Abstract: Methods, systems, and devices for addressing collisions of possible random access channel (RACH) occasions. A wireless transmit receive unit (WTRU) may receive an indication of semi-static UL/DL information including configuration of RACH occasions in a remaining minimum system information (RMSI) and an indication of one or more actually transmitted synchronization signal (SS) blocks. The WTRU may then assess whether there are RACH occasions based on the configuration information and determine whether any of the RACH occasions are valid, wherein the RACH occasion may be valid based on Based on the RACH occasion is after all actually transmitted SS blocks indicated and/or whether an SS block override is disabled or enabled. The WTRU may transmit a RACH in one or more of the RACH occasions that have been determined to be valid.

Abstract: Mechanisms may be used for aggregating acknowledgement (ACK), block ACK (BA) and/or short packets transmissions for multi-user (MU) wireless communication systems. Aggregation mechanisms may be used for uplink (UL) and/or downlink (DL) orthogonal frequency division multiple access (OFDMA), and/or UL/DL multiple-user multiple input multiple output (MU-MIMO) transmissions, for example. Multi-user short packets may be aggregated and/or simultaneously transmitted for DL, UL, or peer-to-peer (P2P) transmissions.

Abstract: Systems, methods, and instrumentalities are described herein that may be used for NOMA resource selection. Different types of NOMA resources may be configured by a network and selected by a WTRU based on rules, priorities, fairness, overloading factors, multiple access signature sizes, measurement results, payload sizes, and/or the like. Single-NOMA operations may be performed using DFT-invariant codewords. Multiple NOMA schemes may coexist with different codeword types and/or codeword sizes.

Abstract: A method may comprise receiving a first signal comprising first LDPC bits including systematic bits and parity bits and transmitting information indicating that the first signal was incorrectly received. A second signal comprising second LDPC bits may be received in response to the transmitting. The second signal may include LDPC bits according to a lifting size of an LDPC base graph.

Abstract: Methods, devices, and systems for physical random access channel (PRACH) access. A WTRU transmits a message to a gNB. The message includes a PRACH preamble from a first set. The method also includes performing a hidden node detection procedure prior to a random access response (RAR) window. The RAR window corresponds to the transmitted message. The method also includes attempting to receive a RAR in response to the transmitted message, during the RAR window. The method also includes retransmitting the message to the gNB, including a PRACH preamble from a second set, if the RAR is not received during the RAR window and a hidden node is detected; and retransmitting the message to the gNB, including a PRACH preamble from the first set, if the RAR is not received during the RAR window and the hidden node is not detected.

Abstract: A WTRU may include a memory and a processor. The processor may be configured to receive beam grouping information from a gNB or transmission and reception point (TRP). The beam grouping information may indicate a group of beams that the WTRU may report using group-based reporting. The group-based reporting may be a reduced level of reporting compared to a beam-based reporting. The group-based report may include measurement information for a representative beam. The representative beam may be one of the beams in the group or represents an average of the beams in the group. Alternatively, the representative beam may be a beam that has a maximum measurement value compared to other beams in the group. The group-based report may include a reference signal received power (RSRP) for the representative beam and a differential RSRP for each additional beam in the beam group.

Abstract: A method for transmitting system information on a PBCH is described herein. A transmission/reception point (TRP) may generate a concatenated master information block (MIB) transport block that includes information bits associated with system bandwidth information, timing information, system frame number (SFN), a beam sweeping configuration, and a control resource set (CORESET). The TRP may then attach at least 16 cyclic redundancy check (CRC) bits to the concatenated MIB and then prioritize the concatenated MIB and the at least 16 CRC bits based on content. The TRP may then perform channel coding of the prioritized concatenated MIB and the at least 16 CRC bits to produce coded bits using at least one polar encoder with a coding rate that is less than ?, perform rate matching via repetition on the coded bits, and then transmit the rate matched, coded bits on the PBCH of a radio frame.

Abstract: A method and apparatus for use in a wireless transmit receive unit (WTRU) for receiving and transmitting information blocks is disclosed. A WTRU receives transmitted broadcast information, the transmitted broadcast information including a first information block and a second information block. Based on information in the received second information block, the WTRU transmits a random access preamble. After the transmission of the random access preamble, the WTRU may receive a random access response. Based on information in the received random access response, the WTRU may transmit a message including control information indicating additional information blocks that the WTRU is requesting to receive. After transmission of the transmitted message, the WTRU may receive the additional information blocks. In an example, the transmitted broadcast information may be periodically transmitted broadcast information.

