Lateral link beam management

Abstract

Methods, apparatus, and systems are disclosed for beam management for user equipment (UE) in sidelink communications. The method comprises: establishing, by a first UE, beam alignment with a second UE using a first beam; receiving a second beam assist indication indicating at least one of time information or frequency information associated with a second beam for a second UE; transmitting the second beam configuration; receiving an acknowledgement of the second beam configuration; determining whether selection of a resource is triggered, the selection of the resource being associated with use of a second beam; in response to determining that the selection of the resource is triggered, updating the candidate resource set and selecting one or more resources from the updated candidate resource set; and transmitting one or more signals or messages using one or more resources selected from the updated set of candidate resources.

Description

Cross-references to Related Patent Applications

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 445,884, filed on February 15, 2023, entitled “SIDELINK BEAM MANAGEMENT,” the entire contents of which are incorporated herein by reference. Technical Field

[0002] Apparatus and methods consistent with the present disclosure relate generally to communications, and more particularly, to methods, systems, and devices for resource selection in sidelink communications. Background Art

[0003] Sidelink communication technology enables direct communication between two or more devices (e.g., two or more vehicles in vehicle-to-everything (V2X) communication). When a transmitting device in sidelink communication uses a narrow beam to transmit data to a receiving device, the receiving device can use either a wide or narrow receive beam to receive the data. A wide receive beam can allow stable reception for the receiving device, even when one or more other devices are acting as transmitters in the sidelink communication, simultaneously transmitting data to the receiving device. However, continuous use of a wide receive beam may be impractical, particularly for high-frequency radio signals that require a focused narrow beam to compensate for high path loss. On the other hand, using a narrow receive beam can provide advantages for the receiving device, particularly in high-frequency sidelink communication. However, the beam correspondence between a narrow receive beam and a narrow transmit beam can be easily lost. Furthermore, when one or more other devices are acting as transmitters and simultaneously transmitting data to the receiving device, a narrow receive beam may not allow the receiving device to receive transmissions from multiple devices simultaneously. Systems and methods for flexible and efficient sidelink beam management are desired. Summary of the Invention

[0004] According to some embodiments of the present disclosure, a user equipment (UE) for sidelink communication is provided. The UE includes: a memory storing instructions; and a processor configured to execute the instructions stored in the memory to: establish beam alignment with a second UE using a first beam; receive a second beam assistance indication from the second UE, the second beam assistance indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive signals or data from the first UE; in response to receiving the second beam assistance indication, transmit a second beam configuration to the second UE; receive confirmation of the second beam configuration from the second UE; determine whether selection of a resource is triggered, the selection of the resource being associated with use of the second beam; in response to determining that selection of the resource is triggered, update a candidate resource set and select one or more resources from the updated candidate resource set so that the selected one or more resources are associated with use of the second beam; and transmit one or more signals or messages using the one or more resources selected from the updated candidate resource set.

[0005] According to some embodiments of the present disclosure, a second UE for sidelink communication is provided. The second UE includes: a memory storing instructions; and a processor configured to execute the instructions stored in the memory to: establish beam alignment with the first UE using a first beam; transmit a second beam assistance indication to the first UE, the second beam assistance indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive signals or data from the first UE; receive a second beam configuration from the first UE in response to transmitting the second beam assistance indication; and transmit a confirmation of the second beam configuration to the first UE.

[0006] According to some embodiments of the present disclosure, a method for beam management in sidelink communication is provided. The method includes: establishing, by a first UE in sidelink communication, beam alignment with a second UE using a first beam; receiving, from the second UE, a second beam assistance indication, the second beam assistance indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; transmitting, in response to receiving the second beam assistance indication, a second beam configuration to the second UE; receiving, from the second UE, a confirmation of the second beam configuration; determining, by the first UE, whether selection of a resource is triggered, the selection of the resource being associated with use of the second beam; in response to determining that selection of the resource is triggered, updating a candidate resource set and selecting one or more resources from the updated candidate resource set, so that the selected one or more resources are associated with use of the second beam; and transmitting, using the one or more resources selected from the updated candidate resource set, one or more signals or messages.

[0007] According to some embodiments of the present disclosure, a method for beam management in sidelink communication is provided. The method includes: establishing, by a second UE in sidelink communication, beam alignment with a first UE using a first beam; transmitting, to the first UE, a second beam assistance indication, the second beam assistance indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; receiving, in response to transmitting the second beam assistance indication, a second beam configuration from the first UE; and transmitting, to the first UE, a confirmation of the second beam configuration.

[0008] According to some embodiments of the present disclosure, a non-transitory computer-readable medium is provided, the non-transitory computer-readable medium storing instructions that can be executed by one or more processors of a UE in sidelink communication to perform a method. The method includes: establishing, by the first UE, beam alignment with a second UE using a first beam for the sidelink communication; receiving a second beam assistance indication from the second UE, the second beam assistance indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive signals or data from the first UE; transmitting a second beam configuration to the second UE in response to receiving the second beam assistance indication; receiving a confirmation of the second beam configuration from the second UE; determining, by the first UE, whether resource selection is triggered, the resource selection being associated with the use of the second beam; in response to determining that resource selection is triggered, updating a candidate resource set and selecting one or more resources from the updated candidate resource set so that the selected one or more resources are associated with the use of the second beam; and transmitting one or more signals or messages using the one or more resources selected from the updated candidate resource set.

[0009] According to some embodiments of the present disclosure, a non-transitory computer-readable medium is provided, the non-transitory computer-readable medium storing instructions, the instructions executable by one or more processors of a second UE in sidelink communication to perform a method. The method includes: establishing beam alignment with the first UE using a first beam for sidelink communication; transmitting a second beam assistance indication to the first UE, the second beam assistance indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive signals or data from the first UE; receiving a second beam configuration from the first UE in response to transmitting the second beam assistance indication; and transmitting a confirmation of the second beam configuration to the first UE. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] [ Figure 1 ] Figure 1 is a schematic diagram illustrating a first mode of resource allocation for sidelink communications consistent with some embodiments of the present disclosure.

[0011] [ Figure 2 ] Figure 2 is a schematic diagram illustrating a second mode for resource allocation in sidelink communications consistent with some embodiments of the present disclosure.

[0012] [ Figure 3A ] Figure 3A is a schematic diagram showing a time slot structure in sidelink communication.

[0013] [ Figure 3B ] Figure 3B is a schematic diagram illustrating another time slot structure in sidelink communications consistent with some embodiments of the present disclosure.

[0014] [ Figure 4 ] Figure 4 is a schematic diagram illustrating a method for beam alignment between a UE and a base station consistent with some embodiments of the present disclosure.

[0015] [ Figure 5 ] Figure 5 is a schematic diagram illustrating a method for sidelink beam alignment between two UEs in sidelink communication consistent with some embodiments of the present disclosure.

[0016] [ Figure 6 ] Figure 6 is a schematic diagram illustrating a method for configuration alignment in discontinuous reception (DRX) consistent with some embodiments of the present disclosure.

[0017] [Figure 7] Figure 7A is a schematic diagram illustrating sidelink communication between a receiver (Rx) UE using a wide beam and two transmitter (Tx) UEs using narrow beams. Figure 7B is a schematic diagram illustrating sidelink communication between an Rx UE using a narrow beam and two Tx UEs using narrow beams, consistent with some embodiments of the present disclosure.

[0018] [ Figure 8 ] Figure 8 is a schematic diagram illustrating a method for sidelink beam alignment between two UEs in sidelink communication consistent with some embodiments of the present disclosure.

[0019] [ Figure 9 ] Figure 9 is a block diagram of a UE consistent with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0020] Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings, in which like numerals in different figures represent the same or similar elements, unless otherwise indicated. The embodiments set forth in the following description of the exemplary embodiments do not represent all embodiments consistent with the present disclosure. Rather, they are merely examples of systems, devices, and methods consistent with aspects of the present disclosure as set forth in the appended claims.

