SIDELINK TRANSMISSION CONFIGURATION INDICATOR (TCI) STATE COMMAND CONFLICT RESOLUTION

Methods, systems, and devices for wireless communications are described. In some cases, a first user equipment (UE) may transmit, to a second UE, first control information indicating a first transmission configuration indicator (TCI) state for use in sidelink communications between the first UE and the second UE. The first UE may receive, from the second UE, second control information indicating a second TCI state for use in sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state. The first UE may select, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state. Accordingly, the first UE may communicate with the second UE in accordance with the selected TCI state.

FIELD OF TECHNOLOGY

The following relates to wireless communications, including sidelink transmission configuration indicator (TCI) state command conflict resolution.

BACKGROUND

SUMMARY

The described techniques relate to improved methods, systems, devices, and apparatuses that support sidelink transmission configuration indicator (TCI) state command conflict resolution. Generally, the techniques described herein may enable one or more user equipments (UEs) to avoid or resolve TCI state command confliction in sidelink communications. For example, a first UE may be in sidelink communications with a second UE and each UE may receive first control information that indicates a limitation to transmission of a potential TCI state, where the limitation restricts the first UE and the second UE from simultaneously applying different potential TCI states during the sidelink communications. In some examples, the limitation may define that only the first UE or the second UE is to transmit the potential TCI state. Additionally, or alternatively, the limitation may define that all potential TCI states used during the sidelink communications have a same time threshold for application of the potential TCI states. As such, the first UE may transmit, to the second UE, an indication of a first TCI state in accordance with the limitation and the UEs may communicate in accordance with the first TCI state.

Additionally, or alternatively, the first UE may transmit, to the second UE, first control information that indicates a first TCI state for use in the sidelink communications between the first UE and the second UE and may receive, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE. Accordingly, the first UE and the second UE may select one of the first TCI state or the second TCI state as a selected TCI state based on one or more rules for resolving sidelink TCI state conflicts. In some examples, the one or more rules may define that the selected TCI state is selected based on a comparison of a first priority associated with the first UE and a second priority associated with the second UE. Additionally, or alternatively, the one or more rules may define that the selected TCI state is selected based on a comparison of a first timing of a first acknowledgement message received in response to the first control information and a second timing of a second acknowledgement message transmitted in response to the second control information. As such, the first UE and the second UE may communicate in accordance with the selected TCI state.

A method for wireless communications at a first UE is described. The method may include receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications, transmitting, to the second UE, an indication of a first TCI state in accordance with the limitation, and communicating with the second UE in accordance with the first TCI state.

An apparatus for wireless communications at a first UE is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications, transmit, to the second UE, an indication of a first TCI state in accordance with the limitation, and communicate with the second UE in accordance with the first TCI state.

Another apparatus for wireless communications at a first UE is described. The apparatus may include means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications, means for transmitting, to the second UE, an indication of a first TCI state in accordance with the limitation, and means for communicating with the second UE in accordance with the first TCI state.

A non-transitory computer-readable medium storing code for wireless communications at a first UE is described. The code may include instructions executable by a processor to receive first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications, transmit, to the second UE, an indication of a first TCI state in accordance with the limitation, and communicate with the second UE in accordance with the first TCI state.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the limitation defines that only one of the first UE or the second UE may be to transmit the potential TCI state.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving, from the second UE, an indication of assistance information associated with the sidelink communications between the first UE and the second UE and determining the first TCI state based on the assistance information.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for determining that a type of the first UE matches a designated UE type specified by the limitation, the designated UE type representative of UEs allowed to transmit the potential TCI state in accordance with the limitation.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the designated UE type may be a RSU or a PLC.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the limitation defines that all potential TCI states used during the sidelink communications may have a same time threshold for application of the potential TCI states.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving, from the second UE, an acknowledgement message associated with the indication from the first UE of the first TCI state and applying the first TCI state to the sidelink communications with the second UE after receipt of the acknowledgement message and after the time threshold.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the time threshold may be defined in the first control information as a quantity of symbols that follows receipt of an acknowledgement message responsive to transmission of the indication of the first TCI state.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving, from the second UE, a second indication of a second TCI state, transmitting, to the second UE, a second acknowledgement message associated with the second indication from the second UE of the second TCI state, and communicating with the second UE in accordance with the second TCI state after transmission of the second acknowledgement message and after the time threshold.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, communicating with the second UE in accordance with the second TCI state may include operations, features, means, or instructions for switching from communicating in accordance with the first TCI state to communicating in accordance with the second TCI state.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first UE communicates according to a TDM communication scheme.

A method for wireless communications at a first UE is described. The method may include receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications, receiving, from the first UE, an indication of a first TCI state in accordance with the limitation, and communicating with the first UE in accordance with the first TCI state.

An apparatus for wireless communications at a first UE is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications, receive, from the first UE, an indication of a first TCI state in accordance with the limitation, and communicate with the first UE in accordance with the first TCI state.

Another apparatus for wireless communications at a first UE is described. The apparatus may include means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications, means for receiving, from the first UE, an indication of a first TCI state in accordance with the limitation, and means for communicating with the first UE in accordance with the first TCI state.

A non-transitory computer-readable medium storing code for wireless communications at a first UE is described. The code may include instructions executable by a processor to receive first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications, receive, from the first UE, an indication of a first TCI state in accordance with the limitation, and communicate with the first UE in accordance with the first TCI state.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the limitation defines that only one of the first UE or the second UE may be to transmit the potential TCI state.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting, to the second UE, an indication of assistance information associated with the sidelink communications between the first UE and the second UE.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the limitation defines that all potential TCI states used during the sidelink communications may have a same time threshold for application of the potential TCI states.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting, to the second UE, an acknowledgement message associated with the indication from the second UE of first TCI state and applying the first TCI state to the sidelink communications with the second UE after transmission of the acknowledgement message and after the time threshold.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the time threshold may be defined in the first control information as a quantity of symbols that follows receipt of an acknowledgement message responsive to transmission of the indication of the first TCI state.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting, to the second UE, a second indication of a second TCI state, receiving, from the second UE, a second acknowledgement message associated with the second indication from the first UE of the second TCI state, and communicating with the second UE in accordance with the second TCI state after transmission of the second acknowledgement message and after the time threshold.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, communicating with the first UE in accordance with the second TCI state may include operations, features, means, or instructions for switching from communicating in accordance with the first TCI state to communicating in accordance with the second TCI state.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first UE communicates according to a TDM communication scheme.

A method for wireless communications at a first UE is described. The method may include transmitting, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE, receiving, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state, selecting, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state, and communicating with the second UE in accordance with the selected TCI state.

An apparatus for wireless communications at a first UE is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to transmit, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE, receive, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state, select, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state, and communicate with the second UE in accordance with the selected TCI state.

Another apparatus for wireless communications at a first UE is described. The apparatus may include means for transmitting, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE, means for receiving, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state, means for selecting, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state, and means for communicating with the second UE in accordance with the selected TCI state.

