Method and apparatus for sidelink beam alignment

Abstract

Methods, apparatus, and systems for beam alignment in sidelink communications are disclosed. The apparatus comprises a first UE configured to: receive a first radio signal from a second UE using at least one first antenna; determining a first direction associated with the received first radio signal based on the estimated angle of arrival of the received first radio signal at the first UE; selecting a beam from among a plurality of beams for communication with the second UE based on the determined first direction; and transmitting a second radio signal to the second UE on the selected beam using the at least one second antenna.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 377,539, filed on September 29, 2022, entitled “Sidelink beam alignment in V2X communication,” the entire contents of which are incorporated herein by reference. Technical Field

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

[0003] Sidelink communication technology enables direct communication between two or more devices (e.g., two or more vehicles in Vehicle-to-Everything (V2X) communication). Some sidelink communications (e.g., sidelink communications that require high data rates) preferably use high-frequency radio signals to transmit and receive data. But high-frequency radio signals suffer from high path loss, thus limiting the communication range between devices. Beamforming with narrow beams can provide compensation for path loss. Therefore, beamforming is useful in high-frequency operations in sidelink communications. But beamforming between two vehicles in sidelink communications is often challenging, especially when the two vehicles are moving. Systems and methods for efficient and accurate sidelink beamforming are desired. Summary of the invention

[0004] According to some embodiments of the present disclosure, a first user equipment (UE) is provided. The first UE includes a memory storing instructions and a processor, the processor being configured to execute the instructions stored in the memory to: receive a first radio signal from a second UE using at least one first antenna; determine a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; select a beam from a plurality of beams for communicating with the second UE based on the determined first direction; and transmit a second radio signal to the second UE on the selected beam using at least one second antenna.

[0005] According to some embodiments of the present disclosure, a method for a first UE in sidelink communication is provided. The method includes: receiving a first radio signal from a second UE using at least one first antenna; determining a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; selecting a beam from a plurality of beams for communicating with the second UE based on the determined first direction; and transmitting a second radio signal to the second UE on the selected beam using at least one second antenna.

[0006] According to some embodiments of the present disclosure, a non-transitory computer-readable medium is provided, which stores instructions that can be executed by one or more processors of a first UE in sidelink communication to perform a method. The method includes: receiving a first radio signal from a second UE using at least one first antenna; determining a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; selecting a beam from a plurality of beams for communicating with the second UE based on the determined first direction; and transmitting a second radio transmission to the second UE on the selected beam using at least one second antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] [ Figure 1 ] Figure 1 is a schematic diagram illustrating sidelink beamforming in a communication system consistent with some embodiments of the present disclosure.

[0008] [ Figure 2 ] Figure 2 It is shown that some embodiments of the present disclosure are consistent with the Figure 1 Schematic diagram of sidelink beamforming for estimating the angle of arrival of a sidelink signal in a communication system.

[0009] [ Figure 3 ] Figure 3 is a schematic diagram illustrating angle of arrival estimation using two FR1 omnidirectional antennas disposed on a UE, consistent with some embodiments of the present disclosure.

[0010] [ Figure 4 ] Figure 4 is a schematic diagram illustrating determination of the FR1 angle of arrival relative to the FR2 antenna orientation consistent with some embodiments of the present disclosure.

[0011] [ Figure 5 ] Figure 5 is a schematic diagram illustrating an exemplary test setup including two UEs and a circular antenna array for detecting directional transmissions from one of the UEs, consistent with some embodiments of the present disclosure.

[0012] [ Figure 6 ] Figure 6 is another schematic diagram illustrating an exemplary test setup including two UEs and a circular antenna array for detecting directional transmissions from one of the UEs, consistent with some embodiments of the present disclosure.

[0013] [ Figure 7 ] Figure 7 is a flow chart illustrating a method for beam alignment in sidelink communications consistent with some embodiments of the present disclosure.

[0014] [ Figure 8 ] Figure 8 is a flow chart illustrating a method for detecting directional transmissions consistent with some embodiments of the present disclosure.

[0015] [ Fig. 9 ] Fig. 9 is a block diagram of a UE consistent with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0016] Reference will now be made in detail to exemplary embodiments, examples of which are shown in the accompanying drawings. The following description refers to the accompanying drawings, wherein, unless otherwise specified, the same numbers in different drawings represent the same or similar elements. The embodiments set forth in the following description of the exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of systems, devices, and methods consistent with aspects related to the present disclosure as recorded in the appended claims.

[0017] Figure 1 is a schematic diagram illustrating sidelink beamforming in a communication system consistent with some embodiments of the present disclosure. Figure 1 , the communication system 100 includes a first UE (UE-A) and a second UE (UE-B) that communicate with each other via sidelink communication. For example, the sidelink communication may be vehicle-to-everything (V2X) communication, and both UE-A and UE-B are vehicles. For example, UE-B may be a transmitter (Transmitter, Tx) UE that is configured or programmed to transmit signals or data to UE-A and / or other nodes (not shown) in the communication system 100. The other nodes may be network nodes (e.g., base stations), roadside units, relay nodes, or other UEs in the communication system 100. UE-A may be a receiver (Receiver, Rx) UE that is configured or programmed to receive signals or data transmitted from UE-B and / or other nodes in the communication system 100.

[0018] Reference Figure 1, the sidelink communication between UE-A and UE-B can be a beam-based communication. In this case, sidelink beamforming is used so that the beam from UE-B (the oval 102 filled with black) and the beam from UE-A (the oval 104 filled with black) can be aligned. The terms "beam alignment" and "beamforming" are used interchangeably in the present disclosure. The alignment of the beams at UE-B and UE-A can increase the communication range on the sidelink, the achievable data rate, and the overall system spectral efficiency.