[0021] Figure 1 is a schematic diagram illustrating a first mode of resource allocation for sidelink communications consistent with some embodiments of the present disclosure. Figure 1 , a communication system includes UE 102, UE 104, and base station 106. UE 102 may be a Tx UE in sidelink communication (SL), and UE 104 may be a Rx UE in sidelink communication. UE 102 and UE 104 may be any form of UE, for example, two vehicles in V2X communication. Base station 106 may be any currently existing base station (e.g., a gNodeB (gNB), such as a base station for Long Term Evolution (LTE) or New Radio (NR), or a base station for a future generation (6th generation (6G), 7th generation (7G), or any other future generation) of Radio Access Technology (RAT). UE 102 and UE 104 may communicate with each other using sidelink signals. For example, UE 102 may transmit a Physical Sidelink Control Channel (PSCCH) and / or a Physical Sidelink Shared Channel (PSSCH) to UE 104, and in response, UE 104 may transmit a feedback signal, such as a Physical Sidelink Feedback Channel (PSFCH), to UE 102. UE 102 and UE 104 may also communicate with one or more other UEs in sidelink communications.

[0022] In a first mode for resource allocation, when UE 102 has data and / or signals to transmit, UE 102 may request resources from base station 106. For example, UE 102 may transmit a signal, such as a Sidelink-Scheduling Request (SL-SR) signal, to base station 106. In some embodiments, UE 102 may transmit the SL-SR via a Sidelink-Buffer Status Report (SL-BSR) signal. The SL-BSR may be a Medium Access Control (MAC) Control Element (CE) from UE 102 to base station 106 and may carry information about the amount of data to be sent in the buffer of UE 102. In some embodiments, UE 102 may transmit the SL-SR via a Physical Uplink Control Channel (PUCCH) configured for a sidelink logical channel.

[0023] Upon receiving a signal from UE 102, base station 106 may determine resources to allocate to UE 102 and transmit a signal indicating the resource allocation to UE 102. For example, base station 106 may use dynamic sidelink grant downlink control information (DCI) to grant sidelink resources for up to three transmissions of a transport block. Base station 106 may also provide one or more configuration grants allocating periodic sidelink resources to UE 102. Similar to UE 102, UE 104 may also transmit an SL-SR to base station 106, and base station 106 may also perform resource allocation for UE 104 and transmit a signal indicating the resource allocation for UE 104.

[0024] In some embodiments, base station 106 may configure a single resource pool that spans the entire spectrum including the unavailable portion(s) for UE 102 and / or UE 104. In some embodiments, base station 106 may configure only one or more subchannels containing one or more available physical resource blocks (PRBs) for UE 102 and / or UE 104.

[0025] Figure 2is a schematic diagram illustrating a second mode for resource allocation in sidelink communications consistent with some embodiments of the present disclosure. In the second mode for resource allocation, UE 102 (and similarly, UE 104) may autonomously perform resource selection by means of a sensing process. For example, UE 102 may perform channel sensing on (one or more) configured sidelink transmission resource pools in order to obtain information about resources reserved by (one or more) other UEs. Channel sensing may be background sensing and / or any other type of full or partial sensing. Referring to Figure 2 , UE 102 may perform channel sensing in the sensing window and collect resource reservation information of (one or more) other UEs. For example, UE 102 may collect resource reservation information of (one or more) other UEs based on decoding sidelink control information (SCI) included in the sidelink signal received from (one or more) other UEs. UE 102 may decode SCI based on two stages: first stage SCI (SCI format 1-A) and second stage SCI (SCI format 2-A or 2-B) as defined in the 3rd Generation Partnership Project (3GPP) specification. Based on channel sensing, UE 102 may determine candidate resources, for example, by excluding occupied, reserved and / or unmonitored resources. As Figure 2 As shown, radio resources can be divided into resources in the time domain and resources in the frequency domain. Candidate resources in the time domain can be, for example, one or more frames, subframes, time slots, or symbols that can be selected for the next time period. In the frequency domain, candidate resources can be, for example, one or more channels or subchannels. Figure 2 For example, three available subframes or time slots in the time domain are shown among multiple subframes or time slots. Each subframe or time slot may include one or more symbols for PSCCH and one or more symbols for PSSCH. Once resource selection (or reselection) is triggered, during the selection window, UE 102 may select (one or more) resources from the available sidelink resources based on the channel sensing information.

[0026] In some embodiments, UE 102 may be configured with one of two modes (a first mode and a second mode) for resource allocation. In some embodiments, UE 102 may be configured with both modes for resource allocation. In some embodiments, UE 102 may switch back and forth between the first mode and the second mode for resource allocation.

[0027] Figure 3A 3 is a schematic diagram illustrating a time slot structure 300 in sidelink communication consistent with some embodiments of the present disclosure. The time slot 300 can be used for the first mode or the second mode of resource allocation described above. Figure 3AIn the time domain, slot 300 includes 14 Orthogonal Frequency Division Multiplexing (OFDM) symbols. Of the 14 OFDM symbols, two are used for the Demodulation Reference Signal (DMRS), one symbol (the first symbol) is used for Automatic Gain Control (AGC), one symbol (the last symbol) is used for the guard period, and the remaining symbols are used for PSCCH or PSSCH. In the frequency domain, slot 300 may include one or more subchannels, each of which consists of one or more Physical Resource Blocks (PRBs).

[0028] In some embodiments, time slot 300 is used for conventional sidelink communications based on contiguous resource blocks. In this case, in the frequency domain, a resource pool may consist of a set of contiguous subchannels, where a subchannel consists of multiple contiguous resource blocks. The total number of resource blocks within a given resource pool may be configured with a value ranging from 10 to 275. Typically, sidelink resource allocation, sensing, and resource selection operations are based on subchannels. The size of a subchannel is configurable and may take values ​​of 10, 12, 15, 20, 25, 50, 75, and 100 PRBs, and there may be from 1 to 27 configured numbers of subchannels in a given resource pool. Figure 3A , PSCCH transmission is associated with the lowest subchannel of the scheduled PSSCH, indicating that the bandwidth size of the PSCCH (in terms of the number of PRBs) is always less than or equal to the size of one subchannel. The configuration of the PSCCH is also part of the resource pool configuration and can be done, for example, by Radio Resource Control (RRC) signaling. As an example, the PSCCH can be configured or preconfigured so that in the frequency domain, it can occupy a number (e.g., 10, 12, 15, 20 or 25, ≦ subchannel size) PRBs, and in the time domain, it can occupy a number (e.g., 2 or 3) OFDM symbols configured or preconfigured by resource pool signaling (e.g., RRC signaling). The number of resources used for PSCCH in the frequency domain can be indicated as sl-FreqResourcePSCCH, and the number of resources used for PSCCH in the time domain can be indicated as sl-TimeResourcePSCCH.

[0029] Figure 3B3 is a schematic diagram illustrating another time slot structure 310 in sidelink communication consistent with some embodiments of the present disclosure. The time slot 310 can be used for the first mode or the second mode of resource allocation described above. Figure 3B In the time domain, a time slot 310 includes 14 OFDM symbols, one of which is used for PSFCH, two for DMRS, two for guard period, one for AGC, and the remaining symbols for PSCCH or PSSCH. In the frequency domain, a time slot 310 may include one or more subchannels, each of which is composed of one or more physical resource blocks (PRBs). Similar to the time slot 300, as shown in FIG. Figure 3B As shown, the PSCCH transmission is associated with the lowest subchannel of the scheduled PSSCH. The configuration of the PSCCH (e.g., DMRS, modulation and coding scheme (MCS), number of symbols used) is part of the resource pool configuration. In addition, the indication of which time slots have PSFCH symbols is also part of the resource pool configuration. However, the configuration of the PSSCH (e.g., number of symbols used, DMRS pattern and MCS) is provided by the first-level SCI, which is the payload sent within the PSCCH and follows the configuration described in the 3GPP specifications.

