Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may select one or more sub-bands, of a plurality of sub-bands in a wideband structure of an unlicensed spectrum, for processing in association with receiving a reference signal. The one or more sub-bands may include at least one valid sub-band of a set of valid sub-bands in which the reference signal is received. The user equipment may process the one or more sub-bands in association with receiving the reference signal. Numerous other aspects are provided.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may detect that at least a portion of reference signaling expected in a channel is not present in the channel. The UE may modify a Doppler estimation computation associated with the reference signaling based at least in part on detecting that at least the portion of the reference signaling is not present in the channel. Numerous other aspects are described.

Abstract: Methods, systems, and devices for dynamic monitoring modes for synchronization signal block (SSB) transmissions are described. A user equipment (UE) may monitor one or more first SSB transmission opportunities for SSB transmissions from a base station and determine an SSB failure rate. Based on the failure rate, the UE may select a mode for monitoring one or more second SSB transmission opportunities. For example, if the failure rate is greater than a threshold, the UE may select a first mode for monitoring a first quantity of the one or more second SSB transmission opportunities. Additionally, if the failure rate is less than the threshold, the UE may select a second mode for monitoring a second quantity different than the first quantity of the one or more second SSB transmission opportunities. The UE may monitor the one or more second SSB transmission opportunities according to the selected mode for monitoring.

Abstract: Methods, systems, and devices for wireless communications are described. The described techniques provide for dynamic updates to beam failure detection (BFD) reference signals (RSs) and path loss RS using medium access control-control element (MAC-CE) or downlink control information (DCI). For example, the quasi co-location (QCL) of periodic CSI-RS may be dynamically updated by the MAC-CE or DCI when the periodic CSI-RS is for BFD RS. Also, a semi-persistent CSI-RS or aperiodic CSI-RS may act as a BFD RS. An enhanced update procedure may be used to update the path loss RS dynamically using MAC-CE or DCI. In some cases, the path loss RS parameters updated via MAC-CE or DCI may overwrite the previously RRC configured path loss RS parameters. In another example, if the path loss RS is not configured, then the path loss RS by default may be the spatial relation reference signal of the corresponding uplink beam.

Abstract: Methods, systems, and devices for wireless communications are described. The described techniques provide for dynamic updates to beam failure detection (BFD) reference signals (RSs) and path loss RS using medium access control-control element (MAC-CE) or downlink control information (DCI). For example, the quasi co-location (QCL) of periodic CSI-RS may be dynamically updated by the MAC-CE or DCI when the periodic CSI-RS is for BFD RS. Also, a semi-persistent CSI-RS or aperiodic CSI-RS may act as a BFD RS. An enhanced update procedure may be used to update the path loss RS dynamically using MAC-CE or DCI. In some cases, the path loss RS parameters updated via MAC-CE or DCI may overwrite the previously RRC configured path loss RS parameters. In another example, if the path loss RS is not configured, then the path loss RS by default may be the spatial relation reference signal of the corresponding uplink beam.

Abstract: This disclosure relates to random access channel (RACH) enhancements for new radio unlicensed (NR-U) communications. Specifically, the present aspects include determining whether a gap length between a two-step random access channel (RACH) preamble transmission and a physical uplink shared channel (PUSCH) transmission satisfies a gap condition. The present aspects further include selecting a transmission procedure associated with the determined gap length for the PUSCH transmission. The present aspects further include performing the PUSCH transmission in accordance with the selected transmission procedure.

Abstract: A random access channel (RACH) procedure allows a user equipment (UE) to achieve synchronization with a network and obtain network resources and services from a scheduling entity. This disclosure provides various options for implementing a two-step RACH procedure that can support various UE behaviors in relation to using or not using a time symbol gap between a physical random access channel (PRACH) resource and a physical uplink control channel (PUCCH) resource.

Abstract: Methods, systems, and devices for wireless communications are described. A base station may identify an active transmission configuration indicator (TCI) state, a set of active TCI states, and/or a spatial relation reference signal identifier to be used for one or more component carriers (CCs) of a UE. The base station may then transmit a control message to the UE that may indicate the identified active TCI state, set of active TCI states, and/or spatial relation reference signal identifier to be used for one or more CCs and/or bandwidth parts of the UE. The UE may determine a communication configuration for a CC of the plurality of CC based on the control message and an optional shared command indication. The UE may the apply the TCI state or set of active TCI states to a subset of CCs, or UE may configure sounding reference signals for a subset of CCs.

Abstract: Methods, systems, and devices for wireless communications are described. The described techniques provide for dynamic updates to beam failure detection (BFD) reference signals (RSs) and path loss RS using medium access control-control element (MAC-CE) or downlink control information (DCI). For example, the quasi co-location (QCL) of periodic CSI-RS may be dynamically updated by the MAC-CE or DCI when the periodic CSI-RS is for BFD RS. Also, a semi-persistent CSI-RS or aperiodic CSI-RS may act as a BFD RS. An enhanced update procedure may be used to update the path loss RS dynamically using MAC-CE or DCI. In some cases, the path loss RS parameters updated via MAC-CE or DCI may overwrite the previously RRC configured path loss RS parameters. In another example, if the path loss RS is not configured, then the path loss RS by default may be the spatial relation reference signal of the corresponding uplink beam.