[0019] Reference Figure 1 , both UE-A and UE-B may be located at a low altitude, and both UE-A and UE-B may be moving. In addition, in the sidelink, each UE communicates with one or more UEs. These features are different from the uplink / downlink formed by the UE and the base station (e.g., gNB), where one end of the link (the base station) generally does not move and is located at a higher altitude than the other end of the link (the UE). In addition, in the uplink / downlink communication, each UE communicates only with the base station. Due to the differences, the sequential beam alignment process used in the beamforming between the base station and the UE may not be applicable to the sidelink beamforming between UE-A and UE-B. In addition, even if the process used in the beamforming between the base station and the UE can be applied to the sidelink beamforming, because the process performs an exhaustive search for the best beam pair, it may be slow and may cause significant overhead for the sidelink beamforming. At least some embodiments of the present disclosure solve the above-mentioned problems in the sidelink beamforming.

[0020] Figure 2 It is shown that some embodiments of the present disclosure are consistent with the Figure 1 Schematic diagram of sidelink beamforming for estimating the angle of arrival of a sidelink signal in a communication system. Figure 2, UE-A and UE-B may periodically broadcast sidelink signals, such as Cooperative Awareness Message (CAM) or Basic Safety Message (BSM). The CAM or BSM may include information related to the transmitting UE (UE-A or UE-B), such as the current position, speed, and heading of the transmitting UE. Such broadcast messages may be transmitted using omnidirectional antennas in the Intelligent Transportation System (ITS) bands (e.g., 5.9 GHz for USA, EU, China, etc., and 760 MHz for Japan). These bands correspond to frequency range 1 (FR1) in the 3rd Generation Partnership Project (3GPP) standard. The frequency range of FR1 is from 410 MHz to 7125 MHz. UE-A or UE-B may be equipped with one or more omnidirectional antennas for receiving FR1 signals (e.g., CAM), and may be able to estimate one or more angles of arrival (Angle-Of-Arrival, AoA) of the received FR1 signals. As used in this disclosure, the term "AoA" includes (one or more) directions of arrival (Direction-Of-Arrival, DoA), and the terms AoA and DoA are used interchangeably in this disclosure. Figure 2 As shown, UE-B transmits CAM omnidirectionally, and UE-A determines the arrival angle of the incoming CAM transmitted from UE-B. Similarly, UE-A transmits a CAM omnidirectionally, and UE-B determines the angle of arrival of the incoming CAM transmitted from UE-A. The method for determining the angle of arrival is well known in the art. For the sake of brevity, the description of the method for determining the angle of arrival is omitted here.

[0021] In some embodiments, the content of the received CAM (e.g., the location of UE-A or the location of UE-B) can be used to resolve any ambiguity in estimating the angle of arrival (e.g., front / back or right / left ambiguity). For example, a CAM broadcast from UE-A and received by UE-B may include the location information of UE-A, so that UE-B can use the received CAM to determine the angle of arrival of the incoming CAM. This location information is used when

[0022] In some embodiments, the estimated angle of arrival is used to select a beam for directional transmission or reception of a higher frequency beam (e.g., a FR2 beam). The frequency range of FR2 can be two frequency sub-ranges: FR2-1 from 24250 MHz to 52600 MHz and FR2-2 from 52600 MHz to 71000 MHz. For example, UE-B can use the estimated angle of arrival of the incoming CAM To select a beam for directionally transmitting a signal to UE-A using a directional antenna (e.g., a phased array).

[0023] At least some embodiments of the disclosed method allow for fast and accurate sidelink beam alignment without exhaustive searching among all possible beam pairs, which would be slower and incur higher overhead. In addition, compared to schemes that rely solely on location information (e.g., area or coordinates) for sidelink beam alignment, at least some embodiments of the disclosed method utilize estimated angles of arrival, thereby improving accuracy and enabling beam alignment even in non-line-of-sight (NLOS) scenarios.

[0024] In some embodiments, UE-A and / or UE-B may be equipped with multiple FR1 omni-directional antennas or multiple antenna panels, so that the arrival angle estimation of the FR1 signal can be performed using multiple FR1 omni-directional antennas or antenna panels, as shown below in combination with Figure 3 discussed.

[0025] Although the exemplary embodiments in the present disclosure relate to FR1 and FR2 communications, the application of the disclosed methods is not limited thereto. The methods described in the present disclosure can be applied to any frequency band, including frequency bands used in current sidelink communications, as well as frequency bands used in future generation (6th generation (6G), 7th generation (7G), or any future generation) sidelink communications. The methods described in the present disclosure can also be applied to other systems, such as downlink / uplink or wireless local area networks, or any other system that complies with other standards (e.g., IEEE standards).

[0026] Figure 3 is a schematic diagram illustrating angle of arrival estimation using two FR1 omnidirectional antennas disposed on a UE consistent with some embodiments of the present disclosure. Figure 3 , the communication system 300 includes a first UE (UE-A), a second UE (UE-B), and a third UE (UE-C) communicating with each other via sidelink communication. For example, the sidelink communication may be V2X communication, and UE-A, UE-B, and UE-C are vehicles. Figure 3A top view of the vehicle is shown. UE-A can use two FR1 omnidirectional antennas (A1, A2) to receive FR1 signals (e.g., CAM) transmitted from UE-B and UE-C. Each of the two FR1 omnidirectional antennas is set close to the corresponding side of the vehicle. In some embodiments, the configuration of the two FR1 omnidirectional antennas (A1, A2) can be in the form of a 2-element linear antenna array. Typically, due to different path lengths and corresponding propagation delays (τ1, τ2), the phase of the FR1 signal received at antenna A1 is different from the phase of the FR1 signal received at antenna A2. In some embodiments, by comparing the phase of the FR1 signal received at each antenna, UE-A can estimate the azimuth in the (x, y) plane corresponding to the direction in which the source (UE-B or UE-C) of the transmitted FR1 signal is located.