[0030] Figure 4 is a schematic diagram illustrating a method for beam alignment between a UE and a base station consistent with some embodiments of the present disclosure. The UE and the base station may be connected via a Uu interface, as described in the 3GPP specification. Figure 4, a method 400 for beam management between a UE and a base station (e.g., gNB, eNB) includes three phases: phase 1, phase 2, and phase 3. Phase 1 includes step 402, performing Tx beam scanning of the base station by transmitting a synchronization signal block (SSB) from the base station. For example, the base station can generate a synchronization signal (SS) burst to transmit the synchronization signal using Tx beamforming. The SS burst can include multiple consecutive SS blocks (SSB). The SSB can be scanned and transmitted in different angular directions covering the base station. The UE can use a wide Rx beam to receive the SSB. The UE measures the quality of the SSB, for example, the reference signal received power (RSRP) of all SSBs on all UE panels, and selects the best SSB beam. The UE then transmits a physical random access channel (PRACH) on the RACH opportunity associated with the best SSB beam to connect to the base station using a reciprocal Tx beam. The reciprocity between the Rx beam of the UE associated with the best SSB beam transmitted from the base station and the Tx beam of the corresponding UE can be maintained. In particular, at step 404, the UE transmits a random access preamble (message 1 or Msg1) to the base station. Msg1 is a physical layer message. At step 406, the base station transmits a random access response (Random Access Response, RAR) (message 2 or Msg2) to the UE as a response to Msg1. Msg2 is a MAC layer message. At step 408, the UE transmits an RRC connection request or an RRC connection recovery request (message 3 or Msg3) to the base station. Msg3 is an RRC layer request. At step 410, the base station transmits an RRC connection establishment message or an RRC connection recovery message (message 4 or Msg4) to the UE.

[0031] In phase 2, at step 412, the base station may perform Tx beam scanning using the refined downlink Channel State Information-Reference Signal (CSI-RS) beam within the connected SSB beam. The UE may receive the base station's refined downlink CSI-RS beam scanning using a wide Rx beam. The UE measures the quality (e.g., RSRP) of all CSI-RS beams and reports the measurement to the base station. The UE may report the identification (ID) or beam indication of the best beam to the base station.

[0032] In Phase 3, at step 414, the base station transmits repeated CSI-RS beams using the selected beam based on the UE's report in Phase 2. The UE scans the refined Rx beam settings to identify the optimal narrow Rx beam. At the end of Phase 3, alignment between the base station Tx beam and the UE Rx beam is achieved to maximize directional gain. At step 416, the UE may transmit one or more signals or data to the base station.

[0033] Figure 5 1 is a diagram illustrating a method for sidelink beam alignment between two UEs (UE-1 and UE-2) in sidelink communication consistent with some embodiments of the present disclosure. In the sidelink communication, UE-1 may be a primary UE and UE-2 may be a secondary UE. Figure 5 , method 500 includes step 502, performing a discovery process so that UE-1 and UE-2 can become aware of each other. In some embodiments, the discovery process can be performed based on a proximity-based service (ProSe), as described in the 3GPP specification. In some embodiments, the discovery process can be performed based on model A or model B as defined in the 3GPP specification. In one embodiment, UE-1 and UE-2 are two UEs in a V2X system, and discovery occurs at the V2X layer. In this embodiment, discovery can be performed by exchanging Cooperative Awareness Messages (CAM) between the two UEs. The exchange of CAMs between the two UEs can occur in the Intelligent Transport System (ITS) frequency band of 5.9 GHz. In some embodiments, the discovery process can be performed in FR1 or FR2. In this disclosure, FR1 is defined as the frequency range from 410 MHz to 7125 MHz (including sub-6 GHz spectrum), and FR2 is defined as two frequency sub-ranges: FR2-1 from 24250 MHz to 52600 MHz and FR2-2 from 52600 MHz to 71000 MHz (including millimeter wave spectrum).

[0034] Method 500 includes step 504, establishing a device-to-device connection. The device-to-device connection may be a PC5 connection, as described in 3GPP specifications. For example, UE-1 and UE-2 establish a unicast link via a PC5 connection. In some embodiments, the PC5 connection may be performed in FR1 or FR2.

[0035] Method 500 includes step 506 of triggering initial beam alignment. For example, UE-1 or UE-2 may trigger initial beam alignment. In some embodiments, triggering initial beam alignment may be performed in FR1 or FR2. In some embodiments, triggering initial beam alignment may indicate configuration details regarding beam alignment. The configuration for beam alignment may include at least one of the following: a format of a sidelink beam management reference signal (SL-BMRS) to be used in beam alignment, a number of expected beam sweeps, or an expected time period for beam sweeps.

[0036] After the initial beam alignment, method 500 proceeds with the beam alignment process. The beam alignment process includes three stages: stage 1, stage 2, and stage 3. Stage 1 includes step 508, performing wide beam scanning. For example, UE-1 can perform wide beam scanning using sequential wide Tx beams. In some embodiments, wide beam scanning is performed in FR2. In one embodiment, each individual SL-BMRS is transmitted in a single sidelink time slot. In this embodiment, for example, if four wide beam scans are required, UE-1 transmits 4 different sidelink time slots, each time slot applying a different beam. However, the resource format for transmitting SL-BMRS is not limited to this. In some embodiments, individual SL-BMRS are transmitted in any number of time slots or symbols based on pre-configuration at the UE or configuration by the network (e.g., base station). UE-2 can use a wide Rx beam to receive SL-BMRS.

[0037] Phase 1 includes step 510, transmitting a sidelink measurement report. For example, UE-2 performs measurements on the received SL-BMRS and reports the identified best wide SL-BMRS beam to UE-1. For example, UE-2 can identify the best wide SL-BMRS beam based on the received power (highest power) of the SL-BMRS. In some embodiments, UE-2 can report the index or time slot of the best wide SL-BMRS beam to UE-1. In some embodiments, the report can be transmitted in FR1 or FR2. UE-1 can use a wide Rx beam to receive the sidelink measurement report. This corresponds to the completion of Phase 1, and the method proceeds to Phase 2.

[0038] Phase 2 includes step 512, performing narrow beam scanning. For example, UE-1 may perform narrow Tx SL-BMRS beam scanning. In some embodiments, UE-1 may perform narrow SL-BMRS beam scanning in FR2. In some embodiments, each narrow Tx beam scanning utilizes a single time slot. UE-2 may use a wide Rx beam to receive the narrow SL-BMRS beam.

[0039] Phase 2 includes step 514, transmitting a sidelink measurement report. For example, UE-2 may perform measurements on the received narrow SL-BMRS and report the identified best narrow SL-BMRS beam to UE-1. In some embodiments, UE-2 may report the index or time slot of the best narrow SL-BMRS beam to UE-1. In some embodiments, the sidelink measurement may be transmitted in FR1 or FR2. UE-1 may receive the sidelink measurement report using a wide Rx beam. This corresponds to the completion of Phase 2, and method 500 proceeds to Phase 3.

[0040] Phase 3 includes step 516, repeating beam scanning on the selected narrow Tx beam. For example, UE-1 may perform m repetitions (m is an integer) of SL-BMRS scanning using the selected narrow Tx beam. UE-2 may perform narrow Rx beam scanning to identify the optimal narrow Rx beam. At the end of Phase 3, beam alignment between UE-1 and UE-2 is achieved to maximize directional gain, and UE-1 (or UE-2) may transmit signals or data.

[0041] Figure 6 is a diagram illustrating a method for configuration alignment in discontinuous reception (DRX) consistent with some embodiments of the present disclosure. Figure 6 , the method 600 includes step 602, transmitting DRX assistance information. For example, the Rx UE may use Figure 5The method 500 is used to perform sidelink beam alignment with the Tx UE. The Rx UE also transmits DRX assistance information to the Tx UE to inform the Tx UE of the time or time period when the Rx UE wakes up or sleeps. Upon receiving the DRX assistance information, the Tx UE can determine the time when the Tx UE transmits a signal or data to the Rx UE. For example, when the Rx UE wakes up, the Tx UE can transmit a signal or data to the Rx UE. The method 600 includes step 604, forwarding the DRX assistance information to a base station (e.g., a gNB). For example, the Tx UE transmits the DRX assistance information to the base station so that the base station can perceive the DRX time. The method 600 includes step 606, transmitting a DRX configuration. For example, the base station generates a DRX configuration (e.g., a resource configuration for DRX) and transmits the DRX configuration to the Tx UE. The method 600 includes step 608, forwarding the DRX configuration to the Rx UE. For example, the Tx UE transmits the received DRX configuration to the Rx UE. Method 600 includes step 610 of providing a response to the DRX configuration. For example, upon receiving the DRX configuration, the Rx UE may send an acceptance message or a rejection message to the Tx UE. When the Rx UE transmits the acceptance message, the Tx UE may transmit signals or data based on the DRX assistance information and the timing in the DRX configuration, and avoid transmitting signals or data when the Rx UE is dormant. In this manner, power consumption in sidelink communications may be reduced.

