Control device, wireless communication system, and control method

Abstract

This control device comprises: a control unit that, on the basis of a first direction toward a wireless communication device from an antenna device which relays a signal transmitted to the wireless communication device, determines control information for controlling relay in the antenna device; and a transmission unit that transmits the control information to the antenna device.

Description

Control device, wireless communication system, and control method

[0001] The present disclosure relates to a control device, a wireless communication system, and a control method.

[0002] The 3rd Generation Partnership Project (3GPP) has developed specifications for the 5th generation mobile communication system (5G, also known as New Radio (NR) or Next Generation (NG)), and is also developing specifications for the next generation, known as Beyond 5G, 5G Evolution, or 6G.

[0003] In NR, in addition to user terminals (which may be referred to as UE (User Equipment) or simply as terminals) and radio base stations (which may be simply referred to as base stations), the introduction of radio devices such as RIS (Reconfigurable Intelligent Surface) is being considered to achieve higher data rates and wider coverage (see, for example, Patent Document 1).

[0004] International Publication No. 2022 / 151016

[0005] However, there is room for further consideration regarding control of relay operations in wireless devices whose introduction is being considered.

[0006] One aspect of the present disclosure provides a control device, a wireless communication system, and a control method that can appropriately control relay operations in wireless devices whose introduction is being considered.

[0007] A control device according to one aspect of the present disclosure includes a control unit that determines control information for controlling relaying in the antenna device based on a first direction from an antenna device that relays a signal to be transmitted to a wireless communication device toward the wireless communication device, and a transmitting unit that transmits the control information to the antenna device.

[0008] 1-1-1-2. FIG. 1-1-2 shows an example of a precoder according to an embodiment of the present disclosure. FIG. 1-1-3 shows an example of a reference point. FIG. 1-1-4 shows an example of a uniform grid in Cartesian coordinates. FIG. 1-1-5 shows an example of a method for beam sweeping between a TRP and a UE. FIG. 1-1-6 shows an example of a control scheme in an embodiment. FIG. 1-1-7 shows an example of a method for beam sweeping between a RIS-MT and a UE. FIG. 1 is a diagram showing an example of an incident / reflection angle table showing the correspondence relationship between the incident angle and the reflection angle in the RIS. FIG. 2 is a diagram showing an example of option 1 for UE coordinate estimation. FIG. 3 is a diagram showing an example of option 2 for UE coordinate estimation. FIG. 4 is a sequence diagram showing the processing flow of option 2 for RIS beam control in an embodiment. FIG. 5 is a block diagram showing an example of the configuration of a base station according to an embodiment of the present disclosure. FIG. 6 is a block diagram showing an example of the configuration of a terminal according to an embodiment of the present disclosure. FIG. 7 is a block diagram showing an example of the configuration of a wireless device according to an embodiment of the present disclosure. FIG. 8 is a diagram showing an example of the hardware configuration of a base station, a terminal, and a wireless device according to an embodiment of the present disclosure. FIG. 9 is a diagram showing an example of the configuration of a vehicle.

[0009] An embodiment according to one aspect of the present disclosure will be described below with reference to the drawings. Note that the embodiment described below is an example, and the embodiment to which the present disclosure is applied is not limited to the following embodiment.

[0010] In operation of the wireless communication system according to the embodiment of the present disclosure, existing technology is used as appropriate, for example, existing LTE or existing NR, but is not limited to existing LTE or NR.

[0011] Furthermore, in the embodiments of the present disclosure described below, terms used in existing LTE or NR, such as SS (Synchronization signal), PSS (Primary SS), SSS (Secondary SS), PBCH (Physical broadcast channel), PRACH (Physical random access channel), PDCCH (Physical Downlink Control Channel), PDSCH (Physical Downlink Shared Channel), PUCCH (Physical Uplink Control Channel), and PUSCH (Physical Uplink Shared Channel), are used. This is for convenience of description, and similar signals, functions, etc. may be referred to by other names. Furthermore, the above-mentioned terms in NR correspond to NR-SS, NR-PSS, NR-SSS, NR-PBCH, NR-PRACH, etc. However, even signals used in NR are not necessarily referred to as "NR-".

[0012] Furthermore, in the embodiments of the present disclosure, the duplex method may be a time division duplex (TDD) method, a frequency division duplex (FDD) method, or another method (for example, flexible duplex, etc.).

[0013] Furthermore, in the embodiments of the present disclosure, "configuring" radio parameters and the like may mean that predetermined values ​​are pre-configured, or that radio parameters notified from a base station or a terminal are set.

[0014] <Wireless Communication System> Fig. 1 is a diagram illustrating an example of a wireless communication system 10 according to an embodiment of the present disclosure. The wireless communication system 10 is a wireless communication system conforming to 5G NR or 6G NR, and includes a Next Generation-Radio Access Network 20 (hereinafter, NG-RAN 20) and a terminal 200 (hereinafter, also referred to as UE (User Equipment) 200).

[0015] The wireless communication system 10 may be a wireless communication system conforming to a system called Beyond 5G, 5G Evolution, or 6G.

[0016] The NG-RAN 20 includes a base station 100 (hereinafter also referred to as a gNB 100). Note that the number of gNBs and UEs is not limited to the example shown in FIG. 1 .

[0017] The NG-RAN 20 actually includes multiple NG-RAN nodes, specifically, gNBs (or ng-eNBs), and is connected to a core network conforming to 5G or 6G. The NG-RAN 20 and the core network may be simply referred to as a "network." In the following description, the term "gNB" may be replaced with "network (NW)."

[0018] As an example, gNB100 is a base station conforming to 5G or 6G and performs wireless communication conforming to 5G or 6G with UE200.

[0019] 1 also shows a radio device 300 that transfers signals between the gNB 100 and the UE 200. Hereinafter, the radio device 300 may be referred to as a RIS (Reconfigurable Intelligent Surface).

[0020] For example, the radio device 300 performs a forwarding operation of forwarding a signal transmitted from the gNB 100 to the UE 200. The radio device 300 may also perform a forwarding operation of forwarding a signal transmitted from the UE 200 to the gNB 100. Note that "forward" may be replaced with "relay." Furthermore, "operation" may be replaced with "processing," "control," or the like. Furthermore, a RIS, which is an example of the radio device 300 under consideration in NR, will be described below.

[0021] The gNB 100 and the UE 200 may support MIMO (Multiple-Input Multiple-Output), which generates more directional beams by controlling radio signals transmitted from multiple antenna elements, carrier aggregation (CA), which bundles and uses multiple component carriers (CC), and dual connectivity (DC), which communicates between the UE and each of two NG-RAN nodes.

[0022] The wireless communication system 10 may also support multiple frequency ranges (FR). The wireless communication system 10 may support FR1 and FR2. The frequency bands of each FR are, for example, as follows: FR1: 410 MHz to 7.125 GHz FR2: 24.25 GHz to 52.6 GHz

[0023] FR1 may use a sub-carrier spacing (SCS) of 15 kHz, 30 kHz, or 60 kHz, and a bandwidth (BW) of 5 to 100 MHz. FR2 is a higher frequency than FR1, and may use an SCS of 60 kHz or 120 kHz (including 240 kHz), and a bandwidth (BW) of 50 to 400 MHz.

[0024] Note that SCS may be interpreted as numerology, which is defined in 3GPP TS 38.300 and corresponds to one subcarrier spacing in the frequency domain.

[0025] Furthermore, the wireless communication system 10 may support a frequency band higher than the FR2 frequency band. Specifically, the wireless communication system 10 may support a frequency band exceeding 52.6 GHz up to 114.25 GHz. For convenience, such a high frequency band may be referred to as "FR2x." When using a frequency band exceeding 52.6 GHz, CP-OFDM (Cyclic Prefix-Orthogonal Frequency Division Multiplexing) / DFT-S-OFDM (Discrete Fourier Transform-Spread-Orthogonal Frequency Division Multiplexing) with a larger SCS may be applied.

[0026] The time direction (t) may be called a time domain, a symbol period, a symbol time, etc. The frequency direction may be called a frequency domain, a resource block, a subcarrier, a bandwidth part (BWP), etc.

[0027] The gNB 100 transmits control information, configuration information, etc. of the gNB 100 to the UE 200 as a downlink (DL) signal.

[0028] Furthermore, for example, gNB100 receives control information, data signals, information regarding the processing capabilities of UE200 (terminal capabilities (information); for example, UE capability), etc. from UE200 as uplink (UL) signals.

[0029] Radio device 300 performs a forwarding operation to forward a DL signal to UE 200. Radio device 300 also performs a forwarding operation to forward a UL signal to gNB 100. Note that, hereinafter, the UL signal that gNB 100 receives from UE 200 and / or the DL signal that UE 200 receives from gNB 100 may be a signal forwarded by radio device 300.

[0030] The radio device 300 may be divided into an antenna panel that reflects, refracts, etc., signals as a forwarding operation of DL signals and / or UL signals, and a control device that controls the antenna panel. The antenna panel may be replaced with terms such as an antenna unit or an antenna device. The antenna panel may also be referred to as a relay device. In this case, the antenna panel may be connected to the control device by wire or wirelessly. In this case, the control device may have a communication function and communicate with the gNB 100 and / or the UE 200. In this case, the antenna panel may be controlled by the control device or by the gNB 100. For example, the gNB 100 may determine control information for controlling the antenna panel and control the antenna panel by transmitting the determined control information to the control device.

[0031] The UE 200 is a communication device equipped with a wireless communication function, such as a smartphone, a mobile phone, a tablet, a wearable terminal, or an M2M (Machine-to-Machine) communication module.

[0032] The UE 200 receives a control signal or a data signal from the gNB 100 via DL and transmits a control signal or a data signal to the gNB 100 via UL, thereby utilizing various communication services provided by the wireless communication system 10. The UE 200 also receives various reference signals transmitted from the gNB 100 and performs measurement of propagation path quality based on the reception results of the reference signals.

[0033] Channels used for transmitting DL signals include, for example, data channels and control channels. For example, the data channel may include a physical downlink shared channel (PDSCH), and the control channel may include a physical downlink control channel (PDCCH). For example, the gNB 100 transmits control information to the UE 200 using the PDCCH, and transmits DL data signals using the PDSCH. Note that the PDSCH is an example of a downlink shared channel, and the PDCCH is an example of a downlink control channel. Note that the PDCCH may be interpreted as downlink control information (DCI), control information, etc. transmitted in the PDCCH.

[0034] The reference signal included in the DL signal may include, for example, at least one of a DMRS (Demodulation Reference Signal), a PTRS (Phase Tracking Reference Signal), a CSI-RS (Channel State Information - Reference Signal), an SRS (Sounding Reference Signal), and a PRS (Positioning Reference Signal) for position information. For example, reference signals such as the DMRS and PTRS are used to demodulate DL data signals and are transmitted using the PDSCH.

[0035] Channels used for transmitting UL signals include, for example, data channels and control channels. For example, the data channel may include a Physical Uplink Shared Channel (PUSCH), and the control channel may include a Physical Uplink Control Channel (PUCCH). For example, the UE 200 transmits control information using the PUCCH and transmits UL data signals using the PUSCH. Note that the PUSCH is an example of an uplink shared channel, and the PUCCH is an example of an uplink control channel. The shared channel may also be called a data channel. Note that the PUSCH or the PUCCH may be interpreted as uplink control information (UCI), control information, etc. transmitted in the PUSCH or the PUCCH.

[0036] The reference signals included in the UL signal may include, for example, at least one of DMRS, PTRS, CSI-RS, SRS, RS, and PRS for location information. For example, the reference signals such as DMRS and PTRS are used to demodulate the UL data signal and are transmitted using the PUSCH.

[0037] <Utilization of Sub-Terahertz Waves> Future wireless communication systems (e.g., 6G and beyond) have introduced stringent requirements regarding capacity, coverage, power consumption, and other aspects. Utilizing the sub-terahertz (e.g., 100 GHz to 300 GHz) spectrum, which is a higher frequency band than existing systems (e.g., NR Rel. 15 / 16 / 17), is being considered to achieve a data rate of 100 Gbps while maintaining sufficient coverage.

[0038] Among these, the design of a line of sight (LOS)-MIMO (Multi-Input Multi-Output) transmission method suitable for access links is being considered, with the goal of 100 GHz, 100 Gbps, and 100 m (coverage).

[0039] 2A is a diagram showing an example of a distant user in a high frequency band, in which orthonormal transmission is not possible for the distant user due to the size limitations of the mega-MIMO base station (BS).

[0040] 2B illustrates an example of a non-line-of-sight (NLOS) user in the high frequency band, where blockages (e.g., buildings) prevent efficient LOS-MIMO transmission to the non-line-of-sight user.

[0041] Existing NR MIMO (NR MIMO) does not support LOS-MIMO. Existing NR requires a very large bandwidth to achieve a data rate of 100 Gbps, which is difficult to secure.

[0042] NR MIMO is designed for antenna far-field applications, supporting only rank-1 transmission per polarization direction in LOS channels. Using dual polarization enables rank-2 multiplexing, but ranks higher than this are not available. Achieving 100 Gbps requires a bandwidth of several tens of GHz, which is difficult to achieve in practical systems and places high demands on RF components.

[0043] The LOS-MIMO schemes already considered require fixed transmitting and receiving positions, making them unsuitable for access links or requiring too large array sizes.