A non-transitory computer-readable medium storing code for wireless communications at a first UE is described. The code may include instructions executable by a processor to transmit, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE, receive, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state, select, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state, and communicate with the second UE in accordance with the selected TCI state.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the one or more rules define that the selected TCI state may be selected, by the first UE, based on a comparison of a first priority associated with the first UE and a second priority associated with the second UE.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting one of the first TCI state or the second TCI state as the selected TCI state may include operations, features, means, or instructions for comparing the first priority and the second priority and determining the selected TCI state from the first TCI state or the second TCI state that was transmitted by the first UE or the second UE, respectively, that corresponds with a highest priority between the first priority and the second priority.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first priority and the second priority may be based on a UE type of the first UE and the second UE, respectively.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the UE type of the highest priority may be a hub UE, a RSU, or a PLC.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first priority and the second priority may be based on a quality of channel knowledge of the first UE and the second UE, respectively.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the quality of channel knowledge may be based in part on at least one of an update frequency of a CSI-RS beam codebook or a degree of refinement of the CSI-RS beam codebook.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first priority and the second priority may be based on a TCI state command type of the first control information of the first UE and of the second control information of the second UE, respectively.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the TCI state command type of the highest priority may be a TCI state command that includes a request to set a transmit beam.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first priority and the second priority may be based on a UE role of the first UE and the second UE, respectively, in the sidelink communications.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the UE role of the highest priority may be a transmitter UE when the sidelink communications may be one-directional.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the one or more rules define that the selected TCI state may be selected, by the first UE, based on a comparison of a first timing of a first acknowledgement message received in response to the first control information indicating the first TCI state and a second timing of a second acknowledgement message transmitted in response to the second control information indicating the second TCI state.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting one of the first TCI state or the second TCI state as the selected TCI state may include operations, features, means, or instructions for comparing the first timing and the second timing and determining the selected TCI state from the first TCI state or the second TCI state that was transmitted by the first UE or the second UE, respectively, that corresponds with an earliest of the first timing and the second timing.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting one of the first TCI state or the second TCI state as the selected TCI state may include operations, features, means, or instructions for comparing the first timing and the second timing and determining the selected TCI state from the first TCI state or the second TCI state that was transmitted by the first UE or the second UE, respectively, that corresponds with a latest of the first timing and the second timing.

DETAILED DESCRIPTION

Some wireless communication systems may support sidelink communications in which two or more wireless devices, such as a first user equipment (UE) and a second UE, communicate using one or more beam pairs, where each beam pair includes a transmit beam and a receive beam. In some cases, the first UE may select a first beam, such as a receive beam, for communicating with the second UE and may transmit, to the second UE, an indication of a transmission configuration indicator (TCI) state, which may be referred to as a TCI state command, associated with a second beam, such as a transmit beam, where the first beam and the second beam are part of a beam pair. In some examples, the first UE may transmit, to the second UE, a first TCI state command indicating a first TCI state and the second UE may transmit, to the first UE, a second TCI state command indicating a second TCI state, such that an application time of the first TCI state and an application time of the second TCI state may coincide. That is, the first UE may transmit an indication of the first TCI state associated with a receive beam and the second UE may transmit an indication of the second TCI associated with a transmit beam, such that the first UE may apply the second TCI state and the second UE may apply the first TCI state simultaneously. However, in some cases, the first TCI state and the second TCI state may be incompatible (e.g., not part of a beam pair). In such cases, the UEs may be unable to communicate via the indicated TCI states.

Accordingly, techniques described herein may support methods for preventing or resolving TCI state command conflicts associated with coinciding application times. In some examples, a first UE and a second UE may receive control information indicating a limitation to transmission of TCI state commands (e.g., a potential TCI state). For example, the limitation may define that only one of the first UE or the second UE may transmit TCI state commands. In such cases, the other UE (e.g., UE restricted from transmitting TCI state commands) may transmit assistance information to aid in selection of a TCI state to be indicated via a TCI state command. In some other examples, both the first UE and the second UE may each transmit TCI state commands and the limitation may define that all TCI state commands are associated with a same time threshold for application of the TCI state commands. In such cases, application times of the TCI state commands may be unique (e.g., not coincide) due to time division multiplexing (TDM).

Additionally, or alternatively, the first UE and the second UE may receive control information indicating (e.g., may be configured with) one or more rules associated with resolving TCI state command conflicts. For example, the one or more rules may define that the UEs select a TCI state command from a set of conflicting TCI state commands based on a comparison of a priorities associated with each UE, such that the selected TCI state command is associated with a highest priority. Additionally, or alternatively, the one or more rules many define that the UEs select the TCI state command from the set of conflicting TCI state commands based on a comparison of timing associated with acknowledgement messages associated with each TCI state command. For example, each TCI state command from the set of conflicting TCI state commands may be associated with an acknowledgement message, such that the selected TCI state command is associated with an earliest received acknowledgement message. Conversely, the selected TCI state command may be associated with a latest received acknowledgement message.

Aspects of the disclosure are initially described in the context of wireless communications systems. Aspects of the disclosure are then described in the context of a timing diagram and process flows. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to sidelink TCI state command conflict resolution.

In some cases, the wireless communications system100may support techniques to avoid or resolve TCI state command confliction in sidelink communications. For example, a first UE115may be in sidelink communications with a second UE115and each UE115may receive control information that indicates a limitation to transmission of a potential TCI state, where the limitation restricts the first UE115and the second UE115from simultaneously applying different potential TCI states during the sidelink communications. In some examples, the limitation may define that only the first UE115or the second UE115is allowed to transmit the potential TCI state. Additionally, or alternatively, the limitation may define that all potential TCI states used during the sidelink communications have a same time threshold for application of the potential TCI states.

Additionally, or alternatively, the first UE115may transmit, to the second UE115, first control information that indicates a first TCI state and may receive, from the second UE115, second control information that indicates a second TCI state. Accordingly, the first UE115and the second UE115may select one of the first TCI state or the second TCI state as a selected TCI state based on one or more rules for resolving sidelink TCI state conflicts. In some examples, the one or more rules may define that the selected TCI state is selected based on a comparison of a first priority associated with the first UE115and a second priority associated with the second UE115. Additionally, or alternatively, the one or more rules may define that the selected TCI state is selected based on a comparison of first timing of a first acknowledgement message received in response to the first control information and second timing of a second acknowledgement message transmitted in response to the second control information. As such, the first UE115and the second UE115may communicate in accordance with the selected TCI state.

FIG.2illustrates an example of a wireless communications system200that supports sidelink TCI state command conflict resolution in accordance with one or more aspects of the present disclosure. In some examples, the wireless communications system200may implement or be implemented by aspects of the wireless communications system100. For example, the wireless communications system200may include one or more network entities105and one or more UEs115(e.g., a UE115-aand a UE115-b), which may be examples of the corresponding devices as described with reference toFIG.1. The wireless communications system200may include features for preventing or resolving TCI state command (e.g., TCI command) confliction as described herein.

Some wireless communication systems may support sidelink communications in which two or more wireless devices, such as a UE115-aand a UE115-b, may communicate via one or more sidelink communications links. For example, the UE115-aand the UE115-bmay communicate using one or more beam pairs220, such as a beam pair220-aand a beam pair220-b, where each beam pair220includes a transmit beam215and a receive beam215. In some cases, the UE115-amay select a beam215, such as a beam215-a(e.g., a receive beam215-a), for communicating with the UE115-band may transmit, to the UE115-b, an indication of a TCI state, which may be referred to as a TCI state command205(e.g., TCI command205), associated with a beam215-b(e.g., a transmit beam215-b), where the beam215-aand the beam215-bare part of the beam pair220-a.

