Abstract: This disclosure provides systems, methods and apparatus for wireless communications that support fallback from a 2-step to a 4-step random access procedures. A user equipment (UE) may establish a connection with a base station using a random access procedure. The random access procedure may be a 2-step random access procedure and reduce a number of handover exchange messages. The 2-step random access procedure may include the UE transmitting, to the base station, a first random access message including a preamble and a payload. In some implementations, the base station may receive the preamble but fail to receive or decode the payload. The random access procedure may utilize the received preamble information instead of performing retransmission of the first random access message. The base station may transmit a second random access message to the UE indicating, explicitly or implicitly, a fallback to a 4-step random access procedure for connection establishment.

Abstract: Aspects are provided allowing a UE to transmit repetitions of an ULT, PEI-R, or other uplink reference signal for on-demand SSB, RMSI, or paging transmissions. A base station initially transmits an indication of a configured uplink repetition mode, which may comprise a first, second, or third mode in which a one-to-one, one-to-many, or many-to-many mapping exists between downlink reference signals and uplink occasions, respectively. Afterwards, the UE receives downlink reference signals via different transmission beams of the base station. In response to the downlink reference signals, the UE transmits an uplink reference signal repetition in one or more uplink occasions associated with one or more of the downlink reference signals according to the configured uplink repetition mode. In response to the uplink reference signal repetition, the base station may transmit a SSB, RMSI, or paging message. Thus, a balance between network energy savings and uplink signal reliability may be achieved.

Abstract: Techniques are described herein for periodically transmitting a first set of signals (e.g., reference signals) during an on-period of a discontinuous reception (DRX) cycle rather than during an off-period of the DRX cycle. Such techniques may enable a user equipment (UE) operating in a DRX mode to conserve additional power during the DRX cycle. A periodicity for transmitting the first set of signals during the on-period may be determined. The periodicity may indicate that every one-in-N DRX cycles, the first set of signals are to be transmitted during the on-period. During other DRX cycles, the first set of signals may be transmitted during the off-period. When the first set of signals are transmitted during the on-period, the UE may refrain from activating certain components during the off-period, thereby conserving power.

Abstract: The present disclosure relates to methods and devices for wireless communication at a wireless device or integrated access and backhaul (IAB) node. In one aspect, the wireless device may determine a frequency synchronization accuracy for the wireless device. The wireless device may also transmit an indication of the determined frequency synchronization accuracy for the wireless device. Additionally, the wireless device may determine an absolute frequency based on a combination of measurements from at least one synchronization source and a frequency of the wireless device, where the frequency synchronization accuracy is based on the absolute frequency.

Abstract: Techniques are described for wireless communication. In one method, a user equipment (UE) receives a timing synchronization signal (TSS) and a physical broadcast channel (PBCH), with the TSS based at least in part on a timing of the TSS within a broadcast channel transmission time interval (BCH TTI); determines the timing of the TSS within the BCH TTI; and demodulates the PBCH based at least in part on the TSS. In another method, a base station allocates resources for a TSS and a PBCH within a BCH TTI; determines the TSS based at least in part on a timing of the TSS within the BCH TTI; and transmits, on the resources allocated for the TSS and the PBCH, the TSS and the PBCH, with the TSS transmitted as a demodulation reference signal (DMRS) for the PBCH on at least one port used to transmit the TSS and the PBCH.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first network entity may receive, from a second network entity, configuration information indicating multiple physical random access channel (PRACH) preamble configurations that are associated with respective cyclic shifts. The first network entity may transmit, to the second network entity, a random access communication that includes a PRACH preamble in accordance with a PRACH preamble configuration of the multiple PRACH preamble configurations, the PRACH preamble configuration being selected based on timing information of the first network entity. Numerous other aspects are described.

Abstract: Wireless communications systems and methods related to the timing arrangements and the transmission gap configurations in 2-step random access channel (RACH) procedures to improve system latency and reliability of a RACH HARQ process are provided. The UE transmits a first message including a random access preamble and a payload, and then monitors for a second message in response to the first message during a random access response (RAR) window. In response to determining that no second message is received by the UE from the BS or a back off indicator is received within the RAR window, the UE re-transmits the preamble and payload of the first message after the RAR window lapses. In response to determining if the second message received within the RAR window carries a FallbackRAR or SuccessRAR, the UE then determines to re-transmit the payload of the first message based on the FallbackRAR, or to transmit an acknowledgement message based on the SuccessRAR.

Abstract: A method includes retrieving a plurality of images containing one or more objects of interest and generating, with one or more processors, using a machine learning model, a bounding box around each of the one or more objects of interest for each of the plurality of images. The method also includes determining, with the one or more processors, a geographical position of each of the one or more objects of interest based on a position of the bounding box.

Abstract: Aspects described herein relate to configuring a device to skip multiple paging early indication (PEI) occasions. An indication of a skip duration of multiple discontinuous receive (DRX) cycles to skip in monitoring for a paging early indication (PEI) can be received, and a reduced power state can be entered for the skip duration. After the skip duration, an increased power state can be entered to monitor for the PEI, a synchronization signal block (SSB), or one or more reference signals.

