Radio base station and terminal

Abstract

To provide a radio base station and a terminal that can efficiently and reliably execute DL directional LBT / CCA even when a plurality of beams with different directions are used.SOLUTION: A radio base station performs a channel access procedure in a second frequency band different from a first frequency band allocated for mobile communication. The radio base station sets parameters for each beam that are applied to the channel access procedure.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present disclosure relates to a radio base station and a terminal that perform wireless communication, and in particular to a radio base station and a terminal that use an unlicensed frequency band. [Background technology]

[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] 3GPP Release 15 and Release 16 (NR) specify operation in multiple frequency ranges, specifically bands including FR1 (410 MHz to 7.125 GHz) and FR2 (24.25 GHz to 52.6 GHz).

[0004] Additionally, NR, which supports frequencies above 52.6 GHz and up to 71 GHz, is also being studied (Non-Patent Document 1). In this context, channel access procedures that comply with regulations (such as Listen-Before-Talk (LBT)) that apply to unlicensed spectrum in the 52.6 GHz to 71 GHz frequency band are being studied.

[0005] Furthermore, with regard to New Radio-Unlicensed (NR-U), which expands the available frequency bands by using spectrum from such unlicensed frequency bands, 3GPP Release-16 specifies the sharing of channel occupancy time (COT) between radio base stations (gNBs) and terminals (User Equipment, UE) (Non-Patent Document 2).

[0006] COT sharing imposes several restrictions, such as transmission period, type of transmission signal / channel, and priority class. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] "New SID: Study on supporting NR from 52.6GHz to 71 GHz ", RP-193259,3GPP TSG RAN Meeting #86 , 3GPP, December 2019 [Non-patent document 2] 3GPP TS 37.213 V16.1.0, 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Physical layer procedures for shared spectrum channel access (Release 16), 3GPP, March 2020 Summary of the Invention

[0008] In the case of high frequency bands such as 52.6 GHz to 71 GHz, in order to cope with wide bandwidths and large propagation losses, it is necessary to use massive antennas with many antenna elements to generate narrower beams.

[0009] For this reason, it is thought that directional LBT / CCA (which may also be called beam-based LBT / CCA) using multiple beams will be necessary for LBT (Clear Channel Assessment (CCA)), which allows transmission within a specified period of time only if the gNB performs carrier sensing before starting transmission in an unlicensed frequency band and confirms that the channel is not being used by other nearby systems.

[0010] However, COT sharing assumes the use of the same beam (directivity), and when multiple beams with different directions are used, the gNB and UE must have a common understanding of the beam (directivity) to be applied to the downlink (DL) Directional LBT / CCA.

[0011] Furthermore, when performing directional LBT / CCA for one beam, the same directional LBT / CCA must be repeated to support multiple beams, which increases the overhead associated with LBT and hinders efficiency.

[0012] Therefore, the following disclosure has been made in consideration of this situation, and aims to provide a radio base station and a terminal that can efficiently and reliably perform DL Directional LBT / CCA even when multiple beams with different directions are used.

[0013] One aspect of the present disclosure is a radio base station (e.g., gNB100A) that includes a control unit (control unit 270) that performs a channel access procedure in a second frequency band different from a first frequency band allocated for mobile communications, and that sets parameters for each beam that are applied to the channel access procedure.

[0014] One aspect of the present disclosure is a terminal (UE) (UE200) that includes a control unit (control unit 270) that performs wireless communication in a second frequency band different from a first frequency band allocated for mobile communication, and the control unit assumes a signal or channel having the same pseudo-colocation as a synchronization signal block or reference signal indicated by downlink control information during a channel occupation time after a channel access procedure performed by a radio base station.

[0015] One aspect of the present disclosure is a terminal (UE) (UE200) that includes a control unit (control unit 270) that performs wireless communication in a second frequency band different from a first frequency band allocated for mobile communication, and the control unit assumes a signal or channel associated with a synchronization signal block or reference signal indicated by downlink control information during a channel occupation time after a channel access procedure performed by a radio base station. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram showing the overall schematic configuration of a wireless communication system 10. As shown in FIG. [Figure 2] FIG. 2 is a diagram showing frequency ranges used in the wireless communication system 10. As shown in FIG. [Figure 3] FIG. 3 is a diagram showing an example of the configuration of a radio frame, a subframe, and a slot used in the radio communication system 10. As shown in FIG. [Figure 4] Figure 4 is a functional block diagram of gNB100A and UE200. [Figure 5] Figure 5 is a diagram showing an example configuration of gNB-led COT. [Figure 6] FIG. 6 is a diagram showing an example of the execution of a channel access procedure by LBE and FBE. [Figure 7A] FIG. 7A is a diagram showing an example of the configuration of conventional directional LBT / CCA. [Figure 7B] FIG. 7B is a diagram showing a configuration example (part 1) of conventional COT sharing. [Figure 7C] FIG. 7C is a diagram showing a configuration example (part 2) of conventional COT sharing. [Figure 8] FIG. 8 is a diagram illustrating an example of the configuration of an SSB and a CSI-RS according to the first operation example. [Figure 9A] FIG. 9A is a diagram showing a configuration example (TDM) of Directional-LBT according to Operation Example 2-1. [Figure 9B] FIG. 9B is a diagram showing an example of a configuration (FDM) of Directional-LBT according to Operation Example 2-1. [Figure 9C] FIG. 9C is a diagram showing an example of the configuration (SDM) of Directional-LBT according to Operation Example 2-1. [Figure 10A] FIG. 10A is a diagram illustrating an example of the configuration (CSI-RS beam) of Directional-LBT according to Operation Example 2-2. [Figure 10B] FIG. 10B is a diagram showing an example of the configuration (SSB beam) of Directional-LBT according to Operation Example 2-2. [Figure 11] FIG. 11 is a diagram showing an example of the configuration of RS / beam for Directional-LBT according to Operation Example 2-2 (a modification of Option 2). [Figure 12A] FIG. 12A is a diagram showing an example of the configuration of Directional-LBT according to Operation Example 3 (corresponding to Operation Example 2-1). [Figure 12B] FIG. 12B is a diagram showing an example of the configuration of Directional-LBT according to Operation Example 3 (corresponding to Operation Example 2-2). [Figure 13] FIG. 13 is a diagram showing an example of the hardware configuration of gNB100A, gNB100B, and UE200. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, embodiments will be described with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions or configurations, and descriptions thereof will be omitted as appropriate.