Some TCI state commands205(e.g., shared separate TCI state commands205) may be applicable to either sidelink communication links (e.g., channels) used for transmitting (e.g., forward link (FL) channels) or sidelink communication links used for receiving (e.g., reverse link (RL) channels). That is, the UE115-amay transmit sidelink communications to the UE115-bvia a first channel (e.g., a FL physical sidelink shared channel (PSSCH), a FL physical sidelink control channel (PSCCH), or a FL physical sidelink feedback channel (PSFCH)) and receive sidelink communications from the UE115-bvia a second channel (e.g., a RL PSSCH, FL PSCCH, FL PSFCH), such that a TCI state command205may indicate a TCI state (e.g., shared separate FL TCI state) that may be applied to the first channel or may indicate a TCI state (e.g., shared separate RL TCI state) to be applied the second channel. Some other TCI state commands205(e.g., shared joint TCI state commands205) may be applicable to multiple channels, such as both the first channel and the second channel. That is, the UE115-amay transmit sidelink communications to the UE115-bvia the first channel and receive sidelink communications from the UE115-bvia the second channel, such that a TCI state command205may indicate a TCI state that may be applied to both the first channel and the second channel. The UE115-a, the UE115-b, or both, may transmit TCI state commands205via sidelink control information (SCI) or via sidelink medium access control (MAC) control element (MAC-CE).

In some examples, the UE115-amay select the beam215-a(e.g., the receive beam215-a) for communicating with the UE115-band may transmit a TCI state command205-aindicating a TCI state associated with the beam215-b(e.g., the transmit beam215-b) for the UE115-bto use to communicate with the UE115-a. Additionally, the UE115-bmay select a beam215-d(e.g., a transmit beam) for communicating with the UE115-aand may transmit a TCI state command205-bindicating a TCI state associated with a beam215-c(e.g., a receive beam215-c) for the UE115-ato use to communicate with the UE115-b. In such cases, the UE115-amay transmit the TCI state command205-aand the UE115-bmay transmit the TCI state command205-bwithin a duration, such that an application time of the TCI state command205-aand an application time of the TCI state command205-bmay coincide (e.g., may be simultaneous, may overlap in the time domain. That is, the UE115-bmay transmit an acknowledgement message210-ain response to the TCI state command205-aand may apply the TCI state indicated via the TCI state command205-a(e.g., apply the TCI state command205-a) based on transmitting the acknowledgement message210-a. Similarly, the UE115-amay transmit an acknowledgement message210-bin response to the TCI state command205-band may apply the TCI state indicated via the TCI state command205-b(e.g., apply the TCI state command205-b) based on transmitting the acknowledgement message210-b. In such cases, a time at which the UE115-aapplies the TCI state command205-b(e.g., the application time of the TCI state command205-b) may coincide (e.g., be simultaneous) with a time that the UE115-bapplies the TCI state command205-a(e.g., the application time of the TCI state command205-a).

In some examples (e.g., if a TCI state command205is transmitted via MAC-CE), the UE115-a, the UE115-b, or both, may apply a TCI state command205a configured (e.g., preconfigured) threshold of time (e.g., 3 ms) after an acknowledgement message210associated with the TCI state command205is received. In some other examples (e.g., if a TCI state command205is transmitted via SCI), the UE115-a, the UE115-b, or both, may apply a TCI state command205a configured (e.g., preconfigured) quantity (e.g., number) of symbols (e.g., Y symbols) after an acknowledgement message210associated with the TCI state command205is received.

However, in some cases, the beam215-b(e.g., transmit beam215-b) associated with (e.g., indicated via) the TCI state command205-aand the beam215-c(e.g., receive beam215-c) associated with the TCI state command205-bmay be incompatible (e.g., not part of a beam pair220). That is, the beam215-bmay be part of the beam pair220-aand the beam215-cmay be part of the beam pair220-b. In other words, the TCI state command205-aand the TCI state command205-bmay be conflicting TCI state commands205. In such cases, the UE115-aand the UE115-bmay be unable to communicate via the TCI states (e.g., beams215) indicated via the conflicting TCI state commands205(e.g., due to the coinciding application times).

Accordingly, techniques described herein may support avoiding (e.g., preventing) or resolving transmission of conflicting TCI state commands205(e.g., with coinciding application times). In some implementations, a first UE, such as a UE115-a, and a second UE, such as a UE115-b, may receive (e.g., from a network entity105, another UE115, etc.) control information indicating a limitation that restricts the UE115-aand the UE115-bfrom simultaneously applying different potential TCI states associated with conflicting TCI state commands205during sidelink communications.

In some cases, the limitation may define that only one of the UE115-aor the UE115-bis to transmit (e.g., is allowed to transmit) TCI state commands205(e.g., indications of potential TCI states). For example, the UE115-amay receive the control information indicating that the UE115-amay transmit TCI state commands205, such that the UE115-amay transmit a TCI state command205-ato the UE115-b. Additionally, or alternatively, the UE115-bmay receive the control information indicating that the UE115-bis restricted from transmitting TCI state commands205, such that the UE115-bmay refrain from transmitting a TCI state command205-b. In such cases, the UE115-bmay transmit assistance information, reports, or both, to the UE115-ato support the UE115-adetermining the TCI state command205-a. That is, the assistance information, reports, or both, may indicate information associated with communications of the UE115-b, such as channel quality, beam reports, interference, or the like thereof, such that the UE115-amay select a beam pair220, such as a beam pair220-a, for communicating with the UE115-b. Accordingly, the UE115-amay transmit the TCI state command205-aindicating the beam215-b(e.g., indicating the TCI state associated with the beam215-b), such that the UE115-aand the UE115-bmay communicate via the beam pair220-a. In some cases, the UE115configured to (e.g., enabled to, permitted to, allowed to) transmit TCI state commands205may be, for example, a roadside unit (RSU) (e.g., for vehicle-to-everything (V2X) purposes) or a programmable logic controller (PLC) (e.g., for industrial internet of things (IIoT). purposes).

Additionally, or alternatively, the limitation may define that all TCI state commands205may be associated with a same time threshold for application of the TCI state commands205. In other words, all potential TCI states indicated via TCI state commands205may have a same time threshold for application of the potential TCI states. For example, the time threshold (e.g., indicated via the control information) may be a quantity of symbols (e.g., Y symbols) that follows receipt of an acknowledgement message responsive to transmission of a TCI state command205. As such, the UE115-aand the UE115-bmay transmit (e.g., at different times) the TCI state command205-aand the TCI state command205-b, respectively, and may apply the TCI state commands205(e.g., at different times) based on receiving the acknowledgement message210-aand the acknowledgement message210-b, respectively. Thus, the UEs115may apply the TCI state commands205at different times (e.g., due to the TDM nature), avoiding conflict between the TCI state commands205, described with reference toFIG.3.

Additionally, or alternatively, the UEs115-aand115-bmay receive (e.g., from a network entity105, another UE115, etc.) an indication of a one or more rules for resolving conflicting TCI state commands205, such as the TCI state command205-aand the TCI state command205-b. For example, the UE115-amay transmit the TCI state command205-aindicating the beam215-b(e.g., indicating a TCI state associated with the beam215-b) and the UE115-bmay transmit the TCI state command205-bindicating the beam215-c(e.g., indicating a TCI state associated with the beam215-c), such that the application time of the TCI state command205-acoincides with the application time of the TCI state command205-b, resulting the TCI state command205-aconflicting with the TCI state command205-b. Accordingly, the UE115-a, the UE115-b, or both, may select one of the TCI state command205-a(e.g., the TCI state indicated via the TCI state command205-a) or the TCI state command205-b(e.g., the TCI state indicated via the TCI state command205-b) based on the one or more rules for resolving conflicting TCI state commands205. As such, the UE115-a, the UE15-b, or both, may apply the selected TCI state command205and communicate in accordance with the selected TCI state (e.g., associated with the selected TCI state command205)

In some examples, a first rule of the one or more rules may define that the selected TCI state is selected (e.g., by the UE115-a, the UE115-b, or both) based on a comparison of a first priority associated with the UE115-aand a second priority associated with the UE115-b. That is, the UE115-a, the UE115-b, or both, may compare the first priority and the second priority and may determine the selected TCI state command205from the TCI state command205-aor the TCI state command205-bbased on the UE115associated with a highest priority between the first priority or the second priority. For example, the first priority may be higher than the second priority, such that the UEs115select (e.g., and apply) the TCI state command205-a, such that the UEs115may communicate via the beam pair220-a(e.g., the beam215-aand the beam215-b).

