This disclosure provides methods, devices and systems for acknowledgement and retransmission, and more specifically, to methods, devices and systems that enable a secondary wireless channel to provide acknowledgements of data transmitted on a primary wireless channel concurrently with the reception of additional data on the primary wireless channel. In some implementations, a transmitting device may transmit wireless packets including multiple codewords to a receiving device via a first wireless channel. The receiving device may attempt to decode the received codewords based on primary information in the codewords. The receiving device may then transmit to the transmitting device, via a second wireless channel, a codeword acknowledgement that identifies codewords that the receiving device did not successfully decode. The transmitting device may then transmit parity information to the receiving device via the first wireless channel that aids the receiving device in decoding the identified codewords.

A first wireless device measures a channel busy ratio (CBR). Sidelink control information is received from a second wireless device, via a physical sidelink control channel (PSCCH). The sidelink control information comprises: a number of demodulation reference signal (DMRS) antenna ports; and resource assignment of a physical shared channel (PSSCH) received in one or more first resources. A first reference signal received powers (RSRPs) for a first DMRS antenna port of the PSSCH is measured. A second RSRP of the PSSCH is determined based on: the first RSRP, the number of DMRS antenna ports, and the CBR. One or more second resources are selected, based on the second RSRP of the PSSCH, for transmission within a set of candidate resources. One or more transport blocks are transmitted via the one or more second resources.

Certain aspects of the present disclosure provide techniques for sounding reference signal (SRS) frequency hopping enhancements. An example method performed by user equipment generally includes determining a first sounding reference signal (SRS) frequency hopping pattern for transmitting one or more SRSs; determining an antenna switch will occur during the transmission of the one or more SRSs; determining a second SRS frequency hopping pattern for transmitting the one or more SRSs, wherein determining the second SRS frequency hopping pattern comprises using the first SRS frequency hopping pattern to generate the second SRS frequency hopping pattern based on the determined antenna switch; and transmitting a first set of SRSs of the one or more SRSs according to the first SRS frequency hopping pattern and transmitting a second set of SRSs of the one or more SRSs according to the second SRS frequency hopping pattern.

The invention includes a method performed by a user equipment, UE, for selecting a directional beam for a random access procedure in a wireless network comprising: performing a plurality of directional listen-before-talk, LBT, procedures in a respective plurality of different directions associated with a respective plurality of beams, determining respective first metrics based on received power of respective reference signals associated with the respective beams, determining respective second metrics based on channel occupancy, CO, or LBT failures in the respective beams and selecting one of the beams to be used for the random access procedure based on the first metrics and the second metrics. The invention further includes a complementary method performed by a network node, as well as a UE and a network node configured to perform operations corresponding to such methods.

Disclosed herein is a method for transmitting, by a terminal, a sounding reference signal (SRS). The terminal receives a grant for uplink multiple subframes from a base station. The terminal determines a first subframe for an SRS transmission of the terminal among the uplink multiple subframes on the basis of SRS transmission position information received from the base station. Further, the terminal transmits the SRS in the first subframe.

Methods, systems, and devices for wireless communications are described. A transmitting device may select a scrambling sequence to use per symbol to reduce variance in a non-linearity parameter for a power amplifier (PA) output between a data symbol and a pilot symbol based on a PA model for at least one pilot symbol or one or more parameters of the model. The receiving device may indicate a capability to blindly estimate the scrambling sequence the transmitting device selected to the transmitting device. If the transmitting device does not receive the capability message from the receiving device or if the capability message indicates the receiving device is not capable of blind estimation, the transmitting device may indicate the selected scrambling sequence to the receiving device. Otherwise, the transmitting device may not indicate the selected scrambling sequence to the receiving device, and the receiving device may blindly estimate the scrambling sequence.

Method and user equipment (UE) are provided for scheduling with multiple cells. In particular, a UE can connect to a plurality of cells in a network. The UE can determine a specific slot for receiving a CSI-RS from a first cell. An index of the specific slot is n+X+L while n is an index of a slot for receiving a DCI from a second cell, X is a slot offset for triggering the CSI-RS and L includes parameters associated with SCSs of the first cell and the second cell. The UE can receive the CSI-RS from the first cell in the specific slot.

A communication method and a system for converging a 5th-generation (5G) communication system for supporting higher data rates beyond a 4th-generation (4G) system with a technology for Internet of things (IoT) are provided. The disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as a smart home, a smart building, a smart city, a smart car, a connected car, health care, digital education, a smart retail, security and safety services. The disclosure provides a method and an apparatus for efficient transmission and reception of control information in a sidelink communication.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive a synchronization signal block (SSB) including a physical layer cell identifier (PCI), where one or more resource elements carrying the SSB overlap with resource elements carrying a downlink shared channel associated with another PCI. The PCIs may be for a serving cell or another cell, such as a non-serving cell. The UE may also receive one or more demodulation reference signals (DMRSs) in the one or more resource elements in the downlink shared channel. The UE may determine whether overlap is permitted between the resource elements by comparing the PCIs of the SSB and the downlink shared channel. In some examples, once the UE determines whether resource element overlap is permitted, the UE may process the DMRSs.

In an aspect, the present disclosure includes a method, apparatus, and computer readable medium for wireless communications for generating, by a network entity for one or more user equipments (UEs), a downlink control information (DCI) for modifying a transmission scheme of the one or more UEs, the DCI including at least one hybrid automatic repeat request (HARQ) process number; and transmitting, by the network entity to the one or more UEs, the DCI including the at least one HARQ process number.