Beam direction selection for transmission and reception in full duplex operation

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first wireless communication device (WCD) may transmit, to a second WCD, information for selecting transmission or reception directions for a first beam and a second beam for communications between the first WCD and the second WCD using a full duplex operation. The WCD may receive an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications. Numerous other aspects are provided.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for beam direction selection for transmission and reception in full duplex operation.

BACKGROUND

SUMMARY

In some aspects, a method of wireless communication performed by a first wireless communication device (WCD) includes: transmitting, to a second WCD, information for selecting transmission or reception directions for a first beam and a second beam for communications between the first WCD and the second WCD using a full duplex operation; and receiving an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications.

In some aspects, a method of wireless communication performed by a second WCD includes: determining, based at least in part on one or more of a scheduling constraint or a receipt of information for selecting transmission or reception directions, transmission or reception directions for a first beam and a second beam for communications between the second WCD and a first WCD using a full duplex operation; and transmitting, to the first WCD, an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications.

In some aspects, a first WCD for wireless communication includes: a memory; and one or more processors coupled to the memory, the memory and the one or more processors configured to: transmit, to a second WCD, information for selecting transmission or reception directions for a first beam and a second beam for communications between the first WCD and the second WCD using a full duplex operation; and receive an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications.

In some aspects, a second WCD for wireless communication includes: a memory; and one or more processors coupled to the memory, the memory and the one or more processors configured to: determine, based at least in part on one or more of a scheduling constraint or a receipt of information for selecting transmission or reception directions, transmission or reception directions for a first beam and a second beam for communications between the second WCD and a first WCD using a full duplex operation; and transmit, to the first WCD, an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications.

In some aspects, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes: one or more instructions that, when executed by one or more processors of a first WCD, cause the first WCD to: transmit, to a second WCD, information for selecting transmission or reception directions for a first beam and a second beam for communications between the first WCD and the second WCD using a full duplex operation; and receive an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications.

In some aspects, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes: one or more instructions that, when executed by one or more processors of a second WCD, cause the second WCD to: determine, based at least in part on one or more of a scheduling constraint or a receipt of information for selecting transmission or reception directions, transmission or reception directions for a first beam and a second beam for communications between the second WCD and a first WCD using a full duplex operation; and transmit, to the first WCD, an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications.

In some aspects, an apparatus for wireless communication includes: means for transmitting, to a WCD, information for selecting transmission or reception directions for a first beam and a second beam for communications between the apparatus and the WCD using a full duplex operation; and means for receiving an indication to use, for the full duplex operation of the apparatus, the first beam to receive communications and the second beam to transmit communications.

In some aspects, an apparatus for wireless communication includes: means for determining, based at least in part on one or more of a scheduling constraint or a receipt of information for selecting transmission or reception directions, transmission or reception directions for a first beam and a second beam for communications between the apparatus and a first WCD using a full duplex operation; and means for transmitting, to the first WCD, an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications.

DETAILED DESCRIPTION

In some aspects, a wireless communication device (e.g., UE120, an integrated access and backhaul (IAB) node, and/or the like) may include means for transmitting, to a second WCD, information for selecting transmission or reception directions for a first beam and a second beam (e.g., previously selected) for communications between the first WCD and the second WCD using a full duplex operation; means for receiving an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications; and/or the like. In some aspects, such means may include one or more components of UE120described in connection withFIG.2, such as controller/processor280, transmit processor264, TX MIMO processor266, MOD254, antenna252, DEMOD254, MIMO detector256, receive processor258, and/or the like.

In some aspects, a wireless communication device (e.g., base station110, an IAB node, a parent node, a distributed unit, a central unit, and/or the like in an IAB network) may include means for determining, based at least in part on one or more of a scheduling constraint or a receipt of information for selecting transmission or reception directions, transmission or reception directions for a first beam and a second beam (e.g., previously selected) for communications between the second WCD and a first WCD using a full duplex operation; means for transmitting, to the first WCD, an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications; and/or the like. In some aspects, such means may include one or more components of base station110described in connection withFIG.2, such as antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, transmit processor220, TX MIMO processor230, MOD232, antenna234, and/or the like.

FIG.3is a diagram illustrating examples300,310, and320of channel state information (CSI) reference signal (CSI-RS) beam management procedures, in accordance with the present disclosure. As shown inFIG.3, examples300,310, and320include a UE in communication with a base station in a wireless network (e.g., wireless network100). However, the devices shown inFIG.3are provided as examples, and the wireless network may support communication and beam management between other devices (e.g., between a UE120and a base station110or TRP, between a mobile termination node and a control node, between an IAB child node and an IAB parent node, between a scheduled node and a scheduling node, and/or the like). In some aspects, the UE120and the base station110may be in a connected state (e.g., a radio resource control (RRC) connected state and/or the like).

As shown inFIG.3, example300may include a base station110and a UE120communicating to perform beam management using CSI-RSs. Example300depicts a first beam management procedure (e.g., P1 CSI-RS beam management). The first beam management procedure may be referred to as a beam selection procedure, an initial beam acquisition procedure, a beam sweeping procedure, a cell search procedure, a beam search procedure, and/or the like. As shown inFIG.3and example300, CSI-RSs may be configured to be transmitted from the base station110to the UE120. The CSI-RSs may be configured to be periodic (e.g., using RRC signaling and/or the like), semi-persistent (e.g., using medium access control (MAC) control element (MAC CE) signaling and/or the like), and/or aperiodic (e.g., using downlink control information (DCI) and/or the like).

The first beam management procedure may include the base station110performing beam sweeping over multiple transmit (Tx) beams. The base station110may transmit a CSI-RS using each transmit beam for beam management. To enable the UE120to perform receive (Rx) beam sweeping, the base station may use a transmit beam to transmit (e.g., with repetitions) each CSI-RS at multiple times within the same RS resource set so that the UE120can sweep through receive beams in multiple transmission instances. For example, if the base station110has a set of N transmit beams and the UE120has a set of M receive beams, the CSI-RS may be transmitted on each of the N transmit beams M times so that the UE120may receive M instances of the CSI-RS per transmit beam. In other words, for each transmit beam of the base station110, the UE120may perform beam sweeping through the receive beams of the UE120. As a result, the first beam management procedure may enable the UE120to measure a CSI-RS on different transmit beams using different receive beams to support selection of base station110transmit beams/UE120receive beam(s) beam pair(s). The UE120may report (e.g., in a CSI report) the measurements to the base station110to enable the base station110to select one or more beam pair(s) for communication between the base station110and the UE120. While example300has been described in connection with CSI-RSs, the first beam management process may also use synchronization signal blocks (SSBs) for beam management in a similar manner as described above.