[0018] (1) Overall configuration of the wireless communication system 1 is a schematic diagram of the overall configuration of a wireless communication system 10 according to this embodiment. The wireless communication system 10 is a wireless communication system conforming to 5G New Radio (NR) and includes a Next Generation-Radio Access Network 20 (hereinafter, NG-RAN 20) and a terminal 200 (hereinafter, UE 200).

[0019] The wireless communication system 10 may be a wireless communication system conforming to a system called Beyond 5G, 5G Evolution, or 6G.

[0020] The NG-RAN 20 includes a radio base station 100A (hereinafter, gNB100A) and a radio base station 100B (hereinafter, gNB100B). Note that the specific configuration of the radio communication system 10, including the number of gNBs and UEs, is not limited to the example shown in FIG. 1.

[0021] The NG-RAN 20 actually includes multiple NG-RAN nodes, specifically, gNBs (or ng-eNBs), and is connected to a 5G-compliant core network (5GC, not shown). The NG-RAN 20 and the 5GC may also be simply referred to as a "network."

[0022] The gNB100A and gNB100B are radio base stations conforming to 5G, and perform 5G radio communication with the UE 200. The gNB100A, gNB100B, and UE 200 are capable of supporting Massive MIMO (Multiple-Input Multiple-Output), which generates a more directional beam BM by controlling radio signals transmitted from multiple antenna elements, Carrier Aggregation (CA), which aggregates and uses multiple component carriers (CCs), and Dual Connectivity (DC), which simultaneously communicates between the UE and each of two NG-RAN nodes.

[0023] The wireless communication system 10 also supports a plurality of frequency ranges (FR).

[0024] 2, the wireless communication system 10 supports FR1 and FR2. The frequency bands of each FR are as follows:

[0025] FR1: 410 MHz to 7.125 GHz FR2: 24.25 GHz~52.6 GHz FR1 may use a Sub-Carrier Spacing (SCS) of 15, 30, 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 or 120 kHz (including 240 kHz) and a bandwidth (BW) of 50 to 400 MHz.

[0026] Note that SCS may be interpreted as numerology, which is defined in 3GPP TS38.300 and corresponds to one subcarrier spacing in the frequency domain.

[0027] Furthermore, the wireless communication system 10 also supports frequency bands higher than the FR2 frequency band. Specifically, the wireless communication system 10 supports frequency bands exceeding 52.6 GHz up to 71 GHz. For convenience, such high frequency bands may be referred to as "FR2x."

[0028] To solve this problem, when using a band above 52.6 GHz, Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) / Discrete Fourier Transform - Spread (DFT-S-OFDM) with a larger Sub-Carrier Spacing (SCS) may be applied.

[0029] FIG. 3 shows an example of the configuration of a radio frame, a subframe, and a slot used in the radio communication system 10. In FIG.

[0030] As shown in Figure 3, one slot consists of 14 symbols, and the larger (wider) the SCS, the shorter the symbol period (and slot period). The SCS is not limited to the interval (frequency) shown in Figure 3. For example, 480 kHz, 960 kHz, etc. may be used.

[0031] Also, the number of symbols constituting one slot does not necessarily have to be 14 (for example, 28 or 56 symbols). Furthermore, the number of slots per subframe may differ depending on the SCS.

[0032] The time direction (t) shown in Fig. 3 may be called a time domain, a symbol period, or a symbol time, etc. The frequency direction may be called a frequency domain, a resource block, a subcarrier, a bandwidth part (BWP), etc.

[0033] Furthermore, the wireless communication system 10 uses an unlicensed frequency band Fu that is different from the frequency band allocated for the wireless communication system 10 (for mobile communications). Specifically, the wireless communication system 10 is capable of implementing New Radio-Unlicensed (NR-U), which expands the available frequency band by using spectrum from an unlicensed frequency band. NR-U may be considered a type of Licensed-Assisted Access (LAA).

[0034] The frequency band allocated for the wireless communication system 10 is a frequency band included in the frequency ranges such as FR1 and FR2 described above, and is based on administrative license allocation.

[0035] Unlicensed frequency bands (Fu) are frequency bands that do not require government license allocation and are not restricted to specific telecommunications carriers. Examples include frequency bands used for wireless LAN (WLAN) (2.4 GHz, 5 GHz, or 60 GHz).

[0036] In the unlicensed frequency band Fu, wireless stations can be installed regardless of the specific telecommunications carrier, but it is undesirable for signals from nearby wireless stations to interfere with each other and significantly degrade communication performance.

[0037] For this reason, in Japan, for example, a requirement for wireless systems using the unlicensed frequency band Fu (e.g., the 5 GHz band) is that the gNB100A performs carrier sensing before starting transmission, and only after confirming that the channel is not being used by other nearby systems, does the Listen-Before-Talk (LBT) mechanism be applied, which allows transmission within a specified period of time. Carrier sensing is a technology that checks whether the frequency carrier is being used for other communications before emitting radio waves.

[0038] The LBT may include directional LBT / CCA (Clear Channel Assessment) using multiple beams BM pointing in different directions.

[0039] The band for LBT in NR-U (LBT sub-band) can be provided within the unlicensed frequency band Fu and may be expressed as a band for checking whether or not the unlicensed frequency band Fu is in use. The LBT sub-band may be, for example, 20 MHz, half of that, 10 MHz, or one-quarter of that, 5 MHz.

[0040] In addition, synchronization signal blocks (SSBs) are used for initial access in NR-U, as in 3GPP Release-15.

[0041] The SSB is composed of a synchronization signal (SS) and a downlink physical broadcast channel (PBCH).

[0042] The SS is composed of a primary synchronization signal (PSS: Primary SS) and a secondary synchronization signal (SSS: Secondary SS).

[0043] The PSS is a known signal that the UE 200 first attempts to detect in the cell search procedure, and the SSS is a known signal that is transmitted to detect a physical cell ID in the cell search procedure.

[0044] The PBCH includes information necessary for UE200 to establish frame synchronization with the NR cell formed by gNB100A after detecting the SS / PBCH Block, such as the radio frame number (SFN: System Frame Number) and an index for identifying the symbol positions of multiple SS / PBCH Blocks within a half frame (5 milliseconds).

[0045] The PBCH can also include system parameters required for receiving system information (SIB). Furthermore, the SSB also includes a broadcast channel demodulation reference signal (DMRS for PBCH). The DMRS for PBCH is a known signal transmitted to measure the wireless channel conditions for PBCH demodulation.

[0046] The terminal assumes that each SSB is associated with a different beam BM. In other words, the terminal assumes that each SSB is associated with a beam BM with a different transmission direction (coverage) (quasi-collocation assumption). This allows UE 200 located within the NR cell to receive one of the beam BMs, acquire the SSB, and begin initial access and SSB detection / measurement.