[0042] Figure 7A is a schematic diagram illustrating sidelink communication between an Rx UE using a wide beam and two Tx UEs using narrow beams consistent with some embodiments of the present disclosure, Figure 7B FIG is a schematic diagram showing sidelink communication between an Rx UE using a narrow beam and two Tx UEs using narrow beams. Figure 7A , Tx UE-1 and Tx UE-2 use narrow beams to transmit signals or data to Rx UE, and Rx UE uses wide Rx beams to receive signals or data. The wide Rx beam used in Rx UE allows transmissions from both Tx UE-1 and Tx UE-2 to be received at any time, thereby ensuring the stability of sidelink communication. However, continuous use of wide Rx beams may not be practical, especially in high-frequency sidelink communications where beamforming using narrow beams is required to compensate for the high path loss of high-frequency radio signals. Now refer to Figure 7B, Tx UE-1 and Tx UE-2 use narrow beams to transmit signals or data to the Rx UE, and the Rx UE uses the narrow Rx beam to receive the transmission. Although narrow Rx beams can provide advantages for Rx UEs, especially in high-frequency bands, the beam correspondence between narrow Rx beams and narrow Tx beams can be easily lost. In addition, narrow Rx beams may not allow the Rx UE to receive transmissions from multiple UEs (Tx UE-1 and Tx UE-2) simultaneously.

[0043] At least some embodiments of the present disclosure provide for coordinated beam fallback by employing the following 7A to 7B Solution to the problem shown. The coordinated beam fallback mechanism allows two sidelink UEs to maintain communication even if the two sidelink UEs are about to lose beam correspondence. For example, after the Tx UE and the Rx UE have established sidelink beam alignment using a narrow Tx beam and a narrow Rx beam, the Tx UE and the Rx UE establish a coordination process regarding the time when the Rx UE will apply a wide Rx beam, so that the switching of the beam at the Rx UE and / or the Tx UE can be performed before the beam correspondence is completely lost. At least some embodiments of the present disclosure also include a biased resource selection process that allows the Tx UE to preferentially select resources for which the Rx UE applies a wide Rx beam.

[0044] Figure 8 is a diagram illustrating a method for sidelink beam alignment between two UEs (Tx UE and Rx UE) in sidelink communication consistent with some embodiments of the present disclosure. Figure 8 Method 800 includes three phases: an initialization phase, a configuration phase, and an application phase. The initialization phase includes step 802, obtaining a sidelink configuration. The sidelink configuration can be obtained in various ways. In one embodiment, if there is no base station (e.g., a gNB) nearby, or if a base station is nearby but does not transmit a system information block (SIB) 12, the Tx UE (or Rx UE) can use a sidelink configuration preconfigured at the Tx UE (or Rx UE). In one embodiment, if the base station transmits SIB12, the Tx UE (or Rx UE) can obtain the sidelink configuration from the base station. The sidelink configuration may include information about the configuration and access parameters of the sidelink physical channel. The base station is not limited to a gNB; it can be any currently existing base station, such as a base station for LTE or NR, a base station for future generations (e.g., 6G, 7G), or any other future RAT generation.

[0045] The initialization phase includes step 804, where a discovery process is performed between the Tx UE and the Rx UE, enabling the two devices to become aware of each other. In some embodiments, discovery is performed by the application layer of the Tx UE (or Rx UE) generating a notification message or discovery message that is broadcast on a sidelink physical channel. In one embodiment, for example, the application layer of the Rx UE receives a decoded message from the Tx UE and determines whether a unicast connection should be established with the Tx UE. If the application layer of the Rx UE determines that a unicast connection should be established with the Tx UE, the application layer generates a message directed to the Tx UE.

[0046] The initialization phase includes step 806, establishing a device-to-device connection. In one embodiment, the device-to-device connection is a PC5-RRC connection. For example, if the Tx UE and the Rx UE decide to establish a unicast connection, they may establish a PC5-RRC connection. The Tx UE and the Rx UE may also exchange device capabilities. Device capabilities may include beamforming capabilities.

[0047] The initialization phase includes step 808, performing beam alignment between the Tx UE and the Rx UE and establishing beam alignment using the first beam. For example, the Tx UE and the Rx UE may use Figure 5 The method 500 shown in FIG. 5 is used to perform beam alignment. When the three stages of the beam alignment process are completed, as shown in FIG. Figure 5 As shown, the Tx UE and the Rx UE establish beam alignment using a first beam. The first beam can be a narrow beam. The narrow beam can be a directional beam. The UE can adjust the beam width of the narrow beam, for example, by adjusting the number of antenna elements or the beamforming gain. The first beam can be a high-frequency beam, such as FR2.

[0048] After the initialization phase, the method 800 proceeds to the configuration phase. The configuration phase includes step 810, receiving (transmitting) a second beam assist indication. For example, the Rx UE transmits the second beam assist indication to the Tx UE, and the Tx UE receives the transmitted second beam assist indication. In some embodiments, the second beam can be a wide beam (e.g., at least wider than the first beam). The beam width of the wide beam can be adjusted by the Rx UE (or Tx UE), for example, by adjusting the number of antenna elements or beamforming gain, etc. In some embodiments, the second beam is FR1 or FR2. In some embodiments, the Rx UE generates the second beam assist indication based on at least one of the following: one or more channel busy rate (CBR) ranges, the absolute speed range of the Tx UE, the absolute speed range of the Rx UE, the range of relative speeds between the Tx UE and the Rx UE, or priority information of one or more packets transmitted from the Tx UE. The absolute speed range of the Tx UE, the absolute speed range of the Rx UE, and the relative speed range between the Tx UE and the Rx UE can be determined based on the exchange of the absolute speeds and headings of the Tx UE and the Rx UE. In some embodiments, the second beam assistance indication can indicate at least one of time information or frequency information associated with the second beam used by the Rx UE to receive signals or data from the Tx UE. For example, the time information or frequency information may include the time or frequency at which the Rx UE wants to use the second beam as a new Rx beam for receiving signals or data from the Tx UE. In some embodiments, the second beam assistance indication includes assistance information for using the second beam as the second receive beam at the Rx UE, wherein the assistance information includes at least one of the following: a period of the second receive beam, an offset of the second receive beam, a duration of the second receive beam, one or more frequency resources, a receive panel orientation, or a receive beamwidth.

[0049] The configuration phase includes step 812, transmitting (or receiving) a second beam configuration. For example, in response to receiving the second beam assist indication, the Tx UE generates a second beam configuration and transmits the second beam configuration to the Rx UE, and the Rx UE receives the second beam configuration. In some embodiments, the Tx UE generates the second beam configuration based on one or more scheduling constraints of the Tx UE. The one or more scheduling constraints of the Tx UE may include at least one of the following: a receive beam fallback configuration with a third UE that causes receive beam fallback from the second beam; or a pre-existing discontinuous reception configuration that needs to be maintained at the Tx UE. In some embodiments, the second beam configuration includes second receive beam configuration information for a second receive beam to be used by the Rx UE. The second receive beam configuration information may include at least one of the following: a period of the second receive beam, an offset of the second receive beam, a duration of the second receive beam, one or more frequency resources, a receive panel orientation, a receive beam width, acceptance of the configuration included in the second beam assist indication, or rejection of the configuration included in the second beam assist indication.

[0050] The configuration phase includes step 814, receiving (or transmitting) confirmation of the second beam configuration. For example, after transmitting the second beam configuration, the Tx UE may receive confirmation of the second beam configuration from the Rx UE. In some embodiments, the confirmation of the second beam configuration is received via RRC signaling, MAC CE, or physical layer signaling. The physical layer signaling may include at least one of the following: Hybrid Automatic Repeat Request (HARQ), SCI, or PSFCH.