[0027] There can be multiple angles from which the transmitted FR1 signal can arrive at different antennas with the same phase difference. Figure 3 As shown, due to the radial symmetry around the A1-A2 axis, the signal (310) transmitted from UE-B can be received at the antenna A1 of UE-A with the same phase difference as the signal (320) transmitted from UE-C. Therefore, UE-A may not be able to distinguish between the signal (320) incoming from the left side of the A1-A2 axis and the signal (310) incoming from the right side of the A1-A2 axis. This may cause left / right or longitudinal ambiguity. If A1 and A2 are placed along the longitudinal axis of UE-A, there will be similar ambiguity in the lateral direction. At least some embodiments of the present disclosure resolve this ambiguity by using location information contained in the received FR1 signal. For example, the CAM received from UE-B may include information about the geographic coordinates (latitude, longitude, altitude) of the current location of UE-B. For another example, the sidelink control information (SCI) received from UE-B may include information about the regional identification (ID) corresponding to the current location of UE-B. By combining the angle of arrival estimate with the location information received from UE-B and / or UE-C, UE-A may achieve improved angular accuracy when estimating the angle of arrival.

[0028] In some embodiments, UE-A may use more than two FR1 omnidirectional antennas to receive FR1 (e.g., CAM) signals. The number of FR1 omnidirectional antennas may be any number. For example, UE-A may use four omnidirectional antennas to receive FR1 signals transmitted from UE-B. Four omnidirectional antennas may be disposed on the top of UE-A, each omnidirectional antenna at a corner on the top of UE-A. The four top corner antennas may form a 2×2 planar array of antennas. At least some embodiments of the present disclosure resolve the above-mentioned ambiguity (e.g., longitudinal ambiguity) by using more than two FR1 antennas without using the location information of UE-B or UE-C.

[0029] In some embodiments, UE-A may perform FR2 beam selection based on an estimated angle of arrival of a FR1 signal. Once UE-A has an estimate of the direction or angle (at least the azimuth) of arrival of a FR1 signal transmitted by a signal source (e.g., UE-B or UE-C), UE-A may use the estimate to select a Tx or Rx beam pointing in the corresponding direction to communicate directionally with the signal source (e.g., UE-B or UE-C) in FR2 using a directional antenna (e.g., a phased array or antenna panel). In some embodiments, UE-A may select a Tx or Rx beam based on an implicit mapping between a direction (or angle) and a beam. The rules for such mapping may be predefined, preconfigured at UE-A, or configured by a network node. In some embodiments, prior to beam selection, UE-A may analyze the estimated angle of arrival (or direction of arrival) to determine the direction relative to a coordinate system of the directional antenna (e.g., relative to a FR2 phased array). In some embodiments, the determination is obtained via preconfiguration during device manufacturing or via calibration.

[0030] Figure 4 is a schematic diagram illustrating determination of the FR1 angle of arrival relative to the FR2 antenna orientation consistent with some embodiments of the present disclosure. Figure 4 , the communication system 400 includes a first UE (UE-A) and a second UE (UE-B) that communicate with each other via sidelink communication. For example, the sidelink communication may be V2X communication, and UE-A and UE-B are vehicles. UE-A may receive a FR1 signal (e.g., CAM) transmitted from UE-B using four FR1 omnidirectional antennas (A1 to A4). The four FR1 omnidirectional antennas A1 to A4 are disposed on the top of UE-A, each omnidirectional antenna being at a corner on the top. In some embodiments, the four top corner antennas A1 to A4 are considered to be a 2×2 planar array of antennas.

[0031] refer to Figure 4 , UE-A can use the 2×2 top array to estimate the arrival angle of the FR1 signal transmitted from UE-B Angle of arrival is given relative to the direction pointing forward of the vehicle (the x-axis). Figure 4 As shown, UE-A further includes a directional FR2 antenna 410 located in the front bumper and a directional FR2 antenna 420 located on the side. If the FR2 antenna 410 is used for directional communication, the beam is relative to the FR2 phased array (x ^ )'s normal vector should point to the angle and is roughly the same, especially when UE-B is located far away from UE-A. However, if the FR2 antenna 420 is used for directional communication, the beam is relatively stable relative to the FR2 phased array (y ^ )'s normal vector should point to the angle Approximately Especially when UE-B is located far away from UE-A. At least some embodiments of the present disclosure address the impact of different locations of FR2 antennas by performing an analysis of the direction (or angle) determined by the angle of arrival estimation.

[0032] For example, in some embodiments, UE-A may use a 2×2 top array in FR1 to perform an analysis of the angle of arrival observed in FR1 to determine a direction relative to a coordinate system of directional antenna 410 or 420. For example, UE-A may use a 2×2 top array to analyze direction 440 observed in FR1 to account for clockwise or counterclockwise changes at FR2 antenna 410 or 420 to obtain direction 450 or 430 relative to FR2 antenna 410 or 420. In this way, the effects of different placements of FR1 and FR2 antennas and distance differences between vehicles are eliminated, resulting in improved beamforming accuracy.

[0033] about Figure 4 The described exemplary embodiment includes four FR1 antennas disposed on the top of UE-A. However, the method of the present disclosure is not limited thereto. The number of FR1 antennas may be any number, and the antennas may be disposed anywhere on the vehicle, for example, on the side of the vehicle. In addition, the FR2 antennas may be disposed anywhere on the vehicle, for example, on the rear bumper or on the top of the vehicle.

