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.

Abstract: A base station may sense, on a cell using unlicensed spectrum, that the unlicensed spectrum is available for transmission. The base station may transmit, after sensing that the unlicensed spectrum is available, consecutive subframes. Each subframe may include a physical downlink control channel and a physical downlink shared channel.

Abstract: Methods and apparatus are described for providing compatible mapping for backhaul control channels, frequency first mapping of control channel elements (CCEs) to avoid relay-physical control format indicator channel (R-PCFICH) and a tree based relay resource allocation to minimize the resource allocation map bits. Methods and apparatus (e.g., relay node (RN)/evolved Node-B (eNB)) for mapping of the Un downlink (DL) control signals, Un DL positive acknowledgement (ACK)/negative acknowledgement (NACK), and/or relay-physical downlink control channel (R-PDCCH) (or similar) in the eNB to RN (Un interface) DL direction are described. This includes time/frequency mapping of abovementioned control signals into resource blocks (RBs) of multimedia broadcast multicast services (MBMS) single frequency network (MBSFN)-reserved sub-frames in the RN cell and encoding procedures for these.

Abstract: A wireless transmit/receive unit (WTRU) is configured to receive a WTRU-specific configuration of WTRU-specific sounding reference signal (SRS) subframes for performing SRS transmissions. The WTRU is configured to receive a trigger in a subframe to transmit a first SRS. The WTRU is configured to select a first subframe. The WTRU is configured to determine that a maximum power would be exceeded in a symbol in the selected first subframe. The WTRU is configured to, on a condition that transmission of at least one other SRS would at least partially overlap in the symbol in the selected first subframe, scale transmission powers of the first SRS and the at least one other SRS equally to comply with the maximum power. The WTRU is configured to transmit, in accordance with the scaled transmission powers, the first SRS in the selected subframe and the at least one other SRS.

Abstract: Methods and devices may be provided for aggregating component carriers in the licensed spectrum with at least one component carriers in the licensed exempt spectrum. Control information may be processed in a wireless transmit/receive unit (WTRU) while receiving and sending information on a primary component carrier (PCC) and a supplementary component carrier (SuppCC). A PCC subframe with a control portion and a data portion may be received. Resource assignment information associated with a downlink shared channel on the PCC may be embedded in the control portion of the subframe. Based on the resource assignment information on the PCC, resource assignment information associated with a downlink shared channel on the SuppCC may be identified in the data portion of the PCC subframe. A SuppCC subframe of the shared channel on the SuppCC may be processed as per the identified resource assignment information associated with the downlink shared channel on the SuppCC.

Abstract: Methods and apparatus are described. A method, implemented in a wireless transmit/receive unit (WTRU) includes monitoring a first control channel search space (SS) associated with a first normal beam set comprising a first beam set. The WTRU initiates extended monitoring and monitors, subsequent to a trigger based on a measurement by the WTRU, a control channel SS associated with an extended beam set comprising the first beam set and one or more additional beam sets. The WTRU determines a second beam set from the extended beam set. The determination is based on a received control channel beam switch command or based on a control channel SS in which a beam switch command is received. The WTRU monitors a second control channel SS associated with a second normal beam set comprising the determined second beam set.

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, 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: Methods and apparatus for initial cell search and selection using beamforming are described. An apparatus is configured with multiple receive beams and includes an antenna and a processor. The processor is operatively coupled to the antenna and sweeps a respective one of the multiple receive beams during each of multiple synchronization sub-frames, using a pre-defined sweep time and dwell period, to detect a synchronization signal. The processor also obtains symbol timing information and a synchronization signal index from the detected synchronization signal. The obtained synchronization signal index corresponds to a synchronization signal index of the set. The process decodes a first broadcast channel using the obtained symbol timing information, the obtained synchronization signal index and a predefined or blind-coded symbol distance between the detected synchronization signal and the first broadcast channel.

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 receive a first signal including a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). The PSS and SSS may be received in a resource block of a cell and the resource block may have a first numerology. Further, the first numerology may have a first subcarrier spacing, while other resources of the cell at a same time as the resource block may have a second numerology with a different subcarrier spacing than the first numerology. In addition, the WTRU may determine synchronization based on the PSS and SSS. Also, the WTRU may receive a second signal in the cell, and the second signal may have the second numerology. Moreover, the WTRU may transmit user data. In a further example, the WTRU may search a frequency raster for the PSS and the SSS.

Abstract: A wireless transmit/receive unit (WTRU) is configured to receive an identifier of a beam. The WTRU is configured to measure a downlink quality associated with at least one beam. The WTRU is configured to determine whether the measured downlink quality is below a threshold value. The WTRU is configured to receive at least one control channel transmission using the beam of the identifier in response to a determination that the measured downlink quality is below the threshold value, wherein the beam used to receive the at least one control channel transmission is a same beam used to receive an associated data channel transmission.