[0044] For this reason, the introduction of fixed widely spaced antenna arrays, Orbital Angular Momentum (OAM)-MIMO, and Reconfigurable Intelligent Surface (RIS)-aided Mega MIMO are being considered.

[0045] Not limited to the above-mentioned example of sub-terahertz waves, RIS has attracted much attention as a new device for network deployment due to its flexible and cost-effective approach. RIS enables the achievement of very high data rates and wide coverage extension, and is being considered as a promising technology within the topology of 6G wireless networks. For example, RIS is being considered in 3GPP Release 19 (Rel. 19).

[0046] <Reconfigurable Intelligent Surface (RIS)> A RIS relays communications between a BS and a UE by controlling the reflection angle in at least one of a backhaul link to an access link and a backhaul link. The RIS is an example of a wireless device for implementing a flexible and cost-effective approach to network deployment compared to new types of network (NW) nodes such as an Integrated Access and Backhaul (IAB), an RF repeater, and an NCR (Network-controlled Repeater).

[0047] The RIS may be composed of a number of reconfigurable scattering components, hereinafter sometimes referred to as elements or antenna elements.

[0048] The RIS may control the direction of the reflected signal or the direction of the transmitted (refracted) signal.

[0049] In the present disclosure, reflection, transmission, and refraction may be interpreted as interchangeable terms. Furthermore, in the present disclosure, reflection, transmission, and refraction of a signal at a RIS may be understood as the RIS receiving a signal transmitted from a specific direction and transmitting (or receiving) a signal in the same direction as the specific direction or in a direction different from the specific direction. In this case, the signal transmitted by the RIS may be the same signal as the signal received by the RIS, or may be a signal received by the RIS that has been subjected to specific processing. Furthermore, in the present disclosure, forwarding processing at a RIS may be understood as processing in which at least one of reflection, transmission, and refraction occurs at the RIS.

[0050] While the NCR amplifies the signals it relays, the RIS may not require an RF amplifier, which can reduce power consumption.

[0051] While the RIS can obtain beam gain with narrowband beams, an increase in the number of RIS beams (beams reflected / refracted by the RIS) is required.

[0052] The RIS may reflect / refract signals other than the target frequency.

[0053] The RIS may be made of a material such as a liquid crystal, a metal, a semiconductor, etc. For example, a RIS using a liquid crystal has a slower beam sweep speed than a semiconductor, and is therefore considered unsuitable for current beam sweep operations.

[0054] Due to its thin and flexible shape, the RIS may be installed on an object such as a building.

[0055] 3A is a diagram showing an example of communication using the NCR configuration. The NCR may include an NCR-mobile termination (MT) and an NCR-forwarding (Fwd). The NCR-MT communicates with the BS (gNB) via a control link.

[0056] The communication between the NCR-MT and the BS may include at least one of receiving configuration / instruction / control information from the BS and sending requests / reports / responses to the BS. The NCR-Fwd relays communications between the BS and the UE by relaying / amplifying signals from the backhaul link to the access link and from the access link to the backhaul link.

[0057] In addition, the RIS may also include a configuration for communicating with a BS (gNB), similar to the NCR. In the RIS, the configuration for communicating with a BS (gNB) may be referred to as a RIS-MT. In other words, similar to the NCR, the RIS may also have a RIS-MT and a RIS-Fwd. Furthermore, the RIS-Fwd may simply be referred to as a RIS. In the following description, the operation of the RIS may be regarded as the operation of the RIS-Fwd or as the operation of the RIS-MT. The RIS-MT is not limited to an example in which communication is performed with a BS, and may also communicate with a UE.

[0058] 3B is a diagram illustrating an example of communication using a RIS, in which the RIS relays communication between a BS and a UE by controlling a reflection angle in at least one of a reflection from a backhaul link to an access link and a reflection from the access link to the backhaul link.

[0059] <System Architecture Including RIS> Fig. 4 is a diagram showing an example of a system architecture including a RIS. Below, a system architecture including a RIS will be described with reference to Fig. 4, but this is merely an example.

[0060] A system architecture including a RIS may include multiple (eg, two) design phases.

[0061] For example, a system architecture including a RIS may include an aperture pre-adaptation phase.

[0062] In the aperture pre-adaptation phase, UE positioning may be performed first. In the UE positioning, the UE may report information about its position / attitude to the network (NW). In addition, in the UE positioning, the NW (base station) may estimate information about the UE's position / attitude based on a signal (e.g., UL RS) transmitted from the UE.

[0063] Note that UE positioning in the aperture pre-adaptation phase may be omitted.

[0064] Then, in an aperture pre-adaptation phase, pre-adaptation of the apertures (eg, antenna elements) of the RIS may be performed.

[0065] In this disclosure, aperture adaptation may mean determining / determining / selecting which antenna elements / arrays to use.

[0066] Then, in an aperture pre-adaptation phase, pre-adaptation of the aperture (eg, antenna elements) of the BS may be performed.

[0067] A system architecture including a RIS may also include a beamforming phase.

[0068] The beamforming phase may, for example, follow an aperture pre-adaptation phase.

[0069] In the beamforming phase, beamforming may be performed first at the BS.

[0070] Then, in the beamforming phase, beamforming in the RIS may be performed.

[0071] Reception may then occur in the beamforming phase by the UE, which may use a CSI reception (CSIR) based MIMO receiver.

[0072] Note that reception by the UE in the beamforming phase may be omitted.

[0073] <Far field and near field beamforming method> Fig. 5 is a diagram showing an example of the near field (NF) and far field (FF) of a RIS. Fig. 5 illustrates an RIS array, and examples of radio wave propagation in the near field and far field relative to the RIS array. Note that the RIS array may be considered as an example of a surface in the RIS that transmits signals or a surface that emits radio waves. Furthermore, the near field may be replaced with a short distance. Furthermore, the far field may be replaced with a long distance.

[0074] A large aperture in a RIS exhibits certain characteristics that enhance the range of the near field. For example, as shown in FIG. 5 , the near field boundary (e.g., the boundary between the near field and the far field) is proportional to the square of D, where D represents the size associated with the RIS aperture. Therefore, a large aperture in a RIS enhances the range of the near field. Furthermore, the near field boundary is inversely proportional to the wavelength λ, so the shorter the wavelength, i.e., the higher the frequency, the greater the range of the near field. Within this near field region, the phase delays for the various elements of the RIS become distinguishable. As a result, the assumption of a plane wavefront is no longer valid; spherical wavefronts must be considered. As shown in FIG. 5 , within the far field region, the radio waves emitted from each element of the RIS are assumed to be plane waves, whereas within the near field region, the wavefronts of the radio waves emanating from each element are spherical.

[0075] Several methods are being investigated as existing far-field (FF) and near-field (NF) beamforming methods.

[0076] For example, the beamforming method may be DFT-based beamforming (BF), beamfocusing with optimum phase, and beamfocusing with near-field (NF) steering vector.

[0077] The DFT-based BF may be used primarily for transmitting signals to terminals at long distances, and may use a precoder (matrix) based on an angle-dependent linear phase.

[0078] Figure 6A shows an example of DFT-based beamforming (BF) for a uniform, linear array, where x is the distance from the array center to element n in the array and the angle of the beam with respect to the axis normal to the array.

[0079] Beam focusing with optimal phase may be used primarily for transmitting signals to terminals at short distances, and may use a precoder (matrix) based on a position (distance)-dependent non-linear phase.

[0080] Figure 6B shows an example of beam focusing with optimal phase, showing an example of a uniform linear array, where DF is the focal length and x' is the distance from the axis normal to the array to the focal point.

[0081] Beam focusing with short-range steering vectors may be used primarily for transmitting signals to short-range terminals. Beam focusing with short-range steering vectors may use a precoder (matrix) based on angle- and position (distance)-dependent quadratic phase.

[0082] Figure 6C shows an example of beam focusing with near-field (NF) steering vectors, showing an example of a uniform linear array, where D is the distance from the center of the array to the focal point, and ω is the angle from the axis normal to the array to the line connecting the array center and the focal point.

[0083] Conventional codebooks for far-field beamforming, such as DFT codebooks, cannot be directly applied to near-field beamforming due to a mismatch with the near-field channel. If DFT codebooks were applied to near-field beamforming, it could cause severe SNR loss. On the other hand, focused beamforming, such as ring-type codebooks (RTC), a near-field version of coherent beamformers, does not have the near-field limitation.

[0084] For example, RIS is employed for data channel transmission, and the RTC described above generates a UE-specific focused beam, enabling high-speed transmission.

[0085] On the other hand, the adoption of RIS for the transfer of control channels (for example, SSB (Synchronization Signal Block) and the like) is being considered.

[0086] 7 is a diagram showing an example of SSB forwarding using RIS. In FIG. 7, it is shown that RIS forwards SSBs #2 to #4 of SSBs #0 to #4 transmitted by the gNB.

[0087] When the RIS transmits a control channel (for example, SSB, etc.), it is considered to transmit the control channel by expanding the beam.

[0088] Here, we will describe existing methods of SSB transmission over RIS and existing RIS beam expansion techniques.

[0089] <Existing Methods> The following describes existing methods for transmitting SSBs by a RIS. In existing methods, the RIS uses multiple narrow beams to transmit SSBs transmitted by a gNB. Therefore, existing methods require significant allocation of SSB resources or significant changes to the SSB scheme.

[0090] Existing typical beam expansion techniques can be classified into numerical optimization algorithm-based techniques, aperture adjustment-based techniques, logical subarray division-based techniques, and wide-area illumination approaches.

[0091] For example, in technologies based on numerical optimization algorithms, the algorithms are complex, which makes the processing complicated, making it difficult to achieve beamforming in a realistic time frame.

[0092] Also, for example, with high-pass illumination approaches, it is difficult to precisely control the shaping of the wide beam pattern of the RIS according to the actual coverage requirements.

[0093] Also, for example, aperture-adjustment based techniques reduce the beamforming gain of the array due to the aperture adjustment.

[0094] Furthermore, for example, in a technology based on logical subarray division, the beamforming gain across the entire area varies significantly.

[0095] Here, examples of related techniques for RIS including aperture adjustment and logical sub-array division will be described.

[0096] <First Example of Related Art> The first example relates to codebook / precoder design.

[0097] The codebook / precoder may be a codebook / precoder for short distance (NF) or a codebook / precoder for long distance (FF).

[0098] In the present disclosure, a short distance may mean a distance less than (or equal to or less than) a certain threshold. In the present disclosure, a long distance may mean a distance greater than (or equal to or greater than) a certain threshold.

[0099] The RIS (RIS-NCR) may receive information for the precoder / codebook from the NW. The information may be, for example, information about the location of another node (e.g., a UE / NW node). The information about the location may be, for example, information about angle and / or information about distance.

[0100] The first example is roughly divided into examples 1-1 and 1-2. Either example 1-1 or example 1-2 may be applied, or a combination of examples 1-1 and 1-2 may be applied.

[0101] Example 1-1 Example 1-1 relates to a specific codebook / precoder design.

[0102] Example 1-1 is broadly divided into Examples 1-1-1 to 1-1-4. Any one of Examples 1-1-1 to 1-1-4 may be applied, or at least two of Examples 1-1-1 to 1-1-4 may be applied in combination.

[0103] The precoder may be calculated, for example, as the output of a particular multiplication of different precoders / matrices.

[0104] In the present disclosure, the terms codebook, precoder, codeword, matrix, term, vector, and element may be interchangeable.

[0105] <Example 1-1-1> The precoder in the RIS may be a precoder that decouples angle-dependent terms and distance (position)-dependent terms.

[0106] Example 1-1-1 may be used, for example, for beamforming / focusing of NCR including RIS (RIS-NCR).

[0107] The precoder in the RIS may be calculated, for example, by the product (e.g., Hadamard product, e.g., element-by-element product) of a distance-dependent precoder / matrix (e.g., WRing) and an angle-dependent precoder / matrix (e.g., WDFT).

[0108] For example, the precoder may be calculated using the following equation 1.

[0109] Here, D Ｆ may be the axial distance between the array and the focal position.

[0110] In the present disclosure, a phase shift associated with a distance-dependent precoder may be referred to as a ring-type phase distribution, and a codebook associated with a distance-dependent precoder may be referred to as a ring-type codebook (RTC).

[0111] FIG. 8 is a diagram illustrating an example of a precoder according to Example 1-1-1. An example of a uniform and linear array is shown in FIG. 8. In the example shown in FIG. 8, beam focusing at the boresight is performed first. The above-described distance-dependent precoder may be used for the beam focusing. k is an index corresponding to the phase in the DFT.

[0112] In the example shown in Figure 8, the focal position is then shifted by the DFT vector, which may utilize the angle-dependent precoder described above.

[0113] According to Example 1-1-1, by using angle-dependent terms and distance (position)-dependent terms, signals can be transmitted appropriately to targets at long and short distances, and implementation is also easy.

[0114] <Example 1-1-2> The precoder in the RIS may be a precoder that uses piecewise linear approximation with DFT vectors.

[0115] For example, the precoder may be a precoder that includes a term for each subarray (one or more arrays) and a distance (position) dependent term.

[0116] Example 1-1-2 may be used, for example, for beamforming / focusing of NCR with RIS (RIS-NCR) and / or coherent transmission of multiple panels (e.g., widely spaced panels).

[0117] Moreover, Example 1-1-2 is suitable for subarray-based RIS-NCR.

