Abstract: Methods, systems, and devices for wireless communication are described. Some wireless communications systems (e.g., New Radio (NR) systems) may support the dynamic configuration of time intervals (or slots) for communication in a specific link direction (e.g., uplink, downlink, sidelink, etc.). In such cases, a base station may dynamically allocate time intervals (or slots) for broadcast or multicast data (e.g., via a physical downlink control channel (PDCCH)) based on the dynamically determined configuration of certain time intervals (or slots). The dynamic allocation of resources for broadcast or multicast data may ensure that broadcast or multicast data is not scheduled to be transmitted during time intervals configured for uplink communication. In some cases, the broadcast or multicast data may be transmitted on a portion of a system bandwidth that is frequency division multiplexed with another portion of the system bandwidth allocated for mobile broadband (MBB) communications.

Abstract: Methods, systems, and devices for wireless communication are described that support sounding reference signal (SRS) transmission in low latency wireless transmissions. A set of shortened transmission time intervals (sTTIs) for uplink transmissions of a first wireless service may be identified; the set of sTTIs located within subframe time boundaries of a subframe of a second wireless service with a longer TTI than the sTTIs. Two or more sTTIs within the set of sTTIs may be used for SRS transmissions within the subframe time boundaries.

Abstract: Methods, systems, and devices for wireless communication are described. Data may be received during transmission time intervals (TTIs) that have a short duration relative to other TTIs. The short-duration TTIs may occur within or overlap a longer duration TTI, such as a subframe. Feedback responsive to the data may be generated and assigned for transmission during an uplink TTI according to a feedback timing or delay, which may be selected to reduce latency or balance the payload size of uplink messages sent during the assigned uplink TTI. Data and feedback assignments in short-duration TTIs may be configured based on a time division duplexing (TDD) configuration for some TTIs (e.g., subframes). TTIs that are a Long Term Evolution (LTE) subframe, an LTE slot, and a duration of two LTE symbol periods may be supported. Portions of special TTIs may be used for transmissions according to shorter-duration TTIs.

Abstract: This disclosure provides systems, devices, apparatus and methods, including computer programs encoded on storage media, for interference measurement and reporting by a UE. The interference measurement can be self-initiated by the UE or based on a request received from a BS. To measure the interference, the UE transmits a first signal in UL resources to a first BS concurrently with receiving a second signal in DL resources from one of the first BS or a second BS. The received second signal includes interference associated with the transmitted first signal. Based on the received second signal, the UE determines a level of the interference that is associated with the transmitted first signal. Information associated with the level of the interference is then transmitted to the first BS, such as an indication of a guard band that is to be incorporated between the UL resources and the DL resources.

Abstract: Methods, systems, and devices for wireless communication are described. A user equipment (UE) may transmit uplink (UL) messages in unlicensed spectrum with a reduced UL timing delay. The UL timing delay may be reduced by using a shortened transmission time interval (TTI) (e.g., a TTI that is reduced in duration relative to other TTIs in the system or in a legacy system) or by reducing the number of TTIs between a grant and the corresponding UL message. The reduced UL timing delay may decrease the likelihood that the UE will wait for a subsequent transmit opportunity (TxOp) to transmit the UL message. In some cases, the reduced UL timing delay corresponds to a reduced hybrid automatic repeat request (HARQ) processing delay. In some cases, a time difference (e.g., measured in TTIs) between a measurement reference TTI a corresponding channel state information (CSI) report may also be reduced.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may identify one or more radio frequency (RF) spectrum bands for full-duplex communications, and may signal an indication of the UE's capability to support full-duplex communications for each RF spectrum band. The UE may further receive one or more configurations for full-duplex communications, which, in some examples, may be based on the UE's indicated capabilities. As an example, the UE may identify a guard band configuration for full-duplex communications, where the guard band configuration may be based on one or more aspects of resources used for the full-duplex communications. In other cases, the UE may identify a transmission hopping or antenna switching configuration for full-duplex communications. In any case, the UE may communicate with a base station in accordance with the one or more configurations and the UE's capabilities.