As shown inFIG.3, example310may include a base station110and a UE120communicating to perform beam management using CSI-RSs. Example310depicts a second beam management procedure (e.g., P2 CSI-RS beam management). The second beam management procedure may be referred to as a beam refinement procedure, a base station beam refinement procedure, a TRP beam refinement procedure, a transmit beam refinement procedure, and/or the like. As shown inFIG.3and example310, CSI-RSs may be configured to be transmitted from the base station110to the UE120. The CSI-RSs may be configured to be aperiodic (e.g., using DCI and/or the like). The second beam management procedure may include the base station110performing beam sweeping over one or more transmit beams. The one or more transmit beams may be a subset of all transmit beams associated with the base station110(e.g., determined based at least in part on measurements reported by the UE120in connection with the first beam management procedure). The base station110may transmit a CSI-RS using each transmit beam of the one or more transmit beams for beam management. The UE120may measure each CSI-RS using a single (e.g., a same) receive beam (e.g., determined based at least in part on measurements performed in connection with the first beam management procedure). The second beam management procedure may enable the base station110to select a best transmit beam based at least in part on measurements of the CSI-RSs (e.g., measured by the UE using the single receive beam) reported by the UE120.

As shown inFIG.3, example320depicts a third beam management procedure (e.g., P3 CSI-RS beam management). The third beam management procedure may be referred to as a beam refinement procedure, a UE beam refinement procedure, a receive beam refinement procedure, and/or the like. As shown inFIG.3and example320, one or more CSI-RSs may be configured to be transmitted from the base station110to the UE120. The CSI-RSs may be configured to be aperiodic (e.g., using DCI and/or the like). The third beam management process may include the base station110transmitting the one or more CSI-RSs using a single transmit beam (e.g., determined based at least in part on measurements reported by the UE120in connection with the first beam management procedure and/or the second beam management procedure). To enable the UE120to perform receive beam sweeping, the base station may use a transmit beam to transmit (e.g., with repetitions) the CSI-RS at multiple times within the same RS resource set so that UE120can sweep through one or more receive beams in multiple transmission instances. The one or more receive beams may be a subset of all receive beams associated with the UE120(e.g., determined based at least in part on measurements performed in connection with the first beam management procedure and/or the second beam management procedure). The third beam management procedure may enable the base station110and/or the UE120to select a best receive beam based at least in part on reported measurements received from the UE120(e.g., of the CSI-RS of the transmit beam using the one or more receive beams).

As indicated above,FIG.3is provided as an example of beam management procedures. Other examples of beam management procedures may differ from what is described with respect toFIG.3. For example, the UE and the base station may perform the third beam management procedure before performing the second beam management procedure, the UE and the base station may perform a similar beam management procedure to select a UE transmit beam, and/or the like.

Some UEs and/or base stations may support full duplex operation in which the UEs and/or the base stations support simultaneous transmission and reception. For example, a UE may support transmission via a first beam (e.g., using a first antenna panel) and may simultaneously support reception via a second beam (e.g., using a second antenna panel). Support for simultaneous transmission and reception may be conditional on beam separation, such as spatial separation (e.g., using different beams), frequency separation, and/or the like. Additionally, or alternatively, support for simultaneous transmission may be conditional on using beamforming (e.g., in frequency range 2 (FR2), in frequency range 4 (FR4), for millimeter wave signals, and/or the like).

A base station may select a first beam and a second beam for the UE to use in a full duplex operation (e.g., based at least in part on a beam management procedure). The base station may assign the first beam for the UE to use for reception and the second beam for the UE to use for transmission. The base station may indicate assignments for transmission and reception directions and may begin communicating with the UE based at least in part on the assignments. The base station may assign the first beam for transmission and the second beam for reception based at least in part on a CSI report indicating channel quality without awareness of local conditions of the UE and/or self-interference. This may degrade performance of communicating using the full duplex operation, which may cause communication errors and may consume computing, communication, network, and power resources to detect and/or recover from the communication errors, to communicate using lower modulation and coding schemes (MCS), and/or the like.

In some aspects described herein, a first wireless communication device (WCD) (e.g., UE120, an IAB node, and/or the like) may transmit information for selecting transmission and/or reception directions for a first beam and a second beam that have been selected as a candidate beam pair for communications between the first WCD and a second WCD (e.g., base station110, an IAB node, a parent node, a distributed unit, a central unit, and/or the like in an IAB network) using a full duplex operation. The second WCD may receive the information and may determine, based at least in part on the information and/or scheduling constraints, that the first WCD is to use the first beam to receive communications and the second beam to transmit communications. The second WCD may transmit, and the first WCD may receive, an indication to use the first beam to receive communications and the second beam to transmit communications.

In some aspects, the first WCD may transmit the information before initiating the full duplex operation and the indication may indicate to initiate a full duplex operation using the first beam to receive communications and the second beam to transmit communications. In some aspects, the first WCD may transmit the information while operating in the full duplex operation and the indication may indicate to switch a configuration of transmission and/or reception directions while already using the full duplex operation to use the first beam to receive communications and the second beam to transmit communications (e.g., switching away from using the second beam to receive communications and the first beam to transmit communications).

In some aspects, the information may include an indication of requested transmission and reception directions for the first beam and the second beam, a request to switch transmission and reception directions of the first beam and the second beam, and/or the like. In some aspects, the information may include an indication of one or more channel conditions associated with the first beam and the second beam, an indication of one or more local conditions determined by the first WCD, and/or the like.