Abstract: A method may comprise transmitting a first signal derived from a first subset of a set of LDPC coded bits and transmitting a second signal derived from a second subset of the set of LDPC coded bits. The second subset may be selected from the set of LDPC coded bits based on a lifting size of an LDPC base graph. The method may further comprise receiving an indication of a first redundancy version. The transmitting the first signal may be in response to receiving the indication of the first redundancy version.

Abstract: Methods, devices, and systems for resource allocation are disclosed herein. Specifically, a wireless transmit receive unit (WTRU) may measure a reference signal received power (RSRP) level and a received signal strength indicator (RSSI) value of one or more resources in each of a plurality of patterns. The WTRU may exclude, from the selection, each pattern for which at least one resource in the pattern is reserved by another WTRU and has an RSRP greater than a threshold. On a condition that at least one of the plurality of patterns is not excluded, the WTRU may select a pattern with a lowest pattern RSSI value and a one or more resources satisfying a quality of service (QoS) requirement of data of the WTRU. The WTRU may then transmit the data of the WTRU using the selected pattern.

Abstract: Methods, systems, and apparatuses for use in wireless communication are disclosed. A method of communication on an unlicensed band may include detecting a Synchronization Signal/Physical Broadcast Channel (SS/PBCH) block comprising a demodulation references signal (DMRS), a synchronization signal (SS), and a PBCH payload. A SS/PBCH block index may be obtained from one of the DMRS and the PBCH payload. A cyclic rotation indicator may be obtained from the SS/PBCH block (e.g., from the DMRS, the SS, and/or the PBCH payload). A determination may be made that the cyclic rotation indicator indicates an on state and a time gap may be obtained from one of the DMRS and the PBCH payload, based on the determination. Frame timing may be determined based on the cyclic rotation indicator, the SS/PBCH block index, and the time gap.

Abstract: Methods and apparatus are described. A station includes a transceiver and a processor, which detect a trigger frame for an uplink (UL) multi-user (MU) transmission. The trigger frame includes a user information field with an allocation of one or more random access resource units (RUs) and a common information field with information to set high efficiency (HE) SIGNAL-A (HE-SIG-A) fields in the UL MU transmission. The transceiver and the processor generate an HE trigger-based (TB) physical layer protocol data unit (PPDU) and set an HE-SIG-A field in the HE TB PPDU using the information in the trigger frame. The transceiver and the processor select one of the one or more random access RUs and transmit the HE TB PPDU, using the selected one of the one or more random access RUs, a short inter-frame space after the trigger frame.

Abstract: A wireless transmit/receive unit (WTRU) may receive, from a base station, information concerning an association between synchronization signal/physical broadcast channel (SS/PBCH) block transmissions and physical random access channel (PRACH) resources. In an example, each SS/PBCH block transmission may be associated with a transmission beam of the base station. The WTRU may receive the SS/PBCH block transmissions and select one of the transmissions. Further, the WTRU may compare a reference signal received power (RSRP) associated with the selected transmission to a threshold. The WTRU may then determine between performing a random access procedure of a first type and a second type based on the comparison. Also, the WTRU may select a PRACH resource based on the selected transmission and the information concerning the association between the transmissions and the PRACH resources. Moreover, the WTRU may transmit a PRACH preamble, for the determined random access procedure, using the selected PRACH resource.

Abstract: Systems, methods, and instrumentalities associated with wake-up signals may be provided, e.g., for power saving. The systems, methods, and instrumentalities may include interference-free wake-up signal (WUS)/go-to-sleep signal (GOS) and/or ON/OFF keying (OOK) waveform enhancements. The systems, methods, and instrumentalities for interference-free WUS/GOS may include wake-up control signal format and content and/or user multiplexing and reference symbols for WUS/GOS signaling. The systems, methods, and instrumentalities for OOK waveform enhancements may include one or more of uniform WUS/GUS using time domain masking based OOK, OOK randomization, and/or using orthogonal frequency division multiplexing (OFDM) symbols with multiple subcarrier spacing values for OOK symbols.

