to a 3GPP identifier. Further, a method and apparatus are described for performing client-server discovery. A first wireless transmit/receive unit (WTRU) may be configured for a listen-only operation, and a second WTRU may be configured to transmit beacons. The first and second WTRUs may perform a radio access network (RAN) discovery procedure at an access stratum (AS) layer. A method and apparatus for performing charging for D2D service using a D2D IWF are also described.

Abstract: Methods and apparatuses for receive (Rx) beam selection are described herein. In one example, a method includes receiving configuration information indicating resources for receiving a first set of reference signals from one or more transmit/receive points (TRPs) using a first set of receive (Rx) beams, one or more first resource sets for a second set of reference signals, and one or more second resource sets for transmitting a measurement report. The method includes transmitting a measurement report using one of the one or more second resource sets. The measurement report is based on measurements associated with one or more reference signals of the second set of reference signals. The method includes determining a second set of Rx beams. The method includes receiving the first set of reference signals from the one or more TRPs using the second set of Rx beams.

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 and apparatuses are described herein for paring an unmanned aerial vehicle (UAV) with a UAV-controller (UAV-C). For example, a UAV having a UAV wireless transmit/receive unit (UAV WTRU) may transmit, to an access and mobility management function (AMF), a non-access stratum (NAS) request message that includes a paring request indication and a UAV-controller (UAV-C) identification (UAV-C ID). The UAV-C ID may be carried in a paring request to an unmanned aerial system (UAS) service supplier (USS)/UAS traffic management (UTM) for paring authorization of the UAV with a UAV-C associated with the UAV-C ID. The UAV may receive, from the AMF, a NAS response message that includes an unmanned aerial system (UAS) identification (UAS ID) indicating that the UAV is paired with the UAV-C, wherein the UAS ID is assigned by the USS/UTM.

Abstract: Methods and apparatuses for receive (Rx) beam selection are described herein. A wireless transmit/receive unit (WTRU) may be configured to receive, from a base station (BS), configuration information for joint communication and sensing (JCS) reference signals. The configuration information may include resources for reference signal transmission and resources for measurement reporting. The WTRU may be further configured to receive, from the BS, an indication to activate a subset of the resources for JCS reference signal transmission. The WTRU may be further configured to transmit, a plurality of JCS reference signals using the activated subset of resources for reference signal transmission. The WTRU may be further configured to measure, via a plurality of Rx beams, a backscatter power associated with each of the transmitted plurality of JCS reference signals. The WTRU may be further configured to calculate beam blockage statistics based on the measured backscatter power.

Abstract: Methods, systems, and devices for addressing timing advance (TA) in non-terrestrial network communication is disclosed herein. A wireless transmit and receive unit (WTRU) may receive system information from a base station attached to an airborne or spaceborne vehicle that indicates a physical random access channel (PRACH) resource. The WTRU may determine a timing offset based on a plurality of information, such as the location information and the system information. The WTRU may transmit a preamble using the timing offset via the PRACH resource. The base station may receive the preamble and send a random access response (RAR) that includes, for example, a TA command. The WTRU may receive the RAR including the TA command and combine the timing offset with the TA command to determine an actual TA, after which the WTRU may use the actual TA for uplink transmissions.

Abstract: A method for use in a Wireless Transmit/Receive Unit (WTRU). The method comprises: receiving, using an active receiver, system information comprising a first system information set, wherein the first system information set is currently valid for the WTRU; storing the system information; deactivating the active receiver and activating a passive receiver; determining whether a difference between a first parameter in the BSSI and a first parameter in the first system information set is greater than a threshold value, wherein on a condition that the difference is greater than the threshold value, reactivating the active receiver to receive a second system information set as a currently valid system information set for the WTRU.

Abstract: Methods and apparatuses for receive (Rx) beam selection are described herein. A wireless transmit/receive unit (WTRU) may be configured to receive, from a base station (BS), configuration information for joint communication and sensing (JCS) reference signals. The configuration information may include resources for reference signal transmission and resources for measurement reporting. The WTRU may be further configured to receive, from the BS, an indication to activate a subset of the resources for JCS reference signal transmission. The WTRU may be further configured to transmit, a plurality of JCS reference signals using the activated subset of resources for reference signal transmission. The WTRU may be further configured to measure, via a plurality of Rx beams, a backscatter power associated with each of the transmitted plurality of JCS reference signals. The WTRU may be further configured to calculate beam blockage statistics based on the measured backscatter power.

Abstract: Approaches for idle mode operations for wireless transmit/receive units (WTRUs) with zero-energy (ZE) receivers are disclosed herein. A WTRU operating in idle mode, may receive using the main transceiver over a Uu interface, an energy harvesting (EH) configuration for use over a ZE air interface. The main transceiver may be turned off, and the ZE receiver as part of a ZE idle mode operation, may detect, over the ZE air interface, and harvest energy from ZE reference signals. The WTRU may calculate an amount of energy harvested from the ZE reference signals over a first time period. The WTRU may calculate a ZE idle mode operation energy consumption over the first time period. On a condition that the ZE idle mode operation energy consumption is greater than the harvested energy, the main transceiver may be turned on and the WTRU may enter a Uu interface idle mode operation.

