Abstract: Systems, methods, and instrumentalities are described herein for physical downlink control channel (PDCCH) coverage enhancement for reduced capability wireless transmit/receive units (WTRUs). Overbooking rules may be applied, for example, to limit the number of blind decodes, e.g., if/when PDCCH is repeated. A coverage enhancement (CE) level may be determined for a beam. Link recovery may be performed with CE levels. A PDCCH monitoring configuration may include repetitions. The number of blind decodes with repetitions may be limited. A WTRU may report an indication of a best repetition. A WTRU may be configured to perform a measurement associated with a PDCCH repetition, e.g., if/when a PDCCH subject to PDCCH repetition is successfully decoded.

Abstract: Systems, methods, and instrumentalities are described for handling positioning reference signals in a wireless communication system. The positioning reference signals may be assigned priorities that may be used to facilitate various operations of a wireless transmit/receive unit (WTRU) such as positioning related services, collision avoidance, measurement and reporting, etc. The WTRU may be configured with multiple muting patterns associated with the positioning reference signals and may switch between different muting patterns based on the priorities of the positioning reference signals and/or other downlink (DL) or uplink (UL) transmissions that may overlap or collide with the positioning reference signals.

Abstract: Methods, apparatus and systems for enabling interference avoidance, for example from self and neighboring interference are disclosed. In one representative method implemented in a Wireless Transmit/Receive Unit (WTRU) using time-frequency (TF) resources in first and second directions, the method includes comprising TF resource muting or symbol muting, by the WTRU, one or more TF resources for communication in the first direction based on information associated with a communication in the second direction or subframe shortening, by the WTRU, by one or more TF resources for communication in the first direction based on information associated with a communication in the second direction.

Abstract: A wireless transmit/receive unit (WTRU) may measure one or more of a first plurality of beam reference signals. Further, the WTRU may select a first beam reference signal from among the measured one or more of the first plurality of beam reference signals. Also, WTRU may determine a set of physical random access channel (PRACH) resources for the selected first beam reference signal. Moreover, the WTRU may measure one or more of a second plurality of beam reference signals. Further, the WTRU may select a second beam reference signal from among the measured one or more of the second plurality of beam reference signals. The WTRU may transmit an indication of the selected second beam reference signal in a physical uplink shared channel (PUSCH) transmission, and may transmit a PRACH signal using at least one PRACH resource of the determined set of PRACH resources.

Abstract: Systems, methods, and instrumentalities are disclosed for phase noise reference signal (PNRS) transmission, comprising receiving, at a wireless transmit receive unit (WTRU), scheduling information for a Physical Uplink Shared Channel (PUSCH) transmission, wherein the scheduling information includes an indication of a set of physical resource blocks (PRBs) and a modulation coding scheme (MCS) level, determining a density for the PNRS transmission based on at least one of: the MCS level, a frequency band for the PUSCH transmission, or a subcarrier spacing of the PUSCH transmission, and transmitting the PUSCH in the scheduled set of PRBs using the determined density of PNRS.

Abstract: A method performed by a wireless transmit/receive unit (WTRU) may include receiving configuration information for reporting a power headroom (PH) associated with each of a plurality of cells, wherein a first cell uses first time intervals each having a first length and a second cell uses second time intervals each having a second length. The method may include transmitting a first uplink transmission using a first carrier frequency associated with the first cell and transmitting, in one of the second time intervals that is fully overlapped by the one of the first time intervals, based on the received configuration information, a report including information indicating a first PH corresponding to the one of the first time intervals and a second PH corresponding to the earliest one in time of the second time intervals that is fully overlapped by the one of the first time intervals.

Abstract: A wireless transmit/receive unit (WTRU) may transmit a preamble using a physical random access channel (PRACH) and determine a location of a random access response (RAR) based on a parameter of the PRACH. The location may include a subframe and/or a frequency resource on which the RAR is transmitted. The RAR may be received at the location. A device may receive a preamble using a PRACH associated with a coverage enhancement (CE) level and/or a CE mode of a WTRU. The device may determine a location of an RAR based on a parameter of the PRACH. The location may include a subframe and/or a frequency resource on which the RAR is to be transmitted. The device may determine a number of repetitions of the RAR to transmit based on the CE level or CE mode. The RAR may be transmitted at the location with the determined number of repetitions.

