Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive an indication of an interference threshold for interference caused by beamforming at the UE. The UE may transmit a signal using a beam with an interference value that satisfies the interference threshold. Numerous other aspects are described.

Abstract: The present disclosure relates to dynamic antenna array reconfiguration and signaling in millimeter wave bands. A user equipment (UE) may detect an antenna array change condition. The UE may transmit a request for beam training for an antenna array configuration in response to the detecting. The request for beam training may include a requested antenna array configuration for the UE and an indication of beam weights to use with the requested antenna array configuration. A base station may determine whether to grant or deny the requested antenna array configuration for the UE. The UE may receive, from the base station, an indication of an antenna array configuration for the UE. The base station may transmit the number of reference signals as a set of contiguous channel state information reference signals (CSI-RS). The UE may train the reconfigured active antenna array configuration based on the reference signals.

Abstract: A first wireless device and a second device may negotiate a configuration of an RF chain calibration process with each other. The configuration of the RF chain calibration process may include a number of calibration rounds. The second wireless device may exchange, in each calibration round in the number of calibration rounds, at least one RS and at least one feedback message with the first wireless device. The second wireless device may identify one or more calibration adjustment parameters for the second wireless device based on the RF chain calibration process. The second wireless device may communicate with another wireless device based on the one or more calibration adjustment parameters.

Abstract: Method and apparatus for two-way beamforming operations for calibration. The apparatus receives a first set of reference signals from a network node using N sets of beam weights over N symbols. The apparatus estimates a complex-valued beamformed channel based on the first set of reference signals. The apparatus transmits a second set of reference signals to the network entity using the N sets of beam weights. The apparatus receives a set of feedback signals from the network entity comprising measurements of the transmitted second set of reference signals. The apparatus computes a set of calibration adjustment factors between transmit and receive parts of a set of beam weights based on the set of feedback signals and the estimated complex-valued beamformed channel. The apparatus performs a calibration adjustment operation based on the computed set of calibrated adjustment factors.

Abstract: Aspects are provided which allow AGC symbols to be applied for identifying or indicating target Rx UEs of sidelink communications from Tx UEs. A Tx UE transmits an AGC signal to a Rx UE in a RB associated with the Rx UE. The Rx UE receives the AGC signal from the Tx UE. The Tx UE transmits sidelink data to the Rx UE after the AGC signal. The Rx UE decodes sidelink data from the Tx UE in response to the AGC signal being received in a RB associated with the Rx UE. The Rx UE refrains from decoding the sidelink data from the Tx UE in response to the AGC signal being received in a different RB than the RB associated with the Rx UE. In this way, Rx UEs may save monitoring and processing power and time in receiving and decoding sidelink communications.

Abstract: Methods, systems, and devices for wireless communications are described that support beam correlation across frequency bands for beam selection in the event of a frequency switch. For example, a base station may determine a configuration indicating a mapping between a set of beam identifiers (IDs) and a set of angle coverage ranges for a set of frequency ranges which corresponds to a user equipment's (UE) operating frequencies. In some examples, the UE may undergo a frequency switch and switch from a first operating frequency to a second operating frequency. The UE may select a beam ID based on the mapping and communicate with the base station via the second operating frequency using a beam associated with the selected beam ID.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first network node may receive, from a second network node, a first set of reference signals, wherein receiving the first set of reference signals comprises receiving each reference signal using a respective antenna element of the first network node. The first network node may transmit, to the second network node, a second set of reference signals, wherein the second set of reference signals is based on the first set of reference signals, and wherein each reference signal of the second set of reference signals is associated with an antenna element of the plurality of antenna elements of the first network node. The first network node may receive, from the second network node, an estimation report comprising estimation information associated with the second set of reference signals. Numerous other aspects are described.

Abstract: Certain aspects of the present disclosure provide techniques for wireless communications by a user equipment (UE) includes transmitting, in a first symbol in time of a slot, an automatic gain control (AGC) signal, wherein the UE transmits the AGC signal at a first power over a first frequency bandwidth; and transmitting, in a plurality of symbols of a mini-slot of the slot, a second AGC signal and data, wherein the UE refrains from transmitting between the first symbol and the plurality of symbols.

Abstract: Certain aspects of the present disclosure provide techniques for configuring sidelink slots with multiple automatic gain control symbols. One aspect provides a method for wireless communication by a user equipment, including enabling a slot configuration comprising at least two symbols configured for use by a receiver for automatic gain control in preconfigured symbol locations within a slot, and transmitting the at least two symbols while transmitting symbols within the slot.

Abstract: Certain aspects of the present disclosure provide techniques for configuring sidelink slots without symbols for automatic gain control. One aspect provides a method for wireless communication by a user equipment, including receiving a first cyclic prefix of a first symbol within a slot at the user equipment. The method further includes configuring a first automatic gain control setting based on a received power in the first cyclic prefix of the first symbol, and receiving a data portion of the first symbol using the first automatic gain control setting.