Based at least in part on the first WCD transmitting the information for selecting transmission or reception directions for the first beam and the second beam (e.g., previously selected) for communications using a full duplex operation, the second WCD may assign the transmission or reception directions with awareness of local conditions of the first WCD and/or channel conditions when using the full duplex operation. This may improve performance of the full duplex operation, which may improve spectral efficiency and lower error rates, which may conserve computing, communication, network, and power resources.

FIG.4is a diagram illustrating an example400associated with beam direction selection for transmission and reception in full duplex operation, in accordance with the present disclosure. As shown inFIG.4, a first WCD (e.g., UE120, an IAB node, and/or the like) may communicate with a second WCD (e.g., base station110, an IAB node, a parent node, a distributed unit, a central unit, and/or the like in an IAB network). The first WCD and the second WCD may be part of a wireless network (e.g., wireless network100). In some aspects, the first WCD and the second WCD may be configured to communicate using millimeter wave signals, beamforming, a full duplex operation, and/or the like.

As shown by reference number405, the second WCD may transmit, and the first WCD may receive, configuration information. In some aspects, the first WCD may receive the configuration information from another device (e.g., from another WCD and/or the like), from a specification of a communication standard, and/or the like. In some aspects, the first WCD may receive the configuration information via one or more of RRC signaling, medium access control (MAC) signaling (e.g., MAC control elements (MAC CEs)), and/or the like. In some aspects, the configuration information may include an indication of one or more configuration parameters (e.g., already known to the first WCD) for selection by the first WCD, explicit configuration information for the first WCD to use to configure the first WCD, and/or the like.

In some aspects, the configuration information may indicate that the first WCD is to perform one or more beam management procedures, such as a beam selection procedure, to select one or more beams for communicating with the second WCD. In some aspects, the configuration information may indicate that the first WCD is to provide information for selecting transmission or reception directions for beams to be used in a full duplex operation.

As shown by reference number410, the first WCD may configure the first WCD for communicating with the second WCD. In some aspects, the first WCD may configure the first WCD based at least in part on the configuration information. In some aspects, the first WCD may be configured to perform one or more operations described herein.

As shown by reference number415, the first WCD and the second WCD may perform an initial beam management procedure. For example, the first WCD may perform a beam selection procedure, the second WCD may perform a beam refinement procedure, the first WCD may perform a beam refinement procedure, and/or the like. Based at least in part on the initial beam management procedure, the first WCD and the second WCD may select a beam pair for communicating. In some aspects, the first WCD and the second WCD may select the beam pair based at least in part on conditions at a time of selection or prior to the time of selection. For example, the first WCD and the second WCD may select the beam pair based at least in part on CSI that is measured and/or reported at the time of selection or prior to the time of selection.

As shown by reference number420, the first WCD and the second WCD may communicate via a first beam and a second beam using a full duplex operation. For example, the second WCD may select the first beam for the first WCD to use to transmit communications and the second beam for the first WCD to use to receive communications. In some aspects, the second WCD may select transmission or reception directions for the first beam and the second beam based at least in part on CSI that is reported and/or measured at the time of selection of the first beam and the second beam, or prior to the time of selection.

As shown by reference number425, the first WCD may receive, and the second WCD may transmit, one or more reference signals via the first beam and the second beam. In some aspects, the first WCD may receive the one or more reference signals without first communicating with the second WCD via the first beam and the second beam, as shown with reference to reference number420.

As shown by reference number430, the first WCD may transmit one or more signals for interference measurement. For example, the first WCD may transmit one or more signals via the first beam and the second beam to be measured to determine self-interference when receiving reference signals via the second beam and the first beam.

As shown by reference number435, the first WCD may determine local conditions and/or channel conditions associated with using the first beam and the second beam for the full duplex operation.

In some aspects, the one or more local conditions may include conditions associated with, and/or observed at, the first WCD. In some aspects, the one or more local conditions may include a thermal imbalance between a first antenna array associated with the first beam and a second antenna array associated with the second beam, overheating of the first antenna array or the second antenna array, a maximum permissible exposure event associated with the first antenna array or the second antenna array, and/or the like. For example, the first WCD may determine that a first antenna panel associated with transmitting via the first beam is overheated and/or has a thermal imbalance with a second antenna panel associated with receiving via the second beam. In some aspects, the first WCD may detect a maximum permissible exposure event associated with transmitting via the first beam, which may prevent the first WCD from transmitting via the first beam with sufficient power for communication with the second WCD using current communication parameters. In some aspects, the first WCD may determine that selecting transmission or reception directions of the first beam and the second beam, or switching the transmission or reception directions, may improve communication with the second WCD based at least in part on the one or more local conditions.

In some aspects, the first WCD may determine one or more channel conditions associated with the first beam and the second beam. In some aspects, the WCD may determine the one or more channel conditions based at least in part on receiving the one or more reference signals via the first beam and the second beam, based at least in part on transmitting the signals for the interference measurement, and/or the like. In some aspects, determining the one or more channel conditions may include determining a first signal-to-interference-plus-noise ratio (SINR) for the first beam for transmitting and a second SINR for the second beam for transmitting, determining a first CQI for the first beam for transmitting and a second CQI for the second beam for transmitting, determining a first power headroom for the first beam for transmitting and a second power headroom for the second beam for transmitting, and/or the like.

In some aspects, the first WCD may determine the first SINR based at least in part on a measured signal strength of a first reference signal associated with the first beam (e.g., transmitted by the second WCD and received via the first beam) and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam. In some aspects, the first WCD may determine the second SINR based at least in part on a measured signal strength of a second reference signal associated with the second beam (transmitted by the second WCD and received via the second beam) and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

In some aspects, the first WCD may determine the first CQI based at least in part on a measured signal strength of a first reference signal associated with the first beam (e.g., transmitted by the second WCD and received via the first beam) and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam. In some aspects, the first WCD may determine the second CQI based at least in part on a measured signal strength of a second reference signal associated with the second beam (transmitted by the second WCD and received via the second beam) and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

In some aspects, the first WCD may determine the first power headroom based at least in part on a first self-interference threshold to limit interference from transmissions via the first beam with receptions via the second beam. In some aspects, the first WCD may determine the second power headroom based at least in part on a second self-interference threshold to limit interference from transmissions via the second beam with receptions via the first beam.

