Abstract: Methods, systems, and devices for wireless communications are described. A first device may include reflective elements and may reflect signals between a second and third device using the reflective elements. In some cases, the first device may receive signaling from the second device indicating a first subset of the reflective elements corresponding to a first phase configuration and a second subset of the reflective elements corresponding to a second phase configuration. In some other cases, the first device may receive signaling indicating a transmission beam of the second device. Here, the first device may identify the first and second subsets of the reflective elements based on an angle of arrival and departure associated with the indicated transmission beam. In either case, the first device may set the phase configurations of the reflective elements according to the first and second subsets.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a receiving user equipment (UE) may transmit a first measurement that is based at least in part on a first reference signal, from a base station, that is to be reflected via a passive device. The receiving UE may transmit a second measurement that is based at least in part on a second reference signal, from a transmitting UE, that is to be reflected via the passive device and a third reference signal from the transmitting UE. Numerous other aspects are described.

Abstract: Methods, systems, and devices for wireless communication are described. A first wireless communications device may receive, from a second wireless communications device, a signal that is indicative of a phase-change pattern applied to communications between the first wireless communications device and the second wireless communication device by a reconfigurable intelligent surface reflecting the communications. The first device may determine the phase-change pattern from the signal. The first device may transmit a message to the second wireless communications device, wherein at least one of a content or a transmission property of the message is based at least in part on the phase-change pattern.

Abstract: Methods, systems, and devices for wireless communications are described. The method includes receiving, from a network entity at a control unit associated with a reconfigurable intelligent surface, a set of multiple reference signals via a set of multiple receive beams, acquiring, via a first antenna panel associated with the control unit, a first beam of the set of multiple receive beams, acquiring, via a second antenna panel associated with the control unit, a second beam of the set of multiple receive beams, determining reflection coefficients of the reconfigurable intelligent surface for communication with the network entity based on the acquiring of the first beam and the acquiring of the second beam, and communicating via the reconfigurable intelligent surface based on the reflection coefficients of the reconfigurable intelligent surface.

Abstract: Methods, systems, and devices for wireless communications are described. The method includes a reconfigurable intelligent surface receiving, from a network entity, a synchronization signal block associated with a synchronization signal block index, reflecting the synchronization signal block as a set of multiple instances of the synchronization signal block via a corresponding set of multiple downlink transmit beams, receiving a random access message from a user equipment (UE) during a random access occasion that corresponds with the synchronization signal block index and on an uplink receive beam that corresponds with one of the set of multiple downlink transmit beams, identifying the phase-change pattern of multiple phase-change patterns that corresponds to the uplink receive beam, and reflecting the random access message to the network entity by applying the phase-change pattern to antenna elements of the reconfigurable intelligent surface that reflect the random access message to the network entity.

Abstract: Methods, systems, and devices for wireless communications are described. In some systems, a user equipment (UE) and a base station may participate in a one-shot initial access procedure involving a reconfigurable intelligent surface (RIS) divided into a number of sub-RISs, each sub-RIS associated with a different configuration for reflecting signaling from the base station. In some aspects, the base station may configure each sub-RIS to have a different frequency shift and transmit, to the UE, a parameter indicating a quantity of synchronization rasters associated with each of a set of beams that the base station may use as part of the one-shot initial access procedure. The UE may, for each beam, monitor a quantity of monitoring occasions corresponding to the quantity of synchronization rasters and transmit random access signaling to the base station based on which synchronization raster of which beam provides a greatest signal strength at the UE.

Abstract: Methods, systems, and devices for wireless communications are described. A example method for wireless communication at a reconfigurable reflective surface comprises receiving one or more signals from a first wireless device and determining, based at least in part on the one or more signals, measurement information pertaining to a wireless channel between the reconfigurable reflective surface and the first wireless device. The example method may further include determining, based at least in part on the measurement information, a set of weights for a plurality of reflective elements of the reconfigurable reflective surface to be used in reflecting communications between the first wireless device and a second wireless device.

Abstract: Methods, systems, and devices for wireless communications are described. In some systems, a base station may communicate with a user equipment (UE) via a reconfigurable intelligent surface (RIS) which is capable of adjusting a reflection characteristic to reflect incident signaling in different directions. The base station and the RIS may establish a beamformed connection and, in some scenarios, the base station and the RIS may experience a beam failure. In such scenarios, the base station, the UE, and the RIS may participate in a two-step beam training procedure to reduce an amount of possible beam pair hypotheses that the communicating devices test in order to re-establish communication between the base station and the UE via the RIS. The two-step beam training procedure may include a first procedure in which the RIS selects a suitable beam toward the base station and a second procedure that leverages the selected beam.

Abstract: Certain aspects of the present disclosure provide techniques for wireless communication by a network entity. For example, the network entity defines a size of reconfigurable intelligent surface (RIS) elements. The network entity further defines a set of patterns representing active RIS elements and/or inactive RIS elements, based on the size of RIS elements. The network entity transmits an indication of the size of RIS elements and the set of patterns to a RIS controller.