[0051] After the configuration phase, method 800 proceeds to the application phase. The application phase includes step 816 of determining whether resource selection is triggered, where the resource selection is associated with the use of the second beam. For example, upon receiving confirmation of the second beam configuration from the Rx UE, the Tx UE may determine whether resource selection is triggered. In some embodiments, the trigger for selection of the resource includes at least one of: (a) receipt of a Negative Acknowledgement (NACK) message or non-receipt of HARQ feedback in response to transmission of a transport block, (b) receipt of a NACK message or non-receipt of HARQ feedback in response to retransmission of a transport block, (c) a decrease in one or more signal parameters below a first threshold, the one or more signal parameters including at least one of the following: Signal to Interference and Noise Ratio (SINR), RSRP, or Reference Signal Strength Indicator (RSSI), (d) a decrease in one or more signal parameters from a previous state to a current state exceeding a second threshold, the one or more signal parameters including at least one of SINR, RSRP, or RSSI, or (e) non-receipt of a scheduled transmission.

[0052] The application phase includes step 818, where, if resource selection is triggered, the candidate resource set is updated and one or more resources are selected from the updated candidate resource set. For example, in response to determining that resource selection is triggered, the Tx UE may update the candidate resource set and select one or more resources from the updated candidate resource set so that the selected one or more resources are associated with the use of the second beam. The candidate resource set may be any candidate resource set previously set by the Tx UE. In some embodiments, updating the candidate resource set includes excluding one or more resources not associated with the use of the second beam from the candidate resource set to form a new candidate resource set. After the update, the new candidate resource set is associated with the use of the second beam. For example, the new candidate resource set may only include resources associated with the use of the second beam. In some embodiments, the second beam is a wide beam, and resources that do not include wide Rx beam resources are excluded from the previous candidate resource set. In this way, the Tx UE and the Rx UE can switch back and forth between the first beam and the second beam using the above-described fallback mechanism.

[0053] The application phase includes step 820, where one or more signals or messages are transmitted (or received) using one or more resources selected from the updated candidate resource set. For example, the Tx UE may transmit one or more signals or messages to the Rx UE using one or more resources selected from the new candidate resource set. In some embodiments, the one or more signals or messages include at least one of the following: a beam realignment request, a receive beam realignment request, receive beam resources, or reception of a PSFCH.

[0054] By switching the beam back and forth between a first beam (e.g., a narrow beam) and a second beam (e.g., a wide beam), beam gain is achieved compared to a system that uses only a single beam (either the first beam or the second beam). In addition, because the Tx UE and the Rx UE have a fallback mechanism, if communication on the first beam (e.g., a narrow beam) fails, they can achieve faster beam realignment, thereby improving the reliability and efficiency of sidelink communications.

[0055] The methods described in the present disclosure can be applied to any sidelink communication, for example, LTE or NR or future generation (for example, 6G, 7G or any future generation) sidelink communication. The methods described in the present disclosure can also be applied to sidelink communications involving any number of UEs. The methods described in the present disclosure can also be applied to downlink / uplink communications between a base station and a UE. The methods described in the present disclosure can also be applied to other systems, for example, systems that comply with other standards (for example, Institute of Electrical and Electronics Engineers (IEEE) standards, such as IEEE802.11 technology).

[0056] Figure 9 is a block diagram of a UE 900 consistent with some embodiments of the present disclosure. For example, the UE 900 may be Figure 8 TxUE or Rx UE, and execute Figure 8 The UE 900 may be installed in a mobile vehicle or at a fixed location. The UE 900 may take any form, including but not limited to a vehicle, a component installed in a vehicle, a roadside unit, a laptop computer, a wireless terminal including a mobile phone, a wireless handheld device, or a wireless personal device, or any other form.

[0057] Reference Figure 9, UE 900 may include an antenna 902, which may be used for transmission or reception of electromagnetic signals to / from a base station or other UEs. Antenna 902 may include one or more antenna elements and may implement different input-output antenna configurations, such as a Multiple Input Multiple Output (MIMO) configuration, a Multiple Input Single Output (MISO) configuration, and a Single Input Multiple Output (SIMO) configuration. In some embodiments, antenna 902 may include multiple (e.g., dozens or hundreds) of antenna elements and may implement multi-antenna functions such as beamforming. In some embodiments, antenna 902 is a single antenna. In some embodiments, antenna 902 may provide functions such as Figure 5 and Figure 8 The wide beam and narrow beam can be switched between the wide beam and the narrow beam as needed.

[0058] UE 900 may include a transceiver 904 coupled to antenna 902. Transceiver 904 may be a wireless transceiver at UE 900 and may perform bidirectional communication with a base station or other UEs. For example, transceiver 904 may receive wireless signals from a base station / transmit wireless signals to a base station via downlink / uplink communication. Transceiver 904 may also receive / transmit wireless signals from / to another UE or roadside unit via sidelink communication. Transceiver 904 may include a modem to modulate packets and provide the modulated packets to antenna 902 for transmission, as well as to demodulate packets received from antenna 902.

[0059] The UE 900 may include a memory 906. The memory 906 may be any type of computer-readable storage medium, including volatile or non-volatile memory devices or a combination thereof. Computer-readable storage media include, but are not limited to, non-transitory computer storage media. Non-transitory storage media can be accessed by general-purpose or special-purpose computers. Examples of non-transitory storage media include, but are not limited to, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), electrically erasable programmable ROM (EEPROM), digital versatile disks (DVD), flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, etc. Non-transitory media can be used to carry or store desired program code means (e.g., instructions and / or data structures) and can be accessed by general-purpose or special-purpose computers or general-purpose or special-purpose processors. In some examples, the software / program code can be transmitted from a remote source (e.g., a website, server, etc.) using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave. In such examples, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are within the scope of the definition of a medium. Combinations of the above examples are also within the scope of computer-readable media.

[0060] The memory 906 may store information related to the identification of the UE 900 and the signals and / or data received by the antenna 902. The memory 906 may also store post-processed signals and / or data. The memory 906 may also store computer-readable program instructions, mathematical models, and algorithms used in signal processing in the receiver 904 and calculations in the processor 908. The memory 906 may also store computer-readable program instructions executed by the processor 908 to operate the UE 900 to perform various functions described in the present disclosure. In some examples, the memory 906 may include a basic input / output system (BIOS), which may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0061] The computer-readable program instructions of the present disclosure can be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages ​​(including object-oriented programming languages ​​and conventional process programming languages). The computer-readable program instructions can be executed completely on a computing device as an independent software package, or partially on a first computing device and partially on a second computing device away from the first computing device. In the latter case, the second remote computing device can be connected to the first computing device through any type of network, including a local area network (LAN) or a wide area network (WAN).

[0062] The UE 900 may include a processor 908, which may include a hardware device with processing capabilities. The processor 908 may include at least one of a general-purpose processor, a digital signal processor (DSP), a central processing unit (CPU), a microcontroller, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a programmable logic device, discrete gate or transistor logic components, discrete hardware components, or other programmable logic devices. Examples of general-purpose processors include, but are not limited to, a microprocessor, any conventional processor, a controller, a microcontroller, or a state machine. In some embodiments, the processor 908 may be implemented using a combination of devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration). The processor 908 may receive downlink signals or sidelink signals from the transceiver 904 and further process these signals. The processor 908 may also receive data packets from the transceiver 904 and further process these packets. In some embodiments, the processor 908 may be configured to operate a memory using a memory controller. In some embodiments, the memory controller may be integrated into the processor 908. The processor 908 may be configured to execute computer-readable instructions stored in a memory (eg, the memory 906) to cause the UE 900 to perform various functions.

[0063] UE 900 may include a Global Positioning System (GPS) 910. GPS 910 may be used to enable location-based services or other services based on the geographic location of UE 900 and / or synchronization between UEs. GPS 910 may receive Global Navigation Satellite System (GNSS) signals from a single satellite or multiple satellite signals via antenna 902 and provide the geographic location of UE 900 (e.g., coordinates of UE 900). In some embodiments, GPS 910 is omitted. In some embodiments, a timer is included.