Abstract: Methods, systems and apparatus are provided for hybrid automatic repeat request (HARQ) processes. A base station may transmit first uplink (UL)-downlink (DL) configuration information indicating a first UL-DL configuration, and may transmit second UL-DL configuration information indicating a second UL-DL configuration. The base station may transmit a physical downlink shared channel (PDSCH) transmission in a DL direction of one or more first symbols in a first subframe. The DL direction of the one or more first symbols may be based on the first UL-DL configuration and the second UL-DL configuration. The base station may receive first acknowledgement (ACK)/negative ACK (NACK) information in a UL direction of one or more second symbols in the first subframe. The first ACK/NACK information may be based on the PDSCH transmission. The UL direction of the one or more second symbols may be based on the first UL-DL configuration and the second UL-DL configuration.

Abstract: A WTRU may receive downlink control information (DCI) indicating a start of a frame. The DCI may be received on a control channel, such as the Physical Downlink Control Channel (PDCCH) from an eNB, base station, AP, or other infrastructure equipment operating in a wireless communications system. The WTRU may decode the DCI and may determine a transmit time interval (TTI) duration, which may be expressed in terms of an integer number of basic time intervals (BTIs). The WTRU may determine a downlink (DL) transmission portion and assignment and an uplink (UL) transmission portion and UL grant based on the received DCI. Additionally, the WTRU may determine the start of the UL portion based on an offset (toffset). The WTRU may receive data in a DL portion of the frame and may transmit in an UL portion of the frame based on the determined UL grant and TTI duration.

Abstract: Methods, apparatus, systems, architectures and interfaces for reference signal (RS) configuration, generation, and/or transmission in a transmitter/receiver. The method includes receiving information indicating any of at least first and second modes of operation for transmitting a discrete Fourier transform (DFT)-spread-orthogonal frequency division multiplexing (DFT-s-OFDM) symbol including a reference signal (RS), and transmitting the DFT-s-OFDM symbol including: (1) the RS and data tones, on condition that the information indicates the first mode; or (2) the RS and null tones, on condition that the information indicates the second mode, wherein the DFT-s-OFDM symbol is divided into a number of segments, each including a chunk of RS tones, and wherein any of a size or a location of the chunk is determined according to any of the first or second modes.

Abstract: Systems and methods are disclosed for determining a first downlink control indicator (DCI) and a second DCI, determining a set of active aperiodic channel state information reference signals (A-CSI-RSs) based on the first DCI, and determining a subset of the set of active A-CSI-RSs based on the second DCI. A WTRU may perform resource element (RE) muting based on a set of active A-CSI-RSs. A WTRU may perform channel state information (CSI) measurement based on a subset of a set of active A-CSI-RSs.

Abstract: Systems, methods and instrumentalities are disclosed for WTRU-initiated beam recovery including beam switching and/or beam sweeping. A WTRU may be configured to detect a beam failure condition, identify a candidate beam for resolving the beam failure condition, and send a beam failure recovery request to a network entity. The WTRU may include the candidate beam in the beam failure recovery request and may receive a response from the network entity regarding the request and/or a solution for the beam failure condition. WTRU-initiated beam recovery may be used to resolve radio link failures and improve system performance by avoiding the necessity to perform an acquisition procedure. Additionally, beam sweeping may be performed at a sub-time unit level to provide a fast sweeping mechanism.

Abstract: A wireless transmit/receive unit (WTRU) may monitor control resource sets (CORESETs) to receive a physical downlink control channel (PDCCH) having downlink control information (DCI) that includes a scheduling offset and an indicated beam for a scheduled physical downlink shared channel (PDSCH) reception. When the scheduling offset of the scheduled PDSCH is less than a threshold, a default beam of a transmission configuration indication (TCI) state may be utilized to receive the scheduled PDSCH. When the scheduling offset of the scheduled PDSCH is more than a threshold, the indicated beam is utilized to receive the scheduled PDSCH on a condition that a measured quality is above a measurement threshold or the default beam may be utilized when the measured quality is below the measurement threshold.