[0047] Quasi co-location (QCL) refers to two antenna ports being quasi-co-located when, for example, the characteristics of the channel through which symbols on one antenna port are carried can be inferred from the channel through which symbols on the other antenna port are carried. QCL may also be called quasi-co-location.

[0048] It should be noted that the transmission pattern of the SSB may vary depending on the SCS, frequency range (FR) or other parameters.

[0049] (2) Functional block configuration of wireless communication system Next, a description will be given of the functional block configuration of the wireless communication system 10. Specifically, the functional block configurations of the gNB100A and the UE200 will be described.

[0050] Figure 4 is a functional block configuration diagram of the gNB100A and the UE 200. As shown in Figure 4, the gNB100A and the UE 200 may have similar functional blocks. The gNB 100B may also have a functional block configuration similar to that of the gNB 100A.

[0051] (2.1) gNB100A As shown in Figure 4, the gNB100A includes a radio signal transceiver unit 210, an amplifier unit 220, a modulation / demodulation unit 230, a control signal / reference signal processing unit 240, an encoding / decoding unit 250, a data transceiver unit 260, and a control unit 270.

[0052] The radio signal transmitting / receiving unit 210 transmits and receives radio signals conforming to NR. The radio signal transmitting / receiving unit 210 supports Massive MIMO, CA that uses a bundle of multiple CCs, and DC that simultaneously communicates between a UE and two NG-RAN nodes.

[0053] The amplifier unit 220 is configured by a PA (Power Amplifier) / LNA (Low Noise Amplifier), etc. The amplifier unit 220 amplifies the signal output from the modulation / demodulation unit 230 to a predetermined power level. The amplifier unit 220 also amplifies the RF signal output from the radio signal transmission / reception unit 210.

[0054] The modem unit 230 performs data modulation / demodulation, transmission power setting, resource block allocation, etc. for each predetermined communication destination (UE 200). The modem unit 230 may apply Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) / Discrete Fourier Transform - Spread (DFT-S-OFDM). Furthermore, DFT-S-OFDM may be used not only for uplink (UL) but also for downlink (DL).

[0055] The control signal / reference signal processing unit 240 performs processing related to various control signals transmitted and received by the gNB100A, and processing related to various reference signals transmitted and received by the gNB100A.

[0056] Specifically, the control signal and reference signal processor 240 can transmit various control signals, for example, control signals of a radio resource control layer (RRC), to the UE 200 via a predetermined control channel. Also, the control signal and reference signal processor 240 can receive various control signals from the UE 200 via a predetermined control channel.

[0057] The control signal / reference signal processor 240 performs processing using reference signals (RS) such as a Demodulation Reference Signal (DMRS) and a Phase Tracking Reference Signal (PTRS).

[0058] DMRS is a reference signal (pilot signal) known between the base station and the terminal for estimating the fading channel used for data demodulation. PTRS is a terminal-specific reference signal for estimating phase noise, which is an issue in high frequency bands.

[0059] In addition to the DMRS and PTRS, the reference signals may include a Channel State Information-Reference Signal (CSI-RS), a Sounding Reference Signal (SRS), and a Positioning Reference Signal (PRS) for position information.

[0060] The channels include control channels and data channels, such as a PDCCH (Physical Downlink Control Channel), a PUCCH (Physical Uplink Control Channel), a RACH (Random Access Channel, Downlink Control Information (DCI) including a Random Access Radio Network Temporary Identifier (RA-RNTI)), and a Physical Broadcast Channel (PBCH).

[0061] The data channel includes a PDSCH (Physical Downlink Shared Channel) and a PUSCH (Physical Uplink Shared Channel). Data refers to data transmitted via the data channel. The data channel may be read as a shared channel.

[0062] Furthermore, with respect to NR-U, a channel may refer to a carrier or a portion of a carrier consisting of a set of contiguous resource blocks (RBs) over which a channel access procedure is performed in a shared spectrum.

[0063] The channel access procedure may be interpreted as a sensing-based procedure for assessing the availability of a channel for transmission, and the basic unit for sensing may be defined as a sensing slot having a predetermined time.

[0064] During a sensing slot period, gNB100A (or gNB100B, hereinafter the same) or UE200 senses the channel, and if the detected power is at least less than the energy detection threshold, it is considered idle; otherwise, the sensing slot period may be considered to be busy.

[0065] Additionally, "Channel Occupancy" may refer to transmission on a channel by a gNB (or eNB) / UE after performing a corresponding channel access procedure.

[0066] "Channel Occupancy Time (COT)" may refer to the total time that any gNB / UE transmits on a channel with a gNB / UE that shares the channel after the gNB / UE has performed a corresponding channel access procedure. The channel occupation time may be shared for transmission between the gNB and the corresponding UE.

[0067] A DL transmission burst may be defined as a collection of transmissions from a gNB, and a DL transmission burst having a gap larger than a predetermined transmission gap may be considered a separate DL transmission burst.

[0068] An uplink (UL) transmission burst may be defined as a collection of transmissions from a UE, and a UL transmission burst with a gap larger than a predetermined transmission gap may be considered a separate UL transmission burst.

[0069] A discovery burst may be defined as a DL transmission burst that includes a set of signals or channels confined within a predetermined window and associated with a duty cycle. A discovery burst may be designated as any of the following transmissions initiated by the gNB:

[0070] Primary Synchronization Signal (PSS) Secondary Synchronization Signal (SSS) Downlink Physical Broadcast Channel (PBCH) CORESET (control resource sets) for PDCCH that schedules PDSCH PDSCH carrying SIB1 and / or non-zero power CSI-RS In addition, in this embodiment, the control signal and reference signal processing unit 240 can transmit beam information indicating the beam BM for which the channel access procedure has succeeded, to the UE 200. In this embodiment, the control signal and reference signal processing unit 240 configures a transmission unit.

[0071] Specifically, the control signal and reference signal processor 240 can transmit information capable of identifying a beam BM for which a channel access procedure (which may be interpreted as LBT / CCA) has succeeded for the channel occupation time (COT) to the UE 200. The beam information may be transmitted by downlink control information (DCI) or may be transmitted using signaling of a higher layer (e.g., RRC).

[0072] In the case of DCI, a field for transmitting beam information may be added to DCI format 2_0, which is used to notify a group of multiple UEs 200 of the slot format.

[0073] The encoding / decoding unit 250 performs data division / concatenation and channel coding / decoding for each predetermined communication destination (UE 200).