As shown by reference number440, the first WCD may transmit information for selecting transmission or reception directions for the first beam and the second beam (e.g., (e.g., previously selected) for communications between the first WCD and the second WCD using a full duplex operation). In some aspects, the first WCD may transmit the information via one or more of an uplink control information (UCI) message, one or more MAC-CEs, RRC signaling, and/or the like. For example, the first WCD may transmit the information within a CSI report via a UCI message, one or more MAC-CEs, RRC signaling, and/or the like.

In some aspects, the first WCD may determine to transmit the information for selecting transmission or reception directions based at least in part on a request (e.g., from the second WCD) for the information for selecting transmission or reception directions, a process for initiating the full duplex operation, one or more local conditions determined by the first WCD, determining channel conditions associated with the first beam and the second beam, and/or the like.

In some aspects, the information may include an indication of requested transmission and reception directions for the first beam and the second beam, an indication of a request to switch transmission and reception directions of the first beam and the second beam (e.g., switch a current transmission or reception direction of the first beam and the second beam), an indication of one or more channel conditions associated with the first beam and the second beam, an indication of one or more local conditions determined by the first WCD, and/or the like. In some aspects, the information may include indications of one or more channel conditions (e.g., SINR) associated with the first beam, and one or more channel conditions (e.g., SINR) associated with the second beam. For example, the information may include SINR for reception via the first beam when transmitting via the second beam and may include SINR for reception via the second beam when transmitting via the first beam.

In some aspects, the first WCD may transmit the information for selecting transmission or reception directions for the first beam and the second beam as part of a beam selection process (e.g., in connection with performing the initial beam management procedure described in connection with reference number415). For example, the first WCD may transmit the information before initiating communications via the first beam and the second beam. In some aspects, the first WCD may transmit the information for selecting transmission or reception directions for the first beam and the second beam as a request to change transmission or reception directions from directions previously used and/or configured as part of a beam selection process (e.g., in connection with performing the initial beam management procedure described in connection with reference number415). For example, the first WCD may transmit the information after communicating via the first beam and the second beam using the first beam for transmission and using the second beam for reception.

As shown by reference number445, the second WCD may determine transmission or reception directions for the first beam and the second beam. In some aspects, the second WCD may determine the transmission or reception directions for the first beam and the second beam based at least in part on the information for selecting transmission or reception directions. Additionally, or alternatively, the second WCD may determine the transmission or reception directions for the first beam and the second beam based at least in part on a scheduling constraint (e.g., an inability to use one of the first beam or the second beam for a transmission or reception direction based at least in part on transmitting or receive communications with one or more other WCDs).

As shown by reference number450, the first WCD may receive, and the second WCD may transmit, an indication to use the first beam to receive communications and the second beam to transmit communications using the full duplex operation. In some aspects, the first WCD may receive the indication via RRC signaling, a DCI message, one or more MAC CEs, and/or the like. In some aspects, the indication may include an indication of a transmission configuration indicator (TCI) state or spatial relation information for the first beam and an indication of a TCI state or spatial relation information for the second beam.

In some aspects, the indication may indicate to initiate the full duplex operation with the first beam assigned to receive communications and with the second beam assigned to transmit communications. For example, the indication may be sent without first communicating via the first beam and the second beam as described with reference to reference number420. In some aspects, the indication may indicate to switch a configuration of the full duplex operation to using the first beam (e.g., from using the second beam or a third beam) to receive communications and to switch to using the second beam (e.g., from using the first beam or a fourth beam) to transmit communications.

In some aspects, the first WCD and the second WCD may communicate based at least part on the indication using the full duplex operation of the first WCD, including receiving one or more communications via the first beam and transmitting one or more communications via the second beam.

Based at least in part on the first WCD transmitting the information for selecting transmission or reception directions for the first beam and the second beam, the second WCD may assign the transmission or reception directions with awareness of local conditions of the first WCD and/or channel conditions when using the full duplex operation. This may improve performance of the full duplex operation, which may improve spectral efficiency and lower error rates, which may conserve computing, communication, network, and power resources.

FIG.5is a diagram illustrating examples500and550associated with beam direction selection for transmission and reception in full duplex operation, in accordance with the present disclosure. As shown inFIG.5, a UE (e.g., UE120) may communicate with a base station (e.g., base station110). The UE and the base station may be part of a wireless network (e.g., wireless network100). In some aspects, the UE and the base station may be configured to communicate using millimeter wave signals, beamforming, a full duplex operation, and/or the like.

As shown by reference number505, the UE may receive, and the base station may transmit, communication via a first beam pair (e.g., a base station transmit beam and a UE receive beam, a downlink beam pair, and/or the like). As shown by reference number510, the UE may transmit, and the base station may receive, communications via a second beam pair (e.g., a base station receive beam and a UE transmit beam, an uplink beam pair, and/or the like).

As shown by reference number555, the UE may transmit, and the base station may receive, communication via the first beam pair (e.g., a base station receive beam and a UE transmit beam, an uplink beam pair, and/or the like). As shown by reference number560, the UE may receive, and the base station may transmit, communications via the second beam pair (e.g., a base station transmit beam and a UE receive beam, an uplink beam pair, and/or the like).

In some aspects, the UE may determine and/or transmit information for selecting transmission or reception directions for a first beam (e.g., a UE beam of the first beam pair) and a second beam (e.g., a UE beam of the second beam pair). The base station may determine transmission or reception directions for the first beam and the second beam based at least in part on the information and/or scheduling constraints. In some aspects, the base station may determine to operate in a configuration represented by example500or example550to initiate a full duplex operation. In some aspects, the base station may determine to switch from using the configuration represented by example500to using the configuration represented by example550, or to switch from using the configuration represented by example500to using the configuration represented by example550.

FIG.6is a diagram illustrating examples600and650associated with beam direction selection for transmission and reception in full duplex operation, in accordance with the present disclosure. As shown inFIG.6, a UE (e.g., UE120) may communicate with multiple TRPs. The UE and the multiple TRPs (e.g., base stations110) may be part of a wireless network (e.g., wireless network100). In some aspects, the UE and the multiple TRPs may be configured to communicate using millimeter wave signals, beamforming, a full duplex operation, and/or the like.