Abstract: Techniques are described for wireless communication. A first method includes inserting channel or interference estimation modulation symbols into a sequence of data modulation symbols; performing a discrete Fourier transform (DFT) on a group of modulation symbols in the sequence of data modulation symbols, the group of modulation symbols including at least one of the channel or interference estimation modulation symbols; and generating a single-carrier frequency domain modulated (SC-FDM) symbol stream based at least in part on an output of the DFT.

Abstract: Methods, systems, and devices for wireless communication are described that provide for reduced timing between certain downlink communications and responsive uplink communications relative to certain legacy systems (e.g., legacy LTE systems). A user equipment (UE) or base station may be capable of operating using two or more timing configurations that each include an associated time period between receipt of a downlink communication (e.g., a grant of uplink resources or shared channel data) and a responsive uplink communication (e.g., an uplink transmission using the granted uplink resources or feedback of successful reception of the shared channel data). In cases where a UE or base station are capable of two or more timing configurations, a timing configuration for a transmission may be determined and the responsive uplink communication transmitted according to the determined timing configuration.

Abstract: A base station is disclosed that includes two separated antenna arrays. In a TDD mode of operation, both arrays are used for either transmit or receive. In a sub-band full-duplex mode of operation, one array is used to transmit downlink symbols while the remaining array is used to receive uplink symbols.

Abstract: Methods, systems, and devices for wireless communication are described. A user equipment (UE) may determine separate uplink (UL) power limitations for multiple transmission time interval (TTI) durations based on distinct power control parameters. In some cases, an adjustment factor or a power backoff may be applied to communications using one TTI duration to ensure that total transmit power does not exceed a threshold. The UE and the serving base station may also identify one or more demodulation reference signal (DMRS) windows. UL data transmissions may be demodulated based on a DMRS sent during the same window. Transmit power control (TPC) commands may be applied at the beginning of each window. However, if an UL transmission is scheduled at the beginning of the window, the UE may wait until a DMRS transmission or until no more transmissions are scheduled for the window before applying the TPC adjustment.

Abstract: Noise and interference may be estimated at a user equipment (UE) in a system that may support transmissions having different transmission time intervals (TTIs). The UE may perform a channel estimation for a first set of transmissions having a first TTI based at least in part on an estimated interference from a second set of transmissions having a second TTI that is shorter than the first TTI. The UE may perform channel estimation for orthogonal frequency division multiplexing (OFDM) symbols of the first set of transmissions. The first set of transmissions may then be demodulated based at least in part on the channel estimation for the first set of transmissions. Noise and interference may also be estimated based on one or more null tones within one or more OFDM symbols of the allocated resources.

Abstract: Control information may be transmitted for different TTI lengths. Different control information for the different TTIs may be transmitted using control channel resources that are established for communication of control information, such as a physical downlink control channel (PDCCH), for example. Control information for a first TTI may be located in a first set of resources, and control information for a second TTI may be located in a second set of resources. The first set of resources may be located within a first search space that may be searched by a user equipment (UE) to identify the first control information. The second set of resources may be located within a second search space that may be searched by the UE to identify the second control information.

Abstract: Systems, methods, and apparatuses are described for wireless communication, including for hybrid automatic repeat request (HARQ) feedback in a system that supports communications using transmission time intervals (TTIs) of different durations. A base station may identify a user equipment's (UE) capability to provide HARQ feedback for transmissions that use TTIs of a shorter duration relative to other TTIs supported in the system. The base station may select a HARQ timing mode based on the capability of the UE and may indicate the selected HARQ timing mode to the UE. The base station may then transmit one or more data transmissions to the UE using the reduced TTIs. The UE may respond with HARQ feedback based on the HARQ timing mode. The HARQ timing mode may be based on different response times based on the location of the data transmission within a TTI or relative to data transmission in other TTIs.

