Beam reporting

Abstract

Embodiments of the present disclosure relate to beam reporting. In one aspect, a first terminal device determines availability of at least one of a plurality of beams associated with at least one reference signal transmitted by a second terminal device based on a measured signal level and / or quality; performing a beam-by-beam comparison between at least one of the plurality of beams determined to be available, where the beam-by-beam comparison is based on the measured signal level and / or quality for identifying at least one beam having the most suitable signal level and / or quality for signal transmission; and transmitting, to a second terminal device, an indication indicating at least one of the following: at least one beam having the most suitable signal level and / or quality; or at least one beam of the plurality of beams is available. Embodiments of the present disclosure may cause fast beam reporting.

Description

Technical Field

[0001] Various example embodiments relate to the field of telecommunications, and in particular to methods, terminal devices, apparatuses, and computer-readable storage media for beam reporting. Background Art

[0002] In the field of communications, there is a continuous development to provide efficient and reliable solutions for utilizing wireless communication networks. Each new generation presents technical challenges in terms of handling different situations and processes required to connect and serve devices connected to wireless networks. In order to meet the growing demand for wireless data services since the deployment of the fourth generation (4G) communication system, efforts are being made to develop improved fifth generation (5G) or pre-5G (pre-5G) communication systems. The new communication system can support various types of service applications for terminal devices.

[0003] In recent communication technologies, for example, in RAN#94-e, the WID for NR (New Radio) sidelink evolution was agreed and recently revised in RAN#99 (RP-230077). The WID includes the following objectives for sidelink operation in FR2: Study enhanced sidelink operation on FR2 licensed spectrum [RAN1, RAN2] (determine in RAN#98-e whether to continue research or research + specification work in FR2 until the end of R18). Only focus on the update of evaluation methods for commercial deployment scenarios in Q4 2022. [RAN1]. The study is limited to supporting sidelink beam management (including initial beam pairing, beam maintenance and beam failure recovery, etc.) by reusing the existing sidelink CSI framework and reusing the Uu beam management concept as much as possible. [RAN1, RAN2]. Beam management in FR2 licensed spectrum only considers sidelink unicast communication. Summary of the invention

[0004] In general, example embodiments of the present disclosure provide a solution for beam reporting.

[0005] In a first aspect, a first terminal device is provided. The first terminal device comprises at least one processor; and at least one memory comprising computer program code; the at least one memory and the computer program code are configured to, together with the at least one processor, cause the device to: determine the availability of at least one beam of a plurality of beams associated with at least one reference signal transmitted by a second terminal device based on measured signal levels and / or qualities; perform a beam-by-beam comparison between at least one beam of the plurality of beams determined to be available, wherein the beam-by-beam comparison is based on the measured signal levels and / or qualities for identifying at least one beam with the most suitable signal level and / or quality for signal transmission; and send an indication to the second terminal device indicating at least one of the following: at least one beam with the most suitable signal level and / or quality; or at least one beam of the plurality of beams is available.

[0006] In a second aspect, a second terminal device is provided. The second terminal device includes at least one processor; and at least one memory including computer program code; the at least one memory and the computer program code are configured to, together with the at least one processor, cause the device to: send at least one reference signal associated with at least one of the plurality of beams to the first terminal device; monitor from the first terminal device an indication indicating at least one of the following: at least one beam having the most suitable signal level and / or quality among the plurality of beams; or at least one beam among the plurality of beams is available; and determine one or more beams of at least one of the plurality of beams for signal transmission based on the monitoring.

[0007] In a third aspect, a method implemented at a first terminal device is provided. The method comprises: determining, at the first terminal device, availability of at least one beam of a plurality of beams associated with at least one reference signal transmitted by a second terminal device based on a measured signal level and / or quality; performing a beam-by-beam comparison between at least one beam of the plurality of beams determined to be available, wherein the beam-by-beam comparison is based on the measured signal level and / or quality for identifying at least one beam having a most suitable signal level and / or quality for signal transmission; and sending an indication to the second terminal device indicating at least one of the following: at least one beam having a most suitable signal level and / or quality; or at least one beam of the plurality of beams is available.

[0008] In a fourth aspect, a method implemented at a second terminal device is provided. The method comprises: at the second terminal device, sending at least one reference signal associated with at least one of a plurality of beams to a first terminal device; monitoring from the first terminal device an indication indicating at least one of the following: at least one beam having a most suitable signal level and / or quality among the plurality of beams; or at least one of the plurality of beams is available; and determining one or more beams of at least one of the plurality of beams for signal transmission based on the monitoring.

[0009] In a fifth aspect, an apparatus is provided, comprising: a component for determining, at a first terminal device, the availability of at least one beam among a plurality of beams associated with at least one reference signal sent by a second terminal device based on a measured signal level and / or quality; a component for performing a beam-by-beam comparison between at least one beam among the plurality of beams determined to be available, wherein the beam-by-beam comparison is based on the measured signal level and / or quality for identifying at least one beam having the most suitable signal level and / or quality for signal transmission; and a component for sending an indication to the second terminal device indicating at least one of the following: at least one beam having the most suitable signal level and / or quality; or at least one beam among the plurality of beams is available.

[0010] In a sixth aspect, an apparatus is provided, comprising: a component for sending at least one reference signal associated with at least one of a plurality of beams to a first terminal device at a second terminal device; a component for monitoring from the first terminal device an indication of at least one of the following: at least one beam having a most suitable signal level and / or quality among the plurality of beams; or at least one beam among the plurality of beams is available; and a component for determining, based on the monitoring, one or more beams of at least one of the plurality of beams for signal transmission.

[0011] In a seventh aspect, a non-transitory computer-readable medium is provided, the medium comprising program instructions for causing an apparatus to at least execute a method according to any one of the third to fourth aspects above.

[0012] In an eighth aspect, there is provided a computer program comprising instructions which, when executed by an apparatus, causes the apparatus to at least: determine the availability of at least one beam among a plurality of beams associated with at least one reference signal sent by a second terminal device based on a measured signal level and / or quality; perform a beam-by-beam comparison between at least one beam among the plurality of beams determined to be available, wherein the beam-by-beam comparison is based on the measured signal level and / or quality for identifying at least one beam having the most suitable signal level and / or quality for signal transmission; and send an indication to the second terminal device indicating at least one of the following: at least one beam having the most suitable signal level and / or quality; or at least one beam among the plurality of beams is available.

[0013] In a ninth aspect, there is provided a computer program comprising instructions which, when executed by an apparatus, cause the apparatus to at least: send at least one reference signal associated with at least one of a plurality of beams to a first terminal device; monitor from the first terminal device an indication of at least one of: at least one beam having a most suitable signal level and / or quality among the plurality of beams; or at least one of the plurality of beams is available; and determine, based on the monitoring, one or more beams of at least one of the plurality of beams for signal transmission.

[0014] In a tenth aspect, a first terminal device is provided. The first terminal device comprises: a determining circuit system configured to determine the availability of at least one beam of a plurality of beams associated with at least one reference signal transmitted by a second terminal device based on a measured signal level and / or quality; an executing circuit system configured to perform a beam-by-beam comparison between at least one beam of the plurality of beams determined to be available, wherein the beam-by-beam comparison is based on the measured signal level and / or quality for identifying at least one beam with the most suitable signal level and / or quality for signal transmission; and a transmitting circuit system configured to transmit an indication to the second terminal device indicating at least one of the following: at least one beam with the most suitable signal level and / or quality; or at least one beam of the plurality of beams is available.

[0015] In an eleventh aspect, a second terminal device is provided. The second terminal device includes: a transmission circuit system configured to send at least one reference signal associated with at least one of the plurality of beams to the first terminal device; a monitoring circuit system configured to monitor from the first terminal device an indication indicating at least one of the following: at least one beam having the most suitable signal level and / or quality among the plurality of beams; or at least one beam among the plurality of beams is available; and a determination circuit system configured to determine one or more beams among at least one of the plurality of beams for signal transmission based on the monitoring.

