Abstract: Systems, methods, and instrumentalities are described herein that may be used to determine a destination for sidelink transmission based on the priority of the transmission and/or other parameters associated with the transmission. In examples, a destination may be selected if one or more logical channels associated with the destination have a bucket size parameter exceeding a certain threshold and the one or more logical channels have a highest priority. Various other techniques are also described herein that relate to the configuration and/or report of QoS information, selection of sidelink resources, use of a minimum communication range, etc.

Abstract: Methods and apparatuses are described herein for monitoring radio links between wireless transmit/receive units (WTRUs) and determining of radio link failure, and may be used, among others, for New Radio (NR) vehicular communication (V2X); a mode whereby WTRUs can communicate with each other directly. A radio link between a WTRU and another WTRU may be monitored independently per ongoing unicast and/or multicast link, and radio link failure (RLF) may be determined as a function of the monitoring.

Abstract: Systems, methods, and devices for enabling simultaneous transmission of different types of transmission protocols. A device such as a wireless transmit receive unit (WTRU) may receive configuration information and receive a data packet from an upper layer of a protocol stack operating on the WTRU. The WTRU may then determine a transmission type for the data packet at a first time based on the configuration information and a condition. The WTRU may then transmit the data packet using the determined transmission type. The configuration information may include decision criteria associated with determining the transmission type and a set of logical channels that are associated with data properties. The transmission type may be one of a network scheduled mode, WTRU autonomously scheduled mode, LTE, NR, unicast, groupcast, or broadcast.

Abstract: A wireless transmit/receive unit (WTRU) operating in an autonomous-scheduled mode may select a first resource from a resource pool. The WTRU may determine that the first resource is reserved for at least one sidelink transmission scheduled via a network-scheduled mode. The WTRU may evaluate the availability of resources in the resource pool based on determining that the first resource is reserved for the sidelink transmission. The WTRU may determine that a resource is available based on a measurement comparison to one or more thresholds. For example, there may be a first threshold for resources reserved by WTRUs operating using the network-scheduled mode and a second threshold for resources reserved by WTRUs operating using the autonomous-scheduled mode. The first threshold may be determined based on the second threshold and an offset value. The WTRU may reselect to a second resource in the resource pool based on the evaluated resource availability.

Abstract: Systems, methods, and devices for unicast and/or multicast link establishment and maintenance. A wireless transmit receive unit (WTRU) may send a link establishment request broadcast message, wherein in the link may be for multicast, unicast, or groupcast. The WTRU may receive a link establishment response broadcast message and a connectivity report. The WTRU may then send a link establishment confirmation broadcast message once a multicast or unicast link has been established, at which point the WTRU may send and receive a multicast message. The link establishment request message may be sent based on one or more triggers: receiving a QoS flow, needing a new sidelink radio bearer, determining that a new QoS flow or radio bearer requires network controlled admission control, and/or receive a unicast and/or multicast establishment request. The WTRU may transmit a unicast and/or multicast usability signal (UMUS). The WTRU may preempt the established multicast or unicast link.

Abstract: A WTRU apparatus and method for operation thereby are provided. The method may comprise receiving, from a network, a mapping rule which indicates HARQ feedback characteristics to employ for a QoS level and a channel load. The WTRU may determine a QoS level of data buffered for transmission and may further determine a channel load of a channel. Based on the QoS level and channel load, HARQ feedback characteristics may be determined. The WTRU may then transmit an SCI to another WTRU which indicates the HARQ feedback characteristics. In an embodiment, the mapping rule may indicate that a HARQ feedback format is to be used for HARQ feedback of the data. The data may be transmitted and HARQ feedback of the data may be received in accordance with the HARQ feedback format. Groupcast data may be transmitted to a plurality of WTRUs and feedback my be received.

Abstract: Methods and apparatuses are described herein for sidelink communication in a wireless transmit/receive unit (WTRU). For example, a first WTRU configured with first and second resource pools may perform at least one congestion measurement of the second resource pool. The first resource pool may be configured for use by the first WTRU for transmission of the first data. The second resource pool may be configured for use by a second WTRU for transmission of the second data associated with a higher priority than the first data. If the at least one congestion measurement of the second resource pool is below a predetermined threshold, the first WTRU may transmit the first data using the first resource pool. If the at least one congestion measurement of the second resource pool is above a predetermined threshold, the first US may not transmit the first data using the first resource pool.

Abstract: Methods, devices, and systems for congestion control in a wireless communications system. Some embodiments include receiving a plurality of zone configurations, receiving, for each of the plurality of zone configurations, a channel busy ratio (CBR) threshold and a mapping of zone identities (IDs) to resource pools; and measuring a CBR of a resource pool with which the WTRU is currently configured.

Abstract: A wireless transmit/receive unit (WTRU) operating in an autonomous-scheduled mode may select a first resource from a resource pool. The WTRU may determine that the first resource is reserved for at least one sidelink transmission scheduled via a network-scheduled mode. The WTRU may evaluate the availability of resources in the resource pool based on determining that the first resource is reserved for the sidelink transmission. The WTRU may determine that a resource is available based on a measurement comparison to one or more thresholds. For example, there may be a first threshold for resources reserved by WTRUs operating using the network-scheduled mode and a second threshold for resources reserved by WTRUs operating using the autonomous-scheduled mode. The first threshold may be determined based on the second threshold and an offset value. The WTRU may reselect to a second resource in the resource pool based on the evaluated resource availability.

Abstract: A method and apparatus for selecting a resource for transmission may be performed by a WTRU. The method may comprise determining a priority of a data packet and determining a CBR of a resource pool. The WTRU may set a backoff counter to an initial backoff value, in accordance with at least one of the priority of the packet or the CBR. A CCA may be performed in a plurality of resource slots to determine whether the resource slots are available. The backoff counter may be decreased by the number of available resources in each slot. When the backoff counter reaches a threshold value, which may be set at 0, the resource for transmission may be randomly selected. The WTRU may then transmit data to another WTRU on the randomly selected resource.

Abstract: A 5G UE achieves flexible SL time resource granularity by determining which UL/Flexible symbols/slots belong to a symbol-based SL resource pool and a slot-based SL resource pool based on SFI in RRC/GC-PDCCH. The UE then determines which resources are available in each pool based on sensing and selects a resource pool to use so that QoS/latency requirements are met.

Abstract: Methods, systems, and apparatuses for sidelink communication are disclosed. A WTRU may receive a first SCI element from a second WTRU within a group. The WTRU may receive a first RCI element within a first set of resources scheduled by the first SCI. The first RCI may include information about which WTRU in the group is scheduled to use a second set of resources. The WTRU may determine, based on the first RCI, that one or more subresources within the second set of resources are available. The WTRU may transmit data in the one or more subresources. The first SCI and the first RCI may be received in a first reservation period and the one or more subresources may be in a second reservation period.

Abstract: A wireless transmit/receive unit (WTRU) operating in an autonomous-scheduled mode may select a first resource from a resource pool. The WTRU may determine that the first resource is reserved for at least one sidelink transmission scheduled via a network-scheduled mode. The WTRU may evaluate the availability of resources in the resource pool based on determining that the first resource is reserved for the sidelink transmission. The WTRU may determine that a resource is available based on a measurement comparison to one or more thresholds. For example, there may be a first threshold for resources reserved by WTRUs operating using the network-scheduled mode and a second threshold for resources reserved by WTRUs operating using the autonomous-scheduled mode. The first threshold may be determined based on the second threshold and an offset value. The WTRU may reselect to a second resource in the resource pool based on the evaluated resource availability.