Abstract: Methods, systems, and devices for wireless communication using various patterns of data and reference signals are described. For example, in a system that supports operation using different duration transmission time intervals (TTIs), a base station may initiate communication with a user equipment (UE) or between two UEs, and UEs may communicate with the base station or with one another using an indicated pattern of data and reference signals. The base station may send a downlink control message indicating a transmission pattern selected from a set of patterns. UEs may identify the pattern based on the indicator and decode a sequence of data and reference signals based on the pattern. In some examples, the sequence may include a set of TTIs, which may have a shorter duration than other TTIs.

Abstract: Aspects described herein relate to determining that a time division is for receiving a synchronization signal block (SSB) and for a random access occasion (RO) for transmitting a random access preamble in full duplex (FD) communications, and based on the determining, at least one of receiving the SSB or transmitting the random access preamble in the RO during the time division.

Abstract: Methods, systems, and devices for wireless communication are described. In one example, an indication in a first control message in a control region of a first transmission time interval (TTI) identifies a data region of the first TTI. A data region of the second TTI may be identified based on a grant of resources received in a second control message of a second TTI, where the data region of the first TTI and the control region of the second TTI are frequency division multiplexed with the data region of the second TTI. Other examples include a downlink grant at the beginning of a control region and uplink grants at the end of the control region. In other examples, a downlink grant for a user equipment (UE) may include an indication of resources allocated to the UE in that resource block and a second resource block.

Abstract: Described techniques provide for prioritization of radio bearers and logical channels based on mixed transmission time interval (TTI) durations or numerologies of the bearers or logical channels. Two or more bearers may be identified for uplink data transmission that carry data to be transmitted using different TTI durations or numerologies. Each bearer may be prioritized based on the associated bearer type, TTI duration or numerology, or combinations thereof. Additionally, one or more logical channels may be associated with one or more bearers, and also prioritized based on the associated bearer type, TTI duration or numerology, or combinations thereof. A buffer status report (BSR) may be generated that has one or more portions associated with the different priorities of bearers or logical channels. Buffer information associated with the higher priority bearers or logical channels may be provided ahead of buffer information associated with lower priority bearers or logical channels.

Abstract: Coordinated wireless communications using multiple transmission time intervals (TTIs) are described. Multiple TTIs may include a first TTI and a second TTI, the second TTI having a shorter duration than the first TTI. One or more parameters may be determined for communications using the first TTI and the second TTI. A first parameter of the determined parameters for the second TTI may be associated or linked with a corresponding parameter of the first TTI, and communications using the first TTI or the second TTI may be performed using the first parameter. Wireless network nodes using the first TTI may form a CoMP cooperating set, and wireless network nodes using the second TTI may for another CoMP cooperating set, and the first parameter may be applied to each of the CoMP cooperating sets.

Abstract: Techniques are described for wireless communication. A first method includes transmitting a first signal to indicate accessing a first channel in a radio frequency spectrum band, and transmitting information with the first signal in the radio frequency spectrum band. A second method includes winning contention to access a radio frequency spectrum band, and after the winning contention to access the radio frequency spectrum band, transmitting a first signal to align a starting point of a second signal with a reference boundary associated with the radio frequency spectrum band. A third method includes winning contention to access a radio frequency spectrum band during a first frame period, the first frame selected from a plurality of different frame periods, and transmitting a signal at a periodicity during one or more subframes of the first frame period for each of the plurality of different frame periods.

Abstract: Various aspects described herein relate to receiving wireless communications from an access point, determining resources of the wireless communications associated with a search space for control information in the received wireless communications, and performing one or more of a set of blind decodes over the search space to decode at least low latency control information associated with a low latency communication technology, wherein the low latency communication technology utilizes a transmission time interval (TTI) having a duration that is less than a subframe of a legacy communication technology.