Abstract: Aspects described herein relate to receiving, from a device, a first reference signal transmitted using a first set of antenna elements over a first polarization, receiving, from the device, a second reference signal transmitted using a second set of antenna elements over a second polarization, determining, based on the first reference signal and the second reference signal, an inter-polarization phase adjustment to be applied to signals transmitted from the first set of antenna elements or the second set of antenna elements, and transmitting, to the device, an indication of the inter-polarization phase adjustment.

Abstract: Aspects described herein relate to determining a condition related to at least one of a thermal condition at the first device or receiving, at the first device, rate or diversity parameters reported to the first device by a second device, modifying, based on determining the condition, a configuration of a set of antenna elements from at least one antenna panel to use in wireless communication, and communicating with one or more devices using the modified configuration of the set of antenna elements from the at least one antenna panel.

Abstract: Methods, systems, and devices for wireless communications are described. A codebook adaptation may be performed for a flexible user equipment (UEs) to determine a codebook for a physical configuration of the UE. For example, if the UE determines that the physical configuration does not correspond to a pre-loaded codebook in its memory, the UE may provide information about the physical configuration to a base station to determine a corresponding codebook. Additionally, the UE may request that the base station provide channel information to assist with the codebook determination. In some cases, this request may indicate for the base station to allocate a specific number of channel state information reference signal symbols that the UE can use for the codebook determination. Additionally or alternatively, the UE may generate the codebook internally and then signal to the base station a request for a beam refinement procedure with the generated codebook.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit, and a base station may receive, information related to multipath richness of a channel environment and information related to antenna module capabilities associated with the UE for at least a first frequency band and a second frequency band. The base station may transmit, and the UE may receive, information indicating a multiple input multiple output (MIMO) mode in which to operate one or more antenna modules of the UE based at least in part on the information related to the multipath richness of the channel environment, the antenna module capabilities associated with the UE, and respective cell loadings in the first frequency band and the second frequency band. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit, to a base station such as a eNodeB (eNB), a next-generation NodeB or giga-NodeB (either of which may be referred to as a gNB)), an indication of a value of a channel quality parameter of a wireless link including a first beam pair between the UE and the base station. The UE may also transmit, to the base station, side information different from and in addition to the indication of the value of the channel quality information, and receive, in response to the transmitted indication of the value and the transmitted side information, an indication of resources for the UE to use to communicate on the wireless link.

Abstract: Methods, systems, and devices for wireless communications are described. A codebook adaptation may be performed for a flexible user equipment (UEs) to determine a codebook for a physical configuration of the UE. For example, if the UE determines that the physical configuration does not correspond to a pre-loaded codebook in its memory, the UE may provide information about the physical configuration to a base station to determine a corresponding codebook. Additionally, the UE may request that the base station provide channel information to assist with the codebook determination. In some cases, this request may indicate for the base station to allocate a specific number of channel state information reference signal symbols that the UE can use for the codebook determination. Additionally or alternatively, the UE may generate the codebook internally and then signal to the base station a request for a beam refinement procedure with the generated codebook.

Abstract: Aspects described herein relate to receiving, from a device, a first reference signal transmitted using a first set of antenna elements over a first polarization, receiving, from the device, a second reference signal transmitted using a second set of antenna elements over a second polarization, determining, based on the first reference signal and the second reference signal, an inter-polarization phase adjustment to be applied to signals transmitted from the first set of antenna elements or the second set of antenna elements, and transmitting, to the device, an indication of the inter-polarization phase adjustment.

Abstract: Aspects described herein relate to determining a condition related to at least one of a thermal condition at the first device or receiving, at the first device, rate or diversity parameters reported to the first device by a second device, modifying, based on determining the condition, a configuration of a set of antenna elements from at least one antenna panel to use in wireless communication, and communicating with one or more devices using the modified configuration of the set of antenna elements from the at least one antenna panel.

Abstract: Methods, systems, and devices for wireless communications are described. One method may inlcude a base station or other device estimating an intended coverage area of all possible communication devices that are to be serviced by the base station or other device. The base station or other device may dynamically optimize at least one transmission metric such as a codebook, in response to a change in the coverage area. Another method may include a base station estimating a dynamic coverage area of a set of all possible user equipments or devices to be serviced, and dynamically optimizing a codebook structure in response to a change in the coverage area. Another method may include the base station determining a use-case of the set of all possible user equipments to be serviced by the base station, and hard-coding a metric corresponding to the use case.

Abstract: Methods, systems, and devices for wireless communications are described that support beam correlation across frequency bands for beam selection in the event of a frequency switch. For example, a base station may determine a configuration indicating a mapping between a set of beam identifiers (IDs) and a set of angle coverage ranges for a set of frequency ranges which corresponds to a user equipment's (UE) operating frequencies. In some examples, the UE may undergo a frequency switch and switch from a first operating frequency to a second operating frequency. The UE may select a beam ID based on the mapping and communicate with the base station via the second operating frequency using a beam associated with the selected beam ID.