[0118] The precoder in the RIS may be calculated by, for example, the product (for example, the Hadamard product (for example, the product of each element)) of a precoder for each subarray (one or more arrays) and an angle-dependent precoder.

[0119] The precoder for each subarray (one or more arrays) may be expressed, for example, as the product of a phase offset for each subarray and an angle offset of the subarray.

[0120] For example, the precoder may be calculated using the following equation 2.

[0121] where φ （ｉ，ｊ） ＰＯ may represent the phase offset of subarray (i, j). The phase offset of subarray (i, j) may be quantized with specific bits (e.g., b bits) that can take on specific values ​​(e.g., values ​​from 0 to 2π). （ｉ，ｊ） ＡＯ may denote the angular offset of subarray (i,j).

[0122] W(i,j)AO may be calculated based on the dot product of the vector from the array reference point to the subarray (i,j) reference point and the vector from the subarray (i,j) reference point to antenna element (m,n) in subarray (i,j).

[0123] For example, W （ｉ，ｊ） ＡＯ may be calculated using the following equation 3:

[0124] where D may be the distance from the array (e.g., the reference point of the array) to the object (e.g., the UE). （ｉ，ｊ） ＳＡ denotes the vector from the reference point of the array to the reference point of the subarray (i,j), and r （ｍ，ｎ） ＡＥmay denote the vector from the reference point of subarray (i,j) to antenna element (m,n) in subarray (i,j) (see FIG. 9).

[0125] Fig. 10 is a diagram showing an example of a precoder according to Example 1-1-2. Fig. 10 shows an example of a uniform and linear array. In the example shown in Fig. 8, first, beam direction focusing is performed for multiple arrays (each subarray) using phase offsets (Step 1). For this beam focusing, a precoder based on the above-described phase offset and angle offset may be used.

[0126] In the example shown in Figure 10, the focal position is then shifted by the DFT vector (step 2), which may utilize the angle-dependent precoder described above.

[0127] According to Example 1-1-2, by using a term for each subarray (one or more arrays) and a distance (position) dependent term, it is possible to transmit a signal appropriately to targets at long and short distances.

[0128] <Example 1-1-3> The precoder in the RIS may be a precoder that uses a term related to short distance and a term related to long distance.

[0129] Examples 1-1-3 may be used, for example, to acquire CSI in either or both of FF and NF (not limited to FF and NF), or may be used for localization / sensing of NF.

[0130] The precoder in the RIS may be calculated by, for example, multiplying a first precoder and a second precoder (e.g., a Kronecker product (e.g., an element-wise product)). The first / second precoder may include a term corresponding to a long distance (or angle dependency) and a term corresponding to a short distance (or distance dependency).

[0131] The precoder in this example may be applied in a uniform planar array.

[0132] For example, the precoder W may be expressed by the following equation 4.

[0133] where W is the first precoder W Ｎ＿１，Ｏ＿１，ｋ＿１，Ｄ，Ｌ＿１ and the second precoder W Ｎ＿２，Ｏ＿２，ｋ＿２，Ｄ，Ｌ＿２ It should be noted that "N_1" is expressed as the Kronecker product of "N １ ". Other notations other than "N_1" may also be expressed in the same way as "N_1".

[0134] W Ｎ＿ｉ，Ｏ＿ｉ，ｋ＿ｉ，Ｄ，Ｌ＿ｉ may be expressed, for example, by the following Equation 5:

[0135] Here, the number of antenna elements (scattering elements) in the i-th axial direction in the RIS array is N ｉ and the number of oversamplings in the i-th axis direction O ｉ may be the same as the NR DFT-based codebook defined in the existing NR. i=1 may correspond to the x-axis direction (horizontal direction). i=2 may correspond to the z-axis direction (vertical direction). Also, k ｉ is the codeword index, and k′ may represent a quadratic term.

[0136] Also, N ＲＰ may be a value that depends on the reference point of the RIS array. For example, N ＲＰ is N ＲＰ = 2(d ＲＰ -d ０ ) / Δd.

[0137] For example, d ＲＰ -d ０ may denote the distance between a particular antenna element (e.g., antenna element #0) and the reference point, and Δd may denote the antenna element spacing.

[0138] For example, if the bottom leftmost element of the array is used as the reference point, then N ＲＰ may be 0.

[0139] For example, if the center coordinate of the array is used as the reference point, N ＲＰ is N ｉ It may be calculated as -1.

[0140] D may represent the normalized distance between the reference point and the focal length, for example, D may be calculated as (focal length) / λ.

[0141] L may be a value related to a normalized equivalent aperture, and may be calculated, for example, as ON·Δd / λ.

[0142] <Example 1-1-4> The precoder in the RIS may be a precoder that uses a precoder for an access link (between the UE and the RIS) and a precoder for a backhaul link (between the BS and the RIS).

[0143] For example, the precoder may be a precoder that includes a term for each subarray (one or more arrays) and a distance (position) dependent term.

[0144] Examples 1-1-4 may be used, for example, for beamforming / focusing of NCR with RIS (RIS-NCR) on the backhaul link / access link, and / or cascaded LoS-MIMO (e.g., LoS-MIMO requiring joint focal points indication).

[0145] The precoder in the RIS may be calculated, for example, by the product (e.g., Hadamard product, e.g., element-by-element product) of the precoder for the access link and the precoder for the backhaul link.

[0146] For example, the precoder may be calculated using the following equation 6.

[0147] Here, W ＡＣ may represent the precoder of the beam (access beam, beam for UE) in the access link of RIS-NCR. ＢＨ may denote the precoder of the beam (backhaul beam, beam for BS) in the backhaul link of RIS-NCR.

[0148] W ＡＣ and W ＢＨ At least one of may be, for example, a precoder calculated by at least one of the methods described in Examples 1-1-1 to 1-1-3 above.

[0149] W ＡＣ and W ＢＨ The focal lengths of W may be selected / determined independently or jointly. ＡＣ and W ＢＨ The focal lengths of may be selected / determined in a conjugate symmetric manner.

[0150] According to Example 1-1-4, it is possible to appropriately design the precoder / codebook not only in the access link but also in the backhaul link.

[0151] <Parameters Related to Codebook / Precoder> The parameters of the formulas in Example 1-1 above will be described below.

[0152] L may be a parameter related to an aperture (e.g., an antenna element), and may be reported as the capability of the RIS-NCR (NCR-MT).

[0153] L may be reported by the RIS, for example, as antenna number / spacing in n dimensions (eg, n is 2).

[0154] L may be reported by the RIS, for example, as the length of a side of the RIS (eg, antenna number x antenna spacing).

[0155] N ｉ , O ｉ , k ｉ , k ｉｐ , D ｉ (i=1 or 2) may be a parameter related to the codebook of the access link / backhaul link.

[0156] N ｉ and O ｉ may be related to a codebook of the RIS, which may be preset for the RIS or may be predefined in the specification.

[0157] N ｉ and O ｉ may be determined based on reports on the capabilities of the RIS or may be determined independently of the dimensions of the RIS.

[0158] k ｉ may be related to a codebook of the RIS, which may be indicated to the RIS.

[0159] k ｉｐ may be calculated at the RIS based on specific settings / instructions for the RIS.

[0160] D ｉ (e.g., i=1) may be a parameter related to the distance between the BS and the RIS. ｉ (eg, i=2) may be a parameter related to the distance between the UE and the RIS.

[0161] For example, D １ may be pre-configured by the BS for the RIS, or D ２ may be indicated by the BS to the RIS.

[0162] For example, D １ and D ２ may be commanded by the BS (using a compound CW).

[0163] For example, D １ may be pre-configured by the BS for the RIS, or D ２ may be measured by RIS.

[0164] For example, D １ and D ２ may be measured by RIS.

[0165] For example, D １ and D ２ Logarithmic quantization may be used to determine .

[0166] N ＲＰ may be a parameter related to the reference point of the RIS. ＲＰmay be, for example, a parameter relating to the offset of the reference point of the RIS.

[0167] N ＲＰ may be related to a codebook of the RIS, which may be indicated to the RIS.

[0168] A reference point in a RIS may refer to a specific location.

[0169] For example, the reference point for the RIS may be the location of an antenna / subarray at a particular location (eg, the bottom left most).

[0170] For example, the reference point for the RIS may be the location of the center point of the RIS, which is appropriate for a single large RIS or multiple separate sub-arrays.

[0171] For example, the reference point of the RIS may be reported by the RIS. The reference point of the RIS may be determined according to the reference point reported by the RIS.

[0172] A parameter indicating an adaptation (aperture adaptation) mode may be defined, which may be used for aperture control of the RIS.

[0173] The parameter indicating the adaptation mode may be associated with a codebook of the RIS, which may be indicated to the RIS.

[0174] Parameters may be defined that indicate the shape / size of the RIS, which may be used to control the aperture of the RIS.

[0175] A parameter indicating the shape / size of the RIS may be associated with a codebook of the RIS, which may be indicated to the RIS.

[0176] The parameter may be indicated by a bitmap. Alternatively, the parameter may be indicated by the direction and length of two sides of an aperture forming a parallelogram. Alternatively, the parameter may be indicated by the arrangement of subarrays (e.g., direction / spacing / subarray number / subarray size). Alternatively, the parameter may be indicated by at least one of the direction / length of two sides of an aperture forming a parallelogram (which may be called a general mode), the subarray number (sampling rate), and the subarray size.

[0177] A parameter may be defined that indicates the roll-off factor.

[0178] Parameters for a conjugate symmetric RTC may be defined, which may be parameters for a reference point related to the location of the UE.

[0179] A reference point with respect to the location of a UE may refer, for example, to an antenna port (e.g., antenna port #0) of a particular UE.

[0180] The reference point for the UE's location may refer to, for example, a particular (eg, central) UE array established by the BS.

[0181] <Example 1-2> In Example 1-2, quantization of angle (angle information) and distance (distance information) in codebook notification (to NW / RIS-NCR) will be described.

[0182] Example 1-2 is roughly divided into Examples 1-2-1 and 1-2-2. Either of Examples 1-2-1 and 1-2-2 below may be applied, or Examples 1-2-1 and 1-2-2 below may be applied in combination.

[0183] The NW (or RIS-NCR) may transmit angle information / distance information regarding the quantized codebook / precoder using at least one of Examples 1-2-1 and 1-2-2 to the RIS-NCR (or NW).

[0184] <Example 1-2-1> Quantization regarding angles and quantization regarding distances may be performed separately (independently).

[0185] A specific quantization method may be used for the angle. The specific quantization method may be, for example, a DFT-based quantization method. By using a DFT-based method for angle quantization, quantization suitable for a unified design for FF and NF can be performed.

[0186] For example, linear quantization may be used for the distance. Using linear quantization makes it easier to implement in the device. For example, logarithmic quantization may be used for the distance. Using logarithmic quantization allows appropriate quantization regardless of whether the distance between the devices is long or short.

[0187] Quantization of the distance may be performed using Equation 7 below.

[0188] In the present disclosure, the range of NF may be related to the array area, for example, the range of NF may be (approximately) proportional to the array area.

[0189] <Example 1-2-2> Quantization regarding angles and quantization regarding distances may be performed jointly.

[0190] For example, the quantization of angles and distances may use a uniform grid in Cartesian coordinates (angles and distances may be quantized on a uniform grid), which is suitable for use in localization / position-based beam focusing.

[0191] For example, angle and distance quantization may use a non-uniform grid in spherical coordinates (angles and distances may be quantized on a non-uniform grid), which is favorable in terms of aperture / NF range at boresight, and allows for more uniform coverage and fewer beams by using wider beams at close range.

[0192] For example, quantization for angles and distances may be performed using Equation 8 below.

[0193] 11 is a diagram showing an example of a uniform grid in Cartesian coordinates. In the example shown in FIG. 11, a uniform grid in Cartesian coordinates for RIS (RIS-NCR) is shown.

[0194] In FIG. 11, (x ｇｉ , y ｇｉ , z ｇｉ ) may denote the center coordinate of the ith grid obtained from grid index i.

[0195] The uniform grid RTC may be calculated according to at least one of the following options 1 and 2.

[0196] The RTC using a uniform grid may be calculated using Equation 9 below (option 1).

[0197] The RTC using a uniform grid may be calculated using Equation 10 below (option 2).

[0198] Here, the above θ may be calculated using the following equation 11.

[0199] Here, μ may represent the azimuth angle and ν may represent the elevation angle, and μ and ν may be obtained by a specific coordinate transformation.

[0200] According to Example 1-2, it is possible to appropriately quantize the angle (angle information) and distance (distance information) in the notification of the codebook.

[0201] <Second Example of Related Art> The second example relates to aperture adaptation in a RIS.

[0202] The second example is roughly divided into examples 2-1 and 2-2. The following examples 2-1 or 2-2 may be applied, or the following examples 2-1 and 2-2 may be applied in combination.

[0203] The RIS-NCR may receive information (setting information) related to the control of apertures (e.g., antenna elements) from the NW. Based on the information, the RIS-NCR may determine the apertures / antenna elements to be used for signals destined for the terminal.

[0204] <Example 2-1> The RIS (RIS-NCR) may select / decide / determine the aperture to be used from among the apertures included in the RIS.

[0205] Example 2-1 is roughly divided into Examples 2-1-1 and 2-1-2. The following Examples 2-1-1 or 2-1-2 may be applied, or the following Examples 2-1-1 and 2-1-2 may be applied in combination.

