Method and device for executing channel access process

Abstract

A method for transmitting an uplink signal by a user equipment (UE) in a wireless communication system is disclosed. Specifically, the method includes performing a listen-before-talk (LBT) operation based on at least one LBT beam and, based on the success of the LBT operation, transmitting the uplink signal via multiple transmission beams. The at least one LBT beam covers multiple transmission beams, and the multiple transmission beams are multiplexed.

Description

Technical Field

[0001] The present disclosure relates to a method and apparatus for performing a channel access procedure, and more particularly, to a method and apparatus for performing a channel access procedure for transmitting and receiving signals through a multiplexed transmission beam. Background Art

[0002] As more and more communication devices require greater communication services in line with the current trend, the next-generation fifth-generation (5G) system is needed to provide enhanced wireless broadband communications compared to the traditional LTE system. In the next-generation 5G system, communication scenarios are divided into enhanced mobile broadband (eMBB), ultra-reliable and low-latency communication (URLLC), massive machine type communication (mMTC), etc.

[0003] In this article, eMBB is a next-generation mobile communication scenario characterized by high spectral efficiency, high user experience data rate, and high peak data rate, URLLC is a next-generation mobile communication scenario characterized by ultra-high reliability, ultra-low latency, and ultra-high availability (e.g., vehicle-to-everything (V2X), emergency services, and remote control), and mMTC is a next-generation mobile communication scenario characterized by low cost, low energy, short packets, and massive connections (e.g., the Internet of Things (IoT)). Summary of the Invention

[0004] Technical issues

[0005] The present disclosure aims to provide a method and apparatus for performing a channel access procedure.

[0006] Those skilled in the art will appreciate that the objectives that can be achieved by the present disclosure are not limited to the contents specifically described above, and the above and other objectives that can be achieved by the present disclosure will be more clearly understood from the following detailed description.

[0007] Technical Solution

[0008] According to one aspect of the present disclosure, a method for transmitting an uplink signal by a user equipment (UE) in a wireless communication system is provided, comprising: performing a listen-before-talk (LBT) based on at least one LBT beam; and transmitting the uplink signal through multiple transmission beams based on a success of the LBT. The at least one LBT beam may cover multiple transmission beams, and the multiple transmission beams may be multiplexed.

[0009] Multiple transmission beams may be multiplexed using spatial division multiplexing (SDM).

[0010] Time division multiplexing (TDM) may be used to multiplex multiple transmission beams.

[0011] The at least one LBT beam may be a single LBT beam covering all of the plurality of transmission beams.

[0012] The at least one LBT beam may include a plurality of LBT beams, and each of the plurality of LBT beams may cover each of the plurality of transmission beams.

[0013] Category 2 (Cat-2) LBT may be performed before beam switching is performed between multiple transmission beams.

[0014] In another aspect of the present disclosure, a user equipment (UE) for transmitting an uplink signal in a wireless communication system is provided, comprising: at least one transceiver; at least one processor; and at least one memory operably connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations. The operations may include: performing listen-before-talk (LBT) based on at least one listen-before-talk (LBT) beam; and transmitting, by the at least one transceiver, an uplink signal using multiple transmission beams based on the success of the LBT. The at least one LBT beam may cover multiple transmission beams, and the multiple transmission beams may be multiplexed.

[0015] Multiple transmission beams may be multiplexed using spatial division multiplexing (SDM).

[0016] Time division multiplexing (TDM) may be used to multiplex multiple transmission beams.

[0017] The at least one LBT beam may be a single LBT beam covering all of the plurality of transmission beams.

[0018] The at least one LBT beam may include a plurality of LBT beams, and each of the plurality of LBT beams may cover each of the plurality of transmission beams.

[0019] Category 2 (Cat-2) LBT may be performed before beam switching is performed between multiple transmission beams.

[0020] In another aspect of the present disclosure, an apparatus for transmitting an uplink signal in a wireless communication system is provided, comprising: at least one processor; and at least one memory operably connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations. The operations may include: performing a listen-before-talk (LBT) based on at least one LBT beam; and transmitting the uplink signal via multiple transmission beams based on a success of the LBT. The at least one LBT beam may cover multiple transmission beams, and the multiple transmission beams may be multiplexed.

[0021] In another aspect of the present disclosure, a computer-readable storage medium including at least one computer program for causing at least one processor to perform operations may include: performing listen-before-talk (LBT) based on at least one LBT beam; and transmitting uplink signals via multiple transmission beams based on the success of the LBT. The at least one LBT beam may overlap multiple transmission beams, and the multiple transmission beams may be multiplexed.

[0022] In another aspect of the present disclosure, a method for transmitting a downlink signal by a base station in a wireless communication system is provided, comprising: performing listen-before-talk (LBT) based on at least one LBT beam, and transmitting the downlink signal through multiple transmission beams based on a success of the LBT. The at least one LBT beam may cover multiple transmission beams, and the multiple transmission beams may be multiplexed.

[0023] In another aspect of the present disclosure, a base station for transmitting downlink signals in a wireless communication system is provided, comprising: at least one transceiver; at least one processor; and at least one memory operably connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations. The operations may include: performing listen-before-talk (LBT) based on at least one listen-before-talk (LBT) beam; and transmitting, by the at least one transceiver, the downlink signal using multiple transmission beams based on the success of the LBT. The at least one LBT beam may cover multiple transmission beams, and the multiple transmission beams may be multiplexed.

[0024] Beneficial effects

[0025] According to the present disclosure, in order to overcome the relatively large path loss occurring in high frequency bands of 52.6 GHz or higher, the BS and / or UE may use directional listen-before-talk (D-LBT), and when multiplexing transmission beams in different directions within the obtained channel occupancy time (COT), appropriate energy detection (ED) values, LBT bandwidths and / or LBT beams for the multiplexed transmission beams may be configured.

[0026] Those skilled in the art will recognize that the effects that can be achieved using the present disclosure are not limited to the contents specifically described above, and other advantages of the present disclosure will be more clearly understood from the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 illustrates physical channels in a 3rd Generation Partnership Project (3GPP) system as an exemplary wireless communication system and a general signal transmission method using the same;

[0028] Figure 2 Figure 1 shows the radio frame structure;

[0029] Figure 3 illustrating a resource grid during the duration of a time slot;

[0030] Figure 4 illustrates an exemplary mapping of physical channels in time slots;

[0031] Figure 5 illustrates an exemplary uplink (UL) transmission operation of a user equipment (UE);

[0032] Figure 6 illustrates an exemplary repeated transmission of a grant based on configuration;

[0033] Figure 7 The figure shows a wireless communication system supporting unlicensed bands;

[0034] Figure 8 An exemplary method of occupying resources in an unlicensed band is illustrated;

[0035] Figure 9 An exemplary channel access procedure of a UE for UL signal transmission and / or DL ​​signal transmission in an unlicensed band applicable to the present disclosure is illustrated;

[0036] Figure 10 is a diagram illustrating a plurality of listen-before-talk sub-bands (LBT-SBs) suitable for use in the present disclosure.

[0037] Figure 11 is a diagram illustrating analog beamforming in an NR system;

[0038] Figure 12 、 13 , 14, 15 and 16 are diagrams illustrating beam management in an NR system;

[0039] Figure 17 and 18 is a diagram illustrating a sounding reference signal applicable to the present disclosure;

[0040] Figure 19 is a diagram illustrating beam-based LBT and group-based LBT according to an embodiment of the present disclosure;

[0041] Figure 20 is a diagram illustrating problems occurring when beam-based LBT is performed according to an embodiment of the present disclosure.