[0034] Figure 5 is a schematic diagram showing a first test setup for detecting directional transmissions from a device; and Figure 6 is a schematic diagram illustrating a second test setup for detecting directional transmissions from a device, consistent with some embodiments of the present disclosure. Figure 5 and Figure 6Each of the first test setup and the second test setup consists of UE-A (e.g., a cellular phone), UE-B (e.g., a vehicle), and a circular antenna array (e.g., a plurality of antennas disposed on the inner wall of a ring) to detect directional transmissions from the vehicle. Figure 5 compared to, Figure 6 The second test setup in also includes a blocking surface 610 that blocks the line-of-sight signal between UE-A and UE-B, and a highly reflective surface 620 that ensures that UE-B can receive a strong non-line-of-sight component from UE-A's FR1 signal transmission.

[0035] exist Figure 5 and Figure 6 In the embodiment of the present invention, UE-A and UE-B can operate in FR1 and FR2. UE-B is the UE under test, and UE-A is a controllable UE or a software defined radio platform. UE-B is deployed in a ring having an antenna array arranged on the inner wall of the ring. The antenna array is mounted on the inner wall of the ring so that the Rx beam and / or Tx beam of UE-B is substantially perpendicular to the corresponding surface of each antenna.

[0036] refer to Figure 5 In the first test setup, UE-A transmits a FR1 signal (e.g., CAM) and UE-B receives the FR1 signal. If UE-B performs narrow beam transmission in FR2 in the direction of UE-A without any FR2 beam alignment occurring, this means that UE-B is able to obtain beam alignment information from the CAM received from UE-A.

[0037] refer to Figure 6 In a second test setup, UE-A transmits a FR1 signal (e.g., a CAM), and UE-B receives the FR1 signal. The CAM transmitted from UE-A is received from a non-line-of-sight (NLoS) direction at UE-B. The CAM transmitted from UE-A may include location information of UE-A. If UE-B performs narrow beam transmission in FR2 in the direction of arrival of the CAM transmitted from UE-A (NLoS component) instead of line-of-sight (LoS), this provides an indication that UE-B practices the method disclosed in the present disclosure.

[0038] Figure 7 700 (eg, for beam alignment) in sidelink communications consistent with some embodiments of the present disclosure. The method 700 may be performed by a UE in sidelink communications. For example, the method 700 may be performed by Figures 1 to 4 Executed by UE-A or UE-B.

[0039] refer to Figure 7, the method 700 includes: step 702, using at least one first antenna to receive a first radio signal from a second UE. For example, the first UE (such as Figures 1 to 4 UE-A) can be obtained from a second UE (such as Figures 1 to 4 In one embodiment, the first radio signal may be a FR1 signal (e.g., CAM or BSM). In some embodiments, the at least one first antenna may be one or more FR1 omnidirectional antennas. For example, the at least one first antenna may be Figure 3 The dual antenna linear array shown in or Figure 4 The four-antenna planar array shown in . The number of FR1 omnidirectional antennas can be any number, and the shape of the array formed by the FR1 omnidirectional antennas can be any shape (linear, rectangular, square, circular, etc.). In some embodiments, at least one first antenna can also be a single FR1 omnidirectional antenna including multiple antenna panels. In some embodiments, the first radio signal can include location information providing the current location of the second UE. The location information can be the geographic coordinates (latitude, longitude, altitude) of the current location of the second UE, or an area ID corresponding to the current location of the second UE.

[0040] The method 700 includes: step 704, based on the estimated arrival angle of the received first radio signal at the first UE, determining a first direction associated with the received first radio signal. Figure 4 UE-A) determines the direction of an incoming first radio signal (e.g., CAM) based on an estimate of the angle of arrival of the first radio signal at the first UE. The estimated angle of arrival of the received first radio signal at the first UE may include at least one of the following: the angle between the x-axis and the direction of the incoming first radio signal, or the angle between the y-axis and the direction of the incoming first radio signal. In some embodiments, the estimated angle of arrival of the received first radio signal at the first UE may also include the angle between the z-axis and the direction of the incoming first radio signal. In some embodiments, the first UE may select any other reference axis instead of the x, y, z axes. In some embodiments, at least one first antenna may include two or more omnidirectional antennas, and the angle of arrival of the received first radio signal may be estimated based on a comparison of the phases of the first radio signals received at the two or more omnidirectional antennas. In some embodiments, the received first radio signal may include the location information of the second UE, and the first UE considers the location information of the second UE when determining the angle of arrival of the first radio signal.

[0041] Method 700 includes: step 706, selecting a beam from a plurality of beams for communicating with a second UE based on the determined first direction. In some embodiments, the first UE selects a beam from a plurality of beams based on a corresponding mapping between the plurality of beams and a plurality of directions of a plurality of signals incoming to the first UE. The corresponding mapping rule may be predefined, preconfigured at the first UE, or configured by a network node. In some embodiments, before selecting a beam from a plurality of beams, the first UE may determine a direction of a beam from at least one second antenna relative to a coordinate system of at least one second antenna based on the determined first direction associated with the received first radio signal. For example, the first UE may perform an analysis of a direction determined based on an angle of arrival estimate of the first radio signal to obtain a direction relative to a coordinate system of the second antenna, as described above with respect to Figure 4 The direction of the beam may be determined based on one or more parameters, such as a location of the second antenna at the first UE, a distance between the first UE and the second UE, etc.

[0042] The method 700 includes: step 708, using at least one second antenna to transmit a second radio signal to the second UE on the selected beam. The at least one second antenna can be at least one directional antenna that communicates with the second UE using the FR2 beam. In this way, directional communication based on the FR2 beam between the first UE and the second UE can be easily established using (one or more) aligned beams.

[0043] Figure 8 8 is a flow chart illustrating a method 800 for detecting directional transmissions consistent with some embodiments of the present disclosure. The method 800 may be performed by two UEs in sidelink communication. For example, the method 800 may be performed by Figure 5 or Figure 6 Executed by UE-A and UE-B shown in FIG.