As shown by reference number605, the UE may receive, and a first TRP (TRP1) may transmit, communications via a first beam pair (e.g., a TRP transmit beam and a UE receive beam, a downlink beam pair, and/or the like). As shown by reference number610, the UE may transmit, and a second TRP (TRP2) may receive, communications via a second beam pair (e.g., a TRP receive beam and a UE transmit beam, an uplink beam pair, and/or the like).

As shown by reference number655, the UE may transmit, and the first TRP may receive, communication via the first beam pair (e.g., a TRP receive beam and a UE transmit beam, an uplink beam pair, and/or the like). As shown by reference number660, the UE may receive, and the second TRP may transmit, communications via the second beam pair (e.g., a TRP transmit beam and a UE receive beam, an uplink beam pair, and/or the like).

In some aspects, the UE may determine and/or transmit information for selecting transmission or reception directions for the first beam (e.g., a UE beam of the first beam pair) and the second beam (e.g., a UE beam of the second beam pair). The first TRP, the second TRP, a base station (e.g., that operates a serving cell that includes the first TRP and the second TRP), and/or the like may determine transmission or reception directions for the first beam pair and the second beam pair based at least in part on the information and/or scheduling constraints. In some aspects, the first TRP, the second TRP, the base station and/or the like may determine to operate in a configuration represented by example600or example650to initiate a full duplex operation. In some aspects, the first TRP, the second TRP, the base station and/or the like may determine to switch from using the configuration represented by example600to using the configuration represented by example650, or to switch from using the configuration represented by example650to using the configuration represented by example600.

FIG.7is a diagram illustrating examples700,710,720, and730associated with beam direction selection for transmission and reception in full duplex operation, in accordance with the present disclosure. As shown inFIG.7, an IAB node (e.g., a base station110) may communicate with a parent node and multiple child nodes (e.g., base stations110, UEs120, and/or the like). The IAB node, the parent node, and the multiple child nodes may be part of a wireless network (e.g., wireless network100). In some aspects, the IAB node, the parent node, and the multiple child nodes may be configured to communicate using millimeter wave signals, beamforming, a full duplex operation, and/or the like.

As shown by reference number700the IAB node may concurrently receive communications (e.g., downlink communications) from the parent node and receive communications (e.g., uplink communications) from the multiple child nodes.

As shown by reference number710the IAB node may concurrently transmit communications (e.g., uplink communications) to the parent node and transmit communications (e.g., downlink communications) to the multiple child nodes.

As shown by reference number720the IAB node may concurrently transmit communications (e.g., uplink communications) to the parent node and receive communications (e.g., uplink communications) from the multiple child nodes.

As shown by reference number730the IAB node may concurrently receive communications (e.g., downlink communications) from the parent node and transmit communications (e.g., downlink communications) to the multiple child nodes.

In some aspects, the IAB node may determine and/or transmit information for selecting transmission or reception directions for a first beam (e.g., a beam for communications between the IAB node and the parent node) and one or more second beams (e.g., one or more beams for communications between the IAB node and the multiple child nodes). The parent node may determine transmission or reception directions for the first beam and the one or more second beams based at least in part on the information and/or scheduling constraints. In some aspects, the parent node may determine to operate in a configuration represented by example700, example710, example720, or example730to initiate a full duplex operation of the IAB node. In some aspects, the parent node may determine to switch from using the configuration represented by example700, example710, example720, or example730to using a different configuration represented by example700, example710, example720, or example730.

FIG.8is a diagram illustrating examples800,810,820, and830associated with beam direction selection for transmission and reception in full duplex operation, in accordance with the present disclosure. As shown inFIG.8, a child node (e.g., a UE120) may communicate with multiple parent nodes (e.g., base stations110). The child node and the multiple parent nodes may be part of a wireless network (e.g., wireless network100). In some aspects, the child node and/or the multiple parent nodes may be IAB nodes. In some aspects, the multiple parent nodes and the child node may be configured to communicate using millimeter wave signals, beamforming, a full duplex operation, and/or the like.

As shown by reference number800, the child node may concurrently receive communications (e.g., downlink communications) from a first parent node and a second parent node.

As shown by reference number810, the child node may concurrently transmit communications (e.g., uplink communications) to the first parent node and the second parent node.

As shown by reference number820, the child node may concurrently transmit communications to the first parent node and receive communications from the second parent node.

As shown by reference number830, the child node may concurrently receive communications from the first parent node and transmit communications to the second parent node.

In some aspects, the child node may determine and/or transmit information for selecting transmission or reception directions for a first beam (e.g., a beam for communications between the child node and the first parent node) and a second beam (e.g., a beam for communications between the child node and the second parent node). One or more of the multiple parent nodes may determine transmission or reception directions for the first beam and the second beam based at least in part on the information and/or scheduling constraints. In some aspects, the one or more of the multiple parent nodes may determine to operate in a configuration represented by example800, example810, example820, or example830to initiate a full duplex operation of the child node. In some aspects, the one or more of the multiple parent nodes may determine to switch from using the configuration represented by example800, example810, example820, or example830to using a different configuration represented by example800, example810, example820, or example830.

FIG.9is a diagram illustrating an example process900performed, for example, by a first WCD, in accordance with the present disclosure. Example process900is an example where the first WCD (e.g., UE120, an IAB node, and/or the like) performs operations associated with beam direction selection for transmission and reception in full duplex operation.

As shown inFIG.9, in some aspects, process900may include transmitting, to a second WCD, information for selecting transmission or reception directions for a first beam and a second beam (e.g., previously selected) for communications between the first WCD and the second WCD using a full duplex operation (block910). For example, the first WCD (e.g., using controller/processor280, transmit processor264, TX MIMO processor266, MOD254, antenna252, and/or the like) may transmit, to a second WCD, information for selecting transmission or reception directions for a first beam and a second beam (e.g., previously selected) for communications between the first WCD and the second WCD using a full duplex operation, as described above.

