Methods, systems, and devices are described for fountain hybrid automatic repeat request (HARD) for reliable low latency communication. A wireless device may transmit a data block based on a low latency operational mode. The device may then transmit a number of redundancy versions of the data block prior to determining whether an acknowledgement (ACK) has been received. In some examples the ACK may be an augmented ACK, which may be based on the number of redundancy versions received prior to successfully decoding the data block, and which may include an additional resource request. In some examples, the device may select an updated modulation and coding scheme (MCS) based on the augmented ACK. In some examples, the device may increase a number of frequency resources (e.g., component carriers) used for transmission based on the augmented ACK.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may be scheduled to send uplink data to a base station using a particular transmission length provided by the base station. The UE may send multiple repetitions of the uplink data to the base station using transmissions that have varying lengths. The UE may determine a transmit power based on the length provided by the base station and use that transmit power for transmitting the repetitions, regardless of the actual lengths of the repetitions.

Certain specific examples are directed to or involve a plurality of vehicular communication stations including a first type and a second type which communicate over a shared communications channel characterized by a common RF frequency band. The stations may also include at least one of the plurality of vehicular communication stations broadcasting a set of vehicle-specific data over the shared communication channel for reception by the first type according to a first wireless communication protocol and concurrently for reception by the second type according to a second different wireless communication protocol. The broadcast may include a plurality of repetitive consecutive transmissions of the set of vehicle-specific data which may allow for improved range extension and reliability. Each of the repetitive consecutive transmissions may be formatted consistent with the first wireless communication protocol.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive a first transmission including encoded bits of a data packet and a second transmission including some or all of the encoded bits of the data packet. The first transmission associated with a first limited buffer rate matching (LBRM) configuration and the second transmission may be associated with a second LBRM configuration. The UE may process the first transmission and the second transmission based on the first LBRM associated with the first transmission being different than the second LBRM associated with the second transmission.

The present disclosure relates to a user equipment, a network node and respective communication methods for a user equipment and a network node. A according to some embodiments, a user equipment comprises a transceiver which, in operation, receives data on a plurality of downlink shared channels, the data received on the plurality of downlink shared channels being respectively the same data, and circuitry which, in operation, decodes the data, generates an indicator which indicates whether or not the data has been successfully decoded using the plurality of downlink shared channels. The transceiver, in operation, transmits the indicator on at least one of a plurality of uplink control channels associated respectively with the plurality of downlink shared channels.

A method and apparatus for sidelink hybrid automatic repeat request (HARQ) feedback and resource pool selection is provided. When user equipment (UE) autonomous resource selection is configured, a wireless device selects a resource pool configured with physical sidelink feedback channel (PSFCH) resources, among one or more resource pools allowed for a logical channel, based on i) sidelink data being available in the logical channel, ii) any resource pool being not selected for the logical channel, and iii) hybrid automatic repeat request (HARQ) feedback being enabled for the logical channel.

Disclosed are example embodiments of systems and methods for hybrid automatic repeat request (HARQ). An example method includes performing a first HARQ compression to reduce a number of HARQ bits, the HARQ compression comprising one of a unified HARQ compression and a block-wise HARQ compression. Optionally, the example method further includes performing a second HARQ compression to further reduce the number of HARQ bits to a compressed number of HARQ bits. One of the first HARQ compression and the second HARQ compression include the unified HARQ compression and another of the first HARQ compression and the second HARQ compression comprising the block-wise HARQ compression. The example method also includes saving the compressed HARQ data to a DDR storage.

Systems and methods for multiple Downlink Control Information (DCI) based Physical Downlink Shared Channel (PDSCH) scheduling are disclosed herein. In one embodiment, a method performed by a User Equipment (UE) comprises receiving first and second Physical Downlink Control Channels (PDCCHs) carrying first and second DCIs in first and second Control Resource Sets (CORESETs) in first and second time periods (t1, t2), respectively, wherein t1≤t2. The method further comprises receiving first and second PDSCHs scheduled by the first and second DCIs in third and fourth time periods (t3, t4), respectively, wherein the first and second PDSCHs are associated with a same Hybrid Automatic Repeat Request (HARQ) process and a same Transport Block (TB), and t3≤t4. The method further comprises sending first and second HARQ ACK/NACKs in first and second Physical Uplink Control Channel (PUCCH) resources in fifth and sixth time periods (t5, t6), respectively, wherein t5≤t6 and t4≤t5.

Aspects relate to techniques for delaying accept request messages for sidelink network coded communication. A network coding device can receive from a transmitting wireless communication device a sidelink transmission including a packet and a network coding request flag requesting the network coding device perform retransmission(s) of the packet. The network coding device can then receive feedback information for the first packet from a receiving wireless communication device that received the packet at a first time. In addition, the network coding device can transmit an accept request message to the transmitting device indicating whether the network coding device accepts performing retransmission(s) of the packet at a second time different than the first time.

Systems, methods, and instrumentalities are disclosed for receiver feedback in wireless systems. Receiver feedback format, content, type and/or timing may be determined as a function of, for example, at least one of a type of soft-combining processing to apply in a HARQ process, a HARQ operating point for the HARQ process, one or more reference transmissions for controlling a type of HARQ feedback for the HARQ process, and a feedback suppression parameter for one or more transmissions in a sequence associated with the HARQ process or a transport block (TB). Uniform and non-uniform CB-to-CBG mapping may be provided (e.g., by a WTRU) based on, for example, one or more parameters, interference and channel conditions and/or a probability of or actual pre-empting transmissions. A CB to CBG mapping indication may be provided, for example, in support of selecting a CB to CBG mapping from multiple CB to CBG mappings. Intra- and inter-WTRU interference/preemption indications may be provided.