[0016] It should be understood that the invention summary is not intended to determine the key or essential features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Some example embodiments will now be described with reference to the accompanying drawings, in which:

[0018] Figure 1A An example system is shown in which embodiments of the present disclosure may be implemented;

[0019] Figure 1B An example of a sidelink timeslot configuration including PSFCH resources for HARQ feedback is shown;

[0020] Figure 1C An example of a Uu beam alignment process is shown;

[0021] Figure 1D An example of a possible sidelink initial beam alignment process is shown;

[0022] Figure 1E Some examples of transmit beams at UE A and receive beams at UE B for sidelink communication are shown;

[0023] Figure 1F A schematic diagram showing transmit beam training and corresponding beam reporting using PSFCH according to some schemes is shown;

[0024] Figure 2 A flow chart illustrating a beam reporting process according to some embodiments of the present disclosure is shown;

[0025] Figure 3 A schematic diagram showing transmit beam training and enhanced beam reporting using PSFCH according to some embodiments of the present disclosure is shown;

[0026] Figure 4 A schematic diagram showing transmit beam training and enhanced beam reporting using PSFCH according to some other embodiments of the present disclosure is shown;

[0027] Figure 5 A flowchart illustrating the operation of beam reporting at an Rx UE according to some embodiments of the present disclosure;

[0028] Figure 6 A flowchart of a method implemented at a first terminal device according to some embodiments of the present disclosure is shown;

[0029] Figure 7 A flowchart of a method implemented at a second terminal device according to some embodiments of the present disclosure is shown;

[0030] Figure 8 shows a simplified block diagram of an apparatus suitable for implementing an embodiment of the present disclosure; and

[0031] Fig. 9 A block diagram of an example computer-readable medium is shown in accordance with some embodiments of the present disclosure.

[0032] Throughout the drawings, the same or similar reference numerals refer to the same or similar elements. DETAILED DESCRIPTION

[0033] The principle of the present disclosure will now be described with reference to some example embodiments. It should be understood that these embodiments are described only to illustrate and help those skilled in the art to understand and implement the present disclosure, and do not represent any limitation on the scope of the present disclosure. The disclosure described herein can be implemented in various other ways except the way described below.

[0034] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0035] In this disclosure, references to "one embodiment," "an embodiment," and "an example embodiment" indicate that the described embodiment may include a particular feature, structure, or characteristic, but not every embodiment must include the particular feature, structure, or characteristic. In addition, such phrases do not necessarily refer to the same embodiment. In addition, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, those skilled in the art believe that it is within the knowledge of those skilled in the art to affect such feature, structure, or characteristic in conjunction with other embodiments, whether or not explicitly described.

[0036] It should be understood that although the terms "first" and "second" etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the exemplary embodiments, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. As used herein, the term "and / or" includes any and all combinations of one or more of the listed terms.

[0037] The terms used herein are only used to describe specific embodiments, and are not intended to limit exemplary embodiments. The singular forms "a", "an" and "the" used herein also include plural forms, unless the context clearly states otherwise. It is further understood that the terms "comprises", "comprising", "has", "having", "includes" and / or "including" specify the presence of the features, elements and / or components when used in this article, but do not exclude the presence or addition of one or more other features, elements, components and / or their combinations. As used herein, "at least one of the following: <list of two or more elements>" and "at least one of the list of <two or more elements>" and similar wording (wherein the list of two or more elements is connected by "and" or "or") refer to at least any one of these elements, or at least any two or more of these elements, or at least all of these elements.

[0038] As used in this application, the term "circuitry" may refer to one, more, or all of the following:

[0039] (a) a pure hardware circuit implementation (such as an implementation using only analog and / or digital circuitry), and

[0040] (b) a combination of hardware circuitry and software such as (where applicable):

[0041] (i) a combination of analog and / or digital hardware circuits and software / firmware, and

[0042] (ii) any portion of hardware processor(s) (including digital signal processor(s)), software and memory(s) with software that work together to enable a device (such as a mobile phone or server) to perform various functions, and

[0043] (c) Hardware circuit(s) and / or processor(s), such as microprocessor(s) or portion(s) of microprocessor(s), which requires software (e.g., firmware)

[0044] The software can be operated, but it can be not saved when the operation is not needed.

[0045] This definition of circuitry applies to all uses of the term in this application, including in any claims. As another example, as used in this application, the term circuitry also covers an implementation of only a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its accompanying software and / or firmware. For example, if applicable to a particular claim element, the term circuitry also covers a baseband integrated circuit or processor integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular network device, or other computing or network device.

[0046] As used herein, the term "communication network" refers to a network that complies with any suitable communication standard, such as Long Term Evolution (LTE), Advanced LTE (LTE-A), Wideband Code Division Multiple Access (WCDMA), High Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IoT), etc. In addition, the communication between the terminal device and the network device in the communication network can be performed according to any suitable generation of communication protocol, including but not limited to the first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, future fifth generation (5G) communication protocol, and / or any other protocol currently known or to be developed in the future. The embodiments of the present disclosure can be applied to various communication systems. In view of the rapid development of communication, there will certainly be future types of communication technologies and systems that can embody the present disclosure. The scope of the present disclosure should not be limited to the above-mentioned systems.

[0047] As used herein, the term "network device" refers to a node in a communication network via which a terminal device can access the network and receive services therefrom. A network device may refer to a base station (BS) or an access point (AP), for example, a NodeB (NodeB or NB), an evolved NodeB (eNodeB or eNB), a NR NB (also known as a gNB), a remote radio unit (RRU), a radio head (RH), a remote radio head (RRH), a relay, a low power node (such as a femto, a pico), etc., depending on the terminology and technology applied.

[0048] The term "terminal device" refers to any terminal device capable of wireless communication. As an example and not limitation, a terminal device may also be referred to as a communication device, a user equipment (UE), a subscriber station (SS), a portable subscriber station, a mobile station (MS), or an access terminal (AT). The terminal device may include, but is not limited to, a mobile phone, a cellular phone, a smart phone, a voice over IP (VoIP) phone, a wireless local loop phone, a tablet computer, a wearable terminal device, a personal digital assistant (PDA), a portable computer, a desktop computer, an image capture terminal device such as a digital camera, a game terminal device, a music storage and playback device, a vehicle-mounted wireless terminal device, a wireless endpoint, a mobile station, a laptop embedded device (LEE), a laptop mounted device (LME), a USB dongle, a smart device, a wireless customer premises equipment (CPE), an Internet of Things (IoT) device, a watch or other wearable device, a head mounted display (HMD), a vehicle, a drone, medical equipment and applications (e.g., remote surgery), industrial equipment and applications (e.g., robots and / or other wireless devices operating in the context of an industrial and / or automated processing chain), consumer electronic devices, devices operating on commercial and / or industrial wireless networks, etc. In the following description, the terms “terminal device”, “communication device”, “terminal”, “user equipment” and “UE” may be used interchangeably.

[0049] In some embodiments of the present disclosure, a scheme related to fast beam reporting for beam training in FR2 sidelink communication is proposed. The principles and embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0050] First reference Figure 1A , Figure 1A An example system 100 is shown in which an embodiment of the present disclosure may be implemented. The system 100 includes a plurality of terminal devices, such as a first terminal device 110 and a second terminal device 120. The first terminal device 110 and the second terminal device 120 may perform sidelink communications with each other, and there may be a transmit beam training process for the sidelink communications. In some examples, the second terminal device 120 may be a terminal device for transmitting a reference signal, such as a Tx (transmit) UE. The first terminal device 110 may be a terminal device for receiving a reference signal, such as an Rx (receive) UE. In some examples, the first terminal device 110 may send feedback for a reference signal to the second terminal device 120, for example, via a physical sidelink feedback channel (PSFCH) resource.

[0051] It should be understood that the number of terminal devices is for illustration purposes only and is not intended to be limiting. System 100 may include any suitable number of terminal devices suitable for implementing the embodiments of the present disclosure. Although not shown, it should be understood that system 100 may also include one or more network devices.

[0052] The communication in the communication system 100 can be implemented according to any appropriate (multiple) communication protocols, including but not limited to cellular communication protocols of the first generation (1G), second generation (2G), third generation (3G), fourth generation (4G) and fifth generation (5G), wireless local area network communication protocols such as Institute of Electrical and Electronics Engineers (IEEE) 802.11, and / or any other protocol currently known or to be developed in the future. In addition, the communication can utilize any appropriate wireless communication technology, including but not limited to: code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), frequency division duplex (FDD), time division duplex (TDD), multiple input multiple output (MIMO), orthogonal frequency division multiplexing (OFDM), discrete Fourier transform spread OFDM (DFT-s-OFDM) and / or any other technology currently known or to be developed in the future.

[0053] In order to make the description of the scheme of the embodiment of the present disclosure clearer, the relevant technology is first introduced below. In Rel-16 (work item "5G V2X with NR sidelink"), the PSFCH (physical sidelink feedback channel) for sidelink communication is specified to transmit HARQ (hybrid automatic repeat request) feedback from the intended recipient UE (hereinafter referred to as the receiver UE) of the PSCCH / PSSCH transmission to the UE performing the transmission (hereinafter referred to as the transmitter UE) via the sidelink (at the physical layer). The PSFCH transmits a sequence in one PRB that is repeated on two OFDM symbols (the first OFDM symbol of which can be used for AGC) near the end of the sidelink resource in the time slot. The time resources of the PSFCH are (pre) configured to appear once every 1, 2 or 4 time slots. The HARQ feedback resource (PSFCH) is derived from the resource position of the PSCCH / PSSCH. Figure 1B An example of a sidelink timeslot configuration including PSFCH resources for HARQ feedback is shown. Figure 1B As shown, an example of the time slot format of PSCCH, PSSCH and PSFCH is provided. The basic sequence is (pre)configured per sidelink resource pool.