[0074] Specifically, the encoding / decoding unit 250 divides the data output from the data transmitting / receiving unit 260 into pieces of a predetermined size, performs channel coding on the divided data, decodes the data output from the modem unit 230, and concatenates the decoded data.

[0075] The data transmitter / receiver 260 transmits and receives Protocol Data Units (PDUs) and Service Data Units (SDUs). Specifically, the data transmitter / receiver 260 assembles and disassembles PDUs / SDUs in multiple layers (such as a Medium Access Control layer (MAC), a Radio Link Control layer (RLC), and a Packet Data Convergence Protocol layer (PDCP)). The data transmitter / receiver 260 also performs data error correction and retransmission control based on Hybrid Automatic Repeat Request (Hybrid ARQ).

[0076] The control unit 270 controls each functional block that configures the gNB 100 A. In particular, in this embodiment, the control unit 270 executes control related to NR-U.

[0077] Specifically, the control unit 270 can perform a channel access procedure to access the defined channel in NR-U described above.

[0078] The channel access procedure is specified in 3GPP TS37.213. The control unit 270 can execute the channel access procedure in a frequency band (second frequency band) different from the frequency band (first frequency band) allocated for the wireless communication system 10 (for mobile communication). Specifically, the control unit 270 can execute the channel access procedure in the unlicensed frequency band Fu.

[0079] The channel access procedure performed by the gNB 100A may be referred to as a downlink (DL) channel access procedure. Note that the DL channel access procedure may include DL channel access procedures of Types 1, 2A, 2B, and 2C specified in Chapter 4.1 of 3GPP TS37.213.

[0080] The control unit 270 may set parameters for each beam BM applied to the channel access procedure. Specifically, the control unit 270 can set parameters related to directional LBT / CCA (e.g., energy detection threshold). Note that the parameters may include parameters related to a transmission period, a type of transmission signal / channel, a priority class, etc., in addition to the energy detection threshold.

[0081] The control unit 270 can perform one or more channel access procedures using at least one of spatial division multiplexing (SDM), frequency division multiplexing (FDM), and time division multiplexing (TDM). Specifically, the control unit 270 can perform a channel access procedure using multiple beams BM simultaneously using SDM, FDM, or TDM.

[0082] In this case, using a beam BM may mean transmitting a beam BM with a different transmission direction and adjusting the directivity of the antenna panel to measure whether or not there is interference using a beam BM directed in a specific direction.

[0083] Furthermore, the control unit 270 may simultaneously execute multiple channel access procedures using multiple beams BM during the channel occupation time (COT). For example, the control unit 270 may simultaneously execute channel access procedures (which may also be referred to as directional LBT / CCA) using multiple CSI-RSs, or may simultaneously execute directional LBT / CCA using multiple SSBs.

[0084] In addition, the COT may be the COT after a channel access procedure initiated by a gNB (gNB-initiated COT) or the COT after a channel access procedure initiated by a UE (UE-initiated COT).

[0085] (2.2)UE200 In the case of UE200, the functional description of gNB100A described above may be interpreted as performing the functions of UE200, i.e., UL transmission and DL reception.

[0086] In particular, in this embodiment, the control unit 270 of the UE 200 can perform wireless communication in the unlicensed frequency band Fu.

[0087] Specifically, the control unit 270 may assume a signal or channel having the same QCL as the synchronization signal block or reference signal indicated by the DCI during the channel occupation time (COT) after the channel access procedure performed by the gNB100A (or gNB100B, the same below).

[0088] More specifically, in DL transmission within the COT, the control unit 270 may assume a DL signal (which may be a reference signal) or channel (e.g., SSB, CSI-RS, PDCCH, PDSCH) having the same QCL as the SSB or reference signal (e.g., CSI-RS) indicated by DCI format 2_0, which is for notifying a group of multiple UEs 200 of a slot format.

[0089] In addition, the control unit 270 may assume a signal or channel associated with the synchronization signal block or reference signal indicated by the DCI during the channel occupation time (COT) after the channel access procedure performed by the gNB100A.

[0090] Specifically, in UL transmission (which may be interpreted as UE transmission) within the COT, the control unit 270 may consider only UL signals (which may be reference signals) or channels (e.g., SRS, PUCCH, PUSCH) that have the same spatial relation as the SSB or CSI-RS index indicated by the DCI.

[0091] Alternatively, the control unit 270 may associate the spatial relationship of the SRS associated with the UL signal or channel with the index of the SSB or CSI-RS indicated by the DCI.

[0092] (3) Operation of the wireless communication system Next, a description will be given of the operation of the wireless communication system 10. Specifically, a description will be given of the operation of the gNB100A (or gNB100B, hereinafter the same) and the UE200 regarding the DL channel access procedure (Directional LBT / CCA) using multiple beams BM.

[0093] The directional LBT / CCA according to this embodiment may be particularly suitable for use in high frequency bands such as FR2x.

[0094] (3.1) Premise In both licensed frequency bands such as FR1 and FR2 for mobile communications and the unlicensed frequency band Fu, for example, up to 64 SSBs, i.e., multiple beams BM with different directions (directivities) associated with each SSB, may be supported.

[0095] Furthermore, as described above, in order to realize channel access that complies with LBT / CCA in the unlicensed frequency band Fu, directional LBT / CCA (which may also be called beam-based LBT / CCA), i.e., a channel access procedure using multiple beams BM, may be applied.

[0096] 3GPP Release-16 NR-U allows channel occupation time (COT) sharing between the gNB 100A and the UE 200, subject to several restrictions, such as transmission duration, type of transmission signal / channel, and priority class.

[0097] The COT period (CO configuration (available LBT sub-bands, COT length)) can be indicated to a group of UEs 200 using DCI format 2_0.

[0098] Fig. 5 shows an example of the configuration of gNB-initiated COT. As shown in Fig. 5, the "channel occupation" (CO) configuration can be notified to UE 200 using DCI format 2_0. In the example shown in Fig. 5, LBT is performed in multiple LBT sub-bands, and COT (gNB-initiated COT) is set after the LBT.

[0099] When availableRB-SetPerCell-r16, which is a parameter of an upper layer (RRC), is set, the parameter may be expressed as follows, for example.

[0100] ·Available RB set Indicator 1, Available RB set Indicator 2, …, Available RB set Indicator N1, Furthermore, when CO-DurationPerCell-r16, which is a parameter of the higher layer (RRC), is set, the parameter may be expressed as follows, for example.