Abstract: A reconfigurable intelligent surface (RIS) may include multiple sub-RIS, and the base station may configure the RIS and the multiple sub-RIS with RIS sync raster including multiple center frequencies. The RIS may be configured to simultaneously apply different water-markings and reflect the incident beam into different beams in different directions. The base station may perform a beam-sweeping by transmitting synchronization signal blocks (SSBs) on multiple SSB beams, and the RIS may receive one SSB beam of the multiple SSB beams and reflect the SSB beams on the RIS sync raster. A UE may be configured to monitor the base sync raster and the RIS sync raster for a suitable SSB beam, and transmit a feedback report to the base station indicating the suitable beam. The base station may configure the RIS based on the feedback report received from the base station for beam management.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit an indication of a plurality of beams received by the UE. The UE may receive a message indicating at least a first resource set associated with one or more first beams from the plurality of beams and a second resource set associated with one or more second beams from the plurality of beams. The UE may transmit a report indicative of a level of correlation between pairs of individual beams, each pair including a first individual beam of the one or more first beams and a second individual beam of the one or more second beams, and the UE may communicate with the base station via a selected beam of the one or more first beams or the one or more second beams.

Abstract: Aspects of the present disclosure provide techniques for configuring RIS components in order to achieve a certain object. According to certain aspects, a first device may participate in a first training procedure to obtain a set of channel estimates corresponding to different paths between a second device and the first device involving reflections from different reconfigurable intelligent surface (RIS) components, participate in a second training procedure, using the set of channel estimates, to obtain a combining vector of coefficients to configure the RIS components based on at least one objective, and communicate with the second device with the RIS components configured according to the combining vector.

Abstract: A method for wireless communication performed by a user equipment (UE) includes receiving multiple reference signals (RSs), each RS of the plurality of RSs being associated with a reflection from a respective reconfigurable intelligent surface (RIS), of multiple RISs, or with a direct transmission from a base station. The method also includes receiving, from the base station, a RIS configuration indicating a set of operative RISs, of the plurality of RISs, that reflect an uplink transmission from the UE. The method further includes transmitting, to the base station, an uplink message according to an uplink transmission power, the uplink transmission power being based on an effective pathloss that is a function of each pathloss of a set of pathlosses respectively associated with a set of RSs, of the multiple RSs, that are respectively associated with the set of operative RISs or the base station.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may perform measurements of a first plurality of interference measurement resources on a channel from a reconfigurable intelligent surface (RIS) to the UE. The first plurality of interference measurement resources are associated with a plurality of beams. Accordingly, the UE may transmit a first report based at least in part on the measurements of the first plurality of interference measurement resources. The UE may additionally perform measurements of a second plurality of interference measurement resources on the channel from the RIS to the UE. The second plurality of interference measurement resources are associated with a plurality of phases. Accordingly, the UE may transmit a second report based at least in part on the measurements of the second plurality of interference measurement resources. Numerous other aspects are described.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive a configuration for a transmission configuration state for receiving downlink channel transmissions from a base station via a configurable surface. The transmission configuration state may indicate a quasi-co-location source associated with transmission via the configurable surface. The UE may receive a downlink channel transmission via the configurable surface based on the transmission configuration state and the quasi-co-location source. The UE may be capable of determining whether the transmission configuration state conflicts with the quasi-co-location source indicated by the transmission configuration state. The UE may transmit an indication to the base station that the configuration for the transmission configuration state conflicts with the quasi-co-location source. The indication may include a beam failure indication or a measurement report.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a first set of reference signals and a second set of reference signals from a base station, where the second set of reference signals are reflected from a first passive device operating as a reconfigurable intelligent surface (RIS). The UE may communicate with the base station in consideration of the first passive device. Numerous other aspects are described.

Abstract: A passive multiple-input multiple-output (P-MIMO) method that may be performed by a reconfigurable intelligent surface (RIS) includes applying a first voltage set to one or more unit cells of the RIS for reflecting a downlink signal from a first wireless communication device to a second wireless communication device. The method includes applying a second voltage set to the one or more unit cells of the RIS for reflecting an uplink signal from the second wireless communication device to the first wireless communication device.

Abstract: Schemes and mechanisms for timing advance adjustment are provided. In a method for wireless communication, a BS transmits, to a user equipment (UE), a first timing offset configuration associated with a first reconfigurable intelligent surface (RIS) state and a second timing offset configuration associated with a second RIS state. The BS transmits, to the UE, a timing offset indication indicating one of the first timing offset configuration or the second timing offset configuration. The BS receives, from the UE based on the timing offset indication, an uplink (UL) communication.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive configuration information identifying a set of sub-bands for receiving, via a set of reconfigurable intelligent surfaces (RISs), a signal. The UE may receive, via a first RIS of the set of RISs, the signal in a first sub-band of the set of sub-bands. The UE may receive, via a second RIS of the set of RISs, the signal in a second sub-band of the set of sub-bands. The UE may transmit, based at least in part on receiving the signal, RIS information indicating at least one of: first RIS information regarding the first RIS, or second RIS information regarding the second RIS. Numerous other aspects are described.

Abstract: Techniques for peak-to-average power ratio (PAPR) reduction are described. Wireless devices may provide signaling with respect to one or more PAPR shaping resources. For example, a wireless device may provide signaling of PAPR shaping capability information. PAPR shaping capability information may include information regarding one or more PAPR shaping resources the wireless device has a capability to implement. Additionally or alternatively, a wireless device may provide signaling of PAPR shaping information. PAPR shaping information may include information regarding shaping the signal by a wireless device prior to transmission in a communication link by implementing one or more PAPR shaping resources. Other aspects and features are also claimed and described.