[0054] Figure 1C An example of the Uu beam alignment process is shown. As described in 3GPP TS 38.214 Section 5.1.5 (TCI and QCL framework) and Section 5.1.6 (CSI-RS reception process), Uu beam management is defined in three phases. Figure 1C As shown, process 100-1 includes phase #1 (P1), phase #2 (P2), and phase #3 (P3). During phase #1 (P1), as shown at 101, UE 130 uses a wide Rx (receive) beam while gNB 140 is performing SS bursting, where the SSB is scanned and transmitted in different angular directions covering the cell. Referring to steps 103, 105, 107, and 109, UE 130 measures the RSRP (reference signal received power) of all SSB beams on all UE panels and sends PRACH on the RACH opportunity associated with the best SSB beam to connect to the network using the reciprocal transmit (Tx) beam of the best SSB beam. During phase #2 (P2), as shown at 111, UE 130 uses a wide Rx beam (receive beam) to receive the gNB refined DL CSI-RS beam scan within the connected SSB beam. UE 130 measures the RSRP of all CSI-RS beams and reports back the best beam ID(s) to gNB 140, still using the reciprocal wide Tx beam (transmit beam). During phase #3 (P3), as shown at 113, gNB 140 transmits repeated CSI reference signals with the selected beam based on the UE report in phase #2, and UE 130 scans the refined Rx beam settings to identify its best narrow Rx beam. At the end of P3, as shown at 115, the alignment between the gNB Tx beam and the UE Rx beam is obtained to obtain maximum directional gain.

[0055] Figure 1D An example of a possible sidelink initial beam alignment procedure is shown (inspired by Uu initial beam alignment). As stated in the standardization goal, the sidelink operation in FR2 will be a CSI-RS based procedure and try to reuse the Uu beam alignment procedure as much as possible. The most straightforward forward sidelink beam alignment inspired by the Uu interface is protected as Figure 1D shown.

[0056] In process 100-2, in the discovery process as shown in 102, for example after prose and discovery model A or B. For the case of V2x, discovery occurs at the V2x layer and is achieved by exchanging CAMs in the ITS band at 5.9 GHz. It should be noted that the discovery process can occur in FR1 or FR2. However, the benefit of doing this in FR1 is that beam-based discovery does not need to be performed. If applied in FR2, it will need to be performed using only wide beams, so discovery can be limited in coverage and take a long time for devices that can only transmit from a single panel at the time (current smartphone UE implementations). At 104, the P-UE (primary UE) 160 and the S-UE (secondary UE) 150 establish a unicast link via PC5 connection establishment. It should be noted that this can be performed at FR1 or FR2. At 106, the P-UE 160 or S-UE 150 triggers initial beam alignment. It should be noted that the trigger can occur at FR1 or FR2 and can indicate configuration details about beam alignment (e.g., the SL (sidelink) beam management reference signal (SL-BMRS) format to be used, the expected number of beam scans, the expected beam scan time period, etc.). As shown at 108, the P-UE 160 performs a wide SL-BMRS beam scan. This step is specific to FR2. The time slot format for sending these SL-BMRS for beam scanning remains open. However, in some embodiments of the present disclosure, it can be assumed that each individual SL-BMRS is sent in a single SL time slot. Therefore, if four wide beam scans are required, the P-UE 160 will have to send 4 different SL time slots, and each time slot utilizes a different beam. At 110a, the S-UE 150 reports to the P-UE 160 what is the best wide SL-BMRS beam (e.g., the index or time slot of the SL-BMRS beam received at higher power). This report can be sent in FR1 or FR2, and this corresponds to the completion of P1. As shown at 112, the P-UE 160 performs a narrow SL-BMRS beam scan. This step is specific to FR2. As in 108, it is assumed here that the scan will utilize a single SL time slot for each beam scan. At 114, the S-UE 150 reports to the P-UE 160 what is the best narrow SL-BMRS beam. This report can be sent in FR1 or FR2, which corresponds to the completion of P2. At 116, the P-UE 160 performs m repetitions of the SL-BMRS while applying the selected narrow Tx beam. The S-UE 150 performs a narrow Rx beam scan with the purpose of identifying the best narrow Rx beam.

[0057] Beam reporting is critical for many stages of SL FR2 beam management, such as initial beam pairing and beam maintenance. Regarding beam reporting, the following agreement was reached in RAN1#112bis: The (multiple) containers of sidelink beam reports for beam maintenance are selected from at least the following options: Option 1: SL PHY layer signal (e.g., PSFCH, SCI); Option 2: SLMAC CE. FFS is PC5-RRC signaling (e.g., UCI) over the Uu link. As shown in the above agreement, PSFCH is identified as an option for the sidelink beam report container. PSFCH is promising in standardization because it is a fast and resource-efficient way to provide beam reports as a SL PHY layer signal. In some schemes, it is recommended to use PSFCH to confirm whether the transmitted beam is acceptable. Reference Figure 1E and Figure 1F , Figure 1E Some examples of transmit beams at UE A and receive beams at UE B for sidelink communication are shown. Figure 1E As shown, transmit beams (a1, a2, a3, a4) are used at UE A, and receive beams (b1, b2, b3, b4) are used at UE B. UE A transmits RS (reference signal) in different directions (using different transmit beams: a1, a2, a3, a4). Figure 1F A schematic diagram of transmit beam training and corresponding beam reporting using PSFCH according to some schemes is shown. For some of the above beam reporting schemes, the Tx UE only knows which transmit beams are suitable, but does not know which transmit beam is the best.

[0058] The Tx UE transmits an RS (reference signal) to the Rx UE via different transmission beams, and the Rx UE measures the RS and then reports the measured beam information to the Tx UE so that the Tx UE will use an appropriate transmission beam for sidelink communication with the Rx UE. The following agreement regarding beam reporting was reached in RAN1#112bis: RAN1 may study the following candidate process, in which initial beam pairing is performed before the sidelink unicast link is established, including at least the following steps and how to determine UE2: UE1 sends a reference signal via different transmit beams (note that multiple reference signal transmissions from each beam may be studied (e.g., repeated). FFS: sends a reference signal, and applicable reference signals); UE2 measures the reference signal and determines the UE1 transmit beam and / or the UE2 receive beam (FFS: whether / how to determine the UE2 transmit beam); UE2 indicates to UE1 the determined UE1 transmit beam (FFS: how to indicate the determined transmit beam, including its feasibility); UE1 and UE2 establish the sidelink unicast link using the determined beam according to the conventional link establishment process.

[0059] RAN1 may study the following candidate procedures, in which initial beam pairing starts after a sidelink unicast link is established between UE1 and UE2, including studying whether initial beam pairing after the sidelink unicast link is established is feasible and under what circumstances it is feasible. UE1 and UE2 establish a sidelink unicast link according to a conventional link establishment procedure (FFS: beam for unicast link establishment). UE1 and / or UE2 configure resources for beam scanning and / or beam reporting (FFS: details of resource configuration). UE1 and / or UE2 use the configured resources to send a reference signal and determine a pair of transmit beams and receive beams based on beam scanning (FFS: (multiple) applicable reference signals, and whether / how to indicate the determined beams between UE1 and UE2, and the difference between initial beam pairing (after the sidelink unicast link is established) and beam maintenance.

[0060] Resource efficient and fast beam reporting is required to achieve proper and timely beam management. In the scheme of an embodiment of the present disclosure, enhancements to fast beam reporting for sidelink communication using PSFCH in FR2 are designed. In some embodiments, the scheme proposed in the present disclosure (e.g., a scheme for fast beam reporting via PSFCH for transmit beam training in FR2 sidelink communication) may include the key idea that, during the beam training process, in the PSFCH resources associated with the RS signal transmitted from the Tx UE using the transmit beam, the Rx UE sends a PSFCH that transmits an ACK to indicate that the transmit beam is acceptable (or referred to as available in this article) and is the best beam so far, or sends a PSFCH that transmits a NACK to indicate that the transmit beam is acceptable but not the best beam so far, or does not send (PSFCH does not exist) to indicate that the transmit beam is not acceptable. Therefore, based on the collected information, such as the best transmit beam so far, the acceptable (multiple) transmit beams, and the measured PSFCH received power, the Tx UE can select a set of suitable transmit beams. The solution proposed in this disclosure can achieve fast transmit beam training for sidelink communication in FR2 with little impact on the specification. The solution proposed in this disclosure will be further described in the following embodiments.