[0206] <Example 2-1-1> Unnecessary RIS elements (for example, antenna elements) may be set to off. Information about this setting may be included in information about aperture control received from the NW.

[0207] The unwanted RIS elements may be configured to not scatter (or reflect / refract) the incident signal, or the unwanted RIS elements may be configured to scatter (or reflect / refract) the incident signal in a diffuse or random manner.

[0208] <Example 2-1-2> Beamforming and aperture adaptation may be used in combination.

[0209] The beamforming information may include, for example, information about the beamforming vector of the RIS.

[0210] For example, the (desired and actually used) apertures may be expressed as values ​​(e.g., aperture functions) that indicate the on / off state of each RIS element, and the (desired and actually used) apertures may be applied to the beamforming vectors of that RIS.

[0211] For example, a value (e.g., aperture function) corresponding to a RIS element may indicate that the RIS element is in an OFF state when the value (e.g., aperture function) corresponding to the RIS element is a first value (e.g., 0), and a value (e.g., aperture function) corresponding to the RIS element may indicate that the RIS element is in an ON state when the value (e.g., aperture function) corresponding to the RIS element is a second value (e.g., 1).

[0212] Aperture adaptation may be used to control the beam shape (eg, at least one of the beam width, side lobes, main lobe, and focal spot shape / size).

[0213] <Example 2-2> In Example 2-2, aperture control in RIS (RIS-NCR) will be described.

[0214] Example 2-2 is roughly divided into Examples 2-2-1 and 2-2-2. The following Examples 2-2-1 or 2-2-2 may be applied, or the following Examples 2-2-1 and 2-2-2 may be applied in combination.

[0215] <Example 2-2-1> A mode relating to the aperture of RIS-NCR may be defined.

[0216] The RIS-NCR may determine the aperture to use based on the mode, which may include, for example, first to third modes.

[0217] The first mode may be a mode in which some or all of the elements of the RIS are used in a square configuration, and may be called, for example, a fallback mode.

[0218] The second mode may be, for example, a mode in which some of the elements of the RIS are used in a parallelogram (diamond) shape. The second mode may be, for example, called a semi-continuous mode.

[0219] The third mode may be a mode in which only a specific RIS is used among the RIS elements. The specific RIS may be determined by selecting a portion of the RIS elements in a parallelogram (diamond) shape. The third mode may be called, for example, a discrete mode.

[0220] <Example 2-2-2> The shape / size of the aperture of the RIS-NCR to be used may be instructed in a specific manner. Information regarding the instruction may be included in information regarding aperture control received from the NW.

[0221] For example, the shape / size of the aperture of the RIS-NCR used may be determined by a bitmap / parameter indicating the on / off state of the elements of the RIS used.

[0222] The shape / size of the aperture (e.g., parallelogram (diamond)-shaped aperture) in the second / third mode may be indicated in a specific manner, for example, based on the lengths and angles of two sides relative to a specific point (e.g., a reference point) of the RIS element (selected RIS element).

[0223] In the third mode, the size / number of subarrays to be used may be additionally indicated.

[0224] According to the second example described above, the elements / apertures of the RIS to be used can be appropriately determined / selected.

[0225] <Considerations for this embodiment> In recent years, Beyond 5G / 6G has been studied both domestically and internationally. Higher performance requirements are expected for 6G. In addition, the following various use cases are expected for 6G: - Ultra-extended coverage / ultra-long distance communication - Ultra-large capacity - Ultra-reliable communication - Virtual cell (user centric no cell) - Flexible NW - Mesh NW / Side link It is desirable to design 6G taking these use cases into consideration.

[0226] Toward 6G, the use of high frequency bands and the expansion of coverage are expected. One of the means to achieve this is the use of network controlled repeaters (NCRs) and / or the use of reconfigurable intelligence surfaces (RISs) in base station planning.

[0227] In the following, a configuration in a RIS having a function similar to that of the NCR-MT described above, for example, a function of performing at least one of receiving configuration / instruction / control information from a base station and transmitting a request / report / response to a base station, may be referred to as a RIS-MT. In the following, a configuration in a RIS having a function similar to that of the NCR-Fwd described above, for example, a function of relaying communications between a base station and a UE by relaying / amplifying from a backhaul link to an access link and from an access link to a backhaul link, may be referred to as a RIS-Fwd or RIS. In the following description, "RIS" may be replaced with "RIS-MT" or "RIS-Fwd." Furthermore, when a distinction is made between a RIS and a RIS-MT, the RIS and the RIS-MT may be provided separately and connected to each other by a wire. In this case, however, the RIS-MT has location information of the RIS (e.g., RIS coordinates, RIS altitude) and information on the attitude of the RIS (e.g., tilt angle, rotation angle).

[0228] In the RIS, for example, the RIS-MT may communicate with the UE, and the link through which the communication between the RIS-MT and the UE is performed may be a sidelink or an NR Uu interface.

[0229] One possible means for extending coverage is to provide a RIS at an appropriate position between the base station and the UE to cover areas that cannot be covered by the base station.

[0230] It is naturally desirable that the RIS be installed inside or outside buildings and / or structures such as high-rise buildings (e.g., street canyons), factories, etc., and that the operation be controlled (e.g., control of the reflection angle) to extend coverage depending on the location where it is installed. For example, the RIS is controlled from the perspective of what kind of beam to direct, in what direction, and from what location.

[0231] For example, the RIS forms a beam toward the UE and transmits a signal addressed to the UE. In this transmission operation of the RIS, it is desirable to identify the direction in which the UE is located as seen from the RIS.

[0232] For example, a process called beam sweeping is performed between a transmission / reception point (TRP) and a UE to identify the direction in which the UE is located. The TRP may be replaced with a BS.

[0233] Figure 12 is a diagram showing an example of a beam sweeping method between a TRP and a UE. Figure 12 shows steps (1) to (3) of the beam sweeping procedure between a TRP and a UE, as well as step (4) obtained as a result of the three steps. In Figure 12, the TRP forms a transmit beam and transmits a signal using the transmit beam, and the UE forms a receive beam and receives the signal using the receive beam. In Figure 12, the transmit beam formed by the TRP and the receive beam formed by the UE are shown in different ways.

[0234] In step (1), initial beam selection is performed by beam sweeping of SSBs. For example, the TRP sweeps multiple SSBs in different beam directions. The UE receives the SSBs, measures the reception quality (e.g., received signal strength indicator (RSSI) and signal-to-noise ratio (SNR)), and selects a beam based on the measurement results. In the initial beam selection, a coarse beam is selected.

[0235] For example, in step (1) of Figure 12, the TRP performs beam sweep using transmit beams #1 to #3. The UE performs beam sweep using receive beams #1 to #3. Note that the transmit beams #1 to #3 and receive beams #1 to #3 are beams with relatively wide beam widths, corresponding to coarse beams.

[0236] In step (1) of Fig. 12, transmission beam #2 and reception beam #2 are selected, and the UE reports information indicating the selected beam (transmission beam #2 in the example of Fig. 12) to the TRP.

[0237] In step (2), a second-stage beam is selected by beam sweeping a reference signal (RS) such as a CSI-RS. In the second-stage transmission beam selection, a transmission beam narrower than the transmission beam used in the initial beam selection is selected. For example, in the second-stage transmission beam selection, a transmission beam having a relatively narrow beam width is used, corresponding to the transmission beam with a wide beam width selected by the initial beam selection. For example, the TRP sweeps the RS in different beam directions. The UE receives the RS, measures the reception quality (e.g., signal-to-noise power ratio (SNR)), and selects a beam based on the measurement results.

[0238] For example, in step (2) of Figure 12, the TRP performs beam sweep using transmit beams #2a, #2b, and #2c corresponding to transmit beam #2. The transmit beams #2a, #2b, and #2c corresponding to transmit beam #2 are one or more transmit beams directed in the direction of transmit beam #2 and its vicinity, and have a beam width narrower than the beam width of transmit beam #2. The UE receives a signal (e.g., RS) transmitted from the TRP using the selected receive beam #2.

[0239] In step (2) of Fig. 12, transmission beam #2b is selected from transmission beams #2a, #2b, and #2c, and the UE reports information indicating the selected beam (transmission beam #2b in the example of Fig. 12) to the TRP.

[0240] In step (3), a second-stage reception beam is selected by beam sweeping of the RS (e.g., CSI-RS). In the second-stage reception beam selection, a reception beam narrower than the reception beam used in the initial beam selection is selected. For example, in the second-stage reception beam selection, a reception beam having a relatively narrow beam width is used, corresponding to the reception beam selected in the initial beam selection having a wide beam width.

[0241] For example, in step (3) of Figure 12, the TRP transmits a signal (e.g., RS) using transmit beam #2b. The UE performs beam sweep using receive beams #2a, #2b, and #2c corresponding to receive beam #2. The receive beams #2a, #2b, and #2c corresponding to receive beam #2 are one or more receive beams directed in the direction of receive beam #2 and its vicinity, and have a beam width narrower than that of receive beam #2.

[0242] In step (3) of FIG. 12, reception beam #2b is selected from reception beams #2a, #2b, and #2c.

[0243] The TRP transmits a signal using transmit beam #2b, and the UE receives the signal using receive beam #2b.

[0244] As described above, the beams used by the TRP and the UE are selected by beam sweeping. The direction in which the selected TRP beam is directed corresponds to the direction in which the UE is located (hereinafter, sometimes referred to as the "UE direction"). In this case, the UE direction as seen from the TRP is identified (or estimated) based on the beam selected by beam sweeping.

[0245] Since the RIS performs the operation of forwarding a signal in the direction of the UE as seen from the RIS, it is desirable to specify the direction of the UE as seen from the RIS. Note that the direction of the UE as seen from the RIS corresponds to the direction of the UE starting from the RIS.

[0246] However, there is room for further study on how to identify the direction of the UE as seen from the RIS.

[0247] For example, since it is assumed that the RIS does not have a function of transmitting a signal from the RIS itself, it is difficult to identify the direction of the UE as seen from the RIS by a signal transmitted from the RIS using beam sweep, etc. If it is difficult to identify the direction of the UE as seen from the RIS, there is a possibility that the operation of transferring a signal to the direction of the UE as seen from the RIS cannot be performed.

[0248] In addition, since the UE is assumed to be mobile rather than fixed, the direction of the UE as seen from the RIS also changes as the UE moves, so it is desirable to determine the direction of the UE as seen from the RIS periodically or as needed.

[0249] Therefore, in this embodiment, a method for appropriately controlling relay operations in a RIS by identifying the UE direction as seen from the RIS will be described. Note that the following will show an example in which a RIS-MT, which has the ability (or function) to control the RIS and the ability (or function) to communicate with other wireless communication devices (e.g., UEs), identifies the UE direction as seen from the RIS, and an example in which a BS identifies the UE direction as seen from the RIS.

[0250] In the following description, the terms "identify," "determine," "select," and "estimate" may be used interchangeably.

[0251] Fig. 13 is a diagram showing an example of control in this embodiment. Fig. 13 shows a BS, a RIS-MT, a RIS, and a UE. Fig. 13 also shows three steps related to control.

[0252] As shown in Fig. 13, the control of the RIS in this embodiment is performed in three steps. Step 1: Identify the beam direction. Step 2: Determine the reflection direction at the RIS based on the identified beam direction. Step 3: Determine a RIS pair (for example, a pair of an incident angle and a reflection angle) based on the reflection direction at the RIS.

[0253] Here, the beam direction in step 1 refers to the direction of the beam formed by the RIS-MT toward the UE, and may correspond to the direction of the UE as seen from the RIS-MT. Furthermore, in step 2, the reflection direction at the RIS refers to the reflection direction when the RIS reflects a signal arriving at the RIS toward the UE, and may correspond to the direction of the UE as seen from the RIS. Furthermore, in the following description, the reflection direction may be replaced with the direction of the reflected beam. For example, control of the reflection direction may be considered as control of the direction of the reflected beam, or as control of the reflection angle. Furthermore, control of the reflection angle may be considered as control of the phase of the RIS so as to reflect at a set reflection angle.

[0254] Also, when steps 1 to 3 are performed by the RIS-MT, the RIS-MT may feed back information indicating the determined RIS pair to the BS.

[0255] An example of the processing executed in each step will be described below.

[0256] <Step 1: Identifying Beam Direction> To identify the beam direction (eg, the direction of the UE as seen from the RIS-MT), the RIS-MT performs beam detection (beam sweeping) to identify the direction of the UE as seen from the RIS-MT.

[0257] Since the RIS-MT is treated as equivalent to a UE, beam detection may be performed as beam selection in terminal-to-terminal communication (e.g., communication in sidelink). Alternatively, beam detection is performed as beam selection in the NR Uu.

[0258] Although the method of beam selection in sidelink or NR Uu is not specifically specified, for example, beam sweeping may be performed between the RIS-MT and the UE, similar to the beam sweeping between the TRP and the UE described above.

[0259] Fig. 14 is a diagram showing an example of a method of beam sweeping between a RIS-MT and a UE. Fig. 14 shows steps (1) to (3), which are beam sweeping steps between a RIS-MT and a UE, and step (4), which is the result of the three steps. Note that in Fig. 14, the RIS-MT forms a transmit beam and transmits a signal using the transmit beam, and the UE forms a receive beam and receives the signal using the receive beam. In Fig. 14, the transmit beam formed by the RIS-MT and the receive beam formed by the UE are shown in different ways.