[0044] refer to Figure 8 The method 800 includes: step 802, deploying a first UE in a ring having a plurality of antennas arranged along the perimeter (inner wall) of the ring. The first UE is tested to determine whether the UE practices Figure 7 The first UE may be capable of operating in an FR2 beam. The first UE may be a vehicle in V2X communication, for example, Figure 5 and Figure 6 The vehicle shown in .

[0045] Method 800 includes: step 804, sending a first radio signal from the second UE to the first UE. The first radio signal may be a FR1 signal (e.g., CAM) transmitted from the second UE. The second UE may be capable of operating in an FR2 beam. The second UE may be Figure 5 and Figure 6 The cellular telephone shown in .

[0046] The method 800 includes: step 806, receiving a response signal transmitted in response to the first radio signal from the first UE. Figure 7 In an example of a method, upon receiving a first radio signal (e.g., a CAM), the first UE determines the angle of arrival of the first radio signal. The first UE may also analyze an estimated direction associated with the estimated angle of arrival to determine a direction relative to a coordinate system of a second antenna. The first UE may then select a beam and transmit a response signal on the selected beam using the second antenna.

[0047] Method 800 includes: step 808, determining whether the direction associated with the response signal transmitted from the first UE matches the direction of the first radio signal. If the direction associated with the response signal determined by one or more antennas on the inner wall of the ring matches the direction of the first radio signal, it can be concluded that the first UE is actually Figure 7 Conclusions of the method.

[0048] Fig. 9 900 is a block diagram of a UE 900 consistent with some embodiments of the present disclosure. UE 900 may be a UE in sidelink communication, such as Figures 1 to 6 UE-A or UE-B. UE 900 may be installed in a mobile vehicle or in a fixed location. UE 900 may take any form, including but not limited to a vehicle, a component installed in a vehicle, a laptop computer, a wireless terminal including a mobile phone, a wireless handheld device or a wireless personal device, or any other form. Fig. 9 UE 900 may include an antenna 902, which may be used to transmit or receive electromagnetic signals to / from other nodes (such as network nodes (e.g., base stations), road side units (RSUs), relay nodes, base stations, or other UEs). Antenna 902 may be one or more FR1 omnidirectional antennas, such as Figure 3 Antennas A1 and A2, or Figure 4 Antenna 902 may also be one or more FR2 antennas, such as Figure 4Antenna 902 may include one or more antenna elements and may implement different input-output antenna configurations, such as a multiple input multiple output (MIMO) configuration, a multiple input single output (MISO) configuration, and a single input multiple output (SIMO) configuration. In some embodiments, antenna 902 may include multiple (e.g., tens or hundreds) of antenna elements and may implement multi-antenna functions such as beamforming. In some embodiments, antenna 902 is a single antenna.

[0049] UE 900 may include a transceiver 904 coupled to antenna 902. Transceiver 904 may be a wireless transceiver at UE 900 and may perform bidirectional communication with a base station or other UEs. For example, transceiver 904 may receive wireless signals from / transmit wireless signals to a base station via downlink / uplink communication. Transceiver 904 may also receive / transmit wireless signals from / to another UE or RSU via sidelink communication. Transceiver 904 may include a modem to modulate packets and provide the modulated packets to antenna 902 for transmission, and demodulate packets received from antenna 902.

[0050] UE 900 may include memory 906. Memory 906 may be any type of computer-readable storage medium, including volatile or non-volatile memory devices or combinations thereof. Computer-readable storage media include, but are not limited to, non-transitory computer storage media. Non-transitory storage media may be accessed by general-purpose or special-purpose computers. Examples of non-transitory storage media include, but are not limited to, portable computer disks, hard disks, random access memory (Random Access Memory, RAM), read-only memory (Read-Only Memory, ROM), erasable programmable read-only memory (ErasableProgrammable Read-Only Memory, EPROM), electrically erasable programmable ROM (Electrically ErasableProgrammable ROM, EEPROM), digital versatile disks (Digital Versatile Disk, DVD), flash memory, compact disk (Compact Disk, CD) ROM or other optical disk storage, disk storage or other magnetic storage devices, etc. Non-transitory media may be used to carry or store desired program code devices (e.g., instructions and / or data structures), and may be accessed by general-purpose or special-purpose computers, or general-purpose or special-purpose processors. In some examples, software / program code can be transmitted from a remote source (e.g., a website, server, etc.) using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave. In such examples, coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are within the scope of the medium definition. Combinations of the above examples are also within the scope of computer-readable media.

[0051] The memory 906 may store information related to the identification of the UE 900 and the signals and / or data received by the antenna 902. The memory 906 may also store post-processed signals and / or data. The memory 906 may also store computer-readable program instructions, mathematical models, and algorithms used in the signal processing in the transceiver 904 and the calculation in the processor 908. For example, the memory 906 may store computer-readable program instructions, mathematical models, and algorithms for estimating the angle of arrival of FR1 signals (e.g., CAM). The memory 906 may also store computer-readable program instructions for being executed by the processor 908 to operate the UE 900 to perform various functions described in the present disclosure. In some examples, the memory 906 may include a basic input / output system (Basic Input / Output System, BIOS), which may control basic hardware or software operations, such as interaction with peripheral components or devices. In some embodiments, the memory 906 includes both LTE and NR modules. In some other embodiments, the memory 906 includes only the NR module. In some other embodiments, the memory 906 includes only the LTE module.

[0052] The computer-readable program instructions of the present disclosure may be assembly instructions, instruction set architecture (Instruction-Set-Architecture, ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages ​​(including object-oriented programming languages ​​and conventional process programming languages). The computer-readable program instructions may be executed completely on a computing device as an independent software package, or may be executed partially on a first computing device and partially on a second computing device away from the first computing device. In the latter case, the second remote computing device may be connected to the first computing device via any type of network, including a local area network (LAN) or a wide area network (WAN).