[0042] Figure 21 and 22 is a diagram illustrating an overall operation process of a UE and a BS according to an embodiment of the present disclosure;

[0043] Figure 23 、24 25 are diagrams illustrating a method of performing LBT on a plurality of multiplexed beams according to an embodiment of the present disclosure;

[0044] Figure 26 An exemplary communication system applicable to the present disclosure is illustrated;

[0045] Figure 27 An exemplary wireless device suitable for use with the present disclosure is illustrated; and

[0046] Figure 28 An exemplary vehicle or autonomous vehicle suitable for use with the present disclosure is illustrated. DETAILED DESCRIPTION

[0047] The following technologies can be used in various wireless access systems, such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), etc. CDMA can be implemented as a radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented as a radio technology such as Global System for Mobile Communications (GSM) / General Packet Radio Service (GPRS) / Enhanced Data Rates for GSM Evolution (EDGE). OFDMA can be implemented as a radio technology such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wireless Fidelity (Wi-Fi)), IEEE 802.16 (Worldwide Interoperability for Microwave Access (WiMAX)), IEEE 802.20, Evolved UTRA (E-UTRA), etc. UTRA is part of Universal Mobile Telecommunications System (UMTS). 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is part of Evolved UMTS (E-UMTS) using E-UTRA, and LTE-Advanced (LTE-A) is an evolution of 3GPP LTE. 3GPP New Radio or New Radio Access Technology (NR) is an evolved version of 3GPP LTE / LTE-A.

[0048] Although the following description is given in the context of a 3GPP communication system (e.g., NR) for clarity, the technical spirit of the present disclosure is not limited to the 3GPP communication system. For background technology, the terms and abbreviations used in this disclosure refer to technical specifications published before this disclosure (e.g., 38.211, 38.212, 38.213, 38.214, 38.300, 38.331, etc.).

[0049] 5G communication involving a new radio access technology (NR) system will be described below.

[0050] The three key requirement areas for 5G are (1) enhanced mobile broadband (eMBB), (2) massive machine-type communications (mMTC), and (3) ultra-reliable and low-latency communications (URLLC).

[0051] Some use cases may require optimization across multiple dimensions, while others may focus on just one key performance indicator (KPI). 5G supports this diverse range of use cases in a flexible and reliable manner.

[0052] eMBB goes far beyond basic mobile internet access and encompasses rich interactive work, media, and entertainment applications in the cloud or augmented reality (AR). Data is one of the key drivers of 5G, and in the 5G era, we may see, for the first time, no dedicated voice services. In 5G, voice is expected to be simply processed as an application using the data connection provided by the communications system. The main drivers of increased traffic are the increase in content size and the number of applications requiring high data rates. As more devices connect to the internet, streaming services (audio and video), interactive video, and mobile internet connectivity will continue to become more widely used. Many of these applications require always-on connectivity to deliver real-time information and notifications to users. For mobile communication platforms, cloud storage and applications are rapidly increasing. This applies to both work and entertainment. Cloud storage is a specific use case driving the growth of uplink data rates. 5G will also be used for remote work in the cloud, which, when accomplished using tactile interfaces, requires much lower end-to-end latency to maintain a good user experience. Entertainment (e.g., cloud gaming and video streaming) is another key driver of increased mobile broadband capacity demand. Entertainment is very important on smartphones and tablets anywhere, including in high-mobility environments such as trains, cars, and airplanes. Another use case is AR and information search for entertainment, which requires very low latency and large amounts of real-time data.

[0053] One of the most anticipated 5G use cases is the ability to proactively connect embedded sensors in every field, known as mMTC. It is estimated that there will be 20.4 billion potential Internet of Things (IoT) devices by 2020. In the Industrial IoT, 5G is one of the areas that will play a key role in enabling smart cities, asset tracking, smart utilities, agriculture, and secure infrastructure.

[0054] URLLC includes services that will transform industries by leveraging ultra-reliable / available low-latency links, such as remote control of critical infrastructure and autonomous vehicles. Reliability and latency levels are crucial for smart grid control, industrial automation, robotics, drone control and coordination, and more.

[0055] Now, multiple use cases in a 5G communication system including an NR system will be described in detail.

[0056] 5G can complement fiber-to-the-home (FTTH) and cable-based broadband (or Data-over-Cable Service Interface Specification (DOCSIS)) as a means of delivering streams at data rates ranging from hundreds of megabits per second to gigabits per second. Such high speeds are needed for television broadcasts with resolutions of 4K (6K, 8K, and higher) or higher, as well as for virtual reality (VR) and AR. VR and AR applications primarily include immersive sports gaming. Specific applications may require special network configurations. For example, for VR gaming, gaming companies may have to integrate core servers with network operators' edge network servers to minimize latency.

[0057] The automotive industry is expected to be a significant new driver of 5G, with numerous use cases for mobile communications within vehicles. For example, passenger entertainment will require both high-capacity and high-mobility mobile broadband, as future users will expect continued high-quality connectivity regardless of their location and speed. Another automotive use case is augmented reality dashboards. These displays overlay information on what the driver sees through the front window, identifying objects in the dark and informing the driver of their distance and movement. In the future, wireless modules will enable communication between vehicles, between vehicles and supporting infrastructure, and between vehicles and other connected devices (such as those carried by pedestrians). Safety systems can guide drivers on alternative courses of action, allowing them to drive more safely and reduce the risk of accidents. The next stage will be remotely controlled or autonomous vehicles. These require extremely reliable and fast communications between autonomous vehicles and between vehicles and infrastructure. In the future, autonomous vehicles will perform all driving activities, while drivers focus on elusive traffic anomalies. Autonomous vehicle technology will require ultra-low latency and ultra-high reliability, raising traffic safety to levels previously unattainable by humans.

[0058] Smart cities and smart homes (often referred to as smart societies) will be embedded with dense wireless sensor networks. Distributed networks of smart sensors will identify conditions for cost and energy-saving maintenance in a city or home. A similar setup can be implemented for each home, where temperature sensors, window and heating controls, burglar alarms, and home appliances are all wirelessly connected. Many of these sensors are typically characterized by low data rates, low power, and low cost, but real-time high-definition (HD) video may be required for surveillance, for example, in certain types of equipment.

[0059] The consumption and distribution of energy (including heat or gas) is becoming highly decentralized, creating a need for automated control of highly distributed sensor networks. Smart grids interconnect these sensors, using digital information and communication technologies to collect and act on information. This information can include information about the behavior of suppliers and consumers, allowing smart grids to improve the efficiency, reliability, affordability, and sustainability of the production and distribution of fuels such as electricity in an automated manner. Smart grids can be viewed as another sensor network with low latency.

[0060] The health sector has many applications that can benefit from mobile communications. Communication systems enable telemedicine, which provides remote clinical health care. It helps eliminate distance barriers and improves access to medical services, which are often not always available in remote rural communities. It is also used to save lives in critical care and emergency situations. Wireless sensor networks based on mobile communications can provide remote monitoring and sensors for parameters such as heart rate and blood pressure.

[0061] Wireless and mobile communications are becoming increasingly important for industrial applications. Wires are expensive to install and maintain, and the possibility of replacing them with reconfigurable wireless links presents an attractive opportunity for many industries. However, achieving this requires wireless connections to operate with latency, reliability, and capacity similar to wired connections, while also simplifying their management. Low latency and very low error rates are new requirements that 5G will address.

[0062] Finally, logistics and freight tracking are important use cases for mobile communications, enabling inventory and packages to be tracked anytime, anywhere through the use of location-based information systems. Logistics and freight tracking use cases typically require lower data rates but require wide coverage and reliable location information.

[0063] Figure 1 Illustration of physical channels in a 3GPP system and a general signal transmission method using the physical channels.