[0260] In procedure (1), initial beam selection is performed by beam sweeping of a sidelink version of SSB (e.g., S-SSB (Sidelink Synchronization Signal Block)). For example, RIS-MT sweeps multiple S-SSBs in different beam directions. The UE receives the S-SSB, measures the reception quality (e.g., signal-to-noise power ratio (SNR)), etc.), and selects a beam based on the measurement results. In the initial beam selection, a coarse beam is selected. Note that the signal used in procedure (1) does not have to be limited to S-SSB.

[0261] For example, in step (1) of Fig. 14, the RIS-MT performs beam sweep using transmit beams #1 to #3. The UE performs beam sweep using receive beams #1 to #3. Note that transmit beams #1 to #3 and receive beams #1 to #3 are beams with relatively wide beam widths, corresponding to coarse beams.

[0262] In step (1) of Fig. 14, transmit beam #2 and receive beam #2 are selected, and the UE reports information indicating the selected beam (transmit beam #2 in the example of Fig. 14) to the RIS-MT.

[0263] In procedure (2), a second-stage transmission beam is selected by beam sweeping a reference signal (for example, at least one type of RS such as a CSI-RS). In the second-stage transmission beam selection, a transmission beam that is narrower than the transmission beam used in the initial beam selection is selected. For example, in the second-stage transmission beam selection, a transmission beam having a relatively narrow beam width is used, which corresponds to the transmission beam with a wide beam width selected in the initial beam selection. For example, RIS-MT sweeps the RS in different beam directions. The UE receives the RS, measures the reception quality (for example, the signal-to-noise power ratio (SNR)), and selects a beam based on the measurement results.

[0264] For example, in step (2) of Figure 14, the RIS-MT performs beam sweeping using transmit beams #2a, #2b, and #2c corresponding to transmit beam #2. Transmit beams #2a, #2b, and #2c corresponding to transmit beam #2 are one or more transmit beams directed in the direction of transmit beam #2 and its vicinity, and have a beam width narrower than the beam width of transmit beam #2. The UE receives a signal (e.g., RS) transmitted from the RIS-MT using the selected receive beam #2.

[0265] In step (2) of Fig. 14, transmission beam #2b is selected from transmission beams #2a, #2b, and #2c. The UE reports information indicating the selected beam (transmission beam #2b in the example of Fig. 14) to the TRP.

[0266] In step (3), a second-stage reception beam is selected by beam sweeping of the RS (e.g., CSI-RS). In the second-stage reception beam selection, a reception beam narrower than the reception beam used in the initial beam selection is selected. For example, in the second-stage reception beam selection, a reception beam having a relatively narrow beam width is used, corresponding to the reception beam selected in the initial beam selection having a wide beam width.

[0267] For example, in step (3) of Figure 14, the RIS-MT transmits a signal (e.g., RS) using transmit beam #2b. The UE performs beam sweeping using receive beams #2a, #2b, and #2c corresponding to receive beam #2. The receive beams #2a, #2b, and #2c corresponding to receive beam #2 are one or more receive beams directed in the direction of receive beam #2 and its vicinity, and have a beam width narrower than that of receive beam #2.

[0268] In step (3) of FIG. 14, reception beam #2b is selected from reception beams #2a, #2b, and #2c.

[0269] The RIS-MT transmits a signal using transmit beam #2b, and the UE receives the signal using receive beam #2b.

[0270] In step (3), the direction of the UE as seen from the RIS-MT is determined one-to-one. Even if a beam failure or the like occurs, beam recovery and beam selection operations may be performed in the same manner as in the procedure shown in FIG.

[0271] In the above-described procedure, the UE may report to the RIS-MT information indicating the selected beam as well as information indicating the reception quality of the received signal and information indicating the arrival time of the received signal (for example, the arrival time of the signal from the RIS-MT to the UE). The reception quality and the arrival time may be regarded as examples of information indicating the distance between the RIS-MT and the UE.

[0272] Note that, although FIG. 14 illustrates an example in which the RIS-MT transmits a signal (e.g., S-SSB, RS), the present disclosure is not limited thereto. For example, in beam sweeping, the RIS-MT may receive a signal. The assumption in which the RIS-MT transmits a signal may be referred to as a transmission assumption, and the assumption in which the RIS-MT receives a signal may be referred to as a reception assumption. For example, if the link between the RIS-MT and the UE is a sidelink, the correspondence between the RIS-MT and the UE may be opposite to that illustrated in the example of FIG. 14.

[0273] For example, if the correspondence relationship between the RIS-MT and the UE is opposite to that shown in Fig. 14, in procedure (1), the UE performs beam sweep using a transmission beam, and the RIS-MT performs beam sweep using a reception beam. In this case, the correspondence relationship between the RIS-MT and the UE is also opposite to that shown in Fig. 14 from procedure (2) onwards.

[0274] <Step 2: Determining the Reflection Direction> After the beam direction (eg, the direction of the UE as seen from the RIS-MT) is determined, the reflection direction at the RIS (eg, the direction of the UE as seen from the RIS) is determined.

[0275] A RIS-MT holds information about the positional relationship between the RIS connected to the RIS-MT and the RIS. The information about the positional relationship between the RIS and the RIS-MT includes information about at least one of the position of the RIS (for example, coordinates on a plane), the altitude of the RIS, the tilt angle of the RIS, and the rotation angle of the RIS. The tilt angle of the RIS and the rotation angle of the RIS may be considered as examples of information about the attitude of the RIS.

[0276] The RIS-MT determines the UE direction as seen from the RIS based on information regarding the positional relationship between the RIS and the RIS-MT and the UE direction as seen from the RIS-MT. For example, the coordinates of a UE assumed to be in the UE direction as seen from the RIS-MT are estimated, and the direction of the estimated UE coordinates as seen from the RIS is determined based on the positional relationship between the RIS and the RIS-MT. Note that information indicating the distance between the RIS-MT and the UE (e.g., reception quality, arrival time), etc. may be used to estimate the UE coordinates.

[0277] <Step 3: Determining the reflection angle> The RIS performs relaying (or forwarding) by reflecting a signal addressed to the UE that arrives (incident) at the RIS toward the direction of the UE as seen from the RIS. The direction of the UE as seen from the RIS corresponds to the reflection direction, and a reflection angle along this reflection direction is determined. One of the following three options is applied to determine the reflection angle of the RIS. Option 1: The RIS-MT controls the reflection angle of the RIS. Option 2: The BS controls the reflection angle of the RIS. Option 3: A combination of options 1 and 2. Note that controlling the RIS may include determining the reflection angle of the RIS and notifying (or instructing) the determined reflection angle.

[0278] In the case of Option 1, the BS does not need to control the RIS. In the case of Option 2, the BS determines the reflection angle of the RIS and transmits the determined reflection angle information to the RIS-MT, and the RIS-MT controls the reflection angle of the RIS based on the received reflection angle information.

[0279] As in the case of Option 1, the RIS-MT controls the RIS, so the RIS-MT may be considered an example of a control device that controls the RIS. In the case of Option 2, the BS determines the reflection angle of the RIS and transmits information about the determined reflection angle to the RIS-MT, thereby controlling the RIS, so the BS may be considered an example of a control device that controls the RIS.

[0280] In Option 1, if the RIS-MT cannot control the reflection angle in the RIS, in which the reflection direction is the UE direction as seen from the RIS, the RIS-MT may report to the BS that the reflection angle cannot be controlled in the RIS. A case in which the RIS cannot control the reflection angle in the RIS, in which the reflection direction is the UE direction as seen from the RIS, may be when the reflection angles supported by the RIS do not include a reflection angle in which the reflection direction is the UE direction as seen from the RIS. In this case, the BS may determine the RIS to use or the reflection angle at the RIS based on the report. The determination of the RIS to use or the reflection angle at the RIS at the BS will be described later.

[0281] Next, we will explain each of the three options mentioned above.

[0282] <Option 1 for Beam Control of RIS> In option 1, the RIS-MT determines the reflection angle at the RIS and controls the reflection angle (e.g., the direction of the reflected beam) at the RIS. In option 1, the BS does not need to control the reflection angle.

[0283] For example, RIS-MT identifies a pair of an incident angle and a reflection angle at the RIS (hereinafter, sometimes referred to as a RIS pair).

[0284] Pairs of incident angles and reflection angles may be stored in association with indexes. The correspondence between pairs of incident angles and reflection angles and indexes may be stored in table format. A table of correspondence between pairs of incident angles and reflection angles and indexes may be referred to as an incident / reflection angle table. The incident / reflection angle table may be held by the RIS-MT or the BS. The RIS-MT may have an incident / reflection angle table for a RIS connected to the RIS-MT, and the BS may have an incident / reflection angle table for each of one or more usable RISs.

[0285] 15 is a diagram showing an example of an incident / reflection angle table showing the correspondence relationship between the incident angle and the reflection angle at the RIS. In this correspondence relationship, for example, an incident angle of 30° is associated with reflection angles of 50°, 55°, and 60°. This correspondence relationship indicates that the RIS can reflect a radio wave (signal) incident on the RIS at an incident angle of 30° at a reflection angle of 50°, 55°, or 60°.

[0286] In addition, in Fig. 15, a link index is assigned to a pair of one incident angle and one reflection angle corresponding to the incident angle. The link index is an example of identification information that identifies a pair of an incident angle and a reflection angle. In addition, in Fig. 15, a reflection angle index is assigned to a reflection angle. The reflection angle index is an example of identification information that identifies a reflection angle. Note that these two types of indexes may be assigned, or at least one of them may be omitted.

[0287] When indexes are assigned to the reflection angles, the reflection angles may be divided into relatively large increments of 5°, and an index may be assigned to each reflection angle.

[0288] 15 is determined based on the capabilities (or characteristics) of the RIS. For example, the incident and reflection angle table may be regarded as an example of the capabilities of the RIS.

[0289] The RIS pair shown in FIG. 15 is used when selecting a reflection angle (or a possible reflection angle) from the link index.

[0290] The RIS-MT has an incident / reflection angle table such as that shown in FIG. 15 in advance, and determines a RIS pair (e.g., a reflection angle) by referring to the incident / reflection angle table. For example, as in steps 1 and 2 described above, the RIS-MT determines the UE direction as seen from the RIS based on the UE direction as seen from the RIS-MT and the positional relationship between the RIS and the RIS-MT. Then, in step 3, the RIS-MT selects a RIS pair from the incident / reflection angle table, whose reflection direction is the UE direction as seen from the RIS. The reflection angle whose reflection direction is the UE direction as seen from the RIS may be a reflection angle that reflects toward the UE direction as seen from the RIS, or a reflection angle that reflects in a direction closest to the UE direction as seen from the RIS.

[0291] For example, if the UE direction as seen from the RIS is determined to be a 50° direction, the RIS-MT having the incident / reflection angle table shown in Fig. 15 selects a reflection angle of 50°. Also, if the UE direction as seen from the RIS is determined to be a 52° direction, the RIS-MT having the incident / reflection angle table shown in Fig. 15 selects a reflection angle of 50° because this is the closest angle.

[0292] Here, if the reflection angle in which the UE direction as seen from the RIS is the reflection direction does not exist in the incident reflection angle table, the RIS-MT may report to the BS that the reflection angle does not exist. For example, if the UE direction as seen from the RIS is determined to be 30°, the RIS-MT having the incident reflection angle table shown in FIG. 15 reports to the BS that the corresponding reflection angle does not exist in the table. Note that this report may include information indicating the UE direction as seen from the RIS and / or information indicating the UE direction as seen from the RIS-MT. In this case, the BS may operate to communicate with the UE by relaying through another RIS different from the RIS connected to the RIS-MT that made the report.

[0293] As described above, if the reflection angle in which the UE direction as seen from the RIS is the reflection direction does not exist in the incident reflection angle table, the RIS-MT may report to the BS, and the BS may determine the RIS to be used or the reflection angle at the RIS. Note that the determination of the RIS to be used or the reflection angle at the RIS at the BS will be described later.

[0294] When notifying the determined reflection angle or RIS pair, for example, any of the following Alt.1 to Alt.3 may be applied: Alt.1: Notify the index of the reflection angle Alt.2: Notify the link index Alt.3: Notify the value of the reflection angle

[0295] The notification method when notifying based on any of the above-mentioned Alt.1 to Alt.3 is not particularly limited. For example, at least one of DCI, RRC, MAC CE, OAM, etc. may be used.

[0296] The RIS pair may be determined based on the incident angle, for example, the BS derives the incident angle based on the positional relationship between the BS antenna and the RIS.

[0297] For example, the positional relationship between the BS antenna and the RIS is obtained from information about the three-dimensional position of the BS antenna and information about the three-dimensional position of the RIS. The BS may then derive the incident angle from the geometric positional relationship between the BS antenna and the RIS in three-dimensional space based on the information about the three-dimensional position of the BS antenna and the information about the three-dimensional position of the RIS. For example, a straight line may be defined that connects a representative point of the BS antenna in three-dimensional space (e.g., the center of the antenna) and a representative point of the reflecting surface of the RIS (e.g., the center of the reflecting surface), and the angle formed by the defined straight line and a perpendicular line extending perpendicularly from the representative point of the reflecting surface of the RIS may be the incident angle.