As further shown inFIG.9, in some aspects, process900may include receiving an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications (block920). For example, the first WCD (e.g., using antenna252, DEMOD254, MIMO detector256, receive processor258, controller/processor280, and/or the like) may receive an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications, as described above.

In a first aspect, process900includes determining to transmit the information for selecting transmission or reception directions for the first beam and the second beam based at least in part on one or more local conditions determined by the first WCD.

In a second aspect, alone or in combination with the first aspect, the one or more local conditions determined by the first WCD include one or more of: a thermal imbalance between a first antenna array associated with the first beam and a second antenna array associated with the second beam, overheating of the first antenna array or the second antenna array, or a maximum permissible exposure event associated with the first antenna array or the second antenna array.

In a third aspect, alone or in combination with one or more of the first and second aspects, process900includes determining channel conditions associated with the first beam and the second beam, and determining, based at least in part on the channel conditions, to transmit the information for selecting transmission or reception directions for the first beam and the second beam.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, determining the channel conditions associated with the first beam and the second beam includes receiving one or more reference signals via the first beam and the second beam, and determining one or more of a first SINR for the first beam and a second SINR for the second beam, a first CQI for the first beam and a second CQI for the second beam, or a first power headroom for the first beam and a second power headroom for the second beam.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, process900includes determining the first SINR based at least in part on a measured signal strength of a first reference signal associated with the first beam transmitted by the second WCD and received via the first beam, and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam, and determining the second SINR based at least in part on a measured signal strength of a second reference signal associated with the second beam transmitted by the second WCD and received via the second beam, and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, process900includes determining the first CQI based at least in part on a measured signal strength of a first reference signal associated with the first beam transmitted by the second WCD and received via the first beam, and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam, and determining the second CQI based at least in part on a measured signal strength of a second reference signal associated with the second beam transmitted by the second WCD and received via the second beam, and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, process900includes determining the first power headroom based at least in part on a first self-interference threshold to limit interference from transmissions via the first beam with receptions via the second beam, and determining the second power headroom based at least in part on a second self-interference threshold to limit interference from transmissions via the second beam with receptions via the first beam.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, process900includes receiving a request, from the second WCD, for the information for selecting transmission or reception directions for the first beam and the second beam.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the information for selecting transmission or reception directions for the first beam and the second beam includes one or more of an indication of requested transmission and reception directions for the first beam and the second beam, an indication of one or more channel conditions associated with the first beam and the second beam, an indication of one or more local conditions determined by the first WCD, or an indication of a request to switch transmission and reception directions of the first beam and the second beam.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, transmitting the information for selecting transmission or reception directions for the first beam and the second beam includes transmitting the information for selecting transmission or reception directions for the first beam and the second beam via one or more of a CSI report, a UCI message, one or more MAC CEs, or RRC signaling.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the indication to use the first beam to receive communications and the second beam to transmit communications includes an indication to initiate the full duplex operation with the first beam assigned to receive communications and with the second beam assigned to transmit communications, an indication to switch a configuration of the full duplex operation to using the first beam from using the second beam to receive communications and to using the second beam from using the first beam to transmit communications, or an indication to switch a configuration of full duplex operation to using the first beam from using a third beam to receive communications and to using the second beam from using a fourth beam to transmit communications.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the indication to use the first beam to receive communications and the second beam to transmit communications includes an indication of a TCI state or spatial relation information for the first beam, and an indication of a TCI state or spatial relation information for the second beam.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, receiving the indication to use the first beam to receive communications and the second beam to transmit communications includes receiving the indication to use the first beam to receive communications and the second beam to transmit communications via one or more of RRC signaling, a downlink control information message, or one or more MAC CEs.

In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, the first WCD includes one or more of a UE, or an IAB node.

In a fifteenth aspect, alone or in combination with one or more of the first through fourteenth aspects, process900includes receiving one or more communications via the first beam using the full duplex operation of the first WCD, and transmitting one or more communications via the second beam using the full duplex operation of the first WCD.

FIG.10is a diagram illustrating an example process1000performed, for example, by a second WCD, in accordance with the present disclosure. Example process1000is an example where the second WCD (e.g., base station110, an IAB node, a parent node, a distributed unit, a central unit, and/or the like in an IAB network) performs operations associated with beam direction selection for transmission and reception in full duplex operation.

As shown inFIG.10, in some aspects, process1000may include determining, based at least in part on one or more of a scheduling constraint or a receipt of information for selecting transmission or reception directions, transmission or reception directions for a first beam and a second beam (e.g., previously selected) for communications between the second WCD and a first WCD using a full duplex operation (block1010). For example, the second WCD (e.g., using controller/processor240and/or the like) may determine, based at least in part on one or more of a scheduling constraint or a receipt of information for selecting transmission or reception directions, transmission or reception directions for a first beam and a second beam (e.g., previously selected) for communications between the second WCD and a first WCD using a full duplex operation, as described above.

As further shown inFIG.10, in some aspects, process1000may include transmitting, to the first WCD, an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications (block1020). For example, the second WCD (e.g., using controller/processor240, transmit processor220, TX MIMO processor230, MOD232, antenna234, and/or the like) may transmit, to the first WCD, an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications, as described above.

In a first aspect, the information for selecting transmission or reception directions for the first beam and the second beam includes one or more of an indication of requested transmission and reception directions for the first beam and the second beam, an indication of one or more channel conditions associated with the first beam and the second beam, an indication of one or more local conditions determined by the first WCD, or an indication of a request to switch transmission and reception directions of the first beam and the second beam.

In a second aspect, alone or in combination with the first aspect, the one or more local conditions determined by the first WCD include one or more of a thermal imbalance between a first antenna array associated with the first beam and a second antenna array associated with the second beam, overheating of the first antenna array or the second antenna array, or a maximum permissible exposure event associated with the first antenna array or the second antenna array.