In some cases (e.g., start topology), the first priority and the second priority may be based on a UE115type of the UE115-aand the UE115-b, respectively. In such cases, the UE115type of the highest priority may be a hub UE115, (e.g., hub sidelink UE115), a RSU (e.g., in V2X), or a PLC (e.g., in IIoT). Additionally, or alternatively, the first priority and the second priority are based on a quality of channel knowledge of the UE115-aand the UE115-b, respectively. In such cases, the UE115associated with the highest priority may be associated with the highest quality of channel knowledge. That is, the quality of channel knowledge may be based on at least one of an update frequency of a channel state information reference signal (CSI-RS) beam codebook or a degree of refinement of the CSI-RS beam codebook, such that the UE115associated with the highest priority may receive a more frequent or refined CSI-RS beam codebook. Additionally, or alternatively, the first priority and the second priority may be based on a TCI state command205type of the TCI state command205-aand the TCI state command205-b, respectively. In such cases, the TCI state command type of the highest priority may be a TCI state command205that includes a request to set a transmit beam215(e.g., compared to a TCI state command205that includes a request to set a receive beam215). Additionally, or alternatively, the first priority and the second priority may be based on a UE115role of the UE115-aand the UE115-b, respectively. In such cases, the UE115role of the highest priority may be a transmitter UE115(e.g., when the sidelink communications are one-directional).

Additionally, or alternatively, a second rule of the one or more rules may define that the selected TCI state is selected (e.g., by the UE115-a, the UE115-b, or both) based on a comparison of timing associated with reception of acknowledgement messages210associated with the TCI state commands205. That is, the UE115-a, the UE115-b, or both, may compare first timing associated with the acknowledgement message210-areceived in response to the TCI state command205-aand second timing associated with the acknowledgement message210-breceived in response to the TCI state command205-b. In some examples, the second rule may indicate to select the TCI state command205associated with an earliest received acknowledgement message210. For example, the UE115-bmay apply the TCI state command205-abased on the UE115-areceiving the acknowledgement message210-aassociated with the TCI state command205-abefore the UE115-breceives the acknowledgement message210-bassociated with the TCI state command205-b(e.g., based on the first timing being before the second timing). In some other examples, the second rule may indicate to select the TCI state command205associated with a latest (e.g., last) received acknowledgement message210. For example, the UE115-amay apply the TCI state command205-bbased on the UE115-breceiving the acknowledgement message210-bassociated with the TCI state command205-bafter the UE115-areceives the acknowledgement message210-aassociated with the TCI state command205-b(e.g., based on the second timing being after the first timing).

In other words, the second rule of the one or more rules may indicate for the UE115-aand the UE115-bto apply a TCI state command205based on the order of slots during which the acknowledgement message210-aand the acknowledgement message210-bare communicated. For example, the second rule of the one or more rules may indicate for the UE115-aand the UE115-bto select the TCI state associated with the TCI state command205-abased on the UE115-areceiving an acknowledgement message210-aassociated with the TCI state command205-aduring a first slot which occurs before a second slot during which the UE115-breceives an acknowledgement message210-bassociated with the TCI state command205-b. Conversely, the second rule of the one or more rules may indicate for the UE115-aand the UE115-bto select the TCI state associated with the TCI state command205-bbased on the UE115-breceiving the acknowledgement message210-bassociated with the TCI state command205-bduring the second slot which occurs after the first slot during which the UE115-areceives the acknowledgement message210-aassociated with the TCI state command205-a.

FIG.3illustrates an example of a timing diagram300that supports sidelink TCI state command conflict resolution in accordance with one or more aspects of the present disclosure. In some examples, the timing diagram300may implement or be implemented by aspects of the wireless communications system100or the wireless communications system200. For example, the timing diagram300may include one or more network entities105and one or more UEs115(e.g., a UE115-cand a UE115-d), which may be examples of the corresponding devices as described with reference toFIG.1. The timing diagram300may include features for preventing or resolving TCI state command confliction as described herein.

In some examples, a UE115-cand a UE115-dmay transmit a TCI state command305-aand a TCI state command305-brespectively. In some examples, the TCI state command305-amay indicate for the UE115-dto communicate via a receive beam (e.g., associated with a first TCI state) and the TCI state command305-bmay indicate for the UE115-cto communicate via a transmit beam (e.g., associated with a second TCI state). In some cases, the receive beam and the transmit beam may be incompatible (e.g., not part of a beam pair) and an application time315associated with the receive beam may coincide with an application time associated with the transmit beam. In other words, the TCI state command305-aand the TCI state command305-bmay be conflicting TCI state commands305(e.g., the first TCI state and the second TCI state may conflict).

According, as described with reference toFIG.2, the UE115-cand the UE115-dmay receive control information indicating a limitation that restricts the UE115-cand the UE115-dfrom simultaneously applying different TCI state commands305(e.g., potential TCI states) during the sidelink communications. Additionally, the limitation may define that all TCI state commands305(e.g., all potential TCI states) used during sidelink communications may have a same time threshold for application of the TCI state commands305. In such cases, the time threshold may be a quantity of symbols (e.g., preconfigure quantity of symbols) after receipt of an acknowledgement message310(e.g., ACK310) in response to a TCI state command305. In some examples, the UEs115may receive the indication of the limitation (e.g., an indication of the time threshold) via an RRC message.

For example, the UE115-cmay transmit, to the UE115-d, the TCI state command305-aat a first time and the UE115-dmay transmit, to the UE115-c, the TCI state command305-bat a second time, where the TCI state command305-aand the TCI state command305-bconflict (e.g., indicate beams that are not part of a beam pair). Additionally, the UE115-cmay receive, from the UE115-d, an acknowledgement message310-a(e.g., ACK310-a) in response to the TCI state command305-a(e.g., at a third time). As such, the UEs115may apply the TCI state command305-a(e.g., may begin communicating via the TCI state indicated via the TCI state command305-a) at an application time315-a, which may be a time320(e.g., the quantity of symbols) after the UE115-creceives the acknowledgement message310-a, where the time320is based on the time threshold indicated via the limitation. Additionally, the UE115-dmay receive, from the UE115-c, an acknowledgement message310-b(e.g., ACK310-b) in response to the TCI state command305-b(e.g., at a fourth time). As such, the UEs115may apply the TCI state command305-b(e.g., may begin communicating via the TCI state indicated via the TCI state command305-b) at an application time315-b, which may be the time320after the UE115-dreceives the acknowledgement message310-b. In other words, the UE115-cand the UE115-dmay communicate via a beam pair (e.g., TCI state) associated with the TCI state command305-afrom the application time315-auntil the application time315-band may switch to communicating via a beam pair associated with the TCI state command305-bthe time320after the UE115-dreceives the acknowledgement message310-b(e.g., at the application time315-b). In other words, the UE115-cand the UE115-dmay communicate according to a TDM communication scheme, such that the first time, the second time, the third time, and the fourth time may all be different (e.g., which may prevent coinciding application times315).