[0298] The information regarding the three-dimensional position of the BS antenna includes at least one of the following: the position information of the BS in a two-dimensional plane (e.g., latitude and longitude), the altitude of the BS antenna, the tilt angle of the BS antenna, and the rotation angle.

[0299] The information regarding the three-dimensional position of the RIS includes at least one of the position information of the RIS on a two-dimensional plane (e.g., the latitude and longitude of the RIS position), the altitude of the RIS, and the angle of the RIS (the orientation of the RIS).

[0300] Here, the BS may store information about the three-dimensional position of the BS antenna, while the BS may acquire information about the three-dimensional position of the RIS from the RIS, from an external device other than the RIS, or store the information in advance.

[0301] The BS reports the derived incident angle to the RIS-MT, and the RIS-MT selects a pair of the reported incident angle and the reflection angle corresponding to the determined reflection direction from an incident-reflection angle table.

[0302] Alternatively, the RIS-MT may derive the angle of incidence. For example, the RIS-MT derives the angle of incidence based on the positional relationship between the BS antenna and the RIS (e.g., the reflecting surface of the RIS). The angle of incidence may also be determined based on the direction of the beam selected as a result of a beam sweep performed between the RIS-MT and the BS.

[0303] For example, the RIS-MT transmits information about the determined reflection angle (or the direction of the UE as seen from the RIS, or the direction of the UE as seen from the RIS-MT) to the BS when communication between the BS and the UE is possible and / or when communication between the BS and the UE is not possible. The case where communication between the BS and the UE is possible may correspond to, for example, when the RIS-MT is able to determine the reflection angle, and the case where communication between the BS and the UE is not possible may correspond to, for example, when the RIS-MT is not able to determine the reflection angle (for example, when the corresponding reflection angle is not included in the incident reflection angle table).

[0304] In addition, when reflection angles corresponding to reflection directions toward a specific UE are obtained from multiple RISs, the coordinates of the specific UE may be determined based on the obtained reflection angles. Then, based on the determined UE coordinates, an appropriate RIS may be selected from the multiple RISs. Note that the determination of the UE coordinates will be described later.

[0305] Through the above-described processing, the RIS-MT determines the reflection angle at the RIS and controls the reflection angle at the RIS (for example, the direction of the reflected beam).

[0306] As shown in Option 1, the RIS-MT determines the reflection angle of the RIS and controls the reflection angle at the RIS, thereby enabling appropriate control of the RIS. For example, the RIS-MT performs a beam sweep to determine the UE direction as seen from the RIS-MT, and then determines the UE direction as seen from the RIS (e.g., the reflection direction). This allows for more appropriate control of the RIS, since the UE direction as seen from the RIS can be determined even if the RIS cannot perform a beam sweep between the RIS and the UE. Furthermore, because control can be performed between the RIS-MT, the RIS, and the UE, the time required to control the RIS can be reduced.

[0307] <Option 2 for Beam Control of RIS> In option 2, the BS determines the reflection angle of the RIS and controls the reflection angle at the RIS. In option 2, the RIS-MT notifies the BS of information for controlling the reflection angle.

[0308] For example, the BS may acquire from the RIS-MT information indicating the direction of the UE as seen from the RIS, or information indicating the direction of the UE as seen from the RIS-MT, and determine the reflection angle of the RIS based on the acquired information. Note that the BS may acquire location information such as coordinates of the RIS-MT (or RIS) from the RIS-MT, or may have location information such as coordinates of the RIS-MT (or RIS) in advance. Note that the method by which the BS determines the reflection angle of the RIS may be the same as the above-mentioned method by which the RIS-MT determines the reflection angle of the RIS. For example, the BS may have a RIS incident reflection angle table, and may select from the incident reflection angle table a reflection angle whose reflection direction is the UE direction as seen from the RIS.

[0309] In addition, the BS may obtain information indicating the direction of the UE as seen from the RIS, or information indicating the direction of the UE as seen from the RIS-MT, from each of the multiple RIS-MTs, and determine the reflection angle of the RIS based on the obtained information.

[0310] The BS may select a RIS to use for communication with the UE based on the correspondence between the link index and the notified reflection angle, or may select a path consisting of multiple RISs when communicating with the UE via two or more RISs. This selection may be made periodically, for example, every time a report on the reflection angle is sent.

[0311] For example, in option 2, the BS identifies location information of the UE (e.g., coordinates of the UE) and controls the RIS based on the identified location information of the UE. For example, the BS determines the RIS to be used when transmitting a signal from the BS to the UE based on the location information of the UE, and controls the reflection angle (e.g., direction of the reflected beam) at the determined RIS.

[0312] When the BS obtains information about the UE direction as seen from the RIS-MT from multiple RIS-MTs, the BS retains information about the UE direction as seen from each of the multiple RIS-MTs. Because there are multiple UE directions as seen from the RIS-MTs, the UE coordinates are estimated using at least a portion of the coordinates of the RIS-MT (or RIS) and the UE directions as seen from each of the multiple RIS-MTs (or RISs). Two options for UE coordinate estimation are described below. The BS estimates the UE coordinates based on one of the two options.

[0313] <UE Coordinate Estimation Option 1> When a UE receives a signal transmitted by a RIS-MT, the UE may measure the arrival time of the received signal. Here, the measured arrival time corresponds to the distance between the RIS-MT and the UE. Also, when a UE receives a signal transmitted (or transmitted) by a RIS, the UE may measure the arrival time of the received signal. Here, the measured arrival time corresponds to the distance between the RIS and the UE.

[0314] The UE side initiates the estimation of the UE's coordinates based on the time of arrival (ToA (Time of Arrival)). For example, the time of arrival may be the arrival time of a signal (e.g., S-SSB or RS) transmitted from a RIS-MT and received by the UE, or may be the arrival time of a signal (e.g., S-SSB or RS) transmitted from a BS and received by the UE. When the UE side initiates the estimation of the UE's coordinates, the UE may acquire location information such as the coordinates of the RIS-MT from each RIS-MT.

[0315] The BS may estimate the coordinates of the UE based on the arrival time. In this case, the UE reports the arrival time of the signal transmitted from each RIS-MT to each RIS-MT. The arrival time may be reported to the RIS-MT, for example, when the UE reports the beam selected in step 1 above. The RIS-MT reports the arrival time reported from the UE to the BS. The arrival time may be reported to the BS when the RIS-MT reports the UE direction as seen from the RIS (or the UE report as seen from the RIS-MT) to the BS.

[0316] When distinguishing between multiple RIS-MTs, the multiple RIS-MTs are written as RIS-MT#1, RIS-MT#2, etc.

[0317] The coordinates of the UE are estimated based on the coordinates of the RIS-MT, the direction of the UE as seen from the RIS-MT, and the arrival time of a signal transmitted from the RIS-MT and received by the UE. Note that the coordinates of the UE may also be estimated based on the coordinates of the RIS, the direction of the UE as seen from the RIS, and the arrival time of a signal transmitted from the RIS and received by the UE.

[0318] Fig. 16 is a diagram showing an example of option 1 for UE coordinate estimation. Fig. 16 shows the coordinates of RIS#i (i is 1, 2, or 3), UE direction#i indicating the UE direction as seen from RIS#i, and TOA#i, which is the time of arrival corresponding to the distance between RIS#i and the UE. UE direction#i in Fig. 16 is defined as an angle relative to a reference plane (or line). Note that UE direction may be replaced with other expressions such as beam direction or beam sending angle.

[0319] Note that the coordinates of RIS#i may be replaced with the coordinates of RIS-MT#i. Furthermore, UE direction#i may be the UE direction as seen from RIS-MT#i, instead of the UE direction as seen from RIS#i. Furthermore, TOA#i may be the time of arrival of a signal transmitted (or forwarded) by RIS#i and received by the UE. Alternatively, TOA#i may be the time of arrival of a signal transmitted (or forwarded) by RIS-MT#i and received by the UE.

[0320] As shown in Figure 16, for example, the coordinates of the UE are estimated based on the coordinates of RIS-MT#1, the direction of the UE as seen from RIS-MT#1, and the arrival time of the signal transmitted from RIS-MT#1 and received by the UE.

[0321] Furthermore, the coordinates of the UE are estimated based on the coordinates of each of the multiple RIS-MTs, the direction of the UE as seen from each of the multiple RIS-MTs, and the arrival time of the signal transmitted from each of the multiple RIS-MTs and received by the UE. For example, in the case of two RIS-MTs, the coordinates of the UE are estimated based on the coordinates of RIS-MT#1, the direction of the UE as seen from RIS-MT#1, the arrival time of the signal transmitted from RIS-MT#1 and received by the UE, the coordinates of RIS-MT#2, the direction of the UE as seen from RIS-MT#2, and the arrival time of the signal transmitted from RIS-MT#2 and received by the UE.

[0322] In option 1, the arrival time of the signal may be replaced with the reception quality of the signal (for example, SNR or RSSI (Received Signal Strength Indicator)).

[0323] <UE Coordinate Estimation Option 2> Since there are two or more UE directions as seen from the RIS-MT, the UE coordinates are determined based on the two or more UE directions. For example, the coordinates of the intersection of the two or more UE directions are determined to be the UE coordinates.

[0324] Fig. 17 is a diagram showing an example of UE coordinate estimation option 2. Fig. 17 shows the coordinates of RIS#i (i is 1, 2, or 3) and UE direction #i, which indicates the direction of the UE as seen from RIS#i.

[0325] The coordinates of RIS#i may be replaced with the coordinates of RIS-MT#i. Furthermore, the UE direction#i may be the UE direction as seen from RIS-MT#i, instead of the UE direction as seen from RIS#i.

[0326] 17 is defined as an angle relative to a reference plane (or line). Note that the UE direction may be expressed as a beam direction, a beam sending angle, or the like.

[0327] As shown in FIG. 17, the intersection of UE direction #1, UE direction #2, and UE direction #3 is determined to be the coordinates of the UE.

[0328] Although FIG. 17 shows an example in which the coordinates of a UE are determined from three UE directions, they may be determined from two UE directions.

[0329] Next, the processing flow of each of the BS, RIS, RIS-MT, and UE in option 2, in which the BS determines the reflection angle of the RIS and controls the reflection angle at the RIS, will be described. Note that the following description shows an example in which the BS determines the UE coordinates based on option 2 of UE coordinate estimation.

[0330] Fig. 18 is a sequence diagram showing the processing flow of Option 2 of RIS beam control in this embodiment. Fig. 18 shows, as an example, an example in which the BS determines UE coordinates based on information acquired from RIS-MT#1 and RIS-MT#2, and controls the RIS based on the determined UE coordinates.

[0331] RIS-MT#1 performs beam sweeping between RIS-MT#1 and the UE (S101). Then, RIS-MT#1 identifies the direction of the UE based on the results of the beam sweep (S102). RIS-MT#1 transmits information indicating the identified direction of the UE to the BS (S103).

[0332] The RIS-MT#2 performs beam sweeping between the RIS-MT#2 and the UE (S104). Then, the RIS-MT#2 identifies the direction of the UE based on the results of the beam sweep (S105). The RIS-MT#2 transmits information indicating the identified direction of the UE to the BS (S106).

[0333] Note that the order of S101 to S103 and S104 to S106 is not limited to that shown in Fig. 18. For example, the processes of S104 to S106 may be performed before S103.

[0334] The BS determines the UE coordinates based on the respective coordinates of RIS-MT#1 and RIS-MT#2 and the acquired UE direction (S107).

[0335] Based on the determined UE coordinates, the BS selects the RIS to be used when transmitting a signal to the UE from RIS#1 and RIS#2 (S108). Figure 17 shows an example in which RIS#1 is selected. Then, the BS determines the reflection angle to be used for the selected RIS#1 (S109).

[0336] For example, the BS determines the UE direction (i.e., reflection direction) for each selectable RIS as seen from the RIS based on information about the location of each selectable RIS (RIS#1 and RIS#2 in the example of FIG. 18) and the estimated UE coordinates.The BS then references the incident reflection angle table for each selectable RIS, selects a RIS that can use a reflection angle corresponding to the determined reflection direction as the RIS to be used when transmitting a signal to the UE, and determines the reflection angle to be used for the selected RIS.Note that if there are multiple RISs that can use a reflection angle corresponding to the determined reflection direction, information such as the distance between the BS and the RIS, the distance between the RIS and the UE, and the quality of the route from the BS to the UE may be used to select the RIS.

[0337] The BS acquires information about the position of each of the selectable RISs (for example, coordinates of the RIS) and information about the incident / reflection angle table of each of the selectable RISs from each RIS-MT.

[0338] The BS transmits control information for the RIS#1, including information indicating the determined reflection angle, to the RIS-MT#1 that controls the selected RIS#1 (S110).

[0339] RIS-MT#1 controls the forwarding operation (e.g., reflection operation, etc.) of RIS#1 by transmitting control information of RIS#1 based on the received control information to RIS#1 (S111). For example, the forwarding operation (e.g., reflection operation, etc.) is controlled by controlling the phase of RIS#1 (e.g., the phase of each of multiple antenna elements).

[0340] The BS transmits a signal addressed to the UE (S112), where the transmitted signal is forwarded (e.g., reflected) by the RIS#1 and received by the UE (S113).

