Abstract: Methods, systems, and devices for wireless communication are described. A user equipment (UE) may receive, from a base station, a downlink transmission in a radio frequency spectrum band and may identify reference resources in the downlink transmission for computing a channel state information (CSI) report. The UE may generate the CSI report based at least in part on the identified reference resources and transmit, in the radio frequency spectrum band, the CSI report in a random access request message to the base station. The base station may receive the request message and identify CSI associated with the band based at least in part on the CSI report included in the random access request message. The base station may transmit, to the UE, a random access response message based at least in part on the identified CSI in the radio frequency spectrum band.

Abstract: Techniques are described for wireless communication. An orthogonal frequency-division multiple access (OFDMA) configuration of an uplink channel is identified for communications in an unlicensed radio frequency spectrum band. An OFDMA waveform is generated based on the identified OFDMA configuration. The OFDMA waveform is communicated in a signal in the unlicensed radio frequency spectrum band. A virtual cell identifier of a first base station may be associated with transmissions between the first base station and a first user equipment (UE). A set of common resource blocks may be identified for transmission of a demodulation reference signal (DM-RS) between the first base station and the first UE. A configuration of an uplink channel may be dynamically selected for uplink communications in an unlicensed radio frequency spectrum band. A waveform may be generated based on the selected configuration. The waveform may be communicated in a signal in the unlicensed radio frequency spectrum band.

Abstract: Techniques are described for wireless communication. A first method may include receiving at a user equipment (UE) over an unlicensed radio frequency spectrum band an indication of a time window associated with a transmission of a synchronization signal, and monitoring the unlicensed radio frequency spectrum band during the time window to receive a synchronization signal from a base station. A second method may include transmitting an indication of a time window associated with a transmission of a synchronization signal; performing a plurality of clear channel assessments (CCAs) on an unlicensed radio frequency spectrum band during the time window; and transmitting the synchronization signal over the unlicensed radio frequency spectrum band at a transmission time during the time window. The transmission time may be based at least in part on a result of at least one of the CCAs.

Abstract: Techniques are described for wireless communication. An orthogonal frequency-division multiple access (OFDMA) configuration of an uplink channel is identified for communications in an unlicensed radio frequency spectrum band. An OFDMA waveform is generated based on the identified OFDMA configuration. The OFDMA waveform is communicated in a signal in the unlicensed radio frequency spectrum band. A virtual cell identifier of a first base station may be associated with transmissions between the first base station and a first user equipment (UE). A set of common resource blocks may be identified for transmission of a demodulation reference signal (DM-RS) between the first base station and the first UE. A configuration of an uplink channel may be dynamically selected for uplink communications in an unlicensed radio frequency spectrum band. A waveform may be generated based on the selected configuration. The waveform may be communicated in a signal in the unlicensed radio frequency spectrum band.

Abstract: Methods, systems, and devices for wireless communications are described. A wireless device may identify a set of power configurations for a plurality of communications with at least one target device. The set of power configurations may be based at least in part on a type of signal, a type of channel, a parameter of the wireless device, a parameter of the target device, or a combination thereof. The wireless device may then determine a duplexing mode for the plurality of communications based at least in part on the set of power configurations. The duplexing mode may be, for example, a full duplex mode or a half-duplex mode. The wireless device may then transmit the plurality of communications to and/or receive the plurality of communications from the at least one target device according to the set of power configurations and the selected duplexing mode.

Abstract: Methods, systems, and devices are described for providing allocations and signaling for different types of communications within a wireless communication system. An eNB and/or a UE may be configured to operate within the wireless communication system using two or more different types of communications. The different types of communications may differ, for example, based on round trip time (RTT) between transmission and acknowledgment of receipt of the transmission, a transmission time interval (TTI) for wireless transmissions, and/or duty cycle timing of wireless transmissions. Reserved resources within a system bandwidth may be identified for a first type of communications, and all or a portion of remaining resources within the system bandwidth may be allocated for other communications that may differ from the first type of communications based on, for example, RTT, TTI, and/or duty cycle timing.