[0064] When the UE is powered on or enters a new cell, the UE performs an initial cell search (S11). The initial cell search involves acquiring synchronization with the BS. To this end, the UE receives a synchronization signal block (SSB) from the BS. The SSB includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a physical broadcast channel (PBCH). The UE synchronizes its timing with the BS and obtains information such as a cell identifier (ID) based on the PSS / SSS. In addition, the UE can obtain information broadcast in the cell by receiving the PBCH from the BS. During the initial cell search, the UE can also monitor the DL channel status by receiving a downlink reference signal (DL RS).

[0065] After the initial cell search, the UE may acquire more detailed system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) corresponding to the PDCCH (S12).

[0066] Subsequently, in order to complete the connection to the BS, the UE may perform a random access procedure with the BS (S13 to S16). Specifically, the UE may transmit a preamble on a physical random access channel (PRACH) (S13), and may receive a PDCCH and a random access response (RAR) for the preamble on a PDSCH corresponding to the PDCCH (S14). The UE may then transmit a physical uplink shared channel (PUSCH) using the scheduling information in the RAR (S15), and perform a contention resolution procedure, including receiving a PDCCH and a PDSCH signal corresponding to the PDCCH (S16).

[0067] When the random access procedure is performed in two steps, steps S13 and S15 may be performed as one step (wherein message A is transmitted by the UE), and steps S14 and S16 may be performed as one step (wherein message B is transmitted by the BS).

[0068] After the above process, in the general UL / DL signal transmission process, the UE can receive PDCCH (S16) and / or PDSCH (S17) from the BS, and send a physical uplink shared channel (PUSCH) and / or a physical uplink control channel (PUCCH) (S18) to the BS. The control information sent by the UE to the BS is generally referred to as uplink control information (UCI). UCI includes hybrid automatic repeat and request acknowledgement / negative acknowledgement (HARQ-ACK / NACK), scheduling request (SR), channel state information (CSI), etc. CSI includes channel quality indicator (CQI), precoding matrix index (PMI), rank indication (RI), etc. Typically, UCI is sent on the PUCCH. However, if control information and data should be sent at the same time, the control information and data can be sent on the PUSCH. In addition, upon receiving a request / command from the network, the UE can send UCI on the PUSCH aperiodically.

[0069] Figure 2 Figure 1 shows the radio frame structure.

[0070] In NR, UL and DL transmissions are configured in frames. Each radio frame has a length of 10 milliseconds and is divided into two 5ms half-frames. Each half-frame is divided into five 1ms subframes. A subframe is divided into one or more time slots, and the number of time slots in a subframe depends on the subcarrier spacing (SCS). Depending on the cyclic prefix (CP), each time slot includes 12 or 14 OFDM (A) symbols. When a normal CP is used, each time slot includes 14 OFDM symbols. When an extended CP is used, each time slot includes 12 OFDM symbols. Symbols can include OFDM symbols (or CP-OFDM symbols) and SC-FDMA symbols (or discrete Fourier transform-spread OFDM (DFT-s-OFDM) symbols).

[0071] Table 1 exemplarily illustrates that the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary according to the SCS in the normal CP case.

[0072] [Table 1]

[0073] SCS(15*2^u) <![CDATA[N slot symb ]]> <![CDATA[N frame,u slot ]]> <![CDATA[N subframe,u slot ]]> 15KHz (u=0) 14 10 1 30KHz (u=1) 14 20 2 60KHz (u=2) 14 40 4 120KHz (u=3) 14 80 8 240KHz (u=4) 14 160 16

[0074] *N slot symb : The number of symbols in a time slot

[0075] *N frame,u slot : Number of time slots in a frame

[0076] *N subframe,u slot : Number of time slots in a subframe

[0077] Table 2 illustrates that the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary according to SCS in the case of extended CP.

[0078] [Table 2]

[0079] SCS(15*2^u) <![CDATA[N slot symb ]]> <![CDATA[N frame,u slot ]]> <![CDATA[N subframe,u slot ]]> 60KHz (u=2) 12 40 4

[0080] The frame structure is only an example, and the number of subframes, slots, and symbols in a frame can be changed in various ways. In the NR system, different OFDM(A) parameter sets (e.g., SCS, CP length, etc.) can be configured for multiple cells aggregated for one UE. Therefore, the (absolute time) duration of a time resource (e.g., a subframe, slot, or transmission time interval (TTI)) consisting of the same number of symbols (for convenience, referred to as a time unit (TU)) can be configured differently between aggregated cells.

[0081] In NR, various parameter sets (or SCSs) can be supported to support various fifth-generation (5G) services. For example, with an SCS of 15kHz, wide areas in traditional cellular bands can be supported, and with an SCS of 30kHz or 60kHz, dense urban areas, lower latency, and wide carrier bandwidths can be supported. With an SCS of 60kHz or higher, bandwidths greater than 24.25kHz can be supported to overcome phase noise.

[0082] The NR band can be defined by two types of frequency ranges (FR1 and FR2). FR1 and FR2 can be configured as described in Table 3 below. FR2 can be millimeter wave (mmW).

[0083] [Table 3]

[0084] Frequency range specification Corresponding frequency range Subcarrier spacing FR1 450MHz-7125MHz 15, 30, 60kHz FR2 24250MHz-52600MHz 60, 120, 240kHz

[0085] Figure 3 The diagram shows a resource grid over the duration of a time slot. A time slot includes multiple symbols in the time domain. For example, a time slot includes 14 symbols in the normal CP case and 12 symbols in the extended CP case. A carrier includes multiple subcarriers in the frequency domain. A resource block (RB) can be defined by multiple (e.g., 12) consecutive subcarriers in the frequency domain. A bandwidth part (BWP) can be defined by multiple consecutive (physical) RBs ((P)RBs) in the frequency domain and corresponds to a parameter set (e.g., SCS, CP length, etc.). A carrier can include up to N (e.g., 5) BWPs. Data communication can be carried out in active BWPs, and a UE can only activate one BWP. Each element in the resource grid can be referred to as a resource element (RE) to which a complex symbol can be mapped.

[0086] Figure 4 An exemplary mapping of physical channels in time slots is illustrated.

[0087] DL control channels, DL or UL data, and UL control channels may all be included in one time slot. For example, the first N symbols in a time slot (hereinafter referred to as the DL control region) may be used to transmit DL control channels, and the last M symbols in a time slot (hereinafter referred to as the UL control region) may be used to transmit UL control channels. N and M are integers equal to or greater than 0. The resource region (hereinafter referred to as the data region) between the DL control region and the UL control region may be used for DL ​​data transmission or UL data transmission. A time gap for DL ​​to UL or UL to DL switching may be defined between the control region and the data region. PDCCH may be transmitted in the DL control region, and PDSCH may be transmitted in the DL data region. Some symbols in a time slot when switching from DL to UL may be configured as time gaps.

[0088] Now, a detailed description will be given of the physical channels.

[0089] DL channel structure

[0090] The eNB transmits a relevant signal to the UE on a DL channel described later, and the UE receives a relevant signal from the eNB on the DL channel.

[0091] (1) Physical Downlink Shared Channel (PDSCH)

[0092] The PDSCH carries DL data (e.g., DL shared channel transport blocks (DL-SCH TBs)) and uses modulation schemes such as quadrature phase shift keying (QPSK), 16-ary quadrature amplitude modulation (16QAM), 64-ary QAM (64QAM), or 256-ary QAM (256QAM). TBs are encoded as codewords. The PDSCH can deliver up to two codewords. The codewords are individually subjected to scrambling and modulation mapping, and the modulation symbols from each codeword are mapped to one or more layers. An OFDM signal is generated by mapping each layer to a resource together with a DMRS, and the OFDM signal is transmitted through the corresponding antenna port.