[0341] Note that, although the sequence diagram shown in FIG. 18 illustrates an example in which the BS selects a RIS and determines the reflection angle at the selected RIS, the present disclosure is not limited to this. For example, the BS may select a RIS and notify the RIS-MT controlling the selected RIS that the RIS will be used for communication with the UE. In this case, the RIS-MT that receives the notification may determine the reflection angle to be used at the RIS. Note that the notification from the BS in this case may include the coordinates of the UE. The RIS-MT may then determine the reflection angle at the RIS based on the coordinates of the UE included in the notification.

[0342] As shown in Option 2, the BS determines the reflection angle of the RIS and controls the reflection angle at the RIS, thereby enabling appropriate control of the RIS. For example, as described above, the BS identifies the UE coordinates based on information from multiple RIS-MTs and determines the reflection angle of the RIS, so that the reflection angle for the exact position of the UE can be determined, enabling more appropriate control of the RIS. Furthermore, in Option 2, a RIS suitable for relaying can be selected from multiple RISs, enabling more appropriate control of the RIS.

[0343] <RIS Beam Control Option 3> In RIS beam control option 3, control is performed by combining RIS beam control options 1 and 2.

[0344] For example, Option 2 may be used when Option 1 cannot be used. For example, when the RIS-MT determines the angle of reflection at the RIS and cannot control the angle of reflection at the RIS as shown in Option 1, the RIS-MT may determine the angle of reflection at the RIS and control the angle of reflection at the RIS as shown in Option 2.

[0345] Here, a case in which option 1 cannot be used may be, for example, when the incident reflection angle table held by the RIS-MT does not include a reflection angle corresponding to the reflection direction determined by the RIS-MT.

[0346] Also, for example, option 1 and option 2 may be selected depending on requirements for communication between the BS and the UE. For example, if a relatively high communication speed between the BS and the UE or real-time communication is required, option 1 may be selected in which the RIS-MT controls the RIS without going through the BS. On the other hand, if a relatively low communication speed between the BS and the UE is acceptable but high quality is required, option 2 may be selected in which the BS determines the UE coordinates and controls the RIS.

[0347] Also, for example, Option 1 and Option 2 may be selected depending on the type of RIS or RIS-MT. For example, when issuing instructions to RIS-MT#1 that does not support beam sweep processing, the BS may obtain the UE direction from another RIS-MT (e.g., RIS-MT#2) that supports beam sweep processing, and may determine the reflection angle of the RIS controlled by RIS-MT#1 based on the obtained UE direction.

[0348] In the above-described embodiment, the destination of a forwarding operation performed by a RIS is not limited to a UE. For example, the RIS may forward a signal to a BS or to another RIS. In this case, the RIS-MT may determine the direction from the RIS (or RIS-MT) to the destination, and may determine the reflection angle at the RIS based on the determined direction.

[0349] In the present disclosure, "A / B" and "at least one of A and B" may be interpreted interchangeably. Also, in the present disclosure, "A / B / C" may mean "at least one of A, B, and C."

[0350] In the present disclosure, terms such as notify, activate, deactivate, indicate (or indicate), select, configure, update, and determine may be read interchangeably. In the present disclosure, terms such as support, control, controllable, operate, and operate may be read interchangeably.

[0351] In the present disclosure, Radio Resource Control (RRC), RRC parameters, RRC messages, higher layer parameters, fields, information elements (IEs), settings, etc. may be interchangeable. In the present disclosure, Medium Access Control (MAC) control elements (CEs), update commands, activation / deactivation commands, etc. may be interchangeable.

[0352] In the present disclosure, the higher layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, other messages (e.g., messages from the core network such as positioning protocol (e.g., NR Positioning Protocol A (NRPPa) / LTE Positioning Protocol (LPP)) messages), or a combination thereof.

[0353] In the present disclosure, MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. Broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0354] In the present disclosure, physical layer signaling may be, for example, Downlink Control Information (DCI), Uplink Control Information (UCI), and the like.

[0355] In this disclosure, terms such as aperture, antenna array, array, subarray (multiple antenna elements, part of an array), panel, RIS, RIS array, scattering element array, etc. may be interchangeable. In this disclosure, terms such as antenna, antenna element, scattering element, etc. may be interchangeable.

[0356] In the present disclosure, NCR, RIS, NCR including RIS, network node, device, IAB, IAB-MT (Mobile Termination), IAB-DU (Distribution Unit), IAB-CU (Central Unit), terminal, base station, relay station, relay device, repeater, reflector, transmittance plate, RIS-NCR, RIS type NCR, extended NCR, etc. may be read interchangeably.

[0357] <Block Configuration Diagram> Fig. 19 is a block diagram showing an example of the configuration of a base station 100 according to an embodiment of the present disclosure. The base station 100 includes, for example, a transmitting unit 101, a receiving unit 102, and a control unit 103. The base station 100 communicates wirelessly with a terminal 200 (see Fig. 20). The transmitting unit 101 and the receiving unit 102 may be collectively referred to as a communication unit. The control unit may also be referred to as a processing unit, a processor, or the like.

[0358] The transmitter 101 transmits a DL signal to the terminal 200. For example, the transmitter 101 transmits the DL signal under the control of the controller 103. For example, the DL signal may include information indicating scheduling related to signal transmission by the terminal 200 (for example, an UL grant), control information of higher layers, and the like.

[0359] For example, the transmitter 101 transmits, as DL signals, various control signals (such as control signals for higher layers), reference signals, data signals, etc. to the terminal 200 and / or the radio device 300. The transmitter 101 transmits, as DL signals, various signals, channels, setting information, control information, etc., described in the above embodiments, to the terminal 200.

[0360] For example, transmitting unit 101 transmits information related to the control of terminal 200, which is generated by control unit 103, to terminal 200. Also, for example, transmitting unit 101 transmits information related to the control of wireless device 300, which is generated by control unit 103, to wireless device 300. Also, transmitting unit 101 transmits a data signal generated by control unit 103 to terminal 200.

[0361] The receiving unit 102 receives the UL signal transmitted from the terminal 200. For example, the receiving unit 102 receives the UL signal under the control of the control unit 103. The receiving unit 102 may also receive the UL signal transmitted from the wireless device 300.

[0362] For example, the receiving unit 102 receives, as UL signals, signals including terminal capability information (e.g., UE capability) of the terminal 200, various control signals, reference signals, data signals, etc. from the terminal 200. The receiving unit 102 may also receive signals including capability information (e.g., capability) of the wireless device 300.

[0363] The control unit 103 controls the overall (communication) operation of the base station 100 , including the transmission processing in the transmission unit 101 and the reception processing in the reception unit 102 .

[0364] For example, the control unit 103 acquires information such as data and control information from the upper layer and outputs it to the transmitting unit 101. The control unit 103 also outputs the data, control information, etc. received from the receiving unit 102 to the upper layer.

[0365] For example, the control unit 103 allocates resources to be used for transmitting and receiving DL signals and / or resources to be used for transmitting and receiving UL signals based on signals (e.g., data and control information, etc.) received from the terminal 200 and / or data and control information, etc. acquired from a higher layer. Information on the allocated resources may be included in control information to be transmitted to the terminal 200.

[0366] The control unit 103 performs operations other than the transmission and reception described in the above embodiment (note that these operations may be performed by the transmission unit 101 and / or the reception unit 102).

[0367] Furthermore, the control unit 103 may generate control information related to the forwarding operation of the wireless device 300. The control unit 103 may transmit instructions (e.g., control information) related to communication control of the wireless device 300 via the transmission unit 101.

[0368] For example, the control unit 103 determines control information for controlling relaying in the antenna unit 304 based on a first direction from the antenna unit 304 (see FIG. 21 , an example of an antenna device) that relays a signal transmitted to the terminal 200 (an example of a wireless communication device) to the terminal 200. In this case, the transmitting unit 101 transmits the control information to the wireless device 300 (see FIG. 21 ) that includes the antenna unit 304. The first direction corresponds, for example, to the direction of the UE as seen from the above-mentioned RIS. Furthermore, the control information corresponds, for example, to the reflection angle at the above-mentioned RIS.

[0369] 20 is a block diagram showing an example of a configuration of a terminal 200 according to an embodiment of the present disclosure. The terminal 200 includes, for example, a receiving unit 201, a transmitting unit 202, and a control unit 203. The terminal 200 communicates with, for example, a base station 100 (see FIG. 19 ) wirelessly. Note that the receiving unit 201 and the transmitting unit 202 may be collectively referred to as a communication unit.

[0370] The receiving unit 201 receives a DL signal transmitted from the base station 100. For example, the receiving unit 201 receives the DL signal under the control of the control unit 203.

[0371] For example, the receiving unit 201 receives, as DL signals, various control signals, reference signals, data signals, etc. from the base station 100. For example, the receiving unit 201 receives, as DL signals, various signals, channels, setting information, control information, etc. described in the above embodiments from the base station 100.

[0372] For example, the receiving unit 201 receives a signal from the base station 100 .

[0373] The transmitting unit 202 transmits the UL signal to the base station 100. For example, the transmitting unit 202 transmits the UL signal under the control of the control unit 203.

[0374] For example, the transmitter 202 transmits, as UL signals, signals including information about the processing capacity of the terminal 200, various control signals, reference signals, data signals, and the like to the base station 100.

[0375] The control unit 203 controls the overall (communication) operation of the terminal 200 , including the reception processing in the reception unit 201 and the transmission processing in the transmission unit 202 .

[0376] For example, the control unit 203 acquires information such as data and control information from the upper layer and outputs it to the transmitting unit 202. Also, the control unit 203 outputs, for example, the data and control information received from the receiving unit 201 to the upper layer.

[0377] The control unit 203 performs operations other than the transmission and reception described in the above embodiment (note that these operations may be performed by the receiving unit 201 and / or the transmitting unit 202).

[0378] Note that the signal that terminal 200 receives from base station 100 may be a signal that has been transmitted directly from base station 100, or may be a signal that has been transmitted from base station 100 and transferred by radio device 300. Furthermore, the signal that terminal 200 transmits to base station 100 may be received directly by base station 100, or may be transferred by radio device 300 and then received by base station 100. In this case, terminal 200 does not need to recognize whether the signal has been transferred by radio device 300 or not.

[0379] FIG. 21 is a block diagram showing an example of a configuration of a wireless device 300 according to an embodiment of the present disclosure. The wireless device 300 corresponds to an example of a RIS and a RIS-MT. The wireless device 300 includes, for example, a control device 300a including a receiving unit 301, a transmitting unit 302, and a control unit 303, and an antenna unit 304. The control device 300a corresponds to a RIS-MT, and the antenna unit 304 corresponds to an antenna panel, an antenna device, or a RIS. The wireless device 300 wirelessly communicates with, for example, a base station 100 (see FIG. 19) and a terminal 200 (see FIG. 20). The receiving unit 301 and the transmitting unit 302 may be collectively referred to as a communication unit.

[0380] The receiving unit 301 receives a signal transmitted from the base station 100. The receiving unit 301 also receives a signal transmitted from the terminal 200. For example, the receiving unit 301 receives a signal under the control of the control unit 303. Note that the received signal may include a signal addressed to the control device 300a.

[0381] The transmitting unit 302 transmits a signal addressed to the base station 100 to the base station 100. The transmitting unit 302 also transmits a signal addressed to the terminal 200 to the terminal 200. For example, the transmitting unit 302 transmits the signal under the control of the control unit 303. The transmitting unit 302 may also transmit (or output) control information for controlling the antenna unit 304 to the antenna unit 304.

[0382] The antenna unit 304 performs a signal transfer (or relay) process based on the control of the control unit 303. The transfer process may include at least one of a process of transferring a signal addressed to the terminal 200 that has arrived from the base station 100 to the terminal 200, and a process of transferring a signal addressed to the base station 100 that has arrived from the terminal 200 to the terminal 200.

[0383] The control unit 303 controls the overall (communication) operation of the wireless device 300 , including the reception processing in the reception unit 301 , the transmission processing in the transmission unit 302 , and the transfer processing in the antenna unit 304 .

[0384] For example, the control unit 303 determines control information for controlling relaying in the antenna unit 304 based on a first direction from the antenna unit 304 (an example of an antenna device) that relays a signal transmitted to the terminal 200 (an example of a wireless communication device) toward the terminal 200. The first direction corresponds, for example, to the direction of the UE as seen from the above-mentioned RIS. Furthermore, the control information corresponds, for example, to the reflection angle at the above-mentioned RIS. In this case, the transmission unit 302 may transmit the control information to the antenna unit 304.

[0385] The control unit 303 performs operations other than the transmission and reception described in the above embodiment (note that these operations may be performed by the receiving unit 301 and / or the transmitting unit 302).

[0386] Note that the wireless device 300 in the present disclosure may be an example of a communication device. Furthermore, the wireless device 300 in the present disclosure may be referred to by other names such as a relay device, a forwarding device, or a relay device. Furthermore, the wireless device 300 in the present disclosure may be replaced with a terminal 200 (e.g., a UE). For example, the wireless device 300 may be considered as a terminal 200 having a forwarding function (or a relay function).

[0387] The present disclosure has been described above. Note that the division of items in the above description is not essential to the present disclosure, and items described in two or more items may be used in combination as needed, and items described in one item may be applied to items described in another item (unless they are inconsistent).

[0388] <Hardware Configuration, etc.> The block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (e.g., using wires, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining software with the single device or the multiple devices.