[0061] Reference now Figure 2 , Figure 2 2 shows a beam reporting process 200 according to some embodiments of the present disclosure. The process 200 may involve: Figure 1A The first terminal device 110 and the second device 120 are shown. It should be understood that although Figure 1AThe beam reporting process 200 is described in the system 100, but the process can also be applied to other communication scenarios. In some examples, the first terminal device 110 can be an Rx UE and the second terminal device 120 can be a Tx UE.

[0062] In process 200, the second terminal device 120 may transmit (202) at least one reference signal 205 associated with at least one of the plurality of beams to the first terminal device 110. On the first terminal device 110 side, after receiving (204) the at least one reference signal 205 associated with at least one of the plurality of beams, the first terminal device 110 may determine (206) the usability of at least one of the plurality of beams associated with the at least one reference signal 205 transmitted by the second terminal device 120 based on the measured signal level and / or quality. In some examples, the measured signal level and / or quality may be measured for a reference signal (RS) transmitted using a transmit beam.

[0063] In some examples, the signal level and / or quality may be a reference signal received power (RSRP). In order to determine the availability of at least one of the multiple beams, the first terminal device 110 may measure the signal level and / or quality of the multiple beams, and determine that at least one of the multiple beams is usable based on at least one of the multiple beams having a signal level and / or quality above a threshold. For example, if the beam has an RSRP above a threshold, the first terminal device 110 may determine that the beam is usable (or acceptable). In some examples, the signal level and / or quality of a beam may refer to a signal level and / or quality measured for a reference signal sent using the beam, for example, the RSRP of a beam may refer to the RSRP of an RS sent using the beam.

[0064] The first terminal device 110 may perform (208) a beam-wise comparison between at least one of the plurality of beams determined to be available. The beam-wise comparison may be based on measured signal levels and / or qualities for identifying at least one beam having the most suitable signal level and / or quality for signal transmission. In order to identify at least one beam having the most suitable signal level and / or quality for signal transmission, the first terminal device 110 may store the measured signal levels and / or qualities and additionally or alternatively store the determined availability so as to use one or both of them to identify at least one beam having the most suitable signal level and / or quality for signal transmission. For example, the first terminal device 110 may store the measured RSRP of the plurality of beams. The first terminal device 110 may also store the availability of the plurality of beams, for example, whether the beams are available (or acceptable).

[0065] To perform a beam-by-beam comparison for identifying at least one beam, the first terminal device 110 may determine that the at least one beam has the most suitable signal level and / or quality for signal transmission based on a signal level and / or quality of the at least one beam being greater than a signal level and / or quality of other beams in the plurality of beams. For example, based on an RSRP of the beam being greater than a recorded maximum RSRP, the first terminal device 110 may determine that the beam has the most suitable RSRP for signal transmission.

[0066] In some embodiments, the first terminal device 110 may record at least one transmit beam having the most suitable signal level and / or quality for signal transmission as at least one optimal transmit beam, and additionally or alternatively, record at least one receive beam associated with the most suitable signal level and / or quality as at least one optimal receive beam.

[0067] Figure 2 The beams mentioned in may be (multiple) transmit beams. For example, at least one beam may be at least one transmit beam, and the multiple beams may be multiple transmit beams. In some other embodiments, in order to perform a beam-by-beam comparison for identifying at least one beam, the first terminal device 110 may determine that at least one transmit beam has the most suitable signal level and / or quality for signal transmission based on the following conditions: a pattern of the transmit beam scan indicates that at least one transmit beam is recorded as at least one optimal transmit beam, but at least one receive beam corresponding to the at least one transmit beam is not recorded as at least one optimal receive beam. Examples of these embodiments may be further referenced. Figure 4 .

[0068] The first terminal device 110 may then send (210) an indication 215 to the second terminal device 120, the indication 215 indicating at least one beam having the most suitable signal level and / or quality, and additionally or alternatively indicating that at least one beam of the plurality of beams is available. In some examples, the first terminal device 110 may send an acknowledgement (ACK) on a physical sidelink feedback channel resource for at least one reference signal transmission using at least one beam, the acknowledgement indicating at least one beam available and having the most suitable signal level and / or quality for signal transmission. In some other examples, the first terminal device 110 may send a negative acknowledgement (NACK) on a physical sidelink feedback channel resource for at least one reference signal transmission using at least one beam of the plurality of beams, the negative acknowledgement indicating that at least one beam of the plurality of beams is available and does not have the most suitable signal level and / or quality for signal transmission. In some other examples, the first terminal device 110 may avoid sending on a physical sidelink feedback channel resource for at least one reference signal transmission using at least one beam of the plurality of beams based on the unavailability of at least one beam of the plurality of beams. For example, if the beam is unavailable, the first terminal device 110 sends neither ACK nor NACK.

[0069] For the indication 215 sent by the first terminal device 110, on the second terminal device 120 side, the second terminal device 120 can receive (212) the indication 215. In some examples, in order to receive the indication 215, the second terminal device 120 can monitor the indication 215 from the first terminal device 110. In some examples, the second terminal device 120 can determine that at least one beam is available and has the most suitable signal level and / or quality for signal transmission based on receiving an acknowledgement on a physical sidelink feedback channel resource for reference signal transmission using at least one beam. In some other examples, the second terminal device 120 can determine that at least one beam of the multiple beams is available and does not have the most suitable signal level and / or quality for signal transmission based on receiving a negative acknowledgement on a physical sidelink feedback channel resource for reference signal transmission using at least one beam of the multiple beams. In some other examples, the second terminal device 120 may determine that at least one of the multiple beams is unavailable based on receiving neither an acknowledgment nor a negative acknowledgment on a physical sidelink feedback channel resource for transmitting a reference signal using at least one of the multiple beams.

[0070] The second terminal device 120 may determine (214) one or more beams of at least one of the plurality of beams for signal transmission based on monitoring. In some examples, the second terminal device 120 may measure at least one received power of a physical sidelink feedback channel associated with at least one of the available plurality of beams, the received power of the physical sidelink feedback channel being used to transmit the indication, and then determine an absolute difference or a relative difference between: at least one received power of the physical sidelink feedback channel associated with at least one of the available plurality of beams, and at least one received power of the physical sidelink feedback channel associated with at least one beam having the most suitable signal level and / or quality.

[0071] In addition, the second terminal device 120 may determine one or more beams of at least one of the multiple beams for signal transmission based on an absolute difference or a relative difference. For example, based on the collected information, such as the best transmit beam to date (an example of a beam with the most suitable signal level and / or quality), (multiple) acceptable transmit beams (an example of (multiple) available beams), and the measured PSFCH received power (i.e., an example of the received power of the physical sidelink feedback channel associated with the beam), the second terminal device 120 may select a set of suitable transmit beams for signal transmission. In some examples, if the received power (P SSFCH) of the acceptable transmit beam is confirmed to be i ) and the received power (P o ) is less than the (pre-)configured power difference threshold, the second terminal device 120 may determine the acceptable transmit beam as a suitable beam. These details may be further referred to in the following embodiments.

[0072] Note that in the embodiment of the present disclosure, a terminal device as the second terminal device 120 uses a beam to send a reference signal, and accordingly, a terminal device as the first terminal device 110 sends an indication 215 on a feedback resource associated with a reference information 205. For example, a Tx UE sends a reference signal 205 using a beam, and an Rx UE sends an indication 215 on a feedback resource associated with the reference information. The indication 215 indicates the quality of the beam. The feedback resource may be a physical sidelink feedback channel (PSFCH) resource.

[0073] With reference to some of the above embodiments, the Tx UE may be used as an example of the second terminal device 120, and the Rx UE may be used as an example of the first terminal device 110. In some examples, in a PSFCH resource associated with an RS signal transmitted from the Tx UE using a transmit beam, the Rx UE transmits a PSFCH for transmitting an ACK to indicate that the transmit beam is acceptable and is the best beam so far, or transmits a PSFCH for transmitting a NACK to indicate that the transmit beam is acceptable but not the best beam so far, or does not transmit (PSFCH does not exist) to indicate that the transmit beam is not acceptable. In some other examples, based on a transmit beam scanning pattern, if the transmit beam is the best beam so far, but the receive beam is not the best beam, the Rx UE may transmit a PSFCH for transmitting an ACK to provide diversity of the PSFCH transmission for transmitting an ACK to increase the chance that the Tx UE detects the PSFCH for transmitting an ACK. The Rx UE may transmit the PSFCH via the recorded best receive beam to improve the link level performance of the PSFCH transmission. Therefore, based on the collected information: the best transmit beam so far, (multiple) acceptable transmit beams, and the measured PSFCH received power, the Tx UE selects a set of appropriate transmit beams. i ) and the received power (P o ) is less than the (pre) configured power difference threshold, the Tx UE can determine the acceptable transmit beam as a suitable beam.