[0053] UE 900 may include a processor 908, which may include a hardware device with processing capabilities. Processor 908 may include at least one of the following: a general-purpose processor, a digital signal processor (Digital Signal Processor, DSP), a central processing unit (Central Processing Unit, CPU), a microcontroller, an application-specific integrated circuit (Application Specific Integrated Circuit, ASIC), a field programmable gate array (Field Programmable Gate Array, FPGA), a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component or other programmable logic device. Examples of general-purpose processors include, but are not limited to, microprocessors, any conventional processors, controllers, microcontrollers, or state machines. In some embodiments, processor 908 may be implemented using a combination of devices (e.g., a combination of DSP and microprocessors, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration). Processor 908 may receive downlink signals or sidelink signals from transceiver 904 and further process these signals. Processor 908 may also receive data packets from transceiver 904 and further process these packets. In some embodiments, processor 908 may be configured to operate a memory using a memory controller. In some embodiments, the memory controller may be integrated into the processor 908. The processor 908 may be configured to execute computer-readable instructions stored in a memory (eg, the memory 906) to enable the UE 900 to perform various functions.

[0054] UE 900 may include a global positioning system (GPS) 910. GPS 910 may be used to implement location-based services or other services based on the geographic location of UE 900 and / or synchronization among UEs. GPS 910 may receive a global navigation satellite system (GNSS) signal from a single satellite or multiple satellite signals via antenna 902 and provide the geographic location of UE 900 (e.g., coordinates of UE 900). In some embodiments, GPS 910 may be omitted.

[0055] UE 900 may include an input / output (I / O) device 912, which may be used to transmit the results of signal processing and calculation to a user or another device. I / O device 912 may include a user interface, which includes a display and an input device for transmitting user commands to processor 908. The display may be configured to display the state of signal reception at UE 900, data stored at memory 906, the state of signal processing and calculation results, etc. The display may include but is not limited to a cathode ray tube (Cathode Ray Tube, CRT), a liquid crystal display (Liquid Crystal Display, LCD), a light-emitting diode (Light-Emitting Diode, LED), a gas plasma display, a touch screen or other image projection devices for displaying information to a user. The input device may be any type of computer hardware device for receiving data and control signals from a user. The input device may include but is not limited to a keyboard, a mouse, a scanner, a digital camera, a joystick, a trackball, a cursor direction key, a touch screen monitor or an audio / video commander, etc.

[0056] The UE 900 may also include a machine interface 914 , such as an electrical bus that connects the transceiver 904 , memory 906 , processor 908 , GPS 910 , and I / O devices 912 .

[0057] In some embodiments, UE 900 may be configured or programmed for sidelink communication. For example, UE 900 may be a first UE in sidelink communication, and processor 908 may be configured to execute instructions stored in memory 906 to: receive a first radio signal from a second UE using at least one first antenna; determine a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; select a beam from a plurality of beams for communication with the second UE based on the determined first direction; and transmit a second radio signal to the second UE on the selected beam using at least one second antenna.

[0058] As used in the present disclosure, the use of the term "or" in a list of items indicates an inclusive list. A list of items may be prefixed with phrases such as "at least one" or "one or more". For example, a list of at least one of A, B, or C includes A or B or C or AB (i.e., A and B) or AC or BC or ABC (i.e., A and B and C). In addition, as used in the present disclosure, prefixing a list of conditions with the phrase "based on" should not be interpreted as a set of conditions "based only on", but rather should be interpreted as a set of conditions "based at least in part on". For example, a result described as "based on condition A" may be based on both condition A and condition B without departing from the scope of the present disclosure.

[0059] In this specification, the terms "include", "contain" or "comprise" can be used interchangeably and have the same meaning, and are interpreted as inclusive and open-ended. The terms "include", "contain" or "comprises" can be used before a list of elements and indicate that at least all of the listed elements in the list are present, but other elements that are not in the list may also be present. For example, if A includes B and C, then {B, C} and {B, C, D} are both within the scope of A.

[0060] In conjunction with the accompanying drawings, the present disclosure describes example configurations that do not represent all examples that can be implemented or all configurations within the scope of the present disclosure. The term "exemplary" should not be interpreted as "preferred" or "advantageous compared to other examples", but should be interpreted as "illustration, instance, or example". By reading this disclosure, including the description of the embodiments and the accompanying drawings, a person of ordinary skill in the art will understand that alternative embodiments can be used to implement the technology disclosed herein. Those skilled in the art will understand that the embodiments described herein or certain features of the embodiments can be combined to obtain other embodiments for practicing the technology described in the present disclosure. Therefore, the present disclosure is not limited to the examples and designs described herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein.

[0061] The flowchart and block diagram in the figure show examples of the architecture, functions and operations of possible implementations of the systems, methods and devices according to various embodiments. It should be noted that in some alternative implementations, the functions marked in the box may occur outside the order marked in the figure. For example, depending on the functions involved, the two boxes shown in succession can actually be executed substantially simultaneously, or the boxes can sometimes be executed in reverse order. Similarly, in the method consistent with various embodiments, additional steps may be included in such a method, and some steps may be omitted or combined.

[0062] It should be understood that the described embodiments are not mutually exclusive, and elements, components, materials or steps described in conjunction with one exemplary embodiment may be combined with or eliminated from other embodiments in a suitable manner to achieve the desired design purpose.

[0063] References herein to "some embodiments" or "some exemplary embodiments" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment. The appearance of the phrases "one embodiment," "some embodiments," or "another embodiment" throughout this disclosure does not necessarily refer to the same embodiment, nor are they necessarily separate or alternative embodiments that are mutually exclusive with other embodiments.