Abstract: Methods, systems, and devices for wireless communications (e.g., vehicle to everything systems) are described relating to an adaptive design of demodulation reference signals (DMRS) density based on user equipment (UE) velocity. A UE may send assistance information to a transmitting UE to help identify a DMRS pattern based on the relative speed between the two UEs. Also, the transmitter may determine the adaptive DMRS pattern based on its speed without information of the receiver's speed. The transmitter may indicate the adaptive DMRS pattern in control information to the receiver. A base station may receive assistance information, and the base station may determine the adaptive DMRS pattern to be used by the transmitting UE based on the received assistance information and then indicate the adaptive DMRS pattern to the transmitting UE. A UE may determine an adaptive DMRS pattern to use based on feedback from the receiving UE.

Abstract: Methods, systems, and devices are described for hierarchical communications and low latency support within a wireless communications system. An eNB and/or a UE may be configured to operate within the wireless communications system which is at least partially defined through a first layer with first layer transmissions having a first subframe type and a second layer with second layer transmissions having a second subframe type. The first subframe type may have a first round trip time (RTT) between transmission and acknowledgment of receipt of the transmission, and the second layer may have a second RTT that is less than the first RTT. Subframes of the first subframe type may be multiplexed with subframes of the second subframe type, such as through time division multiplexing. In some examples symbols of different duration may be multiplexed such that different symbol durations coexist.

Abstract: Methods and apparatuses for adaptive subcarrier spacing in wireless communication networks are described. For example, the described aspects include transmitting, from the UE to a network entity, a first PRACH transmission with a first subcarrier spacing; determining, by the UE, that the first PRACH transmission to the network entity is not successful; and transmitting, from the UE, a second PRACH transmission with a second subcarrier spacing in response to determining that the first PRACH transmission is not successful, wherein the first subcarrier spacing is different from the second subcarrier spacing.

Abstract: Techniques for transmitting and receiving wireless communications over an unlicensed radio frequency spectrum band are disclosed, including techniques for transmitting and receiving service information blocks over the unlicensed radio frequency spectrum band, techniques for gaining access to the unlicensed radio frequency spectrum band by performing extended clear channel assessments (eCCAs), techniques for transmitting and receiving synchronization signals and reference signals over the unlicensed radio frequency spectrum band, techniques for communicating locations of reference signals, and techniques for communicating availability of certain resources to be combined across multiple different transmissions.

Abstract: Certain aspects of the present disclosure generally relate to wireless communication. More particularly, certain aspects of the present disclosure relate to early termination of a downlink channel repetition transmission, early termination of an uplink channel repetition, and/or determination of a plurality of beams for a repetition transmission. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications (e.g., vehicle to everything systems) are described relating to an adaptive design of demodulation reference signals (DMRS) density based on user equipment (UE) velocity. A UE may send assistance information to a transmitting UE to help identify a DMRS pattern based on the relative speed between the two UEs. Also, the transmitter may determine the adaptive DMRS pattern based on its speed without information of the receiver's speed. The transmitter may indicate the adaptive DMRS pattern in control information to the receiver. A base station may receive assistance information, and the base station may determine the adaptive DMRS pattern to be used by the transmitting UE based on the received assistance information and then indicate the adaptive DMRS pattern to the transmitting UE. A UE may determine an adaptive DMRS pattern to use based on feedback from the receiving UE.

Abstract: Methods, systems, and devices are described for low latency communications within a wireless communications system. An eNB and/or a UE may be configured to operate within the wireless communications system and may send triggers to initiate communications using a dedicated resource in a wireless communications network that supports transmissions having a first subframe type and a second subframe type, the first subframe type comprising symbols of a first duration and the second subframe type comprising symbols of a second duration that is shorter than the first duration. Communications may be initiated by transmitting a trigger from the UE or eNB using the dedicated resource, and initiating communications following the trigger. The duration of time between the trigger and initiating communications can be significantly shorter than the time to initiate communications using legacy LTE communications.