[0074] Some embodiments of detailed operations at the Tx UE and the Rx UE are described as follows. First, the transmission beam training process at the Rx UE (eg, Figure 1E Operations at UE B) in .

[0075] Using the receive beam (beam b j ), the Rx UE measures the transmission beam (beam a) from the Tx UE (e.g., UE A) i ) The RSRP of the RS transmitted. If the RSRP of the RS is higher than a threshold that can be configured (or pre-configured), the Rx UE can transmit the beam (a i ) is marked or recorded as acceptable. The transmit beam is acceptable if the transmit beam can be used for signal transmission, that is, the acceptable beam can be called an available beam.

[0076] The Rx UE can then check the acceptable transmit beam (a i) is the best transmit beam so far. Specifically, if the transmit beam is the first beam recorded as an acceptable beam during the transmit beam training process, the Rx UE may identify or record the transmit beam as the best transmit beam so far (a o ), and record the RSRP of RS as the maximum RSRP (RSRP m Based on the above situation, in some embodiments, the Rx UE may record the receiving beam as the best receiving beam (b o ). refer to Figure 1E and Figure 3 or Figure 4 , RS transmits with transmit beam a2 and receives with receive beam b1. Figure 3 and Figure 4 In FIG. 1 , the transmission beams represented by the striped pattern represent acceptable transmission beams, and the other transmission beams represented by the gray color represent unacceptable transmission beams. It can be seen that the transmission beam a2 is the first acceptable transmission beam, so the Rx UE can identify or record the transmission beam a2 as the best transmission beam so far (a o ), and record the RSRP of RS as the maximum RSRP (RSRP m ). In addition, the Rx UE may send a PSFCH for transmission confirmation (ACK), such as Figure 3 or Figure 4 PSFCH 2,1 :ACK.

[0077] If the transmit beam is not the first beam recorded as an acceptable beam during the transmit beam training process, the Rx UE may compare the RSRP with the recorded maximum RSRP. If the RSRP is greater than the recorded maximum RSRP, the Rx UE may identify or record the transmit beam as the best transmit beam so far (a o ), and record RSRP as the maximum RSRP (RSRP m In this case, in some embodiments, the Rx UE may record the receiving beam as the best receiving beam (b o ). refer to Figure 1E An example can be described as Figure 1E As shown, for example, if the RS is transmitted with transmit beam a3 and received with receive beam b1, and the RSRP of the RS is greater than the recorded maximum RSRP, the RSRP of the RS will be recorded as the new maximum RSRP. In this case, in some examples, transmit beam a3 can be recorded as the best transmit beam a so far. o Additionally or alternatively, the receive beam b1 may be recorded as the best receive beam b o .

[0078] In some embodiments, in a PSFCH resource associated with an RS signal, if a transmit beam (a i ) is acceptable and is the best transmit beam so far (a i =a o ), and if the corresponding receiving beam is the best receiving beam (b j =b o ), the Rx UE may send a PSFCH of a transmission confirmation (ACK). In some examples, if the correspondence between the Tx beam and the Rx beam is assumed, the Rx UE may transmit the PSFCH of the transmission confirmation (ACK) via beam b. j Send PSFCH. Figure 1E and Figure 3 For example, when the RS transmits with transmit beam a3 and receives with receive beam b1, the RSRP is recorded as the maximum RSRP, and transmit beam a3 is recorded as the best transmit beam a so far. o , and the receiving beam b1 is recorded as the best receiving beam b o In this case, the Rx UE may send a PSFCH conveying an ACK (see Figure 3 PSFCH shown 3,1 :ACK). Figure 3 As shown, after the transmit beam training process is completed, the Rx UE receives the PSFCH 3,1 (ACK) identifies a3 as the best transmit beam and a2 and a4 as acceptable transmit beams.

[0079] In some embodiments, if the transmitted beam (a i ) is acceptable and is the best transmit beam so far (a i =a o ), and if the corresponding receiving beam is not the best receiving beam (b j ≠b o ), the Rx UE may send a PSFCH to transmit a NACK. Figure 1E and Figure 3 , when another RS ​​transmits with transmit beam a3 and receives with receive beam b2. As described above, transmit beam a3 is recorded as the best transmit beam a so far. o , but the receiving beam b2 is not identified or recorded as the best receiving beam b o In this case, the Rx UE may send a PSFCH that conveys a NACK (see Figure 3 PSFCH shown 3,2 :NACK).

[0080] In some other embodiments, if the transmitted beam (a i) is acceptable and is the best transmit beam so far (a i =a o ), and if the corresponding receiving beam is not the best receiving beam (b j ≠b o ), and if the Tx UE only needs to know the best transmit beam, the Rx UE can send the PSFCH for ACK even if the receive beam is not identified or recorded as the best receive beam. This will provide diversity in the PSFCH transmission for ACK to increase the chance of the Tx UE detecting the PSTCH for ACK. If the Tx / Rx beam correspondence is assumed, the Rx UE can transmit the PSFCH for ACK via b j Alternatively, the Rx UE can also transmit PSFCH via b o This will improve the link level performance of PSFCH transmission. In these embodiments, the transmit beam (a i ) may be determined as the best transmit beam so far based on a transmit beam scanning pattern known to the Rx UE or detected at the Rx UE (a i =a o ). The transmit beam scanning pattern may indicate: via which transmit beam the RS signal is transmitted, or whether two RS signals are transmitted via the same transmit beam. Figure 1E and Figure 4 , when the RS transmits with transmit beam a3 and receives with receive beam b1, the RSRP is recorded as the maximum RSRP, and transmit beam a3 is recorded as the best transmit beam a so far. o , and the receiving beam b1 is recorded as the best receiving beam b o , Rx-UE can send PSFCH to transmit ACK (see Figure 4 PSFCH shown 3,1 :ACK). When another RS ​​transmits with transmit beam a3 and receives with receive beam b2. As described above, transmit beam a3 is recorded as the best transmit beam a so far. o , but the receiving beam b2 is not recorded as the best receiving beam b o In this case, based on the transmit beam scanning pattern, the Rx UE may know that the above additional RS is transmitted with the best transmit beam so far, or know that the above additional RS is transmitted with the same transmit beam as the transmit beam used to transmit the above RS, then the Rx UE may send a PSFCH for transmitting ACK (see Figure 4 PSFCH shown 3,2 :ACK). Similarly, PSFCH 3,4 Send ACK. Rx UE can transmit ACK via b o(b1) Sending PSFCH 3,2 and PSFCH 3,4 After the transmit beam training process is completed, UE A sends the PSFCH 3,1 (ACK) identifies a3 as the best transmit beam and a2 and a4 as acceptable transmit beams.

[0081] In some embodiments, if the transmitted beam (a i ) is acceptable and is not the best transmit beam so far (a i ≠a o ), the Rx UE may send a PSFCH to transmit a NACK. Figure 1E and Figure 3 or Figure 4 , when the RS transmits with transmit beam a4 and receives with receive beam b1, transmit beam a4 is acceptable and is not recorded as the best transmit beam so far. In this case, the Rx UE may send a PSFCH conveying NACK (see Figure 3 or Figure 4 PSFCH shown 4,1 :NACK). In some examples, if the correspondence between the Tx beam and the Rx beam is assumed, the Rx UE can transmit the signal via b j Send PSFCH.

[0082] In some embodiments, if the transmitted beam (a i ) is not acceptable, the Rx UE does not send PSFCH. Figure 1E and Figure 3 or Figure 4 For example, when the RS transmits with transmit beam a1 and is received with receive beam b1, the RSRP of the RS is not higher than the threshold, so transmit beam a1 is not acceptable (ie, unavailable), in which case the Rx UE will not transmit any PSFCH.

[0083] On the top Figure 3 and Figure 4 In the case of a delay, an indication that the transmit beam is acceptable and the best beam so far, or is acceptable but not the best beam so far, or is not acceptable may be in the next set of time slots. For example, transmit beam a2 is acceptable and the best transmit beam in P1 may be indicated at P2, as shown at P2, i.e., PSFCH 2,1 :ACK.

[0084] The following describes the transmission beam training process in the Tx UE (for example, Figure 1E Operations at UE A) in .