[0064] The UE 900 may include an input / output (I / O) device 912, which may be used to transmit the results of signal processing and calculation to a user or another device. The I / O device 912 may include a user interface, which includes a display and an input device to transmit user commands to the processor 908. The display may be configured to display the signal reception status at the UE 900, data stored in the memory 906, signal processing status, and calculation results. The display may include, but is not limited to, a cathode ray tube (CRT), a liquid crystal display (LCD), a light-emitting diode (LED), a gas plasma display, a touch screen, or other image projection device for displaying information to the user. The input device may be any type of computer hardware device for receiving data and control signals from the user. The input device may include, but is not limited to, a keyboard, a mouse, a scanner, a digital camera, a joystick, a trackball, cursor direction keys, a touch screen monitor, or an audio / video commander.

[0065] The UE 900 may also include a machine interface 914 , such as an electrical bus that connects the transceiver 904 , memory 906 , processor 908 , GPS 910 , and I / O devices 912 .

[0066] In some embodiments, UE 900 may be the first UE in sidelink communication (e.g., Figure 8 The processor 908 may be configured or programmed to execute instructions stored in the memory 906 to: establish a connection with a second UE (eg, Figure 8beam alignment of an Rx UE shown); receiving a second beam assistance indication from a second UE, the second beam assistance indication indicating at least one of time information or frequency information associated with a second beam for the second UE for receiving signals or data from the first UE; in response to receiving the second beam assistance indication, transmitting a second beam configuration to the second UE; receiving confirmation of the second beam configuration from the second UE; determining whether selection of a resource is triggered, the selection of the resource being associated with use of the second beam; in response to determining that selection of the resource is triggered, updating a candidate resource set and selecting one or more resources from the updated candidate resource set, so that the selected one or more resources are associated with use of the second beam; and transmitting one or more signals or messages using the one or more resources selected from the updated candidate resource set.

[0067] In some embodiments, UE 900 may be a second UE in sidelink communication (e.g., Figure 8 The processor 908 may be configured or programmed to execute instructions stored in the memory 906 to: establish a connection with the first UE (eg, as shown in FIG. 1 ) using the first beam. Figure 8 The invention also provides a method for transmitting a first beam configuration to the first UE, wherein the second beam configuration is configured to align the beam of the first UE with the Tx UE shown in the figure; transmitting a second beam assistance indication to the first UE, the second beam assistance indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; receiving a second beam configuration from the first UE in response to transmitting the second beam assistance indication; and transmitting a confirmation of the second beam configuration to the first UE.

[0068] As used in this disclosure, the term "or" is used in a list of items to indicate an inclusive list. A list of items can begin with phrases such as "at least one" or "one or more." For example, a list of at least one of A, B, or C includes A or B or C or AB (i.e., A and B) or AC or BC or ABC (i.e., A and B and C). In addition, as used in this disclosure, the phrase "based on" to indicate that a list of conditions should not be interpreted as "based only on" a set of conditions, but rather as "based at least in part on" a set of conditions. For example, a result described as "based on condition A" can be based on both condition A and condition B without departing from the scope of this disclosure.

[0069] In this specification, the terms "include," "comprises," or "contains" are used interchangeably and have the same meaning and should be interpreted as inclusive and open-ended. The terms "include," "comprises," or "contains" can be used before a list of elements and indicate that at least all of the listed elements are present within the list, but additional elements not in the list may also be present. For example, if A includes B and C, then both {B, C} and {B, C, D} are within the scope of A.

[0070] In conjunction with the accompanying drawings, the present disclosure describes example configurations that do not represent all examples that can be implemented or all configurations within the scope of the present disclosure. The term "exemplary" should not be interpreted as "preferred" or "advantageous compared to other examples", but rather as "illustrative, instance, or example". By reading this disclosure, including the description of the embodiments and the accompanying drawings, one of ordinary skill in the art will understand that the technology disclosed herein can be implemented using alternative embodiments. One of ordinary skill in the art will understand that the embodiments described herein or certain features of the embodiments can be combined to arrive at other embodiments for practicing the technology described in this disclosure. Therefore, the present disclosure is not limited to the examples and designs described herein, but is in accordance with the widest scope consistent with the principles and novel features disclosed herein.

[0071] The flowcharts and block diagrams in the accompanying drawings illustrate examples of possible architectures, functions, and operations of systems, methods, and devices according to various embodiments. It should be noted that in some alternative implementations, the functions marked in the blocks may not occur in the order marked in the figures. For example, two blocks shown in succession may actually be executed substantially simultaneously, or the blocks may sometimes be executed in the opposite order, depending on the functions involved. Similarly, in methods consistent with various embodiments, additional steps may be included in such methods, and certain steps may be omitted or combined.

[0072] It should be understood that the described embodiments are not mutually exclusive, and elements, components, materials, or steps described in conjunction with one exemplary embodiment may be combined with or eliminated from other embodiments in a suitable manner to achieve desired design goals.

[0073] Reference herein to "some embodiments" or "some exemplary embodiments" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment. The appearances of the phrases "one embodiment," "some embodiments," or "another embodiment" in various places throughout this disclosure are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

[0074] In addition, the articles "a" and "an" as used in this disclosure and the appended claims should generally be construed to mean "one or more" unless specified otherwise or clear from context to be directed to a singular form.

[0075] Unless expressly stated otherwise, each numerical value and range should be interpreted as approximate as if the word "about" or "approximately" preceded the value or range.

[0076] Although elements in the following method claims, if any, are recited in a specific order, those elements are not necessarily intended to be limited to implementation in that specific order unless the claim recitation otherwise implies a specific order for implementation of some or all of those elements.

[0077] It should be understood that certain features of the present disclosure that are described in the context of separate embodiments for the sake of clarity may also be provided in combination in a single embodiment. Conversely, various features of this specification that are described in the context of a single embodiment for the sake of brevity may also be provided individually or in any suitable subcombination or in any other described embodiment of this specification as appropriate. Certain features described in the context of various embodiments are not essential features of those embodiments unless so indicated.

[0078] It should also be understood that various modifications, substitutions and changes may be made by those skilled in the art to the details, materials and arrangements of the components described and shown for the purpose of explaining the nature of the described embodiments without departing from the scope. Therefore, the appended claims encompass all such substitutions, modifications and changes that fall within the terms of the claims.

[0079] 1. Clause 1: A first user equipment (UE) for sidelink communication, the first UE comprising: a memory storing instructions; and a processor configured to execute the instructions stored in the memory to: establishing beam alignment with a second UE using the first beam; receiving a second beam assisting indication from the second UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to receiving the second beam assist indication, transmitting a second beam configuration to the second UE; receiving, from the second UE, a confirmation of the second beam configuration; determining whether selection of a resource is triggered, the selection of the resource being associated with use of the second beam; In response to determining that selection of the resource is triggered, updating a set of candidate resources and selecting one or more resources from the updated set of candidate resources such that the selected one or more resources are associated with use of the second beam; as well as One or more signals or messages are transmitted using the one or more resources selected from the updated set of candidate resources.

[0080] Clause 2: The first UE of clause 1, wherein, when updating the candidate resource set, the processor is further configured to execute the instructions to: One or more resources not associated with use of the second beam are excluded from the candidate resource set to form a new candidate resource set.

[0081] Clause 3: The first UE of clause 2, wherein the new candidate resource set is associated with usage of the second beam.

[0082] Clause 4: The first UE of clause 1, wherein the second beam is wider than the first beam.

[0083] Clause 5: A first UE according to clause 1, wherein the second beam assistance indication includes assistance information for using the second beam as a second receive beam, the assistance information including at least one of: a period of the second receive beam, an offset of the second receive beam, a duration of the second receive beam, one or more frequency resources, a receive panel orientation, or a receive beam width.

[0084] Clause 6: The first UE of clause 1, wherein the processor is further configured to execute the instructions to: The second beam configuration is generated based on one or more scheduling constraints of the first UE.

[0085] Clause 7: The first UE of clause 6, wherein the one or more scheduling constraints of the first UE include at least one of the following: causing a receive beam fallback configuration with a third UE that causes receive beam fallback from the second beam, or Pre-existing DRX configurations need to be maintained.

[0086] Clause 8: A first UE according to clause 1, wherein the second beam configuration includes second receive beam configuration information, and the second receive beam configuration information includes at least one of the following: a period of the second receive beam, an offset of the second receive beam, a duration of the second receive beam, one or more frequency resources, a receive panel orientation, a receive beam width, acceptance of the configuration included in the second beam assistance indication, or rejection of the configuration included in the second beam assistance indication.