Abstract: A WTRU may select sidelink unicast or groupcast to transmit data. If the WTRU selects sidelink unicast, the WTRU may select to use HARQ ACK/NACK feedback for the transmission. If the WTRU selects sidelink groupcast, either HARQ NACK or HARQ ACK/NACK may be selected depending upon one or more factors. The WTRU may select HARQ NACK or HARQ ACK/NACK depending upon one or more of: a number of WTRUs to receive the data; a condition of a channel associated with transmission; or a quality of service associated with transmission. The WTRU may select a first or second PSFCH format for feedback based upon one or more factors. The WTRU may select a first or second PSFCH format based upon one or more of: the selected sidelink unicast or groupcast; the selected HARQ NACK or HARQ ACK/NACK feedback; or a quality of service associated with the transmission.

Abstract: A wireless transmit/receive unit (WTRU) may utilize pre-configured rules for scaling power levels. Channels may be grouped based on a type of data to be transmitted. A power level of a channel from a group may be scaled using the pre-configured rules. A power level of a channel of a supplementary carrier may be scaled before another channel of a non-supplementary carrier.

Abstract: Systems, methods, and instrumentalities are disclosed for advanced coding on retransmission of data and/control information. The systems methods, and instrumentalities may include one or more of the following: chase combining for retransmission; incremental redundancy (IR) hybrid automatic repeat request (IR-HARQ); or incremental freezing (IF) HARQ. IF-HARQ may use lower coding rates and/or increased mother codeword length. IF-HARQ for retransmission with joint encoding and transmission of failed data and/or control message(s) (e.g., new control message(s)) may be used. This may include one or more of the following: increased priority for retransmission data and mapping retransmitted data to more reliable bit channels; or allocating more PC frozen bits for retransmitted data. A HARQ decision may be provided. For example, a decision may be made between the use of chase combining (CC) HARQ, IR-HARQ, or IF-HARQ. For IF-HARQ, additional decisions may be made.

Abstract: Methods and apparatus are described. A station includes a transceiver and a processor, which detect a trigger frame for an uplink (UL) multi-user (MU) transmission. The trigger frame includes a user information field with an allocation of one or more random access resource units (RUs) and a common information field with information to set high efficiency (HE) SIGNAL-A (HE-SIG-A) fields in the UL MU transmission. The transceiver and the processor generate an HE trigger-based (TB) physical layer protocol data unit (PPDU) and set an HE-SIG-A field in the HE TB PPDU using the information in the trigger frame. The transceiver and the processor select one of the one or more random access RUs and transmit the HE TB PPDU, using the selected one of the one or more random access RUs, a short inter-frame space after the trigger frame.

Abstract: Systems, methods, and instrumentalities are disclosed for interleaving coded bits. A wireless transmit/receive unit (WTRU) may generate a plurality of polar encoded bits using polar encoding. The WTRU may divide the plurality of polar encoded bits into sub-blocks of equal size in a sequential manner. The WTRU may apply sub-block wise interleaving to the sub-blocks using an interleaver pattern. The sub-blocks associated with a subset of the sub-blocks may be interleaved, and sub-blocks associated with another subset of the sub-blocks may not be interleaved. The sub-block wise interleaving may include applying interleaving across the sub-blocks without interleaving bits associated with each of the sub-blocks. The WTRU may concatenate bits from each of the interleaved sub-blocks to generate interleaved bits, and store the interleaved bits associated with the interleaved sub-blocks in a circular buffer. The WTRU may select a plurality of bits for transmission from the interleaved bits.

Abstract: An apparatus and method are described. The apparatus includes a transceiver and processor, which attach transport block (TB) level CRC bits to a TB, select an LDPC base graph (BG) based on a code rate (CR) and TB size of the TB including TB level CRC bits, determine a number of code blocks (CBs) to use for segmenting the TB including TB level CRC bits depending on the selected LDPC BG, determine a single CB size for each of the CBs based on the number of CBs, segment the TB including TB level CRC bits into the CBs based on the number of CBs and CB size, pad zeros to a last CB of the CBs in the segmented TB, attach CB level CRC bits to each CB in the segmented TB, encode each CB in the segmented TB using the selected LDPC base graph, and transmit the encoded CBs.