In a third aspect, alone or in combination with one or more of the first and second aspects, the one or more channel conditions associated with the first beam and the second beam include a first SINR for the first beam and a second SINR for the second beam, a first CQI for the first beam and a second CQI for the second beam, or a first power headroom for the first beam and a second power headroom for the second beam.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the first SINR is based at least in part on a measured signal strength of a first reference signal associated with the first beam transmitted by the second WCD and received via the first beam, and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam, and wherein the second SINR is based at least in part on a measured signal strength of a second reference signal associated with the second beam transmitted by the second WCD and received via the second beam, and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the first CQI is based at least in part on a measured signal strength of a first reference signal associated with the first beam transmitted by the second WCD and received via the first beam, and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam, and wherein the second CQI is based at least in part on a measured signal strength of a second reference signal associated with the second beam transmitted by the second WCD and received via the second beam, and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the first power headroom is based at least in part on a first self-interference threshold to limit interference from transmissions via the first beam on receptions by the first WCD via the second beam, and wherein the second power headroom is based at least in part on a second self-interference threshold to limit interference from transmissions via the second beam on receptions by the first WCD via the first beam.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, process1000includes transmitting one or more reference signals via the first beam and the second beam, and receiving an indication of one or more channel conditions associated with the first beam and the second beam, wherein determining the transmission or reception directions for the first beam and the second beam is based at least in part on the indication of the one or more channel conditions associated with the first beam and the second beam.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, process1000includes receiving the information for selecting transmission or reception directions for the first beam and the second beam via one or more of a CSI report, a UCI message, one or more MAC CEs, or RRC signaling.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the indication to use the first beam for the first WCD to receive communications and the second beam for the first WCD to transmit communications includes an indication to initiate the full duplex operation with the first beam assigned to receive communications and with the second beam assigned to transmit communications, an indication to switch a configuration of the full duplex operation to using the first beam from using the second beam to receive communications and to using the second beam from using the first beam to transmit communications, or an indication to switch a configuration of full duplex operation to using the first beam from using a third beam to receive communications and to using the second beam from using a fourth beam to transmit communications.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the indication to use the first beam to receive communications and the second beam to transmit communications includes an indication of a TCI state or spatial relation information for the first beam, and an indication of a TCI state or spatial relation information for the second beam.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, transmitting the indication to use the first beam to receive communications and the second beam to transmit communications includes transmitting the indication to use the first beam to receive communications and the second beam to transmit communications via one or more of RRC signaling, a downlink control information message, or one or more MAC CEs.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the second WCD includes one or more of a base station, or an IAB node, or a parent node, a distributed unit, or a central unit in an IAB network.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, process1000includes transmitting one or more communications via the first beam using the full duplex operation of the first WCD, and receiving one or more communications via the second beam using the full duplex operation of the first WCD.

In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, process1000includes transmitting a request for the information for selecting transmission or reception directions for the first beam and the second beam.

Aspect 1: A method of wireless communication performed by a first wireless communication device (WCD), comprising: transmitting, to a second WCD, information for selecting transmission or reception directions for a first beam and a second beam for communications between the first WCD and the second WCD using a full duplex operation; and receiving an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications.

Aspect 2: The method of Aspect 1, further comprising: determining to transmit the information for selecting transmission or reception directions for the first beam and the second beam based at least in part on one or more local conditions determined by the first WCD.

Aspect 3: The method of Aspect 2, wherein the one or more local conditions determined by the first WCD comprise one or more of: a thermal imbalance between a first antenna array associated with the first beam and a second antenna array associated with the second beam, overheating of the first antenna array or the second antenna array, or a maximum permissible exposure event associated with the first antenna array or the second antenna array.

Aspect 4: The method of any of Aspects 1-3, further comprising: determining channel conditions associated with the first beam and the second beam, and determining, based at least in part on the channel conditions, to transmit the information for selecting transmission or reception directions for the first beam and the second beam.

Aspect 5: The method of Aspect 4, wherein determining the channel conditions associated with the first beam and the second beam comprises: receiving one or more reference signals via the first beam and the second beam, and determining one or more of: a first signal-to-interference-plus-noise ratio (SINR) for the first beam and a second SINR for the second beam, a first channel quality indicator (CQI) for the first beam and a second CQI for the second beam, or a first power headroom for the first beam and a second power headroom for the second beam.

Aspect 6: The method of Aspect 5, further comprising: determining the first SINR based at least in part on: a measured signal strength of a first reference signal associated with the first beam transmitted by the second WCD and received via the first beam, and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam, and determining the second SINR based at least in part on: a measured signal strength of a second reference signal associated with the second beam transmitted by the second WCD and received via the second beam, and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

Aspect 7: The method of Aspect 5, further comprising: determining the first CQI based at least in part on: a measured signal strength of a first reference signal associated with the first beam transmitted by the second WCD and received via the first beam, and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam, and determining the second CQI based at least in part on: a measured signal strength of a second reference signal associated with the second beam transmitted by the second WCD and received via the second beam, and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

Aspect 8: The method of Aspect 5, further comprising: determining the first power headroom based at least in part on a first self-interference threshold to limit interference from transmissions via the first beam with receptions via the second beam, and determining the second power headroom based at least in part on a second self-interference threshold to limit interference from transmissions via the second beam with receptions via the first beam.

Aspect 9: The method of any of Aspects 1-8, further comprising: receiving a request, from the second WCD, for the information for selecting transmission or reception directions for the first beam and the second beam.

Aspect 10: The method of any of Aspects 1-9, wherein the information for selecting transmission or reception directions for the first beam and the second beam comprises one or more of: an indication of requested transmission and reception directions for the first beam and the second beam, an indication of one or more channel conditions associated with the first beam and the second beam, an indication of one or more local conditions determined by the first WCD, or an indication of a request to switch transmission and reception directions of the first beam and the second beam.

Aspect 11: The method of any of Aspects 1-10, wherein transmitting the information for selecting transmission or reception directions for the first beam and the second beam comprises: transmitting the information for selecting transmission or reception directions for the first beam and the second beam via one or more of: a channel state information report, an uplink control information message, one or more medium-access-control control elements, or radio resource control signaling.

Aspect 12: The method of any of Aspects 1-11, wherein the indication to use the first beam to receive communications and the second beam to transmit communications comprises: an indication to initiate the full duplex operation with the first beam assigned to receive communications and with the second beam assigned to transmit communications, an indication to switch a configuration of the full duplex operation to using the first beam from using the second beam to receive communications and to using the second beam from using the first beam to transmit communications, or an indication to switch a configuration of full duplex operation to using the first beam from using a third beam to receive communications and to using the second beam from using a fourth beam to transmit communications.