Abstract: Methods and systems for sending and receiving an enhanced downlink control channel are disclosed. The method may include receiving control channel information via an enhanced control channel. The method may also include using the control channel information to receive a shared channel. The method may include detecting the presence of the enhanced control channel in a given subframe. The enhanced control channel may be transmitted over multiple antenna ports. For example, code divisional multiplexing and de-multiplexing and the use of common and UE-specific reference signals may be utilized. New control channel elements may be defined, and enhanced control channel state information (CSI) feedback may be utilized. The presence or absence of legacy control channels may affect the demodulation and or decoding methods. The method may be implemented at a WTRU.

Abstract: Method and WTRU enabled for service continuity using WTRU-to-WTRU relays. A relay path may be modeled as an SLRB, RLC leg of an SLRB, and/or a MAC logical channel. The WTRU adds a path for a destination based on configured/usable relays. The WTRU may associate an end-to-end L2 destination ID with one or more path L2 destination IDs or path IDs. Upper layers select one or more paths for transmission of a packet/bearer. The WTRU may send a relay announcement message containing path connectivity information. A WTRU may select a path for transmission based on properties associated with a sidelink. The WTRU may activate/deactivate an SL bearer, unicast link, L2 destination, and/or RLC Leg. The WTRU changes a bearer associated with an SLRB from an established RLC entity to another established RLC entity.

Abstract: The disclosed method and an apparatus are directed to determine an uplink transmission power in in New Radio (NR) systems by a wireless transmit/receive unit (WTRU) for transmitting at least one physical uplink shared channel (PUSCH), using multiple beams toward multiple Tx/Rx points (TRPs). The method includes determining common parameters like a target receive power, a modulation and coding scheme (MCS) specific offset, and a transmit power control (TPC) command parameters common to the multiple beams. The method also includes determining beam-specific parameters like path loss for each beam, a configurable fractional power compensation factor for each beam, and a configurable maximum transmit power level of the each beam, wherein the fractional power compensation factor and the configurable maximum transmit power level for the each beam are determined dynamically or semi-statically based on at least deployment, WTRU mobility, or interference level.

Abstract: A method for transmitting a reference signal in a multi-antenna system is provided. The method includes: selecting at least one orthogonal frequency division multiplexing (OFDM) symbol in a subframe containing a plurality of OFDM symbols; allocating a channel quality indication reference signal (CQI RS) capable of measuring a channel state for each of a plurality of antennas to the selected at least one OFDM symbol; and transmitting the CQI RS, wherein the CQI RS is allocated to an OFDM symbol which does not overlap with an OFDM symbol to which a common reference signal to be transmitted to all user equipments in a cell or a dedicated reference signal to be transmitted to a specific user equipment in the cell is allocated.

Abstract: A wireless transmit/receive unit (WTRU) may be configured to receive configuration information associated with a first transmission configuration indicator (TCI) state group and a second TCI state group. The WTRU may be configured to report first respective measured downlink received power values and first respective determined power reduction values. The WTRU may be configured to report second respective measured downlink received power values and second respective determined power reduction values. The WTRU may be configured to receive an indication of the first TCI state group via a downlink transmission. The WTRU may be configured to determine a first TCI state from the first TCI state group based on downlink received power information and power reduction information. The WTRU may be configured to send an uplink transmission based on the first determined TCI state.

Abstract: Methods and systems for sending and receiving an enhanced downlink control channel are disclosed. The method may include receiving control channel information via an enhanced control channel. The method may also include using the control channel information to receive a shared channel. The method may include detecting the presence of the enhanced control channel in a given subframe. The enhanced control channel may be transmitted over multiple antenna ports. For example, code divisional multiplexing and de-multiplexing and the use of common and UE-specific reference signals may be utilized. New control channel elements may be defined, and enhanced control channel state information (CSI) feedback may be utilized. The presence or absence of legacy control channels may affect the demodulation and or decoding methods. The method may be implemented at a WTRU.

Abstract: Reference signals configured for use with extension carriers and/or carrier segments are described. Reference signals for extension carriers and/or carrier segments may include demodulation reference signals (e.g., user equipment-specific reference signals), cell-specific reference signals, and channel-state information reference signals. Methods, systems and apparatuses for configuring extension carriers and/or carrier segments with one or more of the reference signals (e.g., positioning one or more reference signal symbols in extension carriers and/or carrier segments) are described.