[0085] Tx UE can use transmit beam (beam a i ) to transmit RS. In the PSFCH resource associated with the RS signal, the Tx UE can attempt to detect the PSFCH transmitted from the Rx UE. If the correspondence between the Tx beam and the Rx beam is assumed, the Tx UE can use beam a i As the beam for PSFCH detection (reception). In some examples, if ACK is detected, the Tx UE can identify or record that the transmit beam is acceptable and is the best beam so far. In some examples, if NACK is detected, the Tx UE can identify or record that the transmit beam is acceptable and is not the best beam so far. In some examples, if no PSFCH is detected, the Tx UE can identify or record that the transmit beam is not acceptable.

[0086] In some embodiments, the Tx UE may measure or record the received power of the PSFCH. Based on the recorded information, such as the best transmit beam to date, (multiple) acceptable transmit beams, and the received power of the PSFCH, the Tx UE may select a set of suitable transmit beams. Specifically, in some embodiments, if the received power (P) of the PSFCH of the acceptable transmit beam is confirmed to be i ) and the received power (P o ) is less than the (pre-)configured power difference threshold, the Tx UE may determine the acceptable transmit beam as a suitable beam. In some other embodiments, the relative difference may be used by the Tx UE to select a set of suitable transmit beams. For example, the relative difference may be |P i -P o | / P o , and if |P i -P o | / P o ≤γ (γ is a (pre-)configured threshold), the Tx UE may determine the acceptable transmit beam as a suitable beam. The above steps may be performed after the transmit beam training process is completed or in the middle of the transmit beam training process.

[0087] Figure 5 FIG. 1 is a flowchart showing the operation of beam reporting at an Rx UE according to some embodiments of the present disclosure. Figure 5 As shown, in process 500, in step 501, the transmission beam training begins. In step 503, the receiving beam (b j ), the Rx UE can measure the transmitted beam (a i) to transmit the RSRP of the RS. In step 505, the Rx UE determines whether the RSRP is greater than a (pre)configured threshold. If yes, step 507 is executed, and if no, step 503 is continued. In step 507, the Rx UE transmits beam (a i ) is marked or recorded as acceptable. In step 509, the Rx UE determines whether the transmit beam is the first beam recorded as acceptable. If yes, step 513 is executed, and if no, step 511 is executed. In step 511, the Rx UE determines whether the RSRP is greater than the RSRP m (recorded maximum RSRP). If yes, proceed to step 513, if no, proceed to step 515. In step 513, the Rx UE may identify the transmit beam as the best transmit beam so far (a o ) and record RSRP as RSRP m After step 513, step 521 is executed. In step 521, the Rx UE may j ) is recorded as the best receiving beam (b o ). In step 523, the Rx UE may transmit the j Send a PSFCH that transmits an ACK. In step 515, the RxUE may determine whether a i =a o If yes, then execute step 517, if no, then execute step 519. In step 517, the Rx UE may transmit the data to the Rx UE via b j or via b o Send PSFCH with NACK or ACK. In step 519, the Rx UE can j Send PSFCH with NACK.

[0088] Figure 6 A flow chart of a method implemented at a first terminal device 110 according to some embodiments of the present disclosure is shown. In the method 600, at box 610, the first terminal device 110 may determine the availability of at least one beam of a plurality of beams associated with at least one reference signal transmitted by a second terminal device 120 based on a measured signal level and / or quality. At box 620, the first terminal device 110 may perform a beam-by-beam comparison between at least one beam of a plurality of beams determined to be available, wherein the beam-by-beam comparison is based on the measured signal level and / or quality for identifying at least one beam with the most suitable signal level and / or quality for signal transmission. At box 630, the first terminal device 110 may send an indication to the second terminal device 120 indicating at least one of the following: at least one beam with the most suitable signal level and / or quality; or at least one beam of a plurality of beams is available.

[0089] In some embodiments, in order to determine the availability of at least one beam among the multiple beams, the first terminal device 110 may measure the signal level and / or quality of the multiple beams, and determine that at least one beam among the multiple beams is available based on at least one beam among the multiple beams having a signal level and / or quality above a threshold.

[0090] In some embodiments, the first terminal device 110 may store the measured signal level and / or quality, or the determined availability, or both, for use in identifying at least one beam having the most suitable signal level and / or quality for signal transmission.

[0091] In some embodiments, in order to perform a beam-by-beam comparison for identifying at least one beam, the first terminal device 110 may determine that at least one beam has the most suitable signal level and / or quality for signal transmission based on the signal level and / or quality of at least one beam being greater than the signal level and / or quality of other beams in the plurality of beams.

[0092] In some embodiments, the at least one beam is at least one transmit beam. The first terminal device 110 may record at least one transmit beam having the most suitable signal level and / or quality for signal transmission as at least one optimal transmit beam, or record at least one receive beam associated with the most suitable signal level and / or quality as at least one optimal receive beam, or a combination thereof.

[0093] In some embodiments, the at least one beam is at least one transmit beam, and the plurality of beams are a plurality of transmit beams. To perform a beam-by-beam comparison for identifying the at least one beam, the first terminal device 110 may determine that the at least one transmit beam has the most suitable signal level and / or quality for signal transmission based on the following conditions: a pattern of the transmit beam scan indicates that the at least one transmit beam is recorded as at least one best transmit beam, but at least one receive beam corresponding to the at least one transmit beam is not recorded as at least one best receive beam.

[0094] In some embodiments, in order to send the indication, the first terminal device 110 may send a confirmation on a physical sidelink feedback channel resource for at least one reference signal transmission using at least one beam, the confirmation indicating at least one beam that is available and has the most suitable signal level and / or quality for signal transmission.

[0095] In some embodiments, in order to send the indication, the first terminal device 110 sends a negative acknowledgement on a physical sidelink feedback channel resource for at least one reference signal transmission using at least one of the multiple beams, the negative acknowledgement indicating that at least one of the multiple beams is available and does not have the most suitable signal level and / or quality for signal transmission.

[0096] In some embodiments, the first terminal device 110 may avoid transmitting on physical sidelink feedback channel resources for at least one reference signal transmission using at least one of the multiple beams based on the unavailability of at least one of the multiple beams.

[0097] In some embodiments, the signal level and / or quality is referenced to signal received power.

[0098] Figure 7 A flow chart of a method implemented at a second terminal device 120 according to some embodiments of the present disclosure is shown. In the method 700, at block 710, the second terminal device 120 may send at least one reference signal associated with at least one of the plurality of beams to the first terminal device 110. At block 720, the second terminal device 120 may monitor from the first terminal device 110 an indication indicating at least one of the following: at least one beam having the most suitable signal level and / or quality among the plurality of beams; or at least one beam among the plurality of beams is available. At block 730, the second terminal device 120 may determine one or more beams of at least one of the plurality of beams for signal transmission based on the monitoring.

[0099] In some embodiments, the second terminal device 120 may determine that at least one beam is available and has the most suitable signal level and / or quality for signal transmission based on receiving an acknowledgement on a physical sidelink feedback channel resource for reference signal transmission using at least one beam.

[0100] In some embodiments, the second terminal device 120 may determine that at least one of the multiple beams is available and does not have the most suitable signal level and / or quality for signal transmission based on receiving a negative acknowledgement on a physical sidelink feedback channel resource for a reference signal transmission using at least one of the multiple beams.

[0101] In some embodiments, the second terminal device 120 may determine that at least one of the multiple beams is unavailable based on receiving neither an acknowledgment nor a negative acknowledgment on a physical sidelink feedback channel resource for transmitting a reference signal using at least one of the multiple beams.

[0102] In some embodiments, in order to determine one or more beams of at least one of the multiple beams for signal transmission, the second terminal device 120 may measure at least one received power of a physical sidelink feedback channel associated with at least one of the available multiple beams, the received power of the physical sidelink feedback channel being used to transmit an indication, determine the absolute difference or relative difference between: at least one received power of a physical sidelink feedback channel associated with at least one of the available multiple beams, and at least one received power of a physical sidelink feedback channel associated with at least one beam having the most suitable signal level and / or quality; and determine one or more beams of at least one of the multiple beams for signal transmission based on the absolute difference or the relative difference.

[0103] In some embodiments, the signal level and / or quality may be a reference signal received power.

[0104] In some embodiments, an apparatus capable of executing any one of the methods 600 (e.g., the first terminal device 110) may include a component for executing the corresponding steps of the method 600. The component may be implemented in any suitable form. For example, the component may be implemented in a circuit system or a software module.

[0105] In some embodiments, the apparatus includes components for determining the availability of at least one of a plurality of beams associated with at least one reference signal sent by a second terminal device 120 based on measured signal levels and / or qualities; components for performing a beam-by-beam comparison between at least one of a plurality of beams determined to be available, wherein the beam-by-beam comparison is based on the measured signal levels and / or qualities for identifying at least one beam having the most suitable signal level and / or quality for signal transmission; and components for sending an indication to the second terminal device 120 indicating at least one of the following: at least one beam having the most suitable signal level and / or quality; or at least one of the plurality of beams is available.