[0101] ·COT duration indicator 1, COT duration indicator 2, …, COT duration indicator N2. Figure 6 shows an example of the channel access procedure by LBE and FBE. Specifically, Figure 6 shows an example of the channel access procedure (LBT / CCA) by LBE (Load Based Equipment) and FBE (Frame Based Equipment) and the COT after the channel access procedure.

[0102] LBE and FBE differ in the structure of the frames and COT used for transmission and reception.

[0103] In FBE, the timing of transmission and reception related to LBT is fixed. In LBE, the timing of transmission and reception related to LBT is not fixed, and LBT can be flexibly executed according to demand, etc. In the case of LBE, a backoff time may be set to avoid collisions.

[0104] In the LBE example shown in Figure 6, multiple channel access procedures are performed over time, and a Contention Window Size (CWS) can be set according to the length of the COT. Furthermore, transmission is not permitted until the backoff time expires (the backoff counter reaches 0) to prevent collisions. As shown in Figure 6, a COT after a gNB-initiated channel access procedure is performed (gNB-initiated COT) and a COT after a UE-initiated channel access procedure is performed (UE-initiated COT) can be set.

[0105] On the other hand, in the example of FBE shown in Fig. 6, multiple channel access procedures are executed over time. However, the timing of transmission and reception related to LBT is fixed, following the Fixed Frame Period (FFP).

[0106] Furthermore, when using high frequency bands such as FR2x, it is expected that directional LBT / CCA (Beam-based LBT / CCA) using multiple beams BM with different directions will be applied to cope with wide bandwidths and large propagation losses. This can improve the success rate of channel access even in high frequency bands such as FR2x.

[0107] However, when trying to realize such directional LBT / CCA, the following problem exists with NR-U in 3GPP Release-16. Specifically, the gNB and UE need to agree on the LBT and transmission direction, but there is no method for doing so (Problem 1).

[0108] Furthermore, since only one directional LBT / CCA can be performed at a time, attempting to implement directional LBT / CCA using multiple beam BMs entails problems that hinder efficiency, such as increased LBT-related overhead (Problem 2). Since only one beam BM can be transmitted after the LBT, beam sweeping for multicast and / or broadcast signals (e.g., SSB, CSI-RS) is inefficient. Furthermore, COT sharing can only be applied to the same beam BM / direction.

[0109] Fig. 7A shows an example of the configuration of conventional directional LBT / CCA, and Fig. 7B and Fig. 7C show examples of the configuration of conventional COT sharing.

[0110] As shown in FIG. 7A, after one LBT, only one beam BM (hereinafter the same) of the same type (direction) can be transmitted, which results in low efficiency and increases overhead related to the LBT.

[0111] 7B and 7C, when only the same beam BM is shared between DL and UL, the overhead related to LBT also increases. Note that Fig. 7B shows an example of COT sharing from DL to UL (UL first), and Fig. 7C shows an example of COT sharing from UL to DL (DL first).

[0112] (3.2) Operation overview Below, we will explain operation examples 1 to 3 that solve the above-mentioned problems associated with conventional directional LBT / CCA. Operation examples 1 to 3 are outlined below.

[0113] (Example 1): Directional LBT / CCA definitions and parameters (Example 2): Support for Directional LBT / CCA using multiple beams In the second operational example, the following options may be applied.

[0114] (Option 1): Multi-directional LBT using SDM, TDM or FDM (Option 2): Directional LBT / CCA combined with novel parameters to direct LBT using multiple beams (Example 3): Instruction of multiple beams for COT and corresponding directional LBT / CCA (3.3) Example 1 In this operation example, different beams (which may be interpreted as beam widths), in other words, parameters related to LBT and / or CCA for SSB, CSI-RS, etc., may be different for each Directional LBT / CCA.

[0115] Here, the parameter typically includes, but is not limited to, the energy detection threshold as described above, and may include, for example, parameters related to the transmission period, the type of transmission signal / channel, the priority class, etc.

[0116] The energy detection threshold according to this operation example may be the same as the energy detection threshold specified in 3GPP TS36.213 Chapter 15.1.4, etc. In this case, the parameters specified in the energy detection threshold adaptation procedure in 3GPP TS36.213 Chapter 15.1.4 may be set to different values for omni-LBT and directional-LBT, which have different beams (and / or beam widths, the same applies hereinafter). Alternatively, scaling coefficients may be added to at least some of the parameters for directional-LBT, which has different beams.

[0117] In the case of SSB-based directional LBT / CCA, parameters related to the LBT (e.g., energy detection threshold) may be predefined by 3GPP specifications depending on, for example, the frequency range (FR) and SSB configuration (e.g., maximum SSB (beam) number).

[0118] For example, different values may be applied to at least some parameters for Directional LBT / CCA using different beams while using the CCA threshold equation defined in 3GPP TS 36.213. Also, scaling factors may be added for at least some parameters for Directional-LBT with different beams based on the CCA threshold equation defined in 3GPP TS 36.213.

[0119] On the other hand, in the case of directional LBT / CCA based on CSI-RS, parameters related to the LBT (for example, energy detection threshold) may be determined by any of the following.

[0120] · (Alt 1): Predefined by 3GPP specifications.

[0121] The frequency range (FR) and the CSI-RS configuration (e.g., the maximum CSI-RS (beam) number) may also be predefined. Also, similar to SSB, different values may be applied to at least some parameters for Directional LBT / CCA using different beams using the CCA threshold equation defined by 3GPP TS 36.213, and scaling factors may be added for at least some parameters for Directional-LBT with different beams.

[0122] (Alt 2): Calculate based on parameters (related to QCL-type D) for SSB-based Directional LBT / CCA according to the CSI-RS settings (e.g., the maximum CSI-RS beam number, and the maximum CSI-RS beam number with QCL type D associated with SSB).

[0123] · (Alt 3): Not supported, i.e. only SSB-based Directional LBT / CCA may be supported.

[0124] The QCL type is specified as follows in Chapter 5.1.5 of 3GPP TS38.214:

[0125] ·QCL-Type A: {Doppler shift, Doppler spread, average delay, delay spread} ·QCL-Type B: {Doppler shift, Doppler spread} ·QCL-Type C: {Doppler shift, average delay} ·QCL-Type D: {Spatial Rx parameter} 8 shows an example of the configuration of SSBs and CSI-RSs according to Operation Example 1. In FIG. 8, CSI-RSs #1 to #4 are associated with SSB #1 and are QCL-Type D.

