A base station is configured to determine a sounding reference signal (SRS) configuration that has a plurality of cyclic shifts for a comb 8 SRS, a plurality of user equipment (UE) ports for transmitting the comb 8 SRS and a mapping of the plurality of cyclic shifts to the plurality of UE ports. The base station is further configured to transmit the SRS configuration to the UE.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a base station may transmit a message, to a user equipment (UE), instructing the UE to activate or update a reference signal (RS) corresponding to an uplink communication transmitted by the UE. The base station may communicate with the UE, after a time period, using a beam configuration of the base station that corresponds to a beam configuration of the UE for transmitting the RS, the time period being based at least in part on a determination of whether the UE identified the beam configuration of the base station. Numerous other aspects are provided.

One embodiment of the present specification provides a method by which a machine type communication (MTC) device configured to operate only in some bands among the system bands of a cell transmits a demodulation reference signal (DMRS) for the demodulation of uplink data. The method can comprise the steps of: selecting any one DMRS sequence among a plurality of sets of DMRS sequences having a length M according to a group hopping number and allocation area information of a sub-physical resource block (PRB), when an uplink signal is transmitted through the sub-PRB including the M number of subcarriers which is less than twelve subcarriers; and mapping the selected DMRS sequence on the M number of subcarriers of the sub-PRB, and transmitting the same.

The present invention is designed to suitably reduce the degradation of spectral efficiency even when communication is performed using a waveform of a single-carrier transmission scheme. According to one aspect of the present invention, a user terminal has a receiving section that receives a downlink control signal, which schedules transmission of a data signal in accordance with a waveform that is based on a single-carrier transmission scheme, and a transmission section that transmits a sounding reference signal, which is different from an uplink sounding reference signal used in existing LTE and which has a wider transmission bandwidth than the data signal, by using the waveform based on the single-carrier transmission scheme.

A method and an apparatus for uplink transmission in a communication system. An operation method of a terminal includes: receiving, from a base station, first SFI information indicating n flexible symbol(s); receiving, from the base station, second SFI information re-indicating m symbol(s) of the n flexible symbol(s) as uplink (UL) symbol(s); and transmitting an SRS to the base station through the m symbol(s) re-indicated as a UL symbol among the n flexible symbol(s) indicated as a flexible symbol. Therefore, performance of the communication system can be improved.

Apparatuses, methods, and systems are disclosed for communication configuration selection. One apparatus includes a receiver that receives configuration information for multiple communication configurations. The configuration information corresponds to services having different performance requirements, and the performance requirements include latency, reliability, peak data rate, efficiency overhead, control overhead, system capacity, or some combination thereof. The apparatus also includes a processor that selects a communication configuration of the multiple communication configurations. The apparatus communicates using the selected communication configuration.

Systems and methods are disclosed herein for providing aperiodic Sounding Reference Signal (SRS) triggering in a wireless system. Embodiments of a method performed by a wireless device and corresponding embodiments of a wireless device are disclosed. In some embodiments, a method in a wireless device for triggering aperiodic SRS comprises receiving a first SRS configuration for a first type of aperiodic SRS transmission and a second SRS configuration for a second type of aperiodic SRS transmission. The method further comprises receiving downlink control information comprising a parameter for triggering an aperiodic SRS transmission and determining whether to use the first SRS configuration or the second SRS configuration. The method further comprises transmitting an aperiodic SRS transmission in accordance with the determined SRS configuration. Embodiments of a method performed by a base station and corresponding embodiments of a base station are also disclosed.

Methods, systems, and devices for wireless communications are described. A codebook adaptation may be performed for a flexible user equipment (UEs) to determine a codebook for a physical configuration of the UE. For example, if the UE determines that the physical configuration does not correspond to a pre-loaded codebook in its memory, the UE may provide information about the physical configuration to a base station to determine a corresponding codebook. Additionally, the UE may request that the base station provide channel information to assist with the codebook determination. In some cases, this request may indicate for the base station to allocate a specific number of channel state information reference signal symbols that the UE can use for the codebook determination. Additionally or alternatively, the UE may generate the codebook internally and then signal to the base station a request for a beam refinement procedure with the generated codebook.

A wireless device (e.g., a UE or a base station) may identify a first subcarrier mapping associated with one or more redundant subcarriers. The one or more redundant subcarriers may correspond to one or more UWs in a UW-OFDM waveform. The wireless device may identify a second subcarrier mapping associated with one or more reference signals. A simultaneous application of the first subcarrier mapping and the second subcarrier mapping may be associated with one or more collisions. The wireless device may modify at least one of the first subcarrier mapping or the second subcarrier mapping to eliminate the one or more collisions. The wireless device may generate the UW-OFDM waveform based on the modified at least one of the first subcarrier mapping or the second subcarrier mapping. The wireless device may transmit a signal based on the generated UW-OFDM waveform.

A method of selectively transmitting a positioning signal from a TRP includes: transmitting, unmuted, a first intra-slot positioning signal resource segment in a first slot of a transmission schedule in accordance with a muting configuration, the transmission schedule indicating which one or more resource elements to sound for transmitting at least a portion of the positioning signal, the muting configuration indicating whether to mute intra-slot positioning signal resource segments; and muting transmission by the TRP of a second intra-slot positioning signal resource segment in the first slot of the transmission schedule in accordance with the muting configuration.