[0106] In some embodiments, the component for determining the availability of at least one of the multiple beams includes a component for measuring the signal level and / or quality of the multiple beams; and a component for determining that at least one of the multiple beams is available based on at least one of the multiple beams having a signal level and / or quality above a threshold.

[0107] In some embodiments, the apparatus further comprises means for storing at least one of the following for use in identifying at least one beam having the most suitable signal level and / or quality for signal transmission: a measured signal level and / or quality; or a determined availability.

[0108] In some embodiments, means for performing a beam-by-beam comparison for identifying at least one beam includes means for determining that at least one beam has a most suitable signal level and / or quality for signal transmission based on the signal level and / or quality of the at least one beam being greater than the signal levels and / or qualities of other beams in the plurality of beams.

[0109] In some embodiments, at least one beam is at least one transmit beam, and the apparatus further comprises means for recording at least one transmit beam having the most suitable signal level and / or quality for signal transmission as at least one optimal transmit beam; or means for recording at least one receive beam associated with the most suitable signal level and / or quality as at least one optimal receive beam.

[0110] In some embodiments, the at least one beam is at least one transmit beam and the plurality of beams are a plurality of transmit beams. The means for performing a beam-by-beam comparison for identifying the at least one beam includes means for determining that the at least one transmit beam has a most suitable signal level and / or quality for signal transmission based on the following condition: the pattern of the transmit beam scan indicates that the at least one transmit beam is recorded as at least one best transmit beam, but at least one receive beam corresponding to the at least one transmit beam is not recorded as at least one best receive beam.

[0111] In some embodiments, the means for sending an indication includes means for sending an acknowledgment on a physical sidelink feedback channel resource for at least one reference signal transmission using at least one beam, the acknowledgment indicating at least one beam that is available and has the most suitable signal level and / or quality for signal transmission.

[0112] In some embodiments, the means for sending an indication includes means for sending a negative acknowledgment on a physical sidelink feedback channel resource for at least one reference signal transmission using at least one of the multiple beams, the negative acknowledgment indicating that at least one of the multiple beams is available and does not have the most suitable signal level and / or quality for signal transmission.

[0113] In some embodiments, the apparatus further comprises means for avoiding transmission on physical sidelink feedback channel resources for at least one reference signal transmission using at least one of the plurality of beams based on at least one of the plurality of beams being unavailable.

[0114] In some embodiments, the signal level and / or quality is referenced to signal received power.

[0115] In some embodiments, the apparatus further comprises means for performing other steps of some embodiments of method 600. In some embodiments, the means comprises at least one processor; and at least one memory comprising computer program code, the at least one memory and the computer program code being configured to cause the above-mentioned operation of the apparatus together with the at least one processor.

[0116] In some embodiments, a device capable of executing any one of the methods 700 (e.g., the second terminal device 120) may include a component for executing the corresponding steps of the method 700. The component may be implemented in any suitable form. For example, the component may be implemented in a circuit system or a software module.

[0117] In some embodiments, the apparatus includes components for sending at least one reference signal associated with at least one of the multiple beams to the first terminal device 110; components for monitoring from the first terminal device 110 an indication indicating at least one of the following: at least one beam having the most suitable signal level and / or quality among the multiple beams; or at least one beam among the multiple beams is available; and components for determining one or more beams of at least one of the multiple beams for signal transmission based on the monitoring.

[0118] In some embodiments, the means for monitoring the indication includes means for determining that at least one beam is available and has the most appropriate signal level and / or quality for signal transmission based on receiving an acknowledgement on a physical sidelink feedback channel resource for reference signal transmission using at least one beam.

[0119] In some embodiments, the component for monitoring the indication includes a component for determining that at least one of the multiple beams is available and does not have the most suitable signal level and / or quality for signal transmission based on receiving a negative acknowledgement on a physical sidelink feedback channel resource for a reference signal transmission using at least one of the multiple beams.

[0120] In some embodiments, the apparatus further comprises means for determining that at least one of the plurality of beams is unavailable based on receiving neither an acknowledgement nor a negative acknowledgement on a physical sidelink feedback channel resource for reference signal transmission using at least one of the plurality of beams.

[0121] In some embodiments, the components for determining one or more beams of at least one of the multiple beams for signal transmission include components for measuring at least one received power of a physical sidelink feedback channel associated with at least one of the available multiple beams, the received power of the physical sidelink feedback channel being used to transmit an indication; components for determining an absolute difference or a relative difference between: at least one received power of a physical sidelink feedback channel associated with at least one of the available multiple beams, and at least one received power of a physical sidelink feedback channel associated with at least one beam having a most suitable signal level and / or quality; and components for determining one or more beams of at least one of the multiple beams for signal transmission based on the absolute difference or the relative difference.

[0122] In some embodiments, the signal level and / or quality is referenced to signal received power.

[0123] In some embodiments, the apparatus further comprises means for performing other steps in some embodiments of method 700. In some embodiments, the means comprises at least one processor; and at least one memory comprising computer program code, the at least one memory and the computer program code being configured to cause the above-mentioned operations of the apparatus together with the at least one processor.

[0124] Figure 8 800 is a simplified block diagram of a device 800 suitable for implementing an embodiment of the present disclosure. The device 800 may be provided to implement a communication device, such as Figure 1A The first terminal device 110 or the second terminal device 120 is shown. As shown in the figure, the device 800 includes one or more processors 810, one or more memories 820 coupled to the processor 810, and one or more communication modules 840 coupled to the processor 810.

[0125] The communication module 840 is used for two-way communication. The communication module 840 has at least one antenna to facilitate communication. The communication interface may represent any interface necessary for communication with other network elements.

[0126] Processor 810 may be of any type suitable for the local technology network, and may include, as non-limiting examples, one or more of a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. Device 800 may have multiple processors, such as application specific integrated circuit chips that are time slaved to a clock synchronized with a main processor.

[0127] The memory 820 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) 824, electrically programmable read-only memory (EPROM), flash memory, hard disks, compact disks (CDs), digital video disks (DVDs), and other magnetic storage devices and / or optical storage devices. Examples of volatile memories include, but are not limited to, random access memory (RAM) 822 and other volatile memories that do not persist during power outages.

[0128] The computer program 830 includes computer executable instructions that are executed by the associated processor 810. The program 830 may be stored in the ROM 824. The processor 810 may perform any suitable actions and processes by loading the program 830 into the RAM 822.

[0129] The embodiments of the present disclosure may be implemented by a program 830, so that the device 800 may execute the reference Figures 2 to 7 Any process of the present disclosure discussed. The embodiments of the present disclosure may also be implemented by hardware or a combination of software and hardware.

[0130] In some embodiments, the program 830 may be tangibly contained in a computer-readable medium, which may be included in the device 800 (such as in the memory 820) or in other storage devices accessible to the device 800. The device 800 may load the program 830 from the computer-readable medium to the RAM 822 for execution. The computer-readable medium may include any type of tangible non-volatile memory, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. Fig. 9 An example of a computer readable medium 900 in the form of a CD or DVD is shown. The computer readable medium has a program 830 stored thereon.

[0131] Generally, various embodiments of the present disclosure may be implemented using hardware or dedicated circuits, software, logic, or any combination thereof. Some aspects may be implemented using hardware, while other aspects may be implemented using firmware or software that may be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure are illustrated and described as block diagrams, flow charts, or using some other graphical representations, it should be understood that, as non-limiting examples, the blocks, devices, systems, techniques, or methods described herein may be implemented using hardware, software, firmware, dedicated circuits or logic, general-purpose hardware or controllers or other computing devices, or some combination thereof.

[0132] The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer executable instructions, such as instructions included in a program module, which are executed in a device on a target real or virtual processor to perform the above reference Figure 2-Figure 7 Method 600 or method 700 described. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform specific tasks or implement specific abstract data types. In various embodiments, the functions of program modules can be combined or split between program modules as needed. The machine executable instructions of program modules can be executed in local or distributed devices. In distributed devices, program modules can be located in both local and remote storage media.

[0133] The program code for executing the disclosed method can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer or other programmable data processing device so that the program code causes the function / operation specified in the flow chart and / or block diagram to be realized when executed by the processor or controller. The program code can be executed completely on the machine, partially on the machine, as an independent software package, partially on the machine and partially on a remote machine, or completely on a remote machine or server.

[0134] In the context of the present disclosure, computer program codes or related data may be carried by any suitable carrier to enable a device, apparatus or processor to perform various processes and operations as described above. Examples of carriers include signals, computer readable media, etc.