[0093] (2) Physical Downlink Control Channel (PDCCH)

[0094] PDCCH delivers DCI. For example, PDCCH (i.e., DCI) can carry information about the transport format and resource allocation of the DL shared channel (DL-SCH), resource allocation information of the uplink shared channel (UL-SCH), paging information about the paging channel (PCH), system information about DL-SCH, information about resource allocation of higher-layer control messages (such as RAR sent on PDSCH), transmit power control commands, information about activation / release of configured scheduling, etc. DCI includes a cyclic redundancy check (CRC). Depending on the owner or use of the PDCCH, the CRC is masked with various identifiers (IDs) (e.g., radio network temporary identifier (RNTI)). For example, if the PDCCH is for a specific UE, the CRC is masked by the UE ID (e.g., cell RNTI (C-RNTI)). If the PDCCH is used for a paging message, the CRC is masked by the paging RNTI (P-RNTI). If the PDCCH is used for system information (e.g., system information block (SIB)), the CRC is masked by the system information RNTI (SI-RNTI). When the PDCCH is used for RAR, the CRC is masked by a random access RNTI (RA-RNTI).

[0095] The PDCCH uses a fixed modulation scheme (e.g., QPSK). A PDCCH consists of 1, 2, 4, 8, or 16 control channel elements (CCEs) depending on its aggregation level (AL). A CCE consists of 6 resource element groups (REGs), each of which is defined by one (P)RB by one OFDM symbol.

[0096] The PDCCH is transmitted in a control resource set (CORESET). A CORESET corresponds to a set of physical resources / parameters used to deliver PDCCH / DCI in a BWP. For example, a CORESET is defined as a set of REGs with a given parameter set (e.g., SCS, CP length, etc.). A CORESET can be configured by system information (e.g., Master Information Block (MIB)) or UE-specific higher layer signaling (e.g., RRC signaling). For example, the following parameters / information can be used to configure a CORESET, and multiple CORESETs can overlap with each other in the time / frequency domain.

[0097] -controlResourceSetId: indicates the ID of the CORESET.

[0098] -frequencyDomainResources: Indicates the frequency domain resources of the CORESET. The frequency domain resources are indicated by a bitmap, and each bit of the bitmap corresponds to an RB group (i.e., six consecutive RBs). For example, the most significant bit (MSB) of the bitmap corresponds to the first RB group of the BWP. The RB group corresponding to the bit set to 1 is allocated as the frequency domain resource of the CORESET.

[0099] Duration: Indicates the time region resource of the CORESET. It indicates the number of consecutive OFDMA symbols in the CORESET. For example, the duration is set to one of 1 to 3.

[0100] -cce-REG-MappingType: Indicates the CCE to REG mapping type. Both interleaved and non-interleaved types are supported.

[0101] -precoderGranularity: Indicates the precoder granularity in the frequency domain.

[0102] -tci-StatesPDCCH: Provides information indicating the Transmission Configuration Indication (TCI) state for PDCCH (e.g., TCI-StateID). The TCI state is used to provide a quasi-co-location relationship between (one or more) DL RSs in an RS set (TCI state) and the PDCCH DMRS port.

[0103] -tci-PresentInDCI: Indicates whether the TCI field is included in the DCI.

[0104] -pdcch-DMRS-ScramblingID: Provides information for initializing the PDCCH DMRS scrambling sequence.

[0105] To receive the PDCCH, the UE may monitor (e.g., blindly decode) a set of PDCCH candidates in a CORESET. A PDCCH candidate is a CCE(s) that the UE monitors for PDCCH reception / detection. PDCCH monitoring may be performed in one or more CORESETs in the active DL BWP on each active cell configured with PDCCH monitoring. The set of PDCCH candidates monitored by the UE is defined as a PDCCH search space (SS) set. The SS set may be a common search space (CSS) set or a UE-specific search space (USS) set.

[0106] Table 4 lists exemplary PDCCH SSs.

[0107] [Table 4]

[0108]

[0109] The SS set can be configured by system information (e.g., MIB) or UE-specific higher layer (e.g., RRC) signaling. S or fewer SS sets can be configured in each DL BWP of the serving cell. For example, the following parameters / information can be provided for each SS set. Each SS set can be associated with one CORESET, and each CORESET configuration can be associated with one or more SS sets. -searchSpaceId: Indicates the ID of the SS set.

[0110] -controlResourceSetId: Indicates the CORESET associated with the SS set.

[0111] - monitoringSlotPeriodicityAndOffset: indicates the PDCCH monitoring periodicity (in time slots) and the PDCCH monitoring offset (in time slots).

[0112] -monitoringSymbolsWithinSlot: Indicates the first OFDMA symbol(s) used for PDCCH monitoring in a slot configured with PDCCH monitoring. The OFDMA symbols are indicated by a bitmap, and each bit of the bitmap corresponds to an OFDM symbol in the slot. The MSB of the bitmap corresponds to the first OFDM symbol of the slot. The OFDMA symbol(s) corresponding to the bit(s) set to 1 correspond to the first symbol(s) of the CORESET in that slot.

[0113] -nrofCandidates: indicates the number of PDCCH candidates for each AL={1, 2, 4, 8, 16} (eg, one of 0, 1, 2, 3, 4, 5, 6, and 8).

[0114] -searchSpaceType: Indicates whether the SS type is CSS or USS.

[0115] -DCI format: indicates the DCI format of the PDCCH candidate.

[0116] The UE can monitor PDCCH candidates in one or more SS sets in a time slot based on the CORESET / SS set configuration. The timing (e.g., time / frequency resource) at which PDCCH candidates should be monitored is defined as a PDCCH (monitoring) opportunity. One or more PDCCH (monitoring) opportunities can be configured in a time slot.

[0117] Table 5 illustrates an exemplary DCI format transmitted on the PDCCH.

[0118] [Table 5]

[0119]

[0120] DCI format 0_0 can be used to schedule TB-based (or TB-level) PUSCH, and DCI format 0_1 ​​can be used to schedule TB-based (or TB-level) PUSCH or code block group (CBG) (or CBG level) based PUSCH. DCI format 1_0 can be used to schedule TB-based (or TB-level) PDSCH, and DCI format 1_1 can be used to schedule TB-based (or TB-level) PDSCH or CBG (or CBG level) based PDSCH (DL grant DCI). DCI format 0_0 / 0_1 can be referred to as UL grant DCI or UL scheduling information, and DCI format 1_0 / 1_1 can be referred to as DL grant DCI or DL ​​scheduling information. DCI format 2_0 is used to deliver dynamic slot format information (e.g., dynamic slot format indicator (SFI)) to the UE, and DCI format 2_1 is used to deliver DL preemption information to the UE. DCI format 2_0 and / or DCI format 2_1 can be delivered to a corresponding group of UEs on a group common PDCCH, which is a PDCCH for a group of UEs. DCI format 0_0 and DCI format 1_0 can be referred to as fallback DCI formats, while DCI format 0_1 ​​and DCI format 1_1 can be referred to as non-fallback DCI formats. In the fallback DCI format, the DCI size / field configuration remains the same regardless of the UE configuration. In contrast, the DCI size / field configuration varies in the non-fallback DCI format depending on the UE configuration.

[0121] UL channel structure

[0122] The UE transmits a relevant signal to the BS on a UL channel to be described later, and the BS receives the relevant signal from the UE through the UL channel to be described later.

[0123] (1) Physical Uplink Control Channel (PUCCH)

[0124] The PUCCH carries UCI, HARQ-ACK and / or Scheduling Request (SR), and is divided into a short PUCCH and a long PUCCH according to a PUCCH transmission length.

[0125] The UCI includes the following information.

[0126] -SR: Information used to request UL-SCH resources.