[0064] In addition, the articles "a" and "an" as used in this disclosure and the appended claims should generally be construed to mean "one or more" unless specified otherwise or clearly directed to a singular form by context.

[0065] Unless expressly stated otherwise, each numerical value and range should be interpreted as being approximate, as would the word "about" or "approximately" preceding the value of the numerical value or range.

[0066] Although elements in the following method claims, if any, are recited in a specific order, these elements are not necessarily intended to be limited to being implemented in that specific order unless the claim recitation otherwise implies a specific order for implementing some or all of these elements.

[0067] It should be understood that certain features of the present disclosure described in the context of separate embodiments for the sake of clarity may also be provided in combination in a single embodiment. Conversely, various features of the present specification described in the context of a single embodiment for the sake of brevity may also be provided separately, or in any suitable sub-combination, or as appropriate in any other described embodiment of the present specification. Certain features described in the context of various embodiments are not essential features of these embodiments unless otherwise stated.

[0068] It should also be understood that those skilled in the art may make various modifications, substitutions and changes to the details, materials and arrangements of the components described and illustrated for the purpose of explaining the nature of the described embodiments without departing from the scope. Accordingly, the appended claims cover all such substitutions, modifications and changes falling within the aspects of the claims.

[0069] Clause 1. A first user equipment (UE) for communication, the first UE comprising: a memory storing instructions; and A processor configured to execute instructions stored in the memory to: receiving a first radio signal from a second UE using at least one first antenna; determining a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; selecting a beam from among a plurality of beams for communicating with a second UE based on the determined first direction; and A second radio signal is transmitted to a second UE on the selected beam using the at least one second antenna.

[0070] Clause 2. The first UE of clause 1, wherein the at least one first antenna is a plurality of omni-directional antennas and the at least one second antenna is at least one directional antenna.

[0071] Clause 3. The first UE of clause 1, wherein the communication is a directional communication between the first UE and the second UE.

[0072] Clause 4. The first UE of clause 1, wherein the processor is further configured to execute instructions stored in the memory to: Prior to selecting a beam from among the plurality of beams, a direction of the beam from the at least one second antenna relative to a coordinate system of the at least one second antenna is determined based on at least a first direction associated with the received first radio signal.

[0073] Clause 5. The first UE of clause 1, wherein the received first radio signal comprises location information providing a location of the second UE.

[0074] Clause 6. The first UE of clause 5, wherein, upon determining the first direction associated with the received first radio transmission, the processor is further configured to execute instructions stored in the memory to: A first direction is determined based on at least one radio measurement of the received first radio signal and the position information.

[0075] Clause 7. The first UE of clause 5, wherein the location information comprises at least one of: geographic coordinates of the second UE, or an area ID corresponding to a current location of the second UE.

[0076] Clause 8. The first UE of clause 1, wherein the first radio signal is a cooperative awareness message (CAM) or a basic safety message (BSM).

[0077] Clause 9. The first UE of clause 1, wherein the first radio signal is transmitted using FR1.

[0078] Clause 10. The first UE of clause 1, wherein the at least one second antenna is configured to communicate with the second UE using FR2.

[0079] Clause 11. A first UE according to clause 1, wherein the at least one first antenna comprises a plurality of first antennas, and an angle of arrival of the received first radio signal is estimated based on a comparison of phases of the first radio signal received at two or more of the plurality of first antennas.

[0080] Clause 12. A first UE according to clause 1, wherein the angle of arrival of the received first radio signal at the first UE comprises at least one of: an angle between an x-axis and a direction of the incoming first radio signal, or an angle between a y-axis and a direction of the incoming first radio signal.

[0081] Clause 13. The first UE of clause 12, wherein the angle of arrival further comprises an altitude angle at the first UE.

[0082] Clause 14. The first UE of clause 1, wherein the beam is selected from among the plurality of beams based on a corresponding mapping between the plurality of beams and a plurality of directions of a plurality of signals incoming to the first UE.

[0083] Clause 15. The first UE of Clause 1, wherein the first UE is a vehicle and the at least one second antenna is a linear array of antennas disposed along a longitudinal axis or a lateral axis of the vehicle.

[0084] Clause 16. The first UE of Clause 1, wherein the first UE is a vehicle and the at least one first antenna is disposed on a roof of the vehicle.

[0085] Clause 17. A method for a first user equipment (UE) in sidelink communication, the method comprising: receiving a first radio signal from a second UE using at least one first antenna; determining a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; selecting a beam from among a plurality of beams for communicating with a second UE based on the determined first direction; and A second radio signal is transmitted to a second UE on the selected beam using the at least one second antenna.

[0086] Clause 18. The method of clause 17, wherein the at least one first antenna is a plurality of omnidirectional antennas and the at least one second antenna is at least one directional antenna.

[0087] Clause 19. The method of clause 17, wherein the communication is a directional communication between the first UE and the second UE.

[0088] Clause 20. The method according to Clause 17, further comprising: Prior to selecting a beam from among the plurality of beams, a direction of the beam from the at least one second antenna relative to a coordinate system of the at least one second antenna is determined based on at least the determined first direction associated with the received first radio signal.

[0089] Clause 21. The method of clause 17, wherein the received first radio signal comprises location information providing a location of the second UE.

[0090] Clause 22. The method of clause 21, wherein determining a first direction associated with the received first radio signal further comprises: A first direction is determined based on at least one radio measurement of the received first radio signal and the position information.

[0091] Clause 23. The method of clause 21, wherein the location information comprises at least one of: geographic coordinates of the second UE, or an area ID corresponding to a current location of the second UE.

[0092] Clause 24. The method of clause 17, wherein the first radio signal is a cooperative awareness message (CAM) or a basic safety message (BSM).