Abstract: Techniques for wireless communications are described. A user equipment (UE) may initially configure a set of channel estimation parameters for a set of radio frequency spectrum subbands of a bandwidth part (BWP) of a transmission opportunity (TxOP). In some examples, the UE may identify an unavailable radio frequency spectrum subband within the BWP. Based on the identification, the UE may reconfigure the channel estimation parameters to avoid performing unnecessary channel estimation processes on the unavailable radio frequency spectrum subband. As part of reconfiguring the channel estimation parameters, the UE may set log-likelihood ratio (LLR) values of subcarriers associated with the unavailable radio frequency spectrum subband to a null value, thereby experiencing improvements in efficiency and reliability of channel estimation for the BWP.

Abstract: A configuration to improve the manner in which a UE is configured to perform RLM for UEs that do not support CSI-RS based RLM. The apparatus may transmit, to a base station, an indication including a RLM capability. The apparatus may receive, from the base station, a RLM RS configuration from the UE based on the indication. The apparatus determines the RLM RS configuration for the UE, based on the RLM RS configuration received from the base station.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may detect whether a reference signal is present in a channel at a time instance at which the reference signal is expected. The UE may selectively gate processing of the reference signal based on detecting whether the reference signal is present in the channel. Numerous other aspects are described.

Abstract: A random access channel (RACH) procedure allows a user equipment (UE) to achieve synchronization with a network and obtain network resources and services from a scheduling entity. This disclosure provides various options for implementing a two-step RACH procedure that can support various UE behaviors in relation to using or not using a time symbol gap between a physical random access channel (PRACH) resource and a physical uplink control channel (PUCCH) resource.

Abstract: Methods, systems, and devices for dynamic monitoring modes for synchronization signal block (SSB) transmissions are described. A user equipment (UE) may monitor one or more first SSB transmission opportunities for SSB transmissions from a base station and determine an SSB failure rate. Based on the failure rate, the UE may select a mode for monitoring one or more second SSB transmission opportunities. For example, if the failure rate is greater than a threshold, the UE may select a first mode for monitoring a first quantity of the one or more second SSB transmission opportunities. Additionally, if the failure rate is less than the threshold, the UE may select a second mode for monitoring a second quantity different than the first quantity of the one or more second SSB transmission opportunities. The UE may monitor the one or more second SSB transmission opportunities according to the selected mode for monitoring.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive configurations for a plurality of search space sets for a control resource set (CORESET), the plurality of search space sets including one or more of a first type of search space set configured with multiple frequency domain monitoring locations or a second type of search space set configured without multiple frequency domain monitoring locations. The UE may receive a physical downlink control channel communication based at least in part on monitoring the plurality of search space sets according to a determination that the CORESET is associated with search space sets of a same type. Numerous other aspects are described.

Abstract: This disclosure relates to random access channel (RACH) enhancements for new radio unlicensed (NR-U) communications. Specifically, the present aspects include determining whether a gap length between a two-step random access channel (RACH) preamble transmission and a physical uplink shared channel (PUSCH) transmission satisfies a gap condition. The present aspects further include selecting a transmission procedure associated with the determined gap length for the PUSCH transmission. The present aspects further include performing the PUSCH transmission in accordance with the selected transmission procedure.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may select one or more sub-bands, of a plurality of sub-bands in a wideband structure of an unlicensed spectrum, for processing in association with receiving a reference signal. The one or more sub-bands may include at least one valid sub-band of a set of valid sub-bands in which the reference signal is received. The user equipment may process the one or more sub-bands in association with receiving the reference signal. Numerous other aspects are provided.

Abstract: Techniques for wireless communications are described. A user equipment (UE) may initially configure a set of channel estimation parameters for a set of radio frequency spectrum subbands of a bandwidth part (BWP) of a transmission opportunity (TxOP). In some examples, the UE may identify an unavailable radio frequency spectrum subband within the BWP. Based on the identification, the UE may reconfigure the channel estimation parameters to avoid performing unnecessary channel estimation processes on the unavailable radio frequency spectrum subband. As part of reconfiguring the channel estimation parameters, the UE may set log-likelihood ratio (LLR) values of subcarriers associated with the unavailable radio frequency spectrum subband to a null value, thereby experiencing improvements in efficiency and reliability of channel estimation for the BWP.

Abstract: Methods, systems, and devices for wireless communication are described. A user equipment (UE) may receive a first grant to perform a first uplink transmission in a first subframe using a first component carrier. The UE may receive a second grant to perform a second uplink transmission in a second subframe adjacent the first subframe in time. The UE may determine to null one or more symbols of the uplink transmission in the first subframe based at least in part on the second grant. In some cases, the UE may determine to null the one or more symbols of the first uplink transmission is based at least in part on an availability of a single radio frequency (RF) frontend for use by the UE.

Abstract: A configuration to improve the manner in which a UE is configured to perform RLM for UEs that do not support CSI-RS based RLM. The apparatus may transmit, to a base station, an indication including a RLM capability. The apparatus may receive, from the base station, a RLM RS configuration from the UE based on the indication. The apparatus determines the RLM RS configuration for the UE, based on the RLM RS configuration received from the base station.