[0127] -HARQ-ACK: A response to a DL data packet (e.g., a codeword) on the PDSCH. HARQ-ACK indicates whether the DL data packet has been successfully received. In response to a single codeword, a 1-bit HARQ-ACK can be sent. In response to two codewords, a 2-bit HARQ-ACK can be sent. HARQ-ACK responses include positive ACK (abbreviated as ACK), negative ACK (NACK), discontinuous transmission (DTX), or NACK / DTX. The term HARQ-ACK can be used interchangeably with HARQ ACK / NACK and ACK / NACK.

[0128] -CSI: Feedback information for DL ​​channels. Feedback information related to Multiple Input Multiple Output (MIMO) includes RI and PMI.

[0129] Table 6 illustrates an exemplary PUCCH format. Based on PUCCH transmission duration, PUCCH formats can be divided into short PUCCH (formats 0 and 2) and long PUCCH (formats 1, 3, and 4).

[0130] [Table 6]

[0131]

[0132] PUCCH format 0 conveys up to 2 bits of UCI and is mapped in a sequence-based manner for transmission. Specifically, the UE sends a specific UCI to the BS by sending one of multiple sequences on the PUCCH of PUCCH format 0. Only when the UE sends a positive SR, the UE sends the PUCCH of PUCCH format 0 in the PUCCH resources used for the corresponding SR configuration. PUCCH format 1 conveys up to 2 bits of UCI in the time domain and spreads the modulation symbols of the UCI in the time domain with an orthogonal cover code (OCC) (which is configured differently depending on whether frequency hopping is performed). DMRS is transmitted with symbols that do not transmit modulation symbols (i.e., transmitted in time division multiplexing (TDM)).

[0133] PUCCH format 2 conveys more than 2 bits of UCI, and the modulation symbols of the DCI are sent in frequency division multiplexing (FDM) with the DMRS. The DMRS are located in symbols #1, #4, #7, and #10 of a given RB with a density of 1 / 3. A pseudo-noise (PN) sequence is used for the DMRS sequence. For the 2-symbol PUCCH format 2, frequency hopping can be activated.

[0134] PUCCH format 3 does not support UE multiplexing in the same PRBS and conveys more than 2 bits of UCI. In other words, the PUCCH resources of PUCCH format 3 do not include OCC. Modulation symbols and DMRS are sent in TDM.

[0135] PUCCH format 4 supports multiplexing of up to four UEs in the same PRBS and conveys more than two bits of UCI. In other words, the PUCCH resources of PUCCH format 3 include OCC. The modulation symbols and DMRS are sent in time-division multiplexing (TDM).

[0136] (2) Physical Uplink Shared Channel (PUSCH)

[0137] The PUSCH carries UL data (e.g., UL shared channel transport blocks (UL-SCH TBs)) and / or UL control information (UCI) and is transmitted based on a cyclic prefix-orthogonal frequency division multiplexing (CP-OFDM) waveform or a discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-s-OFDM) waveform. When transmitting the PUSCH based on a DFT-s-OFDM waveform, the UE transmits the PUSCH by applying transform precoding. For example, when transform precoding is not allowed (e.g., transform precoding is disabled), the UE may transmit the PUSCH based on a CP-OFDM waveform. When transform precoding is allowed (e.g., transform precoding is enabled), the UE may transmit the PUSCH based on a CP-OFDM waveform or a DFT-s-OFDM waveform. PUSCH transmissions may be dynamically scheduled by a UL grant in the DCI, or may be semi-statically scheduled based on higher layer (e.g., RRC) signaling (and / or Layer 1 (L1) signaling (e.g., PDCCH)) (configured grant). PUSCH transmission may be performed on a codebook basis or a non-codebook basis.

[0138] On the DL, the BS can dynamically allocate resources for DL ​​transmission to the UE through (one or more) PDCCHs (including DCI format 1_0 or DCI format 1_1). In addition, the BS can indicate to a specific UE through (one or more) PDCCHs (including DCI format 2_1) that some resources pre-scheduled for the UE have been preempted for signal transmission to another UE. In addition, the BS can configure the DL assignment period through higher layer signaling in a semi-persistent scheduling (SPS) scheme, and signal the activation / deactivation of the DL assignment configured by the PDCCH to provide the UE with a DL assignment for initial HARQ transmission. When retransmission for the initial HARQ transmission is required, the BS explicitly schedules the retransmission resources through the PDCCH. When a DCI-based DL assignment conflicts with an SPS-based DL assignment, the UE can give priority to the DCI-based DL assignment.

[0139] Similar to DL, for UL, the BS can dynamically allocate resources for UL transmission to the UE through (one or more) PDCCHs (including DCI format 0_0 or DCI format 0_1). In addition, the BS can allocate UL resources for initial HARQ transmission to the UE based on the configured grant (CG) method (similar to SPS). Although dynamic scheduling involves PDCCH for PUSCH transmission, the configured grant does not involve PDCCH for PUSCH transmission. However, the UL resources for retransmission are explicitly allocated by (one or more) PDCCHs. In this way, the operation of the BS to pre-configure UL resources without dynamic grant (DG) (for example, by scheduling UL grant of DCI) is called "CG". Two types of CG are defined.

[0140] - Type 1: UL grants with a predetermined period are provided by higher layer signaling (without L1 signaling).

[0141] -Type 2: The period of UL grant is configured by higher layer signaling, and activation / deactivation of CG is signaled by PDCCH to provide UL grant.

[0142] Figure 5 FIGURE 1 illustrates an exemplary UL transmission operation of a UE. The UE may be based on DG( Figure 5 (a)) or based on CG( Figure 5 (b)) to send the expected packet.

[0143] Resources for CG can be shared among multiple UEs. UL signal transmission based on the CG from each UE can be identified by time / frequency resources and RS parameters (e.g., different cyclic shifts, etc.). Therefore, when a UE fails to transmit an UL signal due to a signal collision, the BS can identify the UE and explicitly send a retransmission permission for the corresponding TB to the UE.

[0144] The CG supports K repetitions, including an initial transmission, for the same TB. Based on the resources used for the initial transmission, the same HARQ process ID is determined for the K repetitions of the UL signal. The redundancy version (RV) of the K repetitions of the TB has one of the patterns {0, 2, 3, 1}, {0, 3, 0, 3}, and {0, 0, 0, 0}.

[0145] Figure 6 An exemplary CG-based repeated transmission is illustrated.

[0146] The UE performs repeated transmissions until one of the following conditions is met:

[0147] - Successfully received UL grant for the same TB;

[0148] -TB is repeated up to K times; and

[0149] - (In option 2) the end time of period P is reached.

[0150] Similar to Licensed Assisted Access (LAA) in legacy 3GPP LTE systems, the use of unlicensed bands for cellular communications is also being considered in 3GPP NR systems. Unlike LAA, standalone (SA) operation is targeted in NR cells operating in unlicensed bands (hereinafter referred to as NR unlicensed cells (Ucells)). For example, PUCCH, PUSCH, and PRACH transmissions can be supported in NR Ucells.

[0151] On the LAA UL, with the introduction of asynchronous HARQ processes, there is no additional channel, such as the Physical HARQ Indicator Channel (PHICH), for indicating HARQ-ACK information for PUSCH to the UE. Therefore, accurate HARQ-ACK information may not be used to adjust the contention window (CW) size in the UL LBT process. In the UL LBT process, when a UL grant is received in the nth subframe, the first subframe of the most recent UL transmission burst before the (n-3)th subframe has been configured as a reference subframe, and the CW size has been adjusted based on the new data indicator (NDI) for the HARQ process ID corresponding to the reference subframe. That is, when the BS switches the NDI or instructs retransmission of one or more TBs according to one or more transport blocks (TBs), a method has been introduced: assuming that the transmission of the PUSCH fails in the reference subframe due to a collision with other signals, the CW size is increased to the next maximum CW size of the currently applied CW size in a set of pre-agreed CW sizes, or assuming that the PUSCH in the reference subframe has been successfully transmitted without a collision with other signals, the CW size is initialized to the minimum value (e.g., CWmin).