[0093] Clause 25. The method of clause 17, wherein the first radio signal is transmitted using FR1.

[0094] Clause 26. The method of clause 17, wherein the at least one second antenna is configured to communicate with the second UE using FR2.

[0095] Clause 27. The method of clause 17, wherein the at least one first antenna comprises a plurality of first antennas, and the angle of arrival of the received first radio signal is estimated based on a comparison of phases of the first radio signal received at two or more of the plurality of first antennas.

[0096] Clause 28. A method according to clause 17, wherein the angle of arrival of the received first radio signal at the first UE comprises at least one of: an angle between an x-axis and the incoming first radio signal direction, or an angle between a y-axis and the incoming first radio signal direction.

[0097] Clause 29. The method of clause 28, wherein the angle of arrival of the received first radio signal at the first UE further comprises an angle of altitude at the first UE.

[0098] Clause 30. The method of clause 17, wherein the beam is selected from among the plurality of beams based on a corresponding mapping between the plurality of beams and a plurality of directions of a plurality of signals incoming to the first UE.

[0099] Clause 31. The method of clause 17, wherein the first UE is a vehicle and the at least one second antenna is a linear array of antennas disposed along a longitudinal axis or a lateral axis of the vehicle.

[0100] Clause 32. The method of clause 17, wherein the first UE is a vehicle, and the at least one first antenna is disposed on a roof of the vehicle.

[0101] Clause 33. A non-transitory computer-readable medium storing instructions executable by one or more processors of a first user equipment (UE) for communication to perform a method comprising: receiving a first radio signal from a second UE using at least one first antenna; determining a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; selecting a beam from among a plurality of beams for communicating with a second UE based on the determined first direction; and A second radio transmission is transmitted to a second UE on the selected beam using the at least one second antenna.

Claims

1. A first user equipment (UE) for communication, the first UE comprising: a memory storing instructions; as well as a processor configured to execute the instructions stored in the memory to: receiving a first radio signal from a second UE using at least one first antenna; determining a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; Based on the determined first direction, select a beam from a plurality of beams for communicating with the second UE; as well as A second radio signal is transmitted to the second UE on the selected beam using at least one second antenna.

2. The first UE according to claim 1, wherein: The at least one first antenna is a plurality of omnidirectional antennas, and the at least one second antenna is at least one directional antenna.

3. The first UE according to claim 1, wherein: The communication is a directional communication between the first UE and the second UE.

4. The first UE according to claim 1, wherein: The processor is further configured to execute the instructions stored in the memory to: Prior to selecting the beam from among the plurality of beams, a direction of the beam from the at least one second antenna relative to a coordinate system of the at least one second antenna is determined based on at least the first direction associated with the received first radio signal.

5. The first UE according to claim 1, wherein: The first received radio signal comprises location information providing the location of the second UE.

6. The first UE according to claim 1, wherein: The first radio signal is a Collaboration Awareness Message (CAM) or a Basic Safety Message (BSM).

7. The first UE according to claim 1, wherein: The first radio signal is transmitted using FR1.

8. The first UE according to claim 1, wherein: The at least one second antenna is configured to communicate with the second UE using FR2.

9. The first UE according to claim 1, wherein: The at least one first antenna includes a plurality of first antennas, and the angle of arrival of the received first radio signal is estimated based on a comparison of phases of the first radio signal received at two or more antennas among the plurality of first antennas.

10. The first UE according to claim 1, wherein: The received angle of arrival of the first radio signal at the first UE comprises at least one of: an angle between an x-axis and an incoming first radio signal direction, or an angle between a y-axis and the incoming first radio signal direction.

11. The first UE according to claim 1, wherein: The beam is selected from among the plurality of beams based on a corresponding mapping between the plurality of beams and a plurality of directions of a plurality of signals incoming to the first UE.

12. The first UE according to claim 1, wherein: The first UE is a vehicle, and the at least one second antenna is a linear array of antennas arranged along a longitudinal axis or a lateral axis of the vehicle.

13. A method for a first user equipment (UE) in sidelink communication, the method comprising: receiving a first radio signal from a second UE using at least one first antenna; determining a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; Based on the determined first direction, select a beam from a plurality of beams for communicating with the second UE; as well as A second radio signal is transmitted to the second UE on the selected beam using at least one second antenna.

14. The method according to claim 13, wherein: The at least one first antenna is a plurality of omnidirectional antennas, and the at least one second antenna is at least one directional antenna.

15. The method according to claim 13, wherein: The communication is a directional communication between the first UE and the second UE.

16. The method according to claim 13, further comprising: Prior to selecting the beam from among the plurality of beams, a direction of the beam from the at least one second antenna relative to a coordinate system of the at least one second antenna is determined based at least on the determined first direction associated with the received first radio signal.

17. The method according to claim 13, wherein: The first received radio signal comprises location information providing the location of the second UE.

18. The method according to claim 13, wherein: The at least one first antenna includes a plurality of first antennas, and the angle of arrival of the received first radio signal is estimated based on a comparison of phases of the first radio signal received at two or more antennas among the plurality of first antennas.

19. The method according to claim 13, wherein: The received angle of arrival of the first radio signal at the first UE comprises at least one of: an angle between an x-axis and an incoming first radio signal direction, or an angle between a y-axis and the incoming first radio signal direction.

20. A non-transitory computer readable medium storing instructions executable by one or more processors of a first user equipment (UE) for communication to perform a method comprising: receiving a first radio signal from a second UE using at least one first antenna; determining a first direction associated with the received first radio signal based on an estimated angle of arrival of the received first radio signal at the first UE; Based on the determined first direction, select a beam from a plurality of beams for communicating with the second UE; as well as A second radio transmission is transmitted to the second UE on the selected beam using at least one second antenna.

Images