FIG.4illustrates an example of a process flow400that supports sidelink TCI state command conflict resolution in accordance with one or more aspects of the present disclosure. In some examples, the process flow400may implement or be implemented by aspects of the wireless communications system100, the wireless communications system200, and the timing diagram300. For example, the process flow400may include one or more network entities105(e.g., a network entity105-a) and one or more UEs115(e.g., a UE115-eand a UE115-f), which may be examples of the corresponding devices as described with reference toFIG.1. The process flow400may include features for preventing TCI state command confliction as described herein.

At405, the UE115-e, the UE115-f, or both, may receive (e.g., from the network entity105-a, the UE115-e, the UE115-f, or another UE115) first control information that is indicative of a limitation to transmission, by a sidelink UE115, of a potential TCI state. The limitation may restrict the UE115-eand the UE115-f(e.g., in sidelink communications with the UE115-e) from simultaneously applying different potential TCI states during the sidelink communications.

In some cases, the limitation may define that only one of the UE115-eor the UE115-fis to transmit the potential TCI state. In some examples, the limitation may define that only one of the UE115-eor the UE115-fis to transmit the potential TCI state based on a designated UE115type of the UE115-eor the UE115-f. That is, the designated UE115type may be representative of UEs115allowed to transmit the potential TCI state in accordance with the limitation. In some cases, the designated UE115type may be an RSU or a PLC.

Additionally, or alternatively, the limitation may define that all potential TCI states used during the sidelink communications have a same time threshold for application of the potential TCI states. In some cases, the time threshold may define a quantity of symbols that follows receipt of an acknowledgement message responsive to transmission of an indication of a TCI state.

In some cases, at410, the UE115-emay receive, from the UE115-f, an indication of assistance information associated with the sidelink communications between the UE115-eand the UE115-f(e.g., based on the limitation may defining that only the UE115-eis to transmit the potential TCI state).

At415, the UE115-emay transmit, to the UE115-f, an indication of a first TCI state in accordance with the limitation. For example, the limitation may define that only the UE115-eis to transmit the potential TCI state. That is, the UE115-fmay determine that a type of the UE115-ematches a designated UE115type specified by the limitation. In some examples, the UE115-emay determine the first TCI state based on the assistance information.

In some cases, at420, the UE115-emay receive, from the UE115-f, an indication of a second TCI state in accordance with the limitation. For example, the limitation may define that only the UE115-fis to transmit the potential TCI state.

In some cases, at425, the UE115-emay receive, from the UE115-f, a first acknowledgement message in response to (e.g., associated with) the indication of the first TCI state (e.g., from the UE115-e).

In some cases, at430, the UE115-emay transmit, to the UE115-f, a second acknowledgement message in response to the indication of the second TCI state (e.g., from the UE115-f).

Accordingly, at435, the UE115-eand the UE115-fmay communicate in accordance with the first TCI state or the second TCI state (e.g., based on the limitation). For example, the UE115-eand the UE115-fmay communicate in accordance with the first TCI state. Additionally, or alternatively, the UE115-eand the UE115-fmay communicate in accordance with the second TCI state. In such cases, the UEs115may communicate according to a TDM communication scheme.

For example, the UEs115may apply the first TCI state to the sidelink communications after receipt of the first acknowledgement message and after the time threshold (e.g., the time threshold after receipt of the first acknowledgement message). Additionally, or alternatively, the UEs115may apply the second TCI state to the sidelink communications after receipt of the second acknowledgement message and after the time threshold (e.g., the time threshold after receipt of the second acknowledgement message). For example, the UEs115may switch from communicating in accordance with the first TCI state to communicating in accordance with the second TCI state.

FIG.5illustrates an example of a process flow500that supports sidelink TCI state command conflict resolution in accordance with one or more aspects of the present disclosure. In some examples, the process flow500may implement or be implemented by aspects of the wireless communications system100, the wireless communications system200, the timing diagram300, and the process flow400. For example, the process flow500may include one or more network entities105and one or more UEs115(e.g., a UE115-gand a UE115-h), which may be examples of the corresponding devices as described with reference toFIG.1. The process flow500may include features for resolving TCI state command confliction as described herein.

At505, the UE115-gmay transmit, to the UE115-h, first control information (e.g., a first TCI state command) that indicates a first TCI state for use in sidelink communications between the UE115-gand the UE115-h.

At510, the UE115-gmay receive, from the UE115-h, second control information (e.g., a second TCI state command) that indicates a second TCI state for use in sidelink communications between the UE115-gand the UE115-h. Additionally, a first application time of the first TCI state may conflict (e.g., coincide) with a second application time of the second TCI state.

In some cases, at515, the UE115-gmay receive, from the UE115-g, a first acknowledgement message in response to the first control information indicating the first TCI state.

In some cases, at520, the UE115-gmay transmit, to the UE115-g, a second acknowledgement message in response to the second control information indicating the second TCI state.

At525and530, each UE115(e.g., the UE115-g, the UE115-h, or both) may select one of the first TCI state or the second TCI state as a selected TCI state based on (e.g., in accordance with) one or more rules for resolving TCI state (e.g., sidelink TCI state) conflicts.

In some cases, the one or more rules may define that the selected TCI state is selected (e.g., by the UE115-g, the UE115-h, or both) based on a comparison of a first priority associated with the UE115-gand a second priority associated with the UE115-h. For example, each UE115(e.g., the UE115-g, the UE115-h, or both) may compare the first priority and the second priority and may determine the selected TCI state from the first TCI state or the second TCI state that corresponds with a highest priority between the first priority and the second priority.

In some cases, the first priority and the second priority may be based on a UE115type of the UE115-gand the UE115-h, respectively. For example, the UE115type of the highest priority may be a hub UE115, an RSU, or a PLC. Additionally, or alternatively, the first priority and the second priority may be based on a quality of channel knowledge of the UE115-gand the UE115-h, respectively. For example, the UE115with a higher quality of channel knowledge may be associated with a higher priority. In some examples, the quality of channel knowledge may be based on at least one of an update frequency of a CSI-RS beam codebook or a degree of refinement of the CSI-RS beam codebook. Additionally, or alternatively, the first priority and the second priority may be based on a TCI state command type of the first control information of the UE115-gand of the second control information of the UE115-h, respectively. For example, the TCI state command type of the highest priority may be a TCI state command that includes a request to set a transmit beam. Additionally, or alternatively, the first priority and the second priority may be based on a UE115role of the UE115-gand the UE115-h, respectively, in the sidelink communications. For example, the UE115role of the highest priority may be a transmitter UE115when the sidelink communications are one-directional

Additionally, or alternatively, the one or more rules may define that the selected TCI state is selected (e.g., by the UE115-g, the UE115-h, or both) based on a comparison of a first timing of the first acknowledgement message received in response to the first control information indicating the first TCI state and a second timing of the second acknowledgement message transmitted in response to the second control information indicating the second TCI state. For example, each UE115(e.g., the UE115-g, the UE115-h, or both) may compare the first timing and the second timing and may determine the selected TCI state from the first TCI state or the second TCI state that corresponds with an earliest of the first timing and the second timing. Alternatively, each UE115(e.g., the UE115-g, the UE115-h, or both) may compare the first timing and the second timing and may determine the selected TCI state from the first TCI state or the second TCI state that corresponds with a latest of the first timing and the second timing

Accordingly, at535, the UE115-gand the UE115-hmay communicate in accordance with the selected TCI state.