[0126] In addition, the energy detection threshold for directional LBT / CCA based on CSI-RS #1 to #4 may be pre-defined according to the 3GPP specifications, calculated based on the threshold for directional LBT / CCA based on SSB #1, or may not be supported.

[0127] (3.4) Example 2 In this operation example, operations according to the above-mentioned options 1 and 2 will be described.

[0128] (3.4.1) Example 2-1 In Option 1, one or more Directional-LBTs (SSB or CSI-RS based LBTs) may be performed for CCA using SDM, TDM, or FDM. In this case, transmission after CCA is possible only for beam directions where LBT was successful (i.e., interference below the energy detection threshold was detected).

[0129] It is desirable that the beam for SSB / CSI-RS / PDCCH / PDSCH transmitted after LBT_idle (see Figure 6) has the same QCL-Type D (Spatial Rx parameter) as the beam for Directional-LBT based on SSB / CSI-RS.

[0130] Furthermore, SDM, TDM or FDM may also be applied in the COT to SSB / CSI-RS / PDCCH / PDSCH transmitted after LBT_idle.

[0131] 9A, 9B, and 9C show configuration examples of Directional-LBT according to Operation Example 2-1. Specifically, Fig. 9A, 9B, and 9C show configuration examples of Directional-LBT to which TDM, FDM, and SDM are applied, respectively.

[0132] As shown in Fig. 9A, transmission (TX) may not be performed on an LBT_busy beam (i.e., a beam that has interference and failed LBT). In Fig. 9A, multiple beams are multiplexed in a time-division manner, so beams with different directions may be used for each predetermined time (period). In FIG. 9B, multiple beams are multiplexed by frequency division, so that beams with different directions may be used for each predetermined frequency band (which may be a subcarrier or a resource block (RB)).

[0133] In FIG. 9C, multiple beams are multiplexed in a spatial division manner, so that multiple beams with different directions may be used in the same time or frequency domain.

[0134] Note that the SDM option may only be applied to some channel access types, i.e., types of channel access procedures (e.g., Types 2A, 2B, and 2C as specified in 3GPP TS37.213), which may be interpreted as channel access procedures performed in the period spanned by slots detected as idle before DL transmission is deterministic.

[0135] In addition, one or more schemes of TDM, FDM, or SDM-applied Directional-LBT may be supported.

[0136] In Option 1, the following options may also apply:

[0137] (Option 1-1): For gNBs that perform transmission using a single antenna panel (i.e., gNBs that do not support simultaneous transmission of multiple beams), Directional-LBT with TDM is supported.

[0138] (Option 1-2): For gNBs that perform transmission using multiple antenna panels (multi-panel) (i.e., gNBs that support simultaneous transmission of multiple beams), Directional-LBT with at least one of TDM, FDM, and SDM applied is supported.

[0139] In addition, in the case of Directional-LBT to which FDM is applied, the operation may be as follows.

[0140] (Case 1): For example, Directional-LBT for beam direction A may be performed in some LBT sub-bands, and transmission may be determined only in those sub-bands.

[0141] At the same time, the LBT sub-band for beam direction B may be performed in another LBT sub-band and determine transmission only in that sub-band. Specifically, the example on the left side of FIG. 9B corresponds to Case 1.

[0142] (Case 2): For example, directional LBT for beam direction A can be performed in some LBT sub-bands, and the results of the LBT in those sub-bands are assumed to be the results of the LBT in the wider band (based on some conditions, such as a higher CCA threshold than the LBT in those sub-bands).

[0143] At the same time, LBT sub-band for beam direction B can be performed in another LBT sub-band, and the results of LBT in that sub-band may be applied to transmission in a wider band. In this case, only the LBT_idle beam may be transmitted. Specifically, the examples in the center and right of FIG. 9B correspond to Case 2. In other words, if Directional-LBT for beam direction A is successful, it may be assumed that beam direction B is also available for COT.

[0144] Furthermore, in the case of Directional-LBT to which SDM is applied, in CCA, LBT may be executed simultaneously for the directions corresponding to a plurality of beams.

[0145] A gNB that performs transmission using multiple panels may simultaneously transmit and receive different beams using different panels, and therefore may sense interference by applying different reception spatial parameters to different beam directions using different panels.

[0146] In this case, as long as the isolation between beams / panels is good enough, the results of simultaneous sensing will be accurate and will not include interference with other beams / panels.

[0147] Furthermore, after CCA, the beams used for actual transmission may depend on the results of CCA, specifically, only beam directions for which CCA is successful may be considered.

[0148] (3.4.2) Example 2-2 In the case of Option 2, for CCA, a combination of Directional-LBT using novel parameters may represent (instruct) a multiple beam (e.g., SSB / CSI-RS beam) based LBT.

[0149] If the Directional-LBT is successful, the multiple beams may be used for transmission in all directions, whereas if the Directional-LBT is unsuccessful, transmission in all directions using the multiple beams may not be permitted.

[0150] The supported combinations may be predefined by the 3GPP specifications, or an appropriate combination may be configured (notified) to UE 200 by signaling of a higher layer (such as RRCN) or a lower layer (such as DCI).

[0151] Examples of such combinations include the following:

[0152] (Combination example 1): Set (instructed) by 3GPP specifications or RRC / MAC CE (Control Element) / DCI.

[0153] ·Combined directional LBT conf.1:(normal LBT parameters including CCA threshold), CSI-RS#1,#2,#3,#4 ·Combined directional LBT conf.2:(normal LBT parameters including CCA threshold), CSI-RS#5,#6,#7,#8 ·Combined directional LBT conf.3:(normal LBT parameters including CCA threshold), CSI-RS#1,#2 ·Combined directional LBT conf.4: (normal LBT parameters including CCA threshold), CSI-RS#3,#4, etc. (Combination example 2): Set (instructed) by 3GPP specifications or RRC / MAC CE / DCI.

[0154] ·Combined directional LBT conf.1: (normal LBT parameters including CCA threshold), SSB#0~#7 ·Combined directional LBT conf.2: (normal LBT parameters including CCA threshold), SSB#8~#15,… ·Combined directional LBT conf.8: (normal LBT parameters including CCA threshold), SSB#56~#63 Combination example 1 shows an example based on multiple CSI-RS beams. The number of CSI-RS (indexes) included in this combination is not particularly limited.

[0155] Combination Example 2 shows an example based on multiple SSB beams. The number of SSBs (indexes) included in the combination is not particularly limited. In the above example, 64 SSBs (SSB indexes #0 to #63) are divided into eight combinations.