[0087] Clause 9: The first UE according to clause 1, wherein the confirmation of the second beam configuration is transmitted via radio resource control (RRC) signaling, medium access control (MAC) control element (CE) signaling, or physical layer signaling.

[0088] Clause 10: The first UE of clause 9, wherein the physical layer signaling comprises at least one of: hybrid automatic repeat request (HARQ), sidelink control information (SCI), or a physical sidelink feedback channel (PSFCH).

[0089] Clause 11: The first UE of clause 1, wherein the triggering of the selection of the resource comprises at least one of: (a) receipt of a negative acknowledgement (NACK) message or non-receipt of HARQ feedback in response to the transmission of a transport block, (b) in response to a retransmission of the transport block, receipt of a NACK message or non-receipt of HARQ feedback, (c) one or more signal parameters decrease below a first threshold, the one or more signal parameters comprising at least one of: a signal to interference and noise ratio (SINR), a reference signal received power (RSRP), or a reference signal strength indicator (RSSI), (d) a decrease in one or more signal parameters from a previous state to a current state exceeds a second threshold, the one or more signal parameters including at least one of SINR, RSRP, or RSSI, or (e) Non-receipt of scheduled transmission.

[0090] Clause 12: The first UE of clause 1, wherein the one or more signals or messages include at least one of: a beam realignment request, a receive beam realignment request, receive beam resources, or reception of a PSFCH.

[0091] Clause 13: The first UE of clause 1, wherein, when establishing beam alignment with the second UE using the first beam, the processor is further configured to execute the instructions to: Obtain a sidelink configuration or obtain a sidelink pre-configuration from the network; discover the second UE using a discovery message; establish a unicast connection with the second UE; and perform a beam alignment process to establish the beam alignment with the second UE using the first beam.

[0092] Clause 14: The first UE of clause 1, wherein the first UE is a transmitting UE in the sidelink communication and the second UE is a receiving UE in the sidelink communication.

[0093] Clause 15: The first UE of clause 1, wherein the first beam is FR2 and the second beam is FR1 or FR2.

[0094] Clause 16: A second user equipment (UE) for sidelink communication, the second UE comprising: a memory storing instructions; and a processor configured to execute the instructions stored in the memory to: establishing beam alignment with the first UE using the first beam; transmitting a second beam assisting indication to the first UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to transmitting the second beam assist indication, receiving a second beam configuration from the first UE; and Transmit a confirmation of the second beam configuration to the first UE.

[0095] Clause 17: The second UE of clause 16, wherein the second beam is wider than the first beam.

[0096] Clause 18: A second UE according to clause 16, wherein the second beam assist indication is generated based on at least one of: one or more channel busy rate (CBR) ranges, an absolute speed range of the first UE, an absolute speed range of the second UE, a range of relative speeds between the first UE and the second UE, or priority information of one or more packets transmitted from the first UE.

[0097] Clause 19: The second UE of clause 18, wherein the absolute speed range of the first UE, the absolute speed range of the second UE, and the range of relative speeds between the first UE and the second UE are determined based on an exchange of the absolute speeds and headings of the first UE and the second UE.

[0098] Clause 20: A method for beam management in sidelink communications, the method comprising: Establishing, by a first UE in the sidelink communication, beam alignment with a second UE using a first beam; receiving a second beam assisting indication from the second UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to receiving the second beam assist indication, transmitting a second beam configuration to the second UE; receiving, from the second UE, a confirmation of the second beam configuration; determining, by the first UE, whether selection of a resource is triggered, the selection of the resource being associated with use of the second beam; In response to determining that selection of the resource is triggered, updating a set of candidate resources and selecting one or more resources from the updated set of candidate resources such that the selected one or more resources are associated with use of the second beam; and One or more signals or messages are transmitted using the one or more resources selected from the updated set of candidate resources.

[0099] Clause 21: The method of clause 20, wherein updating the candidate resource set further comprises: One or more resources not associated with use of the second beam are excluded from the candidate resource set to form a new candidate resource set.

[0100] Clause 22: The method of clause 21, wherein the new set of candidate resources is associated with use of a second beam.

[0101] Clause 23: The method of clause 20, wherein the second beam is wider than the first beam.

[0102] Clause 24: A method according to clause 20, wherein the second beam auxiliary indication includes auxiliary information for using the second beam as a second receive beam, the auxiliary information including at least one of the following: a period of the second receive beam, an offset of the second receive beam, a duration of the second receive beam, one or more frequency resources, a receive panel orientation, or a receive beam width.

[0103] Clause 25: The method according to clause 20, further comprising: The second beam configuration is generated based on one or more scheduling constraints of the first UE.

[0104] Clause 26: The method of clause 25, wherein the one or more scheduling constraints of the first UE include at least one of: causing a receive beam fallback configuration with a third UE that causes receive beam fallback from the second beam, or Pre-existing DRX configurations need to be maintained.

[0105] Clause 27: A method according to clause 20, wherein the second beam configuration includes second receive beam configuration information, and the second receive beam configuration information includes at least one of the following: a period of the second receive beam, an offset of the second receive beam, a duration of the second receive beam, one or more frequency resources, a receive panel orientation, a receive beam width, acceptance of the configuration included in the second beam auxiliary indication, or rejection of the configuration included in the second beam auxiliary indication.

[0106] Clause 28: A method according to clause 20, wherein the confirmation of the second beam configuration is transmitted over radio resource control (RRC) signaling, medium access control (MAC) control element (CE) signaling or physical layer signaling.

[0107] Clause 29: The method of clause 28, wherein the physical layer signaling comprises at least one of: hybrid automatic repeat request (HARQ), sidelink control information (SCI), or a physical sidelink feedback channel (PSFCH).

[0108] Clause 30: The method of clause 20, wherein the triggering of the selection of the resource comprises at least one of: (a) receipt of a negative acknowledgement (NACK) message or non-receipt of HARQ feedback in response to the transmission of a transport block, (b) in response to a retransmission of the transport block, receipt of a NACK message or non-receipt of HARQ feedback, (c) one or more signal parameters decrease below a first threshold, the one or more signal parameters comprising at least one of: a signal to interference and noise ratio (SINR), a reference signal received power (RSRP), or a reference signal strength indicator (RSSI), (d) a decrease in one or more signal parameters from a previous state to a current state exceeds a second threshold, the one or more signal parameters including at least one of SINR, RSRP, or RSSI, or (e) Non-receipt of scheduled transmission.

[0109] Clause 31: The method of clause 20, wherein the one or more signals or messages comprise at least one of: a beam realignment request, a receive beam realignment request, receive beam resources, or reception of a PSFCH.

[0110] Clause 32: The method of clause 20, wherein establishing beam alignment with the second UE using the first beam further comprises: Obtaining sidelink configuration from the network or obtaining sidelink pre-configuration; discovering the second UE using a discovery message; establishing a unicast connection with the second UE; and A beam alignment procedure is performed to establish the beam alignment with the second UE using the first beam.

[0111] Clause 33: The method of clause 20, wherein the first UE is a transmitting UE in the sidelink communication and the second UE is a receiving UE in the sidelink communication.

[0112] Clause 34: The method of clause 20, wherein the first beam is FR2 and the second beam is FR1 or FR2.

[0113] Clause 35: A method for beam management in sidelink communications, the method comprising: establishing, by a second user equipment (UE) in the sidelink communication, beam alignment with the first UE using the first beam; transmitting a second beam assisting indication to the first UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to transmitting the second beam assist indication, receiving a second beam configuration from the first UE; and Transmit a confirmation of the second beam configuration to the first UE.

[0114] Clause 36: A method according to clause 35, wherein the second beam assist indication is generated based on at least one of: one or more channel busy rate (CBR) ranges, an absolute speed range of the first UE, an absolute speed range of the second UE, a range of relative speeds between the first UE and the second UE, or priority information of one or more packets transmitted from the first UE.

[0115] Clause 37: A method according to clause 36, wherein the absolute speed range of the first UE, the absolute speed range of the second UE, and the range of relative speeds between the first UE and the second UE are determined based on the exchange of absolute speeds and headings of the first UE and the second UE using the first beam.