[0135] Computer readable medium can be a computer readable signal medium or a computer readable storage medium. Computer readable medium can include but is not limited to electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. More specific examples of computer readable storage medium will include electrical connections with one or more wires, portable computer floppy disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing. The term "non-transient" used herein is a restriction on the medium itself (i.e., tangible, rather than signal), rather than a restriction on data storage persistence (e.g., RAM and ROM).

[0136] In addition, although the operations are described in a particular order, this should not be understood as requiring such operations to be performed in the particular order shown or in order or performing all the operations shown to obtain the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the above discussion, these should not be interpreted as limitations on the scope of the present disclosure, but rather descriptions of features that may be specific to a particular embodiment. Certain features described in the context of a separate embodiment may also be implemented in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable sub-combination.

[0137] Although the present disclosure has been described in language specific to structural features and / or methodological acts, it should be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Instead, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A first terminal device, comprising: at least one processor; as well as at least one memory storing instructions, wherein when the instructions are executed by the at least one processor, the first terminal device at least: determining, based on the measured signal level and / or quality, availability of at least one beam of the plurality of beams associated with at least one reference signal transmitted by the second terminal device; performing a beam-by-beam comparison between the at least one beam of the plurality of beams determined to be available, wherein the beam-by-beam comparison is based on the measured signal level and / or quality for identifying at least one beam having a most suitable signal level and / or quality for signal transmission; as well as An indication is sent to the second terminal device indicating at least one of the following: the at least one beam having the most suitable signal level and / or quality; or the at least one beam among the multiple beams is available.

2. The first terminal device according to claim 1, wherein the first terminal device is caused to determine the availability of the at least one beam in the plurality of beams by: measuring signal levels and / or qualities of the plurality of beams; and Based on the at least one beam in the plurality of beams having the signal level and / or quality above a threshold, it is determined that the at least one beam in the plurality of beams is available.

3. The first terminal device according to claim 1 or 2, wherein the first terminal device is further configured to: storing at least one of the following for use in identifying the at least one beam having the most suitable signal level and / or quality for transmission of the signal: said measured signal level and / or quality; or The availability determined.

4. The first terminal device according to any one of claims 1 to 3, wherein the first terminal device is caused to perform the beam-by-beam comparison for identifying the at least one beam by: Based on the signal level and / or quality of the at least one beam being greater than the signal levels and / or qualities of other beams in the plurality of beams, it is determined that the at least one beam has the most suitable signal level and / or quality for the signal transmission.

5. The first terminal device according to claim 4, wherein the at least one beam is at least one transmit beam, and the first terminal device is further configured to at least one of the following: recording the at least one transmission beam having the most suitable signal level and / or quality for the signal transmission as at least one optimal transmission beam; or At least one receiving beam associated with the most suitable signal level and / or quality is recorded as at least one best receiving beam.

6. The first terminal device according to any one of claims 1 to 3, wherein the at least one beam is at least one transmit beam, the plurality of beams are a plurality of transmit beams, and the first terminal device is caused to perform the beam-by-beam comparison for identifying the at least one beam by: Determining that the at least one transmit beam has the most suitable signal level and / or quality for the signal transmission based on the following conditions: The pattern of the transmission beam scanning indicates that the at least one transmission beam is recorded as at least one optimal transmission beam, but at least one reception beam corresponding to the at least one transmission beam is not recorded as at least one optimal reception beam.

7. The first terminal device according to any one of claims 1 to 6, wherein the first terminal device is caused to send the indication by: An acknowledgement is sent on a physical sidelink feedback channel resource used for at least one reference signal transmission using the at least one beam, the acknowledgement indicating that the at least one beam is available and has the most suitable signal level and / or quality for the signal transmission.

8. The first terminal device according to any one of claims 1 to 3, wherein the first terminal device is caused to send the indication by: A negative acknowledgement is sent on a physical sidelink feedback channel resource used for at least one reference signal transmission using at least one of the multiple beams, the negative acknowledgement indicating that the at least one of the multiple beams is available and does not have the most suitable signal level and / or quality for the signal transmission.

9. The first terminal device according to any one of claims 1 to 3, wherein the first terminal device is further configured to: Based on the at least one beam among the multiple beams being unavailable, avoiding transmission on a physical sidelink feedback channel resource used for at least one reference signal transmission using the at least one beam among the multiple beams.

10. The first terminal device according to any one of claims 1 to 7, wherein the signal level and / or quality is a reference signal received power.

11. A second terminal device, comprising: at least one processor; as well as at least one memory storing instructions, wherein when the instructions are executed by the at least one processor, the second terminal device at least: sending at least one reference signal associated with at least one beam of the plurality of beams to a first terminal device; monitoring from the first terminal device for an indication indicating at least one of: at least one beam in the plurality of beams having a most suitable signal level and / or quality; or the at least one beam in the plurality of beams being available; as well as Based on the monitoring, one or more beams of the at least one beam of the plurality of beams are determined for signal transmission.

12. The second terminal device according to claim 11, wherein the second terminal device is caused to monitor the indication by: Based on receiving an acknowledgement on a physical sidelink feedback channel resource, it is determined that the at least one beam is available and has the most suitable signal level and / or quality for the signal transmission, and the physical sidelink feedback channel resource is used for reference signal transmission using the at least one beam.

13. The second terminal device according to claim 11, wherein the second terminal device is caused to monitor the indication by: Based on receiving a negative acknowledgement on a physical sidelink feedback channel resource, it is determined that at least one of the multiple beams is available and does not have the most suitable signal level and / or quality for the signal transmission, and the physical sidelink feedback channel resource is used for reference signal transmission using the at least one of the multiple beams.

14. The second terminal device according to claim 11, wherein the second terminal device is further configured to: Based on neither receiving an acknowledgment nor a negative acknowledgment on a physical sidelink feedback channel resource, determining that at least one of the multiple beams is unavailable, and the physical sidelink feedback channel resource is used for reference signal transmission using the at least one of the multiple beams.

15. The second terminal device according to any one of claims 11 to 14, wherein the second terminal device is caused to determine the one or more beams of the at least one beam of the plurality of beams used for signal transmission by: measuring at least one received power of a physical sidelink feedback channel associated with at least one of the available plurality of beams, the received power of the physical sidelink feedback channel being used to communicate the indication; determining an absolute or relative difference between: at least one received power of a physical sidelink feedback channel associated with said at least one beam of said plurality of beams being available and at least one received power of a physical sidelink feedback channel associated with said at least one beam having said most suitable signal level and / or quality; as well as The one or more beams of the at least one beam of the plurality of beams for signal transmission are determined based on the absolute difference or the relative difference. 16 . The second terminal device according to claim 11 , wherein the signal level and / or quality is a reference signal received power.

17. A method for communication, comprising: determining, at the first terminal device, availability of at least one beam of a plurality of beams associated with at least one reference signal transmitted by the second terminal device based on the measured signal level and / or quality; performing a beam-by-beam comparison between the at least one beam of the plurality of beams determined to be available, wherein the beam-by-beam comparison is based on the measured signal level and / or quality for identifying at least one beam having a most suitable signal level and / or quality for signal transmission; as well as An indication is sent to the second terminal device indicating at least one of the following: the at least one beam having the most suitable signal level and / or quality; or the at least one beam among the multiple beams is available.

18. A method for communication, comprising: At the second terminal device, sending at least one reference signal associated with at least one beam of the plurality of beams to the first terminal device; monitoring from the first terminal device for an indication indicating at least one of: at least one beam in the plurality of beams having a most suitable signal level and / or quality; or the at least one beam in the plurality of beams being available; as well as Based on the monitoring, one or more beams of the at least one beam of the plurality of beams are determined for signal transmission.

19. An apparatus for communication, comprising: means for determining, at the first terminal device, availability of at least one beam of a plurality of beams associated with at least one reference signal transmitted by the second terminal device based on the measured signal level and / or quality; means for performing a beam-by-beam comparison between said at least one of said plurality of beams determined to be available, wherein said beam-by-beam comparison is based on said measured signal level and / or quality for identifying at least one beam having a most suitable signal level and / or quality for signal transmission; as well as Means for sending an indication to the second terminal device indicating at least one of: the at least one beam having the most suitable signal level and / or quality; or the at least one beam of the plurality of beams is available.

20. An apparatus for communication, comprising: means for transmitting, at the second terminal device, at least one reference signal associated with at least one beam of the plurality of beams to the first terminal device; means for monitoring from said first terminal device for an indication indicating at least one of: at least one beam of said plurality of beams having a most suitable signal level and / or quality; or said at least one beam of said plurality of beams being available; as well as Means for determining, based on the monitoring, one or more beams of the at least one of the plurality of beams for signal transmission.

21. A non-transitory computer readable medium comprising program instructions, which, when executed by a device, cause the device to at least perform the method according to any one of claims 17 to 18.

Images