Abstract: A wireless transmit/receive unit (WTRU) may receive a downlink communication from a network over a first interface transmitted to one or more WTRUs in a group of WTRUs. The WTRU may determine an access class of the WTRU based on a packet loss percentage of the downlink communication. The access class may be associated with a contention window for accessing a second interface. The WTRU may transmit packet loss information to the one or more WTRUs over the second interface in the contention window. The WTRU may receive packet loss feedback from the one or more WTRUs over the second interface. The WTRU may determine that the access class of the WTRU is a highest class of the one or more WTRUs. The WTRU may transmit a single groupcast negative acknowledgement (gNACK) to the network on behalf of the one or more WTRUs over the first interface.

Abstract: Methods, systems, and devices for addressing timing advance (TA) in non-terrestrial network communication is disclosed herein. A wireless transmit and receive unit (WTRU) may receive system information from a base station attached to an airborne or spaceborne vehicle that indicates a physical random access channel (PRACH) resource. The WTRU may determine a timing offset based on a plurality of information, such as the location information and the system information. The WTRU may transmit a preamble using the timing offset via the PRACH resource. The base station may receive the preamble and send a random access response (RAR) that includes, for example, a TA command. The WTRU may receive the RAR including the TA command and combine the timing offset with the TA command to determine an actual TA, after which the WTRU may use the actual TA for uplink transmissions.

Abstract: Methods and apparatuses are described herein for paring an unmanned aerial vehicle (UAV) with a UAV-controller (UAV-C). For example, a UAV having a UAV wireless transmit/receive unit (UAV WTRU) may transmit, to an access and mobility management function (AMF), a non-access stratum (NAS) request message that includes a paring request indication and a UAV-controller (UAV-C) identification (UAV-C ID). The UAV-C ID may be carried in a paring request to an unmanned aerial system (UAS) service supplier (USS)/UAS traffic management (UTM) for paring authorization of the UAV with a UAV-C associated with the UAV-C ID. The UAV may receive, from the AMF, a NAS response message that includes an unmanned aerial system (UAS) identification (UAS ID) indicating that the UAV is paired with the UAV-C, wherein the UAS ID is assigned by the USS/UTM.

Abstract: Methods and apparatuses are provided herein. A method may include receiving, from a first network node, configuration information to establish a link to a second network node. The first network node may use a first radio access technology (RAT) and the second network node may use a second RAT. The configuration information may include timing information associated with a first one of a plurality of beams of the second network node. The method may include measuring the first one of the plurality of beams of the second network node based on the timing information. The method may include selecting a beam of the plurality of beams of the second network node based on the measurement. The method may include sending a transmission to at least the first network node. The transmission may be an indication the WTRU is configured to establish the link to the second network node.

Abstract: A method and apparatus are disclosed for communication in a Millimeter Wave Hotspot (mmH) backhaul system which uses mesh nodes. A mmH mesh node may receive a control signal which includes a total number of available control slots. The mesh node may determine the number of iterations of a resource scheduling mechanism that can be made during the time period of all available control slots, based on the number of neighbor nodes for the mesh node. Further, the mesh node may receive control slot information, including information about traffic queues and priorities. The mesh node may then perform resource scheduling using the resource scheduling mechanism based on the currently received control slot information and control slot information received in previous iterations of resource scheduling. The mesh node may also adjust a preamble based on a time between a last packet transmission and a current packet transmission to a neighboring node.

Abstract: A wireless transmit/receive unit (WTRU) (e.g., a millimeter WTRU (mWTRU)) may receive a first control channel using a first antenna pattern. The WTRU may receive a second control channel using a second antenna pattern. The WTRU may demodulate and decode the first control channel. The WTRU may demodulate and decode the second control channel. The WTRU may determine, using at least one of: the decoded first control channel or the second control channel, beam scheduling information associated with the WTRU and whether the WTRU is scheduled for an mmW segment. The WTRU may form a receive beam using the determined beam scheduling information. The WTRU receive the second control channel using the receive beam. The WTRU determine, by demodulating and decoding the second control channel, dynamic per-TTI scheduling information related to a data channel associated with the second control channel.

Abstract: Methods, systems, and devices for addressing timing advance (TA) in non-terrestrial network communication is disclosed herein. A wireless transmit and receive unit (WTRU) may receive system information from a base station attached to an airborne or spaceborne vehicle that indicates a physical random access channel (PRACH) resource. The WTRU may determine a timing offset based on a plurality of information, such as the location information and the system information. The WTRU may transmit a preamble using the timing offset via the PRACH resource. The base station may receive the preamble and send a random access response (RAR) that includes, for example, a TA command. The WTRU may receive the RAR including the TA command and combine the timing offset with the TA command to determine an actual TA, after which the WTRU may use the actual TA for uplink transmissions.

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.