Abstract: Methods, systems, and devices are described for hierarchical communications and low latency support within a wireless communications system. An eNB and/or a UE may be configured to operate within the wireless communications system which is at least partially defined through a first layer with first layer transmissions having a first subframe type and a second layer with second layer transmissions having a second subframe type. The first subframe type may have a first round trip time (RTT) between transmission and acknowledgment of receipt of the transmission, and the second layer may have a second RTT that is less than the first RTT. Subframes of the first subframe type may be multiplexed with subframes of the second subframe type, such as through time division multiplexing. In some examples symbols of different duration may be multiplexed such that they different symbol durations coexist.

Abstract: Methods and apparatuses for adaptive subcarrier spacing in wireless communication networks are described. For example, the described aspects include transmitting, from the UE to a network entity, a first PRACH transmission with a first subcarrier spacing; determining, by the UE, that the first PRACH transmission to the network entity is not successful; and transmitting, from the UE, a second PRACH transmission with a second subcarrier spacing in response to determining that the first PRACH transmission is not successful, wherein the first subcarrier spacing is different from the second subcarrier spacing.

Abstract: Certain aspects of the present disclosure generally relate to wireless communication. More particularly, certain aspects of the present disclosure relate to early termination of a downlink channel repetition transmission, early termination of an uplink channel repetition, and/or determination of a plurality of beams for a repetition transmission. Numerous other aspects are provided.

Abstract: Methods and apparatuses are described in which an unlicensed spectrum is used for Long Term Evolution (LTE) communications. One method includes performing a clear channel assessment (CCA) for an unlicensed spectrum in a current gating interval to determine whether the unlicensed spectrum is available for a transmission in a next transmission interval, and gating OFF the transmission in the unlicensed spectrum for the next transmission interval when the determination is that the unlicensed spectrum is unavailable.

Abstract: Methods and apparatuses are described for wireless communications. A first method includes transmitting a first Orthogonal Frequency-Division Multiple Access (OFDMA) communications signal to a wireless node in a licensed spectrum, and transmitting, concurrently with the transmission of the first OFDMA communications signal, a second OFDMA communications signal to the wireless node in an unlicensed spectrum. A second method includes receiving a first Orthogonal Frequency-Division Multiple Access (OFDMA) communications signal from a wireless node in a licensed spectrum, and receiving, concurrently with the reception of the first OFDMA communications signal, a second OFDMA communication signal from the wireless node in an unlicensed spectrum.

Abstract: Methods, systems, and devices for wireless communications are described. A wireless device may identify a set of power configurations for a plurality of communications with at least one target device. The set of power configurations may be based at least in part on a type of signal, a type of channel, a parameter of the wireless device, a parameter of the target device, or a combination thereof. The wireless device may then determine a duplexing mode for the plurality of communications based at least in part on the set of power configurations. The duplexing mode may be, for example, a full duplex mode or a half-duplex mode. The wireless device may then transmit the plurality of communications to and/or receive the plurality of communications from the at least one target device according to the set of power configurations and the selected duplexing mode.

Abstract: Methods, systems, and devices for wireless communication are described. A user equipment (UE) may receive, from a base station, a downlink transmission in a radio frequency spectrum band and may identify reference resources in the downlink transmission for computing a channel state information (CSI) report. The UE may generate the CSI report based at least in part on the identified reference resources and transmit, in the radio frequency spectrum band, the CSI report in a random access request message to the base station. The base station may receive the request message and identify CSI associated with the band based at least in part on the CSI report included in the random access request message. The base station may transmit, to the UE, a random access response message based at least in part on the identified CSI in the radio frequency spectrum band.