[0116] Clause 38: A non-transitory computer-readable medium storing instructions executable by one or more processors of a first user equipment (UE) for sidelink communication to perform a method comprising: Establishing, by the first UE, beam alignment with a second UE using a first beam for the sidelink communication; receiving a second beam assisting indication from the second UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to receiving the second beam assist indication, transmitting a second beam configuration to the second UE; receiving, from the second UE, a confirmation of the second beam configuration; determining, by the first UE, whether selection of a resource is triggered, the selection of the resource being associated with use of the second beam; In response to determining that selection of the resource is triggered, updating a set of candidate resources and selecting one or more resources from the updated set of candidate resources such that the selected one or more resources are associated with use of the second beam; and One or more signals or messages are transmitted using the one or more resources selected from the updated set of candidate resources.

[0117] Clause 39: A non-transitory computer-readable medium storing instructions executable by one or more processors of a second user equipment (UE) for sidelink communication to perform a method comprising: establishing beam alignment with a first UE using a first beam for the sidelink communication; transmitting a second beam assisting indication to the first UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to transmitting the second beam assist indication, receiving a second beam configuration from the first UE; and Transmit a confirmation of the second beam configuration to the first UE.

Claims

1. A first user equipment (UE) for sidelink communication, the first UE comprising: a memory that stores instructions; as well as a processor configured to execute the instructions stored in the memory to: establishing beam alignment with a second UE using the first beam; receiving a second beam assisting indication from the second UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to receiving the second beam assist indication, transmitting a second beam configuration to the second UE; receiving, from the second UE, a confirmation of the second beam configuration; determining whether selection of a resource is triggered, the selection of the resource being associated with use of the second beam; In response to determining that selection of the resource is triggered, updating a set of candidate resources and selecting one or more resources from the updated set of candidate resources such that the selected one or more resources are associated with use of the second beam; as well as One or more signals or messages are transmitted using the one or more resources selected from the updated set of candidate resources.

2. The first UE according to claim 1, wherein: When updating the candidate resource set, the processor is further configured to execute the instructions to: One or more resources not associated with use of the second beam are excluded from the candidate resource set to form a new candidate resource set.

3. The first UE according to claim 1, wherein: The second beam is wider than the first beam.

4. The first UE according to claim 1, wherein: The second beam assistance indication includes assistance information for using the second beam as a second receive beam, the assistance information including at least one of the following: a period of the second receive beam, an offset of the second receive beam, a duration of the second receive beam, one or more frequency resources, a receive panel orientation, or a receive beam width. The first UE according to claim 1 , wherein: The processor is further configured to execute the instructions to: The second beam configuration is generated based on one or more scheduling constraints of the first UE. The first UE according to claim 1 , wherein: The one or more scheduling constraints of the first UE include at least one of the following: causing a receive beam fallback configuration with a third UE that causes receive beam fallback from the second beam, or Pre-existing DRX configurations need to be maintained.

7. The first UE according to claim 1, wherein: The second beam configuration includes second receive beam configuration information, and the second receive beam configuration information includes at least one of the following: a period of the second receive beam, an offset of the second receive beam, a duration of the second receive beam, one or more frequency resources, a receive panel orientation, a receive beam width, acceptance of the configuration included in the second beam assistance indication, or rejection of the configuration included in the second beam assistance indication.

8. The first UE according to claim 1, wherein: The confirmation of the second beam configuration is transmitted through radio resource control (RRC) signaling, medium access control (MAC) control element (CE) signaling or physical layer signaling.

9. The first UE according to claim 1, wherein: The triggering of the resource selection includes at least one of the following: (a) receipt of a negative acknowledgement (NACK) message or non-receipt of HARQ feedback in response to the transmission of a transport block, (b) in response to a retransmission of the transport block, receipt of a NACK message or non-receipt of HARQ feedback, (c) one or more signal parameters decrease below a first threshold, the one or more signal parameters comprising at least one of: a signal to interference and noise ratio (SINR), a reference signal received power (RSRP), or a reference signal strength indicator (RSSI), (d) a decrease in one or more signal parameters from a previous state to a current state exceeds a second threshold, the one or more signal parameters including at least one of SINR, RSRP, or RSSI, or Non-receipt of a scheduled transmission.

10. The first UE according to claim 1, wherein: The one or more signals or messages include at least one of: a beam realignment request, a receive beam realignment request, receive beam resources, or reception of a PSFCH.

11. The first UE according to claim 1, wherein: When establishing beam alignment with the second UE using the first beam, the processor is further configured to execute the instructions to: Obtaining sidelink configuration from the network or obtaining sidelink pre-configuration; discovering the second UE using a discovery message; establishing a unicast connection with the second UE; as well as A beam alignment procedure is performed to establish the beam alignment with the second UE using the first beam.

12. A second user equipment (UE) for sidelink communication, the second UE comprising: a memory that stores instructions; as well as a processor configured to execute the instructions stored in the memory to: establishing beam alignment with the first UE using the first beam; transmitting a second beam assisting indication to the first UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to transmitting the second beam assist indication, receiving a second beam configuration from the first UE; and Transmit a confirmation of the second beam configuration to the first UE.

13. The second UE according to claim 12, wherein: The second beam is wider than the first beam.

14. The second UE according to claim 12, wherein: The second beam assist indication is generated based on at least one of: one or more channel busy rate (CBR) ranges, an absolute speed range of the first UE, an absolute speed range of the second UE, a range of relative speeds between the first UE and the second UE, or priority information of one or more packets transmitted from the first UE.

15. The second UE according to claim 14, wherein: The absolute speed range of the first UE, the absolute speed range of the second UE, and the range of relative speeds between the first UE and the second UE are determined based on an exchange of the absolute speeds and headings of the first UE and the second UE.

16. A method for beam management in sidelink communications, the method comprising: Establishing, by a first UE in the sidelink communication, beam alignment with a second UE using a first beam; receiving a second beam assisting indication from the second UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to receiving the second beam assist indication, transmitting a second beam configuration to the second UE; receiving, from the second UE, a confirmation of the second beam configuration; determining, by the first UE, whether selection of a resource is triggered, the selection of the resource being associated with use of the second beam; In response to determining that selection of the resource is triggered, updating a set of candidate resources and selecting one or more resources from the updated set of candidate resources such that the selected one or more resources are associated with use of the second beam; as well as One or more signals or messages are transmitted using the one or more resources selected from the updated set of candidate resources.

17. The method according to claim 16, wherein: Updating the candidate resource set further includes: One or more resources not associated with use of the second beam are excluded from the candidate resource set to form a new candidate resource set.

18. A method for beam management in sidelink communications, the method comprising: establishing, by a second user equipment (UE) in the sidelink communication, beam alignment with the first UE using the first beam; transmitting a second beam assisting indication to the first UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to transmitting the second beam assist indication, receiving a second beam configuration from the first UE; and Transmit a confirmation of the second beam configuration to the first UE.

19. A non-transitory computer-readable medium storing instructions executable by one or more processors of a first user equipment (UE) for sidelink communication to perform a method comprising: establishing, by the first UE, beam alignment with a second UE for the sidelink communication using a first beam; receiving a second beam assisting indication from the second UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to receiving the second beam assist indication, transmitting a second beam configuration to the second UE; receiving, from the second UE, a confirmation of the second beam configuration; determining, by the first UE, whether selection of a resource is triggered, the selection of the resource being associated with use of the second beam; In response to determining that selection of the resource is triggered, updating a set of candidate resources and selecting one or more resources from the updated set of candidate resources such that the selected one or more resources are associated with use of the second beam; as well as One or more signals or messages are transmitted using the one or more resources selected from the updated set of candidate resources.

20. A non-transitory computer-readable medium storing instructions executable by one or more processors of a second user equipment (UE) for sidelink communication to perform a method comprising: establishing beam alignment with a first UE for the sidelink communication using a first beam; transmitting a second beam assisting indication to the first UE, the second beam assisting indication indicating at least one of time information or frequency information associated with a second beam for the second UE to receive a signal or data from the first UE; In response to transmitting the second beam assist indication, receiving a second beam configuration from the first UE; and Transmit a confirmation of the second beam configuration to the first UE.

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