[0152] In an NR system to which various embodiments of the present disclosure are applicable, each component carrier (CC) may be allocated / supported up to 400 MHz. When a UE operating in such a wideband CC always turns on the radio frequency (RF) module in the entire CC, the battery consumption of the UE may increase.

[0153] Alternatively, considering various use cases (e.g., eMBB, URLLC, mMTC, etc.) operating within a single wideband CC, different parameter sets (e.g., SCS) can be supported for each frequency band within the CC.

[0154] Alternatively, each UE may have a different maximum bandwidth capability.

[0155] In this regard, the BS may indicate to the UE to operate only in a portion of the bandwidth of the wideband CC instead of the full bandwidth. The portion of the bandwidth may be defined as a bandwidth part (BWP).

[0156] A BWP may be a subset of consecutive RBs on the frequency axis. One BWP may correspond to one parameter set (eg, SCS, CP length, slot / mini-slot duration, etc.).

[0157] The BS can configure multiple BWPs in a CC configured for a UE. For example, the BS can configure a BWP occupying a relatively small frequency region in the PDCCH monitoring time slot and schedule the PDSCH indicated (or scheduled) by the PDCCH in a larger BWP. Alternatively, when UEs are concentrated on a specific BWP, the BS can configure another BWP for some UEs for load balancing. Alternatively, considering frequency domain inter-cell interference cancellation between adjacent cells, the BS can exclude some spectrum from the total bandwidth and configure BWPs on both sides of the cell in the same time slot.

[0158] The BS may configure at least one DL / UL BWP for a UE associated with a wideband CC, activate at least one of the configured DL / UL BWP(s) at a specific point in time (via L1 signaling (e.g., DCI), MAC signaling, or RRC signaling), and instruct (via L1 signaling, MAC signaling, or RRC signaling) switching to another configured DL / UL BWP. Furthermore, upon expiration of a timer value (e.g., a BWP inactivity timer value), the UE may switch to the predetermined DL / UL BWP. The activated DL / UL BWP may be referred to as an active DL / UL BWP. During initial access or before RRC connection establishment, the UE may not receive a configuration for a DL / UL BWP from the BS. The DL / UL BWP assumed by the UE in this case is defined as the initial active DL / UL BWP.

[0159] Figure 7 An exemplary wireless communication system supporting unlicensed bands suitable for use with the present disclosure is illustrated.

[0160] In the following description, a cell operating in an authorized band (L-band) is defined as an L cell, and a carrier of the L cell is defined as a (DL / UL) LCC. A cell operating in an unlicensed band (U-band) is defined as a U cell, and a carrier of the U cell is defined as a (DL / UL) UCC. A cell's carrier / carrier frequency may refer to the cell's operating frequency (e.g., center frequency). A cell / carrier (e.g., CC) is generally referred to as a cell.

[0161] When the BS and UE send and receive signals on the LCC and UCC of carrier aggregation, such as Figure 7As shown in (a), LCC and UCC can be configured as primary CC (PCC) and secondary CC (SCC) respectively. BS and UE can send and receive signals on one UCC or on multiple carrier aggregation UCCs, as shown in Figure 7 (b) In other words, the BS and UE can send and receive signals only on (one or more) UCCs without using any LCCs. For SA operation, PRACH, PUCCH, PUSCH, and SRS transmission can be supported on the UCell.

[0162] The signal transmission and reception operations in the unlicensed band as described in this disclosure can be applied to the above-mentioned deployment scenarios (unless otherwise specified).

[0163] Unless otherwise stated, the following definitions apply to the following terms used in this disclosure.

[0164] - Channel: A carrier or a portion of a carrier consisting of a set of consecutive RBs, where a channel access procedure (CAP) is performed in the shared spectrum.

[0165] - Channel Access Procedure (CAP): A procedure for evaluating channel availability based on sensing before signal transmission in order to determine whether (one or more) other communication nodes are using the channel. The basic sensing unit is a time duration T sl = 9us sensing time slot. The BS or UE senses the time slot during the sensing time slot duration. When the power detected in at least 4us within the sensing time slot duration is less than the energy detection threshold X thresh The sensing time slot duration is T sl is considered idle. Otherwise, the sensing time slot duration is T sl Considered busy. CAP can also be called Listen Before Talk (LBT).

[0166] - Channel occupancy: Transmission(s) on the channel(s) from the BS / UE after the CAP.

[0167] - Channel Occupancy Time (COT): The total time that a BS / UE and any (one or more) BS / UEs sharing the channel perform (one or more) transmissions on the channel after the CAP. With respect to COT determination, if a transmission gap is less than or equal to 25us, the gap duration can be counted in the COT.

[0168] The COT may be shared for transmission between the BS and the corresponding UE(s).

[0169] Specifically, sharing the UE-initiated COT with the BS may refer to an operation in which the UE assigns a portion of the channel occupied by random backoff-based LBT (e.g., Category 3 (Cat-3) LBT or Category 4 (Cat-4) LBT) to the BS, and when LBT is performed without random backoff (e.g., Category 1 (Cat-1) LBT or Category 2 (Cat-2) LBT) using a timing gap occurring before DL transmission starting from the UE's UL transmission end timing, after successfully confirming that the channel is idle through LBT, the BS performs DL transmission using the remaining COT of the UE.

[0170] Meanwhile, sharing the gNB-initiated COT with the UE may refer to an operation in which the BS assigns a portion of a channel occupied by LBT based on random backoff (e.g., Cat-3 LBT or Cat-4 LBT) to the UE, and when, after performing LBT (e.g., Cat-1 LBT or Cat-2 LBT) without random backoff using a timing gap occurring before UL transmission starting from the DL transmission end timing of the BS, the UE performs UL transmission using the remaining COT of the BS when the channel is idle after successful confirmation through LBT.

[0171] -DL transmission burst: A set of transmissions from a BS without any gaps greater than 16 us. Transmissions from a BS separated by gaps greater than 16 us are considered separate DL transmission bursts. The BS may perform (one or more) transmissions after a gap without sensing channel availability within a DL transmission burst.

[0172] -UL transmission burst: A set of transmissions from a UE without any gaps greater than 16 us. Transmissions from a UE separated by gaps greater than 16 us are considered separate UL transmission bursts. The UE may perform (one or more) transmissions after a gap without sensing channel availability within a DL transmission burst.

[0173] -Discovery burst: A DL transmission burst including a set of (one or more) signals and / or (one or more) channels that are confined within a window and associated with a duty cycle. The discovery burst may include (one or more) transmissions initiated by the BS, including PSS, SSS, and cell-specific RS (CRS), and further including non-zero power CSI-RS. In an NR system, the discovery burst may include (one or more) transmissions initiated by the BS, which include at least SS / PBCH blocks and further include a CORESET of a PDCCH for scheduling a PDSCH carrying SIB1, a PDSCH carrying SIB1, and / or non-zero power CSI-RS.

[0174] Figure 8An exemplary method of occupying resources in an unlicensed band is illustrated.

