Abstract: Techniques are described for wireless communication. A method for wireless communication at a user equipment (UE) includes transmitting precoder selection signals from at least two antennas of the UE during performance of a random access procedure over a wireless network; and receiving, from the wireless network during the random access procedure, an indication of a refined precoding setting for the UE. A method for wireless communication at a network access device includes receiving, from a UE during a random access procedure performed by the UE, precoder selection signals from at least two antennas of the UE; identifying a refined precoding setting for the UE based at least in part on the received precoder selection signals; and transmitting an indication of the refined precoding setting to the UE.

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: Aspects of the present disclosure describe communicating control data based on reference signals in wireless communications. A timeline for transmitting uplink communications can be determined, where the timeline can relate to whether to process downlink communications based on at least one of a first type of reference signal (RS) or a second type of RS, a length or number of symbols in the reference signal, or a timing advance.

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.

Abstract: A register clock driver for a DDR5 memory is presented. A register clock driver (RCD) can include a logic having one or more input channels, each of the one or more input channels receiving input signals; and a plurality of ranked output ports associated with each of the one or more input channels, the logic providing the input signals received on each of the one or more input channels to the associated plurality of ranked output ports according to control signals. The RCD can operate in a default mode, wherein input signals from the input channels are output to both of the output ports associated with that channel, or can operate in a non-default mode where input signals from the input channels are sent to the appropriate ranked output port associated with that channel. In either case, unused signaling on the output ports is held high.

Abstract: Various aspects described herein relate to scheduling resources in wireless communications. In one aspect, communications can be established with a plurality of user equipment (UE). A set of the plurality of UEs as having an interference impact on one another that is less than a threshold can be determined. A first UE of the set of the plurality of UEs can be scheduled for downlink communications in a first transmission time interval (TTI), and a second UE of the set of the plurality of UEs can be scheduled for uplink communications in a second TTI that is adjacent in time to the first TTI. In another aspect, uplink communications for the first UE can be scheduled in a portion of the guard period TTI based at least in part on determining a timing advance of the first UE is less than a threshold.

Abstract: Aspects of the present disclosure relate to wireless communications and, more particularly, to synchronization for standalone long term evolution (LTE) broadcast. In one aspect, a method is provided which may be performed by a wireless device such as a base station (BS). The method generally includes providing unicast coverage to one or more user equipments (UEs) in a unicast coverage area within a larger coverage area, transmitting unicast data in one or more subframes, and transmitting synchronization signals within one or more of the broadcast subframes, wherein the broadcast signals are transmitted as single frequency network (SFN) transmissions synchronized with transmissions from one or more other base stations providing unicast coverage within the larger coverage area.

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 are described that identify an uplink transmission time interval (TTI) length for uplink transmissions, and a downlink TTI length for downlink transmissions, in which the uplink TTI length and the downlink TTI length may be different. The downlink TTI length may be a shortened TTI (sTTI) length, and the uplink TTI length may be longer than the downlink sTTI length. Various parameters for transmissions may be determined based on one or more of the uplink TTI length or the downlink TTI length, such as one or more of a feedback process transmission timing, a timing advance (TA) value, a transport block size (TBS), a number of spatial layers, a number of component carriers (CCs), or a channel quality information (CQI) reporting type may be determined based on one or more of the uplink TTI length or the downlink TTI length.

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 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: 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: Techniques are described for wireless communication. A first method includes winning a contention for access to an unlicensed radio frequency spectrum band, and transmitting at least a portion of a channel usage beacon signal (CUBS) over the unlicensed radio frequency spectrum band. The at least portion of the CUBS is transmitted in a number of frequency interlaces of the unlicensed radio frequency spectrum band. A second method includes winning a contention for access to an unlicensed radio frequency spectrum band; determining whether the contention is won within a threshold time before a next symbol period boundary; and transmitting at least a portion of a CUBS over the unlicensed radio frequency spectrum band. The at least portion of the CUBS is transmitted during a preamble including a fractional period of a first symbol period. The at least portion of the CUBS may be based at least in part on the determining.

Abstract: Techniques are described for wireless communication. In one method, a positioning reference signal (PRS) may be generated. The PRS may be configured in at least one downlink subframe among a plurality of downlink subframes. The PRS may be transmitted in the at least one downlink subframe using an unlicensed radio frequency spectrum band.

Abstract: Methods, systems, and devices for wireless communication are described. A base station may indicate time and frequency resources for a low latency physical downlink control channel (sPDCCH), which may be different from another physical downlink control channel (PDCCH), to a user equipment (UE). The base station may then transmit a common sPDCCH (CsPDCCH) message to indicate which low latency control channel elements (sCCEs) are used for sPDCCH transmission during a given subframe. In some cases, the signaling used to indicate the initial resource allocation for sPDCCH may be infrequent relative to the CsPDCCH transmissions. If some of the resources initially allocated for sPDCCH are not actually used for sPDCCH during a subframe, the base station and the UE may use those resources for communicating data. For example, the base station may transmit data using a low latency physical downlink shared channel (sPDSCH) to the UE using those resources.

Abstract: Aspects of the present disclosure relate to wireless communications and, more particularly, to synchronization for standalone long term evolution (LTE) broadcast. In one aspect, a method is provided which may be performed by a wireless device such as a base station (BS). The method generally includes providing unicast coverage to one or more user equipments (UEs) in a unicast coverage area within a larger coverage area, transmitting unicast data in one or more subframes, and transmitting synchronization signals within one or more of the broadcast subframes, wherein the broadcast signals are transmitted as single frequency network (SFN) transmissions synchronized with transmissions from one or more other base stations providing unicast coverage within the larger coverage area.

Abstract: Wireless communication methods, systems, and devices capable of utilizing base graphs for error correction techniques. A base graph can be used to derive a low-density parity-check (LDPC) code used for encoding a retransmission of an original transmission in a wireless communication system. An exemplary method generally includes selecting, based on a modulation and coding scheme (MCS) and a resource allocation (RA) for transmitting a codeword, a base graph (BG), from which to derive a low density parity check (LDPC) code for use in encoding data bits in the codeword (e.g., encoding data bits of a bitstream such that some redundant bits are included in the codeword), encoding the data bits to generate the codeword using the LDPC code derived from the selected BG, and transmitting the codeword using the MCS via resources of the RA.

Abstract: Methods, systems, and devices for wireless communication are described. Different transmission time interval (TTI) durations may be supported and configured to coexist with one another. A set of TTIs with a relatively short duration may overlap in time with longer duration TTIs. Boundaries of TTIs with a relatively short duration may be configured to align with boundaries of relatively longer duration TTIs. For example, TTIs that are a Long Term Evolution (LTE) subframe, an LTE slot, and a duration of two LTE symbol periods may be supported. Two-symbol period TTIs may align with or be embedded within slot-duration TTIs, which, in turn, may align with or be embedded within a subframe. In some examples, one or more symbol periods of a subframe may be designated as a gap between two-symbol TTIs within the subframe, or such symbols may be merged with a two-symbol TTI within the subframe.

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: 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.