FIG.6illustrates a block diagram600of a device605that supports sidelink TCI state command conflict resolution in accordance with one or more aspects of the present disclosure. The device605may be an example of aspects of a UE115as described herein. The device605may include a receiver610, a transmitter615, and a communications manager620. The device605may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The communications manager620, the receiver610, the transmitter615, or various combinations thereof or various components thereof may be examples of means for performing various aspects of sidelink TCI state command conflict resolution as described herein. For example, the communications manager620, the receiver610, the transmitter615, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

In some examples, the communications manager620may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver610, the transmitter615, or both. For example, the communications manager620may receive information from the receiver610, send information to the transmitter615, or be integrated in combination with the receiver610, the transmitter615, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager620may support wireless communications at a first UE in accordance with examples as disclosed herein. For example, the communications manager620may be configured as or otherwise support a means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. The communications manager620may be configured as or otherwise support a means for transmitting, to the second UE, an indication of a first TCI state in accordance with the limitation. The communications manager620may be configured as or otherwise support a means for communicating with the second UE in accordance with the first TCI state.

Additionally, or alternatively, the communications manager620may support wireless communications at a first UE in accordance with examples as disclosed herein. For example, the communications manager620may be configured as or otherwise support a means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. The communications manager620may be configured as or otherwise support a means for receiving, from the first UE, an indication of a first TCI state in accordance with the limitation. The communications manager620may be configured as or otherwise support a means for communicating with the first UE in accordance with the first TCI state.

Additionally, or alternatively, the communications manager620may support wireless communications at a first UE in accordance with examples as disclosed herein. For example, the communications manager620may be configured as or otherwise support a means for transmitting, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE. The communications manager620may be configured as or otherwise support a means for receiving, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state. The communications manager620may be configured as or otherwise support a means for selecting, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state. The communications manager620may be configured as or otherwise support a means for communicating with the second UE in accordance with the selected TCI state.

By including or configuring the communications manager620in accordance with examples as described herein, the device605(e.g., a processor controlling or otherwise coupled with the receiver610, the transmitter615, the communications manager620, or a combination thereof) may support techniques for TCI state command conflict resolution in sidelink communications which may result in reduced processing, reduced power consumption, and more efficient utilization of communication resources, among other advantages.

FIG.7illustrates a block diagram700of a device705that supports sidelink TCI state command conflict resolution in accordance with one or more aspects of the present disclosure. The device705may be an example of aspects of a device605or a UE115as described herein. The device705may include a receiver710, a transmitter715, and a communications manager720. The device705may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The device705, or various components thereof, may be an example of means for performing various aspects of sidelink TCI state command conflict resolution as described herein. For example, the communications manager720may include a restriction component725, a TCI state component730, a selection component735, or any combination thereof. The communications manager720may be an example of aspects of a communications manager620as described herein. In some examples, the communications manager720, or various components thereof, may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver710, the transmitter715, or both. For example, the communications manager720may receive information from the receiver710, send information to the transmitter715, or be integrated in combination with the receiver710, the transmitter715, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager720may support wireless communications at a first UE in accordance with examples as disclosed herein. The restriction component725may be configured as or otherwise support a means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. The TCI state component730may be configured as or otherwise support a means for transmitting, to the second UE, an indication of a first TCI state in accordance with the limitation. The TCI state component730may be configured as or otherwise support a means for communicating with the second UE in accordance with the first TCI state.

Additionally, or alternatively, the communications manager720may support wireless communications at a first UE in accordance with examples as disclosed herein. The restriction component725may be configured as or otherwise support a means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. The TCI state component730may be configured as or otherwise support a means for receiving, from the first UE, an indication of a first TCI state in accordance with the limitation. The TCI state component730may be configured as or otherwise support a means for communicating with the first UE in accordance with the first TCI state.

Additionally, or alternatively, the communications manager720may support wireless communications at a first UE in accordance with examples as disclosed herein. The TCI state component730may be configured as or otherwise support a means for transmitting, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE. The TCI state component730may be configured as or otherwise support a means for receiving, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state. The selection component735may be configured as or otherwise support a means for selecting, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state. The TCI state component730may be configured as or otherwise support a means for communicating with the second UE in accordance with the selected TCI state.

FIG.8illustrates a block diagram800of a communications manager820that supports sidelink TCI state command conflict resolution in accordance with one or more aspects of the present disclosure. The communications manager820may be an example of aspects of a communications manager620, a communications manager720, or both, as described herein. The communications manager820, or various components thereof, may be an example of means for performing various aspects of sidelink TCI state command conflict resolution as described herein. For example, the communications manager820may include a restriction component825, a TCI state component830, a selection component835, an assistance information component840, a feedback component845, a priority component850, a timing component855, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses).

The communications manager820may support wireless communications at a first UE in accordance with examples as disclosed herein. The restriction component825may be configured as or otherwise support a means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. The TCI state component830may be configured as or otherwise support a means for transmitting, to the second UE, an indication of a first TCI state in accordance with the limitation. In some examples, the TCI state component830may be configured as or otherwise support a means for communicating with the second UE in accordance with the first TCI state.

In some examples, the limitation defines that only one of the first UE or the second UE is to transmit the potential TCI state.

In some examples, the assistance information component840may be configured as or otherwise support a means for receiving, from the second UE, an indication of assistance information associated with the sidelink communications between the first UE and the second UE. In some examples, the TCI state component830may be configured as or otherwise support a means for determining the first TCI state based on the assistance information.

In some examples, the restriction component825may be configured as or otherwise support a means for determining that a type of the first UE matches a designated UE type specified by the limitation, the designated UE type representative of UEs allowed to transmit the potential TCI state in accordance with the limitation.

In some examples, the designated UE type is a RSU or a PLC.

In some examples, the limitation defines that all potential TCI states used during the sidelink communications have a same time threshold for application of the potential TCI states.

In some examples, the feedback component845may be configured as or otherwise support a means for receiving, from the second UE, an acknowledgement message associated with the indication from the first UE of the first TCI state. In some examples, the TCI state component830may be configured as or otherwise support a means for applying the first TCI state to the sidelink communications with the second UE after receipt of the acknowledgement message and after the time threshold.

In some examples, the time threshold is defined in the first control information as a quantity of symbols that follows receipt of an acknowledgement message responsive to transmission of the indication of the first TCI state.

In some examples, the TCI state component830may be configured as or otherwise support a means for receiving, from the second UE, a second indication of a second TCI state. In some examples, the feedback component845may be configured as or otherwise support a means for transmitting, to the second UE, a second acknowledgement message associated with the second indication from the second UE of the second TCI state. In some examples, the TCI state component830may be configured as or otherwise support a means for communicating with the second UE in accordance with the second TCI state after transmission of the second acknowledgement message and after the time threshold.

In some examples, to support communicating with the second UE in accordance with the second TCI state, the TCI state component830may be configured as or otherwise support a means for switching from communicating in accordance with the first TCI state to communicating in accordance with the second TCI state.

In some examples, the first UE communicates according to a time division multiplexing communication scheme.

Additionally, or alternatively, the communications manager820may support wireless communications at a first UE in accordance with examples as disclosed herein. In some examples, the restriction component825may be configured as or otherwise support a means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. In some examples, the TCI state component830may be configured as or otherwise support a means for receiving, from the first UE, an indication of a first TCI state in accordance with the limitation. In some examples, the TCI state component830may be configured as or otherwise support a means for communicating with the first UE in accordance with the first TCI state.

In some examples, the limitation defines that only one of the first UE or the second UE is to transmit the potential TCI state.

In some examples, the assistance information component840may be configured as or otherwise support a means for transmitting, to the second UE, an indication of assistance information associated with the sidelink communications between the first UE and the second UE.

In some examples, the limitation defines that all potential TCI states used during the sidelink communications have a same time threshold for application of the potential TCI states.

In some examples, the feedback component845may be configured as or otherwise support a means for transmitting, to the second UE, an acknowledgement message associated with the indication from the second UE of first TCI state. In some examples, the TCI state component830may be configured as or otherwise support a means for applying the first TCI state to the sidelink communications with the second UE after transmission of the acknowledgement message and after the time threshold.