Aspect 13: The method of any of Aspects 1-12, wherein the indication to use the first beam to receive communications and the second beam to transmit communications comprises: an indication of a transmission configuration indicator (TCI) state or spatial relation information for the first beam, and an indication of a TCI state or spatial relation information for the second beam.

Aspect 14: The method of any of Aspects 1-13, wherein receiving the indication to use the first beam to receive communications and the second beam to transmit communications comprises: receiving the indication to use the first beam to receive communications and the second beam to transmit communications via one or more of: radio resource control signaling, a downlink control information message, or one or more medium-access-control control elements.

Aspect 15: The method of any of Aspects 1-14, wherein the first WCD comprises one or more of: a user equipment, or an integrated access and backhaul node.

Aspect 16: The method of Aspect 1, further comprising: receiving one or more communications via the first beam using the full duplex operation of the first WCD; and transmitting one or more communications via the second beam using the full duplex operation of the first WCD.

Aspect 17: A method of wireless communication performed by a second wireless communication device (WCD), comprising: determining, based at least in part on one or more of a scheduling constraint or a receipt of information for selecting transmission or reception directions, transmission or reception directions for a first beam and a second beam for communications between the second WCD and a first WCD using a full duplex operation; and transmitting, to the first WCD, an indication to use, for the full duplex operation of the first WCD, the first beam to receive communications and the second beam to transmit communications.

Aspect 18: The method of Aspect 17, wherein the information for selecting transmission or reception directions for the first beam and the second beam comprises one or more of: an indication of requested transmission and reception directions for the first beam and the second beam, an indication of one or more channel conditions associated with the first beam and the second beam, an indication of one or more local conditions determined by the first WCD, or an indication of a request to switch transmission and reception directions of the first beam and the second beam.

Aspect 19: The method of Aspect 18, wherein the one or more local conditions determined by the first WCD comprise one or more of: a thermal imbalance between a first antenna array associated with the first beam and a second antenna array associated with the second beam, overheating of the first antenna array or the second antenna array, or a maximum permissible exposure event associated with the first antenna array or the second antenna array.

Aspect 20: The method of Aspect 18, wherein the one or more channel conditions associated with the first beam and the second beam comprise: a first signal-to-interference-plus-noise ratio (SINR) for the first beam and a second SINR for the second beam, a first channel quality indicator (CQI) for the first beam and a second CQI for the second beam, or a first power headroom for the first beam and a second power headroom for the second beam.

Aspect 21: The method of Aspect 20, wherein the first SINR is based at least in part on a measured signal strength of a first reference signal associated with the first beam transmitted by the second WCD and received via the first beam, and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam, and wherein the second SINR is based at least in part on a measured signal strength of a second reference signal associated with the second beam transmitted by the second WCD and received via the second beam, and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

Aspect 22: The method of Aspect 20, wherein the first CQI is based at least in part on a measured signal strength of a first reference signal associated with the first beam transmitted by the second WCD and received via the first beam, and a measured self-interference of a first signal transmitted by the first WCD via the second beam and received via the first beam, and wherein the second CQI is based at least in part on a measured signal strength of a second reference signal associated with the second beam transmitted by the second WCD and received via the second beam, and a measured self-interference of a second signal transmitted by the first WCD via the first beam and received via the second beam.

Aspect 23: The method of Aspect 20, wherein the first power headroom is based at least in part on a first self-interference threshold to limit interference from transmissions via the first beam on receptions by the first WCD via the second beam, and wherein the second power headroom is based at least in part on a second self-interference threshold to limit interference from transmissions via the second beam on receptions by the first WCD via the first beam.

Aspect 24: The method of any of Aspects 17-23, further comprising: transmitting one or more reference signals via the first beam and the second beam; and receiving an indication of one or more channel conditions associated with the first beam and the second beam, wherein determining the transmission or reception directions for the first beam and the second beam is based at least in part on the indication of the one or more channel conditions associated with the first beam and the second beam.

Aspect 25: The method of any of Aspects 17-24, further comprising: receiving the information for selecting transmission or reception directions for the first beam and the second beam via one or more of: a channel state information report, an uplink control information message, one or more medium-access-control control elements, or radio resource control signaling.

Aspect 26: The method of any of Aspects 17-25, wherein the indication to use the first beam for the first WCD to receive communications and the second beam for the first WCD to transmit communications comprises: an indication to initiate the full duplex operation with the first beam assigned to receive communications and with the second beam assigned to transmit communications, an indication to switch a configuration of the full duplex operation to using the first beam from using the second beam to receive communications and to using the second beam from using the first beam to transmit communications, or an indication to switch a configuration of full duplex operation to using the first beam from using a third beam to receive communications and to using the second beam from using a fourth beam to transmit communications.

Aspect 27: The method of any of Aspects 17-26, wherein the indication to use the first beam to receive communications and the second beam to transmit communications comprises: an indication of a transmission configuration indicator (TCI) state or spatial relation information for the first beam, and an indication of a TCI state or spatial relation information for the second beam.

Aspect 28: The method of any of Aspects 17-27, wherein transmitting the indication to use the first beam to receive communications and the second beam to transmit communications comprises: transmitting the indication to use the first beam to receive communications and the second beam to transmit communications via one or more of: radio resource control signaling, a downlink control information message, or one or more medium-access-control control elements.

Aspect 29: The method of any of Aspects 17-28, wherein the second WCD comprises one or more of: a base station, or an integrated access and backhaul (IAB) node, or a parent node, a distributed unit, or a central unit in an IAB network.

Aspect 30: The method of any of Aspects 17-29, further comprising: transmitting one or more communications via the first beam using the full duplex operation of the first WCD; and receiving one or more communications via the second beam using the full duplex operation of the first WCD.

Aspect 31: The method of any of Aspects 17-30, further comprising: transmitting a request for the information for selecting transmission or reception directions for the first beam and the second beam.