Abstract: Methods, systems, and devices for wireless communications are described that provide for hop-count indication in an integrated access and backhaul (IAB) network. An IAB-node may adopt and indicate multiple values for hop-count. The hop-count may be conveyed by a number of different reference signals and channels. A resource pattern and/or a slot pattern may also be associated with the hop-count to simply signaling. By associating the patterns with the hop-count, an IAB-node may be able to infer the resource pattern used by another IAB-node.

Abstract: Methods, systems, and devices for wireless communication are described. In some wireless systems, a user equipment (UE) may access a network or cell using a random access (RACH) procedure. A base station may allocate dedicated RACH resources and common RACH resources for the UE to transmit a RACH preamble message on and may convey a configuration for the UE. In some cases, the UE may perform multiple transmissions of the RACH preamble message in the dedicated RACH resources, and based on the configuration may determine whether to perform a single or multiple transmissions of the RACH preamble message in the common RACH resources. The UE may transmit the messages using the same or different uplink transmit beams, and the base station may receive the messages using the same or different uplink reception beams. These multiple transmissions may reduce latency and improve reliability of the RACH procedure.

Abstract: The present disclosure relates to wireless communication in mmW networks. The apparatus may be a base station. The apparatus may be configured to determine a first symbol index and a second symbol index associated with downlink resources allocated to a UE. The first symbol index may indicate when the downlink resources begin in a subframe, and the second symbol index may indicate when the downlink resources end in the subframe. The apparatus may be configured to transmit an indication of the first symbol index and the second symbol index to the UE.

Abstract: Methods, systems, and devices for wireless communication are described. The methods, systems, and devices provide for identifying tone spacing for transmission or reception of signals. The identified tone spacing may vary depending on the transmission or reception spectrum band or signal type. Using the identified tone spacing, a number of repetitions or a number of symbols for transmission or receiver algorithm of a signal may be determined.

Abstract: Aspects relate to random access channel procedures. In some examples, if a user equipment (UE) has not successfully received a random access channel (RACH) downlink message prior to the end of a random access window for a first RACH attempt, the UE may elect to proceed with a second RACH attempt. For example, the UE may determine whether there are any remaining downlink symbols available during the random access window to receive the RACH downlink message. If not, the UE may retransmit a physical RACH (PRACH) preamble.

Abstract: Methods, systems, and devices for wireless communication are described. A base station may identify that data is available to be transmitted to a user equipment (UE) that is operating in a discontinuous reception (DRX) mode. The base station may transmit, based at least in part on the data being available, a first wakeup message using a first band supported by the UE. The base station may transmit, based at least in part on the data being available, a second wakeup message using a second band supported by the UE, the second band being different from the first band.

Abstract: Aspects of the present disclosure provide techniques for beam and cell selection based on power configuration of a wireless node (e.g., an Integrated Access and Backhaul (IAB) node). In some cases, the node monitors synchronization signal block (SSB) transmissions from one or more network entities, and selects a beam or cell based on the monitoring and one or more metrics designed to limit potential interference caused by uplink transmissions from the first node.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a base station (BS) may group and selectively multiplex a plurality of random access channel responses (RARs) and radio resource control (RRC) messages in a message B (msgB) communication, together with supplementary scheduling information for other RARs to be mapped to a different msgB communication. The BS may transmit the msgB communication to one or more user equipments. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communication are described. A base station may transmit a paging indicator message to one or more user equipment (UEs) in a group of UEs. The base station may receive, based at least in part on the paging indicator message, a first response message from the one or more UEs. The first response message may be received using a resource that is shared with a random access channel message for the group of UEs. The base station may transmit, based at least in part on the first response message, a second response message to the one or more UEs.

Abstract: Techniques are described for wireless communication. In one method, a user equipment (UE) receives a timing synchronization signal (TSS) and a physical broadcast channel (PBCH), with the TSS based at least in part on a timing of the TSS within a broadcast channel transmission time interval (BCH TTI); determines the timing of the TSS within the BCH TTI; and demodulates the PBCH based at least in part on the TSS. In another method, a base station allocates resources for a TSS and a PBCH within a BCH TTI; determines the TSS based at least in part on a timing of the TSS within the BCH TTI; and transmits, on the resources allocated for the TSS and the PBCH, the TSS and the PBCH, with the TSS transmitted as a demodulation reference signal (DMRS) for the PBCH on at least one port used to transmit the TSS and the PBCH.

Abstract: Methods, systems, and devices for wireless communication are described. A network device, such as a base station, may transmit a request message to a user equipment (UE). The request message may include a request for the UE to transmit a set of sounding reference signals (SRSs). The set of SRSs may include two (or more) beamformed signals. The network device may receive the set of SRSs according to the request message. The network device may identify, based on a co-phasing parameter associated with the two (or more) beamformed signals, an antenna port precoder configuration to use for communicating with the UE.