In some examples, the time threshold is defined in the first control information as a quantity of symbols that follows receipt of an acknowledgement message responsive to transmission of the indication of the first TCI state.

In some examples, the TCI state component830may be configured as or otherwise support a means for transmitting, to the second UE, a second indication of a second TCI state. In some examples, the feedback component845may be configured as or otherwise support a means for receiving, from the second UE, a second acknowledgement message associated with the second indication from the first UE of the second TCI state. In some examples, the TCI state component830may be configured as or otherwise support a means for communicating with the second UE in accordance with the second TCI state after transmission of the second acknowledgement message and after the time threshold.

In some examples, to support communicating with the first UE in accordance with the second TCI state, the TCI state component830may be configured as or otherwise support a means for switching from communicating in accordance with the first TCI state to communicating in accordance with the second TCI state.

In some examples, the first UE communicates according to a time division multiplexing communication scheme.

Additionally, or alternatively, the communications manager820may support wireless communications at a first UE in accordance with examples as disclosed herein. In some examples, the TCI state component830may be configured as or otherwise support a means for transmitting, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE. In some examples, the TCI state component830may be configured as or otherwise support a means for receiving, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state. The selection component835may be configured as or otherwise support a means for selecting, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state. In some examples, the TCI state component830may be configured as or otherwise support a means for communicating with the second UE in accordance with the selected TCI state.

In some examples, the one or more rules define that the selected TCI state is selected, by the first UE, based on a comparison of a first priority associated with the first UE and a second priority associated with the second UE.

In some examples, to support selecting one of the first TCI state or the second TCI state as the selected TCI state, the priority component850may be configured as or otherwise support a means for comparing the first priority and the second priority. In some examples, to support selecting one of the first TCI state or the second TCI state as the selected TCI state, the selection component835may be configured as or otherwise support a means for determining the selected TCI state from the first TCI state or the second TCI state that was transmitted by the first UE or the second UE, respectively, that corresponds with a highest priority between the first priority and the second priority.

In some examples, the first priority and the second priority are based on a UE type of the first UE and the second UE, respectively.

In some examples, the UE type of the highest priority is a hub UE, a RSU, or a PLC.

In some examples, the first priority and the second priority are based on a quality of channel knowledge of the first UE and the second UE, respectively.

In some examples, the quality of channel knowledge is based in part on at least one of an update frequency of a CSI-RS beam codebook or a degree of refinement of the CSI-RS beam codebook.

In some examples, the first priority and the second priority are based on a TCI state command type of the first control information of the first UE and of the second control information of the second UE, respectively.

In some examples, the TCI state command type of the highest priority is a TCI state command that includes a request to set a transmit beam.

In some examples, the first priority and the second priority are based on a UE role of the first UE and the second UE, respectively, in the sidelink communications.

In some examples, the UE role of the highest priority is a transmitter UE when the sidelink communications are one-directional.

In some examples, the one or more rules define that the selected TCI state is selected, by the first UE, based on a comparison of a first timing of a first acknowledgement message received in response to the first control information indicating the first TCI state and a second timing of a second acknowledgement message transmitted in response to the second control information indicating the second TCI state.

In some examples, to support selecting one of the first TCI state or the second TCI state as the selected TCI state, the timing component855may be configured as or otherwise support a means for comparing the first timing and the second timing. In some examples, to support selecting one of the first TCI state or the second TCI state as the selected TCI state, the selection component835may be configured as or otherwise support a means for determining the selected TCI state from the first TCI state or the second TCI state that was transmitted by the first UE or the second UE, respectively, that corresponds with an earliest of the first timing and the second timing.

In some examples, to support selecting one of the first TCI state or the second TCI state as the selected TCI state, the timing component855may be configured as or otherwise support a means for comparing the first timing and the second timing. In some examples, to support selecting one of the first TCI state or the second TCI state as the selected TCI state, the selection component835may be configured as or otherwise support a means for determining the selected TCI state from the first TCI state or the second TCI state that was transmitted by the first UE or the second UE, respectively, that corresponds with a latest of the first timing and the second timing.

The communications manager920may support wireless communications at a first UE in accordance with examples as disclosed herein. For example, the communications manager920may be configured as or otherwise support a means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. The communications manager920may be configured as or otherwise support a means for transmitting, to the second UE, an indication of a first TCI state in accordance with the limitation. The communications manager920may be configured as or otherwise support a means for communicating with the second UE in accordance with the first TCI state.

Additionally, or alternatively, the communications manager920may support wireless communications at a first UE in accordance with examples as disclosed herein. For example, the communications manager920may be configured as or otherwise support a means for receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. The communications manager920may be configured as or otherwise support a means for receiving, from the first UE, an indication of a first TCI state in accordance with the limitation. The communications manager920may be configured as or otherwise support a means for communicating with the first UE in accordance with the first TCI state.

Additionally, or alternatively, the communications manager920may support wireless communications at a first UE in accordance with examples as disclosed herein. For example, the communications manager920may be configured as or otherwise support a means for transmitting, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE. The communications manager920may be configured as or otherwise support a means for receiving, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state. The communications manager920may be configured as or otherwise support a means for selecting, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state. The communications manager920may be configured as or otherwise support a means for communicating with the second UE in accordance with the selected TCI state.

By including or configuring the communications manager920in accordance with examples as described herein, the device905may support techniques for TCI state command conflict resolution in sidelink communications which may result in improved communication reliability, reduced latency, improved user experience related to reduced processing, reduced power consumption, more efficient utilization of communication resources, improved coordination between devices, longer battery life, and improved utilization of processing capability, among other advantages.

At1005, the method may include receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. The operations of1005may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1005may be performed by a restriction component825as described with reference toFIG.8.

At1010, the method may include transmitting, to the second UE, an indication of a first TCI state in accordance with the limitation. The operations of1010may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1010may be performed by a TCI state component830as described with reference toFIG.8.

At1015, the method may include communicating with the second UE in accordance with the first TCI state. The operations of1015may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1015may be performed by a TCI state component830as described with reference toFIG.8.

At1105, the method may include receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, where the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential TCI states during the sidelink communications. The operations of1105may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1105may be performed by a restriction component825as described with reference toFIG.8.

At1110, the method may include receiving, from the first UE, an indication of a first TCI state in accordance with the limitation. The operations of1110may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1110may be performed by a TCI state component830as described with reference toFIG.8.

At1115, the method may include communicating with the first UE in accordance with the first TCI state. The operations of1115may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1115may be performed by a TCI state component830as described with reference toFIG.8.

FIG.12illustrates a flowchart showing a method1200that supports sidelink TCI state command conflict resolution in accordance with one or more aspects of the present disclosure. The operations of the method1200may be implemented by a UE or its components as described herein. For example, the operations of the method1200may be performed by a UE115as described with reference toFIGS.1through9. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally, or alternatively, the UE may perform aspects of the described functions using special-purpose hardware.

At1205, the method may include transmitting, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE. The operations of1205may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1205may be performed by a TCI state component830as described with reference toFIG.8.

At1210, the method may include receiving, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, where a first application time of the first TCI state conflicts with a second application time of the second TCI state. The operations of1210may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1210may be performed by a TCI state component830as described with reference toFIG.8.

At1215, the method may include selecting, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state. The operations of1215may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1215may be performed by a selection component835as described with reference toFIG.8.

At1220, the method may include communicating with the second UE in accordance with the selected TCI state. The operations of1220may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1220may be performed by a TCI state component830as described with reference toFIG.8.