[0175] refer to Figure 8 , a communication node (e.g., BS or UE) operating in an unlicensed band should determine whether (one or more) other communication nodes are using a channel before signal transmission. For this purpose, the communication node may perform CAP to access (one or more) channels on which (one or more) transmissions are to be performed in the unlicensed band. CAP may be performed based on sensing. For example, a communication node may determine whether (one or more) other communication nodes are transmitting signals on (one or more) channels by carrier sensing (CS) before signal transmission. Determining that (one or more) other communication nodes are not transmitting signals is defined as confirming a clear channel assessment (CCA). In the presence of a CCA threshold (e.g., X) that has been predefined or configured by higher layer (e.g., RRC) signaling, the communication node may determine whether (one or more) other communication nodes are transmitting signals on (one or more) channels. thresh ), when energy above the CCA threshold is detected in the channel, the communication node may determine that the channel is busy. Otherwise, the communication node may determine that the channel is idle. When the channel is determined to be idle, the communication node may begin transmitting signals in the unlicensed band. CAP can be replaced by LBT.

[0176] Table 7 describes exemplary CAPs supported in NR-U.

[0177] [Table 7]

[0178]

[0179] In a wireless communication system supporting unlicensed bands, a cell (or carrier (e.g., CC)) or BWP configured for a UE may be broadband with a larger bandwidth (BW) than conventional LTE. However, the BW of a CCA requiring independent LBT operation may be limited according to regulations. A subband (SB) in which LBT is performed separately is defined as an LBT-SB. Multiple LBT-SBs may then be included in one broadband cell / BWP. The RB set included in the LBT-SB may be configured through higher layer (e.g., RRC) signaling. Therefore, based on (i) the BW of the cell / BWP and (ii) the RB set allocation information, one or more LBT-SBs may be included in one cell / BWP. Multiple LBT-SBs may be included in the BWP of a cell (or carrier). The LBT-SB may be, for example, a 20-MHz frequency band. The LBT-SB may include multiple consecutive (P)RBs in the frequency domain and may therefore be referred to as a (P)RB set.

[0180] In Europe, two LBT operations are defined: frame-based equipment (FBE) and load-based equipment (LBE). In FBE, a fixed frame consists of a channel occupation time (e.g., 1 to 10 ms) and an idle period corresponding to at least 5% of the occupied channel occupation time. The channel occupation time is the time period during which the communication node can continue to transmit during the successful channel access, and CCA is defined as an operation of observing the channel during the CCA time slot (at least 20 us) at the end of the idle period. The communication node periodically performs CCA based on the fixed frame. When the channel is not occupied, the communication node transmits during the channel occupation time, and when the channel is occupied, the communication node postpones transmission and waits until the CCA time slot in the next period.

[0181] In LBE, the communication node can set q∈{4, 5, ..., 32} and then perform CCA within one CCA slot. When the channel is not occupied in the first CCA slot, the communication node can secure a time period of up to (13 / 32)q ms and send data during this time period. When the channel is occupied in the first CCA slot, the communication node randomly selects N∈{1, 2, ..., q}, stores the selected value as the initial value, and then senses the channel state based on the CCA slot. Each time the channel is not occupied in the CCA slot, the communication node decrements the stored counter value by 1. When the counter value reaches 0, the communication node can secure a time period of up to (13 / 32)q ms and send data.

[0182] The eNB / gNB or UE of the LTE / NR system should also perform LBT for signal transmission in the unlicensed band (referred to as the U-band for convenience). When the eNB or UE of the LTE / NR system transmits a signal, other communication nodes such as Wi-Fi nodes should also perform LBT so as not to interfere with the transmission of the eNB or UE. For example, in the Wi-Fi standard (801.11ac), the CCA threshold is defined as -62dBm for non-Wi-Fi signals and -82dBm for Wi-Fi signals. For example, when a non-Wi-Fi signal is received by a station (STA) or access point (AP) at a power greater than -62dBm, the STA or AP does not transmit other signals to avoid causing interference.

[0183] The UE performs Type 1 or Type 2 CAP for UL signal transmission in the unlicensed band. Generally, the UE can perform the CAP (e.g., Type 1 or Type 2) configured by the BS for UL signal transmission. For example, CAP type indication information can be included in the UL grant (e.g., DCI format 0_0 or DCI format 0_1) that schedules PUSCH transmission.

[0184] In a Type 1 UL CAP, the length of the time period spanned by the sensing slots sensed as idle before the transmission(s) is random.The Type 1 UL CAP may be applied to the following transmissions.

[0185] - PUSCH / SRS transmission(s) scheduled and / or configured by the BS

[0186] - PUCCH transmission(s) scheduled and / or configured by the BS

[0187] - Transmission(s) associated with the Random Access Procedure (RAP)

[0188] Figure 9 The diagram illustrates a Type 1 CAP in a channel access procedure of a UE for UL / DL signal transmission in the U-band applicable to the present disclosure.

[0189] First, refer to Figure 9 Describe UL signal transmission in the U-band.

[0190] The UE can postpone for a duration T d , senses whether the channel is idle during the sensing time slot duration in . After the counter N is decremented to 0, the UE may perform a transmission (S934). According to the following process, the counter N is adjusted by sensing the channel during the additional time slot duration (one or more).

[0191] Step 1) Set N=N init , where N init is evenly distributed between 0 and CW P and go to step 4 (S920).

[0192] Step 2) If N>0 and the UE chooses to decrement the counter, then N=N-1 is set (S940).

[0193] Step 3) Sense the channel during the additional time slot duration, and if the additional time slot duration is idle (Y), go to step 4. Otherwise (N), go to step 5 (S950).

[0194] Step 4) If N=0 (Y) (S930), stop CAP (S932). Otherwise (N), go to step 2.

[0195] Step 5) Sense the channel until the additional delay duration T d Busy sensing time slot or additional delay duration T d All time slots of are sensed as idle (S960).

[0196] Step 6) If the additional delay duration T dIf the channel is sensed to be idle during all time slots of the channel (Y), go to step 4. Otherwise (N), go to step 5 (S970).

[0197] Table 8 illustrates the m applied to CAP P , minimum CW, maximum CW, maximum channel occupancy time (MCOT) and allowed CW size vary according to the channel access priority level.

[0198] [Table 8]

[0199]

[0200] Delay duration T d Including followed by m p The duration of consecutive time slots is T f (16us), where each time slot lasts for T sl is 9us, and T f The sensing time slot duration T is included at the beginning of the 16-us duration sl .CW Wmin,p <=CW p <=CW max,p .CW p Set to CW min,p , and can be updated (CW size update) based on explicit / implicit reception response to the previous UL burst (e.g., PUSCH) before step 1. p Can be initialized to CW based on explicit / implicit reception response to previous UL burst min,p , may be increased to the next higher allowed value, or may be maintained at the existing value.

[0201] In a Type 2 UL CAP, the length of the time period spanned by the sensing slot that is sensed as idle before (one or more) transmissions is deterministic. Type 2 UL CAPs are classified into Type 2A UL CAP, Type 2B UL CAP, and Type 2C UL CAP. In a Type 2A UL CAP, the UE may sense idle time slots for at least the sensing duration T short_dl The signal is sent immediately after the channel is sensed to be idle during (=25us). short_DL It includes the duration Tf (=16us) and the duration of a subsequent sensing slot. In Type 2A UL CAP, T f In a Type 2B UL CAP, the UE may select a sensing slot of duration T at the beginning of the sensing slot. f The signal is sent immediately after the channel is sensed as idle during the (=16us) period. In Type 2B UL CAP, Tf The sensing slot in the last 9us of the duration is included. In Type 2C UL CAP, the UE does not sense the channel before transmission.

[0202] To allow a UE to transmit UL data in the unlicensed band, the BS must succeed in LBT operation to send a UL grant in the unlicensed band, and the UE must also succeed in LBT operation to send UL data. That is, the UE can only attempt UL data transmission if both the BS and the UE succeed in their LBT operations. Furthermore, because there is a delay of at least 4 milliseconds between the UL grant and scheduled UL data in the LTE system, earlier access from another transmitting node coexisting in the unlicensed band during this period can postpone the UE's scheduled UL data transmission. In this context, methods for improving the efficiency of UL data transmission in the unlicensed band are being discussed.