[0156] 10A and 10B show configuration examples of Directional-LBT according to Operation Example 2-2. Specifically, Fig. 10A shows a configuration example of Directional-LBT based on a CSI-RS beam (Combined directional LBT conf.3). Fig. 10B shows a configuration example of Directional-LBT based on an SSB beam (Combined directional LBT conf.1).

[0157] In the case of such Directional-LBT, it is desirable that the beam for SSB / CSI-RS / PDCCH / PDSCH transmitted after LBT_idle is the same as at least one of the beams of the combination or has QCL-Type D (Spatial Rx parameter).

[0158] Furthermore, in the case of Option 2, the following changes may be made. Specifically, a new reference signal (RS) and / or beam indicating the beam direction used in DL Directional-LBT may be defined. The index of the RS and / or beam for DL Directional-LBT may be predefined and set to correspond to one or more beam directions (specifically, SSB / CSI-RS) used for DL transmission.

[0159] If the Directional-LBT is successful, the direction corresponding to the beam (i) may be targeted for transmission. For example, a new DL_LBT_RS / beam may be defined, and the RRC may set up the following association:

[0160] DL_LBT_RS / beam 1: Compatible with SSB#0~#7 DL_LBT_RS / beam 2: Compatible with SSB#8~#15 ·… DL_LBT_RS / beam 8: Compatible with SSB#56~#63 FIG. 11 shows an example of the configuration of RS / beam for Directional-LBT according to Operation Example 2-2 (a modification of Option 2).

[0161] Specifically, Fig. 11 shows an example of DL_LBT_RS / beam 1. As shown in Fig. 11, DL_LBT_RS / beam 1 includes SSBs #0 to #7. DL_LBT_RS / beam 1 used for beam-based LBT / CCA is omnidirectional and is shown as a circle. On the other hand, SSBs #0 to #7 are used for transmission in the corresponding beams and may have directionality and are shown as ellipses.

[0162] (3.5) Example 3 In this operation example, when Directional-LBT is activated or configured by signaling of a higher layer (e.g., RRC), in order to support COT sharing of multiple beams from DL to UL, information of beams for which LBT was successful, specifically, the index of SSB / CSI-RS, may be indicated to a group of multiple UEs 200.

[0163] This instruction may be realized by an extension of DCI format 2_0 or a new DCI format. This DCI format may include at least one of the following information (which may be applied to operation example 2-1 and operation example 2-2):

[0164] SSB / CSI-RS index Index of the set of multiple beams set by RRC (e.g., index of the Directional-LBT combination with new parameters) Index of the set of multiple beams activated by the RRC and MAC CE Also, for DL transmission within the COT, UE 200 may expect only DL RSs and / or channels (e.g., SSB / CSI-RS / PDCCH / PDSCH) that have the same QCL-Type D as the SSB or CSI-RS index indicated by the DCI.

[0165] Furthermore, for UL transmission (UE transmission) within the COT, UE 200 may expect only UL RSs and / or channels (SRS / PUCCH / PUSCH) that have the same spatial relation as the indicated SSB, and the spatial relation of the SRS associated with the RS and / or channel may be associated with the index of the specified SSB or CSI-RS in the DCI.

[0166] Alternatively, for UL transmissions (UE transmissions) during the COT sharing period, UE 200 may switch the corresponding UL transmissions from the Type 1 channel access procedure to the Type 2A channel access procedure at determined positions in the frequency and time domains within the remaining channel occupancy only for UL transmissions that have the same spatial relationship as the index of the SSB or CSI-RS indicated by the DCI, or for which the spatial relationship of the SRS associated with the RS and / or channel is associated with the index of the SSB or CSI-RS indicated by the DCI.

[0167] 12A and 12B show configuration examples of Directional-LBT according to Operation Example 3. Specifically, Fig. 12A shows an example of COT sharing based on Operation Example 2-1. Fig. 12A shows an example in which CSI-RS #1, 2, and 4 are designated for COT use by DCI (CSI-RS #3 is excluded due to being busy).

[0168] 12B shows an example of COT sharing based on operation example 2-2. In FIG. 12B, an example is shown in which the DCI instructs Combined directional LBT conf.1 (targeting CSI-RS#1, #2, #3, and #4) to be used for COT.

[0169] (4) Actions and Effects According to the above-described embodiment, the following advantageous effects can be obtained. Specifically, the gNB 100A (and the gNB 100B, hereinafter the same) can perform a channel access procedure in a frequency band (unlicensed frequency band Fu) different from the frequency band (first frequency band) allocated for the wireless communication system 10 (for mobile communications). Furthermore, the gNB 100A can set parameters for each beam BM to be applied to the channel access procedure.

[0170] Therefore, even when multiple beams BM are used to support high frequency bands such as FR2x, the gNB 100A and the UE 200 can have a common understanding of the beams (directivity) applied to DL Directional LBT / CCA. Furthermore, setting parameters for each beam BM can also contribute to suppressing an increase in overhead related to LBT.

[0171] This makes it possible to efficiently and reliably perform DL directional LBT / CCA even when multiple beams BM with different directions are used.

[0172] In this embodiment, the gNB 100A can perform a channel access procedure using multiple beams BM simultaneously using SDM, FDM, or TDM, thereby enabling efficient DL directional LBT / CCA.

[0173] In this embodiment, the gNB 100A can simultaneously perform multiple channel access procedures using multiple beams BM in the COT, which allows for more efficient DL directional LBT / CCA.

[0174] In this embodiment, the gNB 100A can transmit beam information indicating the beam BM for which the channel access procedure was successful for COT to the UE 200. Therefore, the UE 200 can easily recognize the appropriate beam BM.

[0175] In this embodiment, the UE 200 may assume a signal or channel having the same QCL as the SSB or reference signal (CSI-RS) indicated by the DCI in the COT after the channel access procedure performed by the gNB 100A. This can facilitate appropriate communication (e.g., DL transmission) taking into account the directionality of the beam BM.

[0176] In this embodiment, the UE 200 may assume a signal or channel associated with the SSB or reference signal (CSI-RS) indicated by the DCI in the COT after the channel access procedure performed by the gNB 100A. This may facilitate appropriate communication (e.g., UL transmission) taking into account the directionality of the beam BM.

[0177] (5) Other embodiments Although the embodiments have been described above, it will be obvious to those skilled in the art that the present invention is not limited to the description of the embodiments and that various modifications and improvements are possible.

[0178] For example, in the above-described embodiment, an example has been described in which the SSB and the CSI-RS are associated with the beam BM, but the reference signal is not necessarily limited to the CSI-RS. Any other signal may be used as long as it can identify the association with the direction (directivity) of the beam BM.