[0389] Functions include, but are not limited to, judgment, determination, assessment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0390] For example, a base station, a terminal, a wireless device, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 22 is a diagram illustrating an example of the hardware configuration of a base station, a terminal, and a wireless device according to an embodiment of the present disclosure. The base station 100, the terminal 200, and the wireless device 300 described above may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0391] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configurations of the base station 100, the terminal 200, and the wireless device 300 may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0392] Each function in the base station 100, the terminal 200, and the wireless device 300 is realized by loading predetermined software (programs) onto hardware such as the processor 1001 and the memory 1002, causing the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0393] The processor 1001 controls the entire computer by running, for example, an operating system. The processor 1001 may be configured by a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, the above-mentioned control unit 103, control unit 203, and control unit 303 may be realized by the processor 1001.

[0394] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002 and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 203 of the terminal 200 may be implemented by a control program stored in the memory 1002 and running on the processor 1001, and similar implementations may be made for other functional blocks. While the above-described various processes have been described as being executed by one processor 1001, they may also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may also be transmitted from a network via a telecommunications line.

[0395] The memory 1002 is a computer-readable recording medium and may be configured by, for example, at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), etc. The memory 1002 may also be called a register, a cache, a main memory (primary storage device), etc. The memory 1002 can store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to an embodiment of the present disclosure.

[0396] Storage 1003 is a computer-readable recording medium, and may be composed of, for example, at least one of an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray (registered trademark) disk), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, etc. Storage 1003 may also be referred to as an auxiliary storage device. The above-mentioned storage medium may be, for example, a database, a server, or other appropriate medium including at least one of memory 1002 and storage 1003.

[0397] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the above-mentioned transmitter 101, receiver 102, receiver 201, transmitter 202, receiver 301, transmitter 302, etc. may be realized by the communication device 1004.

[0398] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0399] Furthermore, each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0400] Furthermore, base station 100, terminal 200, and wireless device 300 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, processor 1001 may be implemented using at least one of these pieces of hardware.

[0401] <Notification of Information, Signaling> Notification of information is not limited to the embodiments described in the present disclosure and may be performed using other methods. For example, notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB))), other signals, or a combination thereof. Furthermore, RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0402] <Applicable Systems> The embodiments described in the present disclosure are applicable to LTE (Long Term Evolution), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (x is, for example, an integer or a decimal)), FRA (Future Radio Access), NR (new Radio), New radio access (NX), Future generation radio access (FX), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.17 (WiMAX (registered trademark)), IEEE 802.19 (WiMAX (registered trademark)), IEEE 802.20 (WiMAX (registered trademark)), IEEE 802.21 (Wi-Fi (registered trademark)), IEEE 802.22 (WiMAX (registered trademark)), IEEE 802.23 (WiMAX (registered trademark)), IEEE 802.24 (WiMAX (registered trademark)), IEEE 802.25 (WiMAX (registered trademark)), IEEE 802.26 (WiMAX (registered trademark)), IEEE 802.27 (WiMAX (registered trademark)), IEEE 802.28 (WiMAX (registered trademark)), IEEE 802.29 (WiMAX (registered trademark)), IEEE 802.30 (WiMAX (registered trademark)), IEEE 802.31 (Wi-Fi (registered trademark)), IEEE 802.32 (WiMAX (registered trademark)), IEEE 802.33 (WiMAX (registered trademark)), IEEE 802.34 (WiMAX (registered trademark The present invention may be applied to at least one of systems using 802.20, UWB (Ultra-Wide Band), Bluetooth (registered trademark), or other suitable systems, and next-generation systems that are extended, modified, created, or defined based on these systems. The present invention may also be applied to a combination of multiple systems (e.g., a combination of LTE and / or LTE-A with 5G).

[0403] <Processing Procedures, etc.> The processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be rearranged unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0404] <Operation of Base Station> In the present disclosure, specific operations described as being performed by a base station may also be performed by its upper node in some cases. In a network consisting of one or more network nodes having a base station, it is clear that various operations performed for communication with a terminal may be performed by at least one of the base station and another network node other than the base station (for example, an MME or an S-GW, etc., but are not limited to these). Although the above example illustrates a case where there is one other network node other than the base station, a combination of multiple other network nodes (for example, an MME and an S-GW) may also be used.

[0405] <Direction of Input / Output> Information, etc. (see <Information, Signal>) can be output from a higher layer (or a lower layer) to a lower layer (or a higher layer). It may also be input / output via multiple network nodes.

[0406] <Handling of Input / Output Information, etc.> Input / output information, etc. may be stored in a specific location (for example, memory) or may be managed using a management table. Input / output information, etc. may be overwritten, updated, or added. Output information, etc. may be deleted. Input information, etc. may be sent to another device.

[0407] <Determination method> The determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0408] <Variations of Aspects, etc.> Each aspect / embodiment described in the present disclosure may be used alone, in combination, or switched depending on the implementation. In addition, notification of predetermined information (e.g., notification that "X is true") is not limited to being done explicitly, but may be done implicitly (e.g., by not notifying the predetermined information).

[0409] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure.

[0410] <Software> Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0411] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0412] Information, Signals, etc., described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc., which may be referred to throughout the above description, may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0413] Note that terms described in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

[0414] <System, Network> As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0415] <Parameter and Channel Names> Furthermore, the information, parameters, and the like described in the present disclosure may be expressed using absolute values, relative values ​​from a predetermined value, or other corresponding information. For example, a radio resource may be indicated by an index.

[0416] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0417] <Base Station> In the present disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably. A base station may also be referred to by terms such as a macrocell, a small cell, a femtocell, and a picocell.

[0418] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the entire coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can provide communication services by a base station subsystem (e.g., a small indoor base station (RRH: Remote Radio Head)). The term "cell" or "sector" refers to a part or the entire coverage area of ​​at least one of the base station and base station subsystem that provides communication services in this coverage. In the present disclosure, the base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control and operate based on the information.

[0419] Mobile Station In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," and the like may be used interchangeably.

[0420] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0421] <Base Station / Mobile Station> At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile object, the mobile object itself, etc. The mobile object refers to a movable object, and may move at any speed. Naturally, this also includes cases where the mobile object is stationary. Examples of the mobile object include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones (registered trademark), multicopters, quadcopters, balloons, and objects mounted thereon. The mobile object may also be an autonomous mobile object operating based on an operational command. It may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may be a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0422] Furthermore, a base station in the present disclosure may be read as a terminal. For example, the embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a terminal is replaced with communication between multiple terminals (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the functions of the base station 100 described above may be configured to be possessed by the terminal 200 and the wireless device 300. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0423] Similarly, the term "terminal" in the present disclosure may be interpreted as a base station, in which case the base station 100 and the relay station 300 may be configured to have the functions of the terminal 20 described above.

[0424] Fig. 23 shows an example configuration of a vehicle 2001. As shown in Fig. 23, the vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013. Each aspect / embodiment described in the present disclosure may be applied to a communication device mounted on the vehicle 2001, and may be applied to the communication module 2013, for example.

[0425] The drive unit 2002 is configured, for example, by an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel operated by the user.

[0426] The electronic control unit 2010 is composed of a microprocessor 2031, a memory (ROM, RAM) 2032, and a communication port (IO port) 2033. Signals are input to the electronic control unit 2010 from various sensors 2021 to 2029 provided in the vehicle 2001. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0427] The signals from the various sensors 2021 to 2029 include a current signal from a current sensor 2021 that senses the current of the motor, a rotation speed signal of the front and rear wheels obtained by a rotation speed sensor 2022, an air pressure signal of the front and rear wheels obtained by an air pressure sensor 2023, a vehicle speed signal obtained by a vehicle speed sensor 2024, an acceleration signal obtained by an acceleration sensor 2025, an accelerator pedal depression amount signal obtained by an accelerator pedal sensor 2029, a brake pedal depression amount signal obtained by a brake pedal sensor 2026, a shift lever operation signal obtained by a shift lever sensor 2027, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 2028.

[0428] The information service unit 2012 is composed of various devices, such as a car navigation system, an audio system, speakers, a television, and a radio, for providing (outputting) various types of information, such as driving information, traffic information, and entertainment information, and one or more ECUs that control these devices. The information service unit 2012 provides various types of multimedia information and multimedia services to the occupants of the vehicle 2001 by using information acquired from external devices via the communication module 2013, etc.

[0429] The information service unit 2012 may include input devices (e.g., keyboards, mice, microphones, switches, buttons, sensors, touch panels, etc.) that accept input from the outside, and may also include output devices (e.g., displays, speakers, LED lamps, touch panels, etc.) that output to the outside.

[0430] The driving assistance system unit 2030 is composed of various devices that provide functions for preventing accidents and reducing the driving burden on the driver, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS, etc.), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System), etc.), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. In addition, the driving assistance system unit 2030 transmits and receives various information via the communication module 2013 to realize the driving assistance function or the autonomous driving function.

[0431] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via the communication port. For example, the communication module 2013 transmits and receives data via the communication port 2033 to and from the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021 to 29, which are provided in the vehicle 2001.

[0432] The communication module 2013 is a communication device that can be controlled by the microprocessor 2031 of the electronic control unit 2010 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 2013 may be located either inside or outside the electronic control unit 2010. The external device may be, for example, a base station, a mobile station, or the like.

[0433] The communication module 2013 may transmit at least one of signals from the above-mentioned various sensors 2021 to 2029 input to the electronic control unit 2010, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 2012 to an external device via wireless communication. The electronic control unit 2010, the various sensors 2021 to 2029, the information service unit 2012, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include information based on the above-mentioned input.

[0434] The communication module 2013 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from an external device and displays it on the information service unit 2012 provided in the vehicle 2001. The information service unit 2012 may also be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH received by the communication module 2013 (or data / information decoded from the PDSCH)).

[0435] Furthermore, the communication module 2013 stores various information received from external devices in a memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, sensors 2021 to 2029, and the like provided in the vehicle 2001.

[0436] <Meaning and Interpretation of Terms> As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching a table, database, or other data structure), ascertaining something that is considered to be a "judging" or "determining," and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like that are considered to be a "judging" or "determining." Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0437] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0438] <Reference Signal> A reference signal can also be abbreviated as RS (Reference Signal), and may also be called a pilot depending on the applicable standard.

[0439] <Meaning of "based on"> As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0440] "First," "Second" Any reference to an element using designations such as "first," "second," etc., used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must precede the second element in some way.

[0441] <Means> The "means" in the configuration of each device above may be replaced with "section," "circuit," "device," etc.

[0442] Open Format: When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0443] <Time Units such as TTI, Frequency Units such as RB, and Radio Frame Configuration> A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0444] Numerology may be a communication parameter that applies to the transmission and / or reception of a signal or channel, and may indicate, for example, at least one of subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by the transceiver in the frequency domain, and specific windowing operations performed by the transceiver in the time domain.

[0445] A slot may be composed of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol). A slot may be a time unit based on numerology.

[0446] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0447] The radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals, and may be referred to by other names corresponding to the radio frame, subframe, slot, minislot, and symbol.

[0448] For example, one subframe may be called a transmission time interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc. instead of a subframe.

[0449] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.

[0450] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0451] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0452] A TTI having a time length of 1 ms may be called a regular TTI (TTI in LTE Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0453] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and greater than or equal to 1 ms.

[0454] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may be determined based on numerology.

[0455] The time domain of an RB may include one or more symbols and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0456] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0457] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0458] A Bandwidth Part (BWP) (which may also be referred to as a fractional bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a Common Reference Point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0459] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be configured for a UE within one carrier.

[0460] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0461] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples, and various changes may be made to the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc.

[0462] <Maximum Transmit Power> The "maximum transmit power" in the present disclosure may refer to the maximum value of transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0463] Articles In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0464] <"Different"> In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." Note that the term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0465] One aspect of the present disclosure is useful in wireless communication systems.

[0466] 10 Wireless communication system 20 NG-RAN 100 Base station (gNB) 200 Terminal (UE) 300 Wireless device 300a Control device 101, 202, 302 Transmitter 102, 201, 301 Receiver 103, 203, 303 Control unit 1001 Processor 1002 Memory 1003 Storage 1004 Communication device 1005 Input device 1006 Output device 1007 Bus

Claims

1. A control device comprising: a control unit that determines control information for controlling relaying in the antenna device based on a first direction from the antenna device that relays a signal transmitted to the wireless communication device toward the wireless communication device; and a transmission unit that transmits the control information to the antenna device.

2. The control device according to claim 1, wherein the control unit identifies a second direction from the control device toward the wireless communication device based on a result of performing beam sweep processing on the wireless communication device, and determines the first direction based on the second direction and a positional relationship between the control device and the antenna device.

3. The control device according to claim 1, wherein the control unit acquires information indicating the first direction from another control device connected to the antenna device.

4. The control device according to claim 1, wherein the control unit estimates the position of the wireless communication device based on a plurality of first directions from each of the plurality of antenna devices toward the wireless communication device, and determines the control information based on the position.

5. A wireless communication system comprising: a wireless communication device; an antenna device that relays a signal transmitted to the wireless communication device; and a control device that controls the antenna device, wherein the control device comprises: a control unit that determines control information for controlling relaying in the antenna device based on a first direction from the antenna device toward the wireless communication device; and a transmission unit that transmits the control information to the antenna device.

6. A control method, wherein a control device determines control information for controlling relaying in an antenna device based on a first direction from the antenna device that relays a signal transmitted to a wireless communication device toward the wireless communication device, and transmits the control information to the antenna device.

Images