Abstract: A wireless transmit/receive unit (WTRU) may determine physical uplink control channel (PUCCH) resources for a PUCCH based on a number of hybrid automatic repeat request (HARQ) bits and based on a parameter. The WTRU may determine a format of the PUCCH based on symbols for uplink control information (UCI) and based on the number of HARQ bits.

Abstract: Systems, methods, and instrumentalities are disclosed for non-orthogonal multiple access (NOMA), frequency hopping, and power control. NOMA may be applied to asynchronous and/or grant-free transmissions. Transmissions from multiple WTRUs may be performed using the same resources, and may comprise information for correctly identifying and decoding the transmissions. The transmissions may comprise a built-in deterministic sequence to support timing acquisition at a receiver. The transmissions may be distinguished based on respective transmit power used for the transmissions. Such transmit power may be dynamically controlled by applying a randomly selected power offset. The power control may be performed autonomously by a WTRU.

Abstract: A wireless transmit/receive unit (WTRU) configured to perform wireless communications in higher frequency bands (e.g., above 6 GHz) using a fallback scheme is provided. The WTRU includes a receiver configured to receive, in a time transmission interval (TTI), at least one control signal and a first data signal using a first beam associated with a first beam identifier (ID) and a second data signal, subsequent to the first data signal, using a second beam associated with a second beam ID different from the first beam ID, such that one of the at least one control signal indicates the second beam ID; and a processor configured to switch a receive beam of the receiver from the first beam to the second beam based on the second beam ID to receive the second data signal.

Abstract: Systems, devices, and methods for operating in an unlicensed band are disclosed herein. In one example, a device may receive configuration information that includes a maximum channel occupancy time (MCOT) and a plurality of parameters including a plurality of transmission opportunity windows (TOWs). Based on the configuration information, the device may split a transmission into a plurality of bursts that may be grouped into sets of bursts based on how many bursts fit within a TOW. The number of bursts in a set of bursts may be less than or equal to the MCOT. The device may perform a clear channel assessment (CCA) to determine if the channel is busy and to determine a start time within the TOW for the bursts. The device may then transmit the set of bursts for that TOW, where each burst may have a burst indicator (BI).

Abstract: A wireless transmit/receive unit (WTRU) may receive configuration information indicating a set of physical channel frequency resources. The WTRU may receive downlink control information (DCI), and the DCI may include an indication of an allocation of at least a subset of the set of physical channel frequency resources. Further, the WTRU may determine a time period and one or more physical channel frequency resources from the subset of the set of physical channel frequency resources. The WTRU may transmit control information in a physical shared channel transmission using the determined one or more physical shared channel frequency resources during the determined time period. Also, the control information may include a WTRU-identifier (ID) associated with the WTRU. In an example, the control information may include a new data indicator (NDI) or a retransmission of previously transmitted control information. In a further example, the physical shared channel transmission may further include data.

Abstract: A method and apparatus for supporting communication buffer status reports (BSRs) are disclosed. A wireless device may generate a first buffer status report (BSR) associated with first data for transmission to at least one wireless transmit/receive unit (WTRU). Also, the wireless device may generate a second BSR associated with second data for transmission to a base station. Further, the wireless device may transmit the first BSR and the second BSR in a media access control (MAC) protocol data unit (PDU) to the base station. Additionally, the wireless device may transmit the first data to the at least one WTRU. Moreover, the wireless device may transmit the second data to the base station. In a further example, the wireless device may generate the first BSR and generate the second BSR are based on a priority associated with the first BSR and a priority associated with the second BSR.

Abstract: Methods, apparatuses and systems are provided for grant-less (GL) uplink transmissions. A wireless transmit/receive unit (WTRU) may receive a configuration of a set of GL Physical Uplink Shared Channel (GL-PUSCH) frequency resources. The WTRU may monitor for a downlink control information (DCI) message, wherein the DCI message includes an indication of a presence of at least a subset of the set of GL-PUSCH frequency resources. If the WTRU successfully receives the DCI message, the WTRU may select one or more GL-PUSCH frequency resources from the subset of the set of GL-PUSCH frequency resources and may select a time period. The WTRU may transmit data on a GL-PUSCH using the selected GL-PUSCH frequency resources during the selected time period. The WTRU may also monitor for hybrid automatic repeat request acknowledgement (HARQ-ACK) based on the selected GL-PUSCH frequency resources. The WTRU may monitor for the DCI during a fixed time window.

Abstract: A method and apparatus for supporting communication buffer status reports (BSRs) are disclosed. A wireless device may receive from an eNode-B a first indication indicating a logical channel group and at least one associated priority. The wireless device may produce a BSR associated with first data, which may include an indication associated with the logical channel group and an index indicating an amount of the first data. The wireless device may transmit the BSR to an eNode-B. Then, the wireless device may receive allocation information for transmission to a wireless transmit/receive unit (WTRU) group. Further, the wireless device may transmit at least a portion of the first data to the WTRU group over a logical channel in the logical channel group. Also, the BSR may further include a plurality of indications associated with a respective plurality of logical channel groups.