[0179] Unlicensed spectrum may also be referred to by different names, such as license-exempt or licensed-assisted access (LAA).

[0180] The block diagram (FIG. 4) used in the description of the above-described embodiment shows 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 connected directly or indirectly (for example, by wire, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining the single device or multiple devices with software.

[0181] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, 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 each is implemented.

[0182] Furthermore, the above-described gNB100A, gNB100B, and UE200 (the devices) may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 13 is a diagram showing an example of the hardware configuration of the devices. As shown in Fig. 13, the devices may be 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.

[0183] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the apparatus 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.

[0184] Each functional block of the device (see FIG. 4) is realized by any hardware element of the computer device or a combination of the hardware elements.

[0185] In addition, each function of the device is realized by loading specified software (programs) onto hardware such as processor 1001 and memory 1002, causing processor 1001 to perform calculations, control communication via communication device 1004, and control at least one of reading and writing data in memory 1002 and storage 1003.

[0186] The processor 1001 controls the entire computer by running, for example, an operating system, and may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control unit, an arithmetic unit, a register, and the like.

[0187] 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-mentioned embodiments. Furthermore, the various processes described above may be executed by one processor 1001, or may 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 be transmitted from a network via a telecommunications line.

[0188] 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 a program (program code), a software module, etc., that can execute a method according to an embodiment of the present disclosure.

[0189] Storage 1003 is a computer-readable recording medium, and may be, for example, at least one of an optical disk such as a Compact Disc ROM (CD-ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy disk, a magnetic strip, etc. Storage 1003 may also be referred to as an auxiliary storage device. The above-mentioned recording medium may be, for example, a database, a server, or other appropriate medium including at least one of memory 1002 and storage 1003.

[0190] 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 called, for example, a network device, a network controller, a network card, or a communication module.

[0191] The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize, for example, at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD).

[0192] The input device 1005 is an input device (for example, 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 (for example, 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 (for example, a touch panel).

[0193] Furthermore, each device such as the processor 1001 and the memory 1002 is connected to 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.

[0194] Furthermore, the device 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, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0195] Furthermore, the notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the 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., RRC signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB))), other signals, or a combination thereof. Furthermore, the 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.

[0196] Each aspect / embodiment described in the present disclosure may be applied to at least one of a system using Long Term Evolution (LTE), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, a 4th generation mobile communication system (4G), a 5th generation mobile communication system (5G), Future Radio Access (FRA), New Radio (NR), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other suitable system, and a next-generation system extended based on these. Furthermore, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A and 5G) may also be applied.

[0197] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless it is consistent. 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.

[0198] In the present disclosure, a specific operation 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.

[0199] Information, signals (information, etc.) may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0200] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be sent to another device.

[0201] The determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0202] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, 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).

[0203] 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.

[0204] 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.

[0205] The 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. that 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.

[0206] Note that terms explained 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.

[0207] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0208] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0209] 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.

[0210] In this 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. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0211] A base station can accommodate one or more (e.g., three) cells (also called sectors). When a base station accommodates multiple cells, the overall coverage area of the base station can be divided into multiple smaller areas, and each smaller area can be provided with communication services by a base station subsystem (e.g., a small indoor base station (Remote Radio Head: RRH)).

[0212] The terms "cell" or "sector" refer to part or all of the coverage area of a base station and / or base station subsystem that provides communication services within that coverage area.

[0213] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0214] 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.

[0215] At least one of the base station and the mobile station may be called 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, or the mobile object itself. The mobile object 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 also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0216] Furthermore, a base station in the present disclosure may be read as a mobile station (user terminal, the same applies hereinafter). For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a mobile station is replaced with communication between multiple mobile stations (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the mobile station may be configured to have the functions of a base station. 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 uplink channel and downlink channel may be read as side channel.

[0217] Similarly, a mobile station in the present disclosure may be interpreted as a base station, in which case the base station may have the functions of a mobile station. 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.

[0218] Numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, such as 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 a transceiver in the frequency domain, and specific windowing operations performed by a transceiver in the time domain.

[0219] A slot may consist of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol, etc.) A slot may be a numerology-based time unit.

[0220] A slot may include multiple minislots. Each minislot may consist of one or more 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.

[0221] 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.

[0222] 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 (e.g., 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.

[0223] 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. However, the definition of TTI is not limited to this.

[0224] 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.

[0225] 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.

[0226] 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.

[0227] 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 equal to or greater than 1 ms.

[0228] A resource block (RB) is a resource allocation unit in the time domain and 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 also be determined based on numerology.

[0229] The time domain of an RB may include one or more symbols and may be one slot, one minislot, one subframe, or one TTI in length. Each TTI, subframe, etc. may be composed of one or more resource blocks.

[0230] 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, or the like.

[0231] 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.

[0232] 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 given BWP and numbered within that BWP.

[0233] 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.

[0234] 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."

[0235] The above-described structures of the radio frame, subframe, slot, minislot, and symbol are merely examples. For example, 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, and other configurations can be changed in various ways.

[0236] 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.

[0237] The reference signal may also be abbreviated as Reference Signal (RS), and may also be called a pilot depending on the applicable standard.

[0238] 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."

[0239] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0240] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. 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 therein or that the first element must precede the second element in some way.

[0241] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0242] 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.

[0243] 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 in a table, database, or other data structure), ascertaining, 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. 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.

[0244] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." 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."

[0245] 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. [Explanation of symbols]

[0246] 10. Wireless communication systems 20 NG-RAN 100A, 100B gNB 200 UE 210 Radio signal transmitter / receiver 220 Amplifier section 230 Modulation and Demodulation Unit 240 Control signal / reference signal processing section 250 Encoding / Decoding Unit 260 Data transmission and reception unit 270 Control Unit 1001 processor 1002 memory 1003 Storage 1004 Communication equipment 1005 Input Device 1006 Output Device 1007 Bus

Claims

1. a transmitter for performing time-division multiplexed DL transmissions with different beams over a channel; a control unit for performing channel access procedures in a shared spectrum; Equipped with The control unit is a radio base station that executes the channel access procedure simultaneously in the directions corresponding to a plurality of beams before the DL transmission.

2. The radio base station according to claim 1 , wherein the control unit executes the channel access procedure in a frequency band higher than a frequency band of frequency range 1, FR1.

3. performing time division multiplexed DL transmissions with different beams over the channel; performing a channel access procedure in a shared spectrum; Including, The channel access procedure is a communication method in a radio base station in which multiple beams are simultaneously executed in corresponding directions before the DL transmission.

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