Aspect 1: A method for wireless communications at a first UE, comprising: receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, wherein the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications; transmitting, to the second UE, an indication of a first TCI state in accordance with the limitation; and communicating with the second UE in accordance with the first TCI state.

Aspect 2: The method of aspect 1, wherein the limitation defines that only one of the first UE or the second UE is to transmit the potential TCI state.

Aspect 3: The method of aspect 2, further comprising: receiving, from the second UE, an indication of assistance information associated with the sidelink communications between the first UE and the second UE; and determining the first TCI state based at least in part on the assistance information.

Aspect 4: The method of any of aspects 2 through 3, further comprising: determining that a type of the first UE matches a designated UE type specified by the limitation, the designated UE type representative of UEs allowed to transmit the potential TCI state in accordance with the limitation.

Aspect 5: The method of aspect 4, wherein the designated UE type is a RSU or a PLC.

Aspect 6: The method of aspect 1, wherein the limitation defines that all potential TCI states used during the sidelink communications have a same time threshold for application of the potential TCI states.

Aspect 7: The method of aspect 6, further comprising: receiving, from the second UE, an acknowledgement message associated with the indication from the first UE of the first TCI state; and applying the first TCI state to the sidelink communications with the second UE after receipt of the acknowledgement message and after the time threshold.

Aspect 8: The method of any of aspects 6 through 7, wherein the time threshold is defined in the first control information as a quantity of symbols that follows receipt of an acknowledgement message responsive to transmission of the indication of the first TCI state.

Aspect 9: The method of any of aspects 6 through 8, further comprising: receiving, from the second UE, a second indication of a second TCI state; transmitting, to the second UE, a second acknowledgement message associated with the second indication from the second UE of the second TCI state; and communicating with the second UE in accordance with the second TCI state after transmission of the second acknowledgement message and after the time threshold.

Aspect 10: The method of aspect 9, wherein communicating with the second UE in accordance with the second TCI state comprises: switching from communicating in accordance with the first TCI state to communicating in accordance with the second TCI state.

Aspect 11: The method of any of aspects 6 through 10, wherein the first UE communicates according to a TDM communication scheme.

Aspect 12: A method for wireless communications at a first UE, comprising: receiving first control information that is indicative of a limitation to transmission, by a sidelink UE, of a potential TCI state, wherein the limitation restricts the first UE and a second UE in sidelink communications with the first UE from simultaneously applying different potential transmission configuration states during the sidelink communications; receiving, from the first UE, an indication of a first TCI state in accordance with the limitation; and communicating with the first UE in accordance with the first TCI state.

Aspect 13: The method of aspect 12, wherein the limitation defines that only one of the first UE or the second UE is to transmit the potential TCI state.

Aspect 14: The method of aspect 13, further comprising: transmitting, to the second UE, an indication of assistance information associated with the sidelink communications between the first UE and the second UE.

Aspect 15: The method of aspect 12, wherein the limitation defines that all potential TCI states used during the sidelink communications have a same time threshold for application of the potential TCI states.

Aspect 16: The method of aspect 15, further comprising: transmitting, to the second UE, an acknowledgement message associated with the indication from the second UE of first TCI state; and applying the first TCI state to the sidelink communications with the second UE after transmission of the acknowledgement message and after the time threshold.

Aspect 17: The method of any of aspects 15 through 16, wherein the time threshold is defined in the first control information as a quantity of symbols that follows receipt of an acknowledgement message responsive to transmission of the indication of the first TCI state.

Aspect 18: The method of any of aspects 15 through 17, further comprising: transmitting, to the second UE, a second indication of a second TCI state; receiving, from the second UE, a second acknowledgement message associated with the second indication from the first UE of the second TCI state; and communicating with the second UE in accordance with the second TCI state after transmission of the second acknowledgement message and after the time threshold.

Aspect 19: The method of aspect 18, wherein communicating with the first UE in accordance with the second TCI state comprises: switching from communicating in accordance with the first TCI state to communicating in accordance with the second TCI state.

Aspect 20: The method of any of aspects 15 through 19, wherein the first UE communicates according to a TDM communication scheme.

Aspect 21: A method for wireless communications at a first UE, comprising: transmitting, to a second UE, first control information that indicates a first TCI state for use in sidelink communications between the first UE and the second UE; receiving, from the second UE, second control information that indicates a second TCI state for use in the sidelink communications between the first UE and the second UE, wherein a first application time of the first TCI state conflicts with a second application time of the second TCI state; selecting, in accordance with one or more rules for resolving sidelink TCI state conflicts, one of the first TCI state or the second TCI state as a selected TCI state; and communicating with the second UE in accordance with the selected TCI state.

Aspect 22: The method of aspect 21, wherein the one or more rules define that the selected TCI state is selected, by the first UE, based at least in part on a comparison of a first priority associated with the first UE and a second priority associated with the second UE.

Aspect 23: The method of aspect 22, wherein selecting one of the first TCI state or the second TCI state as the selected TCI state further comprises: comparing the first priority and the second priority; and determining the selected TCI state from the first TCI state or the second TCI state that was transmitted by the first UE or the second UE, respectively, that corresponds with a highest priority between the first priority and the second priority.

Aspect 24: The method of aspect 23, wherein the first priority and the second priority are based on a UE type of the first UE and the second UE, respectively.

Aspect 25: The method of aspect 24, wherein the UE type of the highest priority is a hub UE, a RSU, or a PLC.

Aspect 26: The method of any of aspects 23 through 25, wherein the first priority and the second priority are based on a quality of channel knowledge of the first UE and the second UE, respectively.

Aspect 27: The method of aspect 26, wherein the quality of channel knowledge is based in part on at least one of an update frequency of a CSI-RS beam codebook or a degree of refinement of the CSI-RS beam codebook.

Aspect 28: The method of any of aspects 23 through 27, wherein the first priority and the second priority are based on a TCI state command type of the first control information of the first UE and of the second control information of the second UE, respectively.

Aspect 29: The method of aspect 28, wherein the TCI state command type of the highest priority is a TCI state command that includes a request to set a transmit beam.

Aspect 30: The method of any of aspects 23 through 29, wherein the first priority and the second priority are based on a UE role of the first UE and the second UE, respectively, in the sidelink communications.

Aspect 31: The method of aspect 30, wherein the UE role of the highest priority is a transmitter UE when the sidelink communications are one-directional.

Aspect 32: The method of any of aspects 21 through 31, wherein the one or more rules define that the selected TCI state is selected, by the first UE, based at least in part on a comparison of a first timing of a first acknowledgement message received in response to the first control information indicating the first TCI state and a second timing of a second acknowledgement message transmitted in response to the second control information indicating the second TCI state.

Aspect 33: The method of aspect 32, wherein selecting one of the first TCI state or the second TCI state as the selected TCI state further comprises: comparing the first timing and the second timing; and determining the selected TCI state from the first TCI state or the second TCI state that was transmitted by the first UE or the second UE, respectively, that corresponds with an earliest of the first timing and the second timing.

Aspect 34: The method of aspect 32, wherein selecting one of the first TCI state or the second TCI state as the selected TCI state further comprises: comparing the first timing and the second timing; and determining the selected TCI state from the first TCI state or the second TCI state that was transmitted by the first UE or the second UE, respectively, that corresponds with a latest of the first timing and the second timing.

Aspect 39: An apparatus for wireless communications at a first UE, comprising at least one means for performing a method of any of aspects 12 through 20.

Aspect 42: An apparatus for wireless communications at a first UE, comprising at least one means for performing a method of any of aspects 21 through 34.