[0203] In order to support UL transmission with relatively high reliability and relatively low time delay, NR also supports CG type 1 and CG type 2, in which the BS pre-configures time, frequency and coding resources for the UE through higher layer signaling (e.g., RRC signaling) or both higher layer signaling and L1 signaling (e.g., DCI). In the absence of a UL grant received from the BS, the UE can perform UL transmission in resources configured with type 1 or type 2. In type 1, the periodicity of the CG, the offset from SFN=0, the time / frequency resource allocation, the number of repetitions, the DMRS parameters, the MCS / TB size (TBS), the power control parameters, etc. are all configured only by higher layer signaling such as RRC signaling, without L1 signaling. Type 2 is a scheme in which the periodicity and power control parameters of the CG are configured by higher layer signaling such as RRC signaling, and information about the remaining resources (e.g., the offset of the initial transmission timing, the time / frequency resource allocation, the DMRS parameters and the MCS / TBS) are indicated by activating DCI as L1 signaling.

[0204] The biggest difference between the autonomous uplink (AUL) of LTE LAA and the CG of NR is the HARQ-ACK feedback transmission method for the PUSCH transmitted by the UE without receiving a UL grant and the presence or absence of UCI transmitted together with the PUSCH. Although the HARQ process is determined by the equation of the symbol index, symbol period and number of HARQ processes in the CG of NR, explicit HARQ-ACK feedback information is transmitted in the AUL downlink feedback information (AUL-DFI) in LTE LAA. In addition, in LTE LAA, whenever AUL PUSCH transmission is performed, UCI including information such as HARQ ID, NDI and RV is also transmitted in the AUL UCI. In the case of NR's CG, the BS identifies the UE by the time / frequency resources and DMRS resources used for PUSCH transmission, while in the case of LTE LAA, the BS identifies the UE by the UE ID explicitly included in the AUL UCI transmitted together with the PUSCH and DMRS resources.

[0205] Now, refer to Figure 9 Describe DL signal transmission in U-band.

[0206] The BS may perform one of the following U-band access procedures (eg, Channel Access Procedure (CAP)) to transmit a DL signal in the U-band.

[0207] (1) Type 1 DL CAP method

[0208] In a Type 1 DL CAP, the length of the duration spanned by the sensing slots that are sensed as idle before the transmission(s) is random. Type 1 DL CAP may be applied to the following transmissions:

[0209] - a transmission(s) initiated by the BS comprising (i) a unicast PDSCH with user plane data, or (ii) a unicast PDSCH with user plane data and a unicast PDCCH scheduling user plane data; or

[0210] - Transmission(s) initiated by the BS, comprising (i) only a discovery burst, or (ii) a discovery burst multiplexed with non-unicast information.

[0211] refer to Figure 9 , the BS may first sense whether the channel is idle during the sensing time slot duration of the postponed duration Td. Next, if the counter N is decremented to 0, the transmission may be performed (S934). According to the following process, the counter N is adjusted by sensing the channel during (one or more) additional time slot durations.

[0212] Step 1) Set N=Ninit, where Ninit is a random number uniformly distributed between 0 and CWp, and go to step 4 (S920).

[0213] Step 2) If N>0 and the BS chooses to decrement the counter, it sets N=N-1 (S940).

[0214] Step 3) Sense the channel during the additional time slot duration, and if the additional time slot duration is idle (Y), go to step 4. Otherwise (N), go to step 5 (S950).

[0215] Step 4) If N=0 (Y), stop CAP (S1232). Otherwise (N), go to step 2 (S930).

[0216] Step 5) The channel is sensed until a busy sensing slot is detected within the additional deferral duration Td or all slots of the additional deferral duration Td are sensed as idle (S960).

[0217] Step 6) If the channel is sensed to be idle during all time slots of the additional deferral duration Td (Y), go to step 4. Otherwise (N), go to step 5 (S970).

[0218] Table 9 illustrates that mp, minimum CW, maximum CW, MCOT, and allowed CW size applied to CAP vary according to channel access priority level.

[0219] [Table 9]

[0220]

[0221] The deferral duration Td includes a duration Tf (16 μs) followed by mp consecutive sensing time slot durations, wherein each sensing time slot duration Tsl is 9 μs, and Tf includes the sensing time slot duration Tsl at which the 16 μs duration begins.

[0222] CWmin,p<=CWp<=CWmax,p. CWp is set to CWmin,p and may be updated based on HARQ-ACK feedback (e.g., the ratio of ACK signals or NACK signals) for the previous DL burst (e.g., PDSCH) before step 1 (CW size update). For example, CWp may be initialized to CWmin,p based on HARQ-ACK feedback for the previous DL burst, may be increased to the next highest allowed value, or may be maintained at the existing value.

[0223] (2) Type 2DL CAP method

[0224] In a Type 2 DL CAP, the length of the duration spanned by the timeslots sensed as idle prior to transmission(s) is sensed deterministically.Type 2 DL CAPs are classified into Type 2A DL CAP, Type 2B DL ​​CAP, and Type 2C DL CAP.

[0225] Type 2A DL CAP can be applied to the following transmissions. In Type 2A DL CAP, the BS can send a signal immediately after sensing that the channel is idle during at least the sensing duration Tshort_dl = 25 μs. Tshort_dl includes the duration Tf (= 16 μs) and the duration of a subsequent sensing slot. Tf includes the sensing slot at the beginning of the duration.

[0226] - a transmission(s) initiated by the BS, comprising (i) only a discovery burst, or (ii) a discovery burst multiplexed with non-unicast information, or

[0227] - Within the shared channel occupancy, the BS's transmission(s) are spaced 25 μs after the UE's transmission(s).

[0228] Type 2B DL ​​CAP applies to (one or more) transmissions performed by the BS within the shared channel occupation period and after a gap of 16 μs from the UE's (one or more) transmissions. In Type 2B DL ​​CAP, the BS can send a signal immediately after sensing that the channel is idle during Tf = 16 μs. Tf includes the sensing time slot within the last 9 μs of the duration. Type 2C DL CAP applies to (one or more) transmissions performed by the BS within the shared channel occupation period and after a gap of 16 μs from the UE's (one or more) transmissions. In Type 2C DL CAP, the BS does not sense the channel before performing a transmission.

[0229] In a wireless communication system supporting U-band, one cell (or carrier (e.g., CC)) or BWP configured for a UE may consist of a broadband with a larger BW than in conventional LTE. However, according to regulations, the BW requiring CCA based on independent LBT operation may be restricted. If a subband (SB) in which LBT is performed separately is defined as an LBT-SB, multiple LBT-SBs may be included in one broadband cell / BWP. The RB set constituting the LBT-SB may be configured through higher layer (e.g., RRC) signaling. Therefore, based on (i) the BW of the cell / BWP and (ii) the RB set allocation information, one or more LBT-SBs may be included in one cell / BWP.

[0230] Figure 10 The diagram shows that a plurality of LBT-SBs are included in the U-band.

[0231] refer to Figure 10 , multiple LBT-SBs may be included in the BWP of a cell (or carrier). The LBT-SB may be, for example, a 20-MHz frequency band. The LBT-SB may include multiple consecutive (P)RBs in the frequency domain and may therefore be referred to as a (P)RB set. Although not shown, a guard band (GB) may be included between the LBT-SBs. Therefore, the BWP can be configured in the form of {LBT-SB#0 (RB set #0) + GB#0 + LBT-SB#1 (RB set #1 + GB#1) + ... + LBT-SB#(k-1) (RB set (#k-1))}. For convenience, the LBT-SB / RB index may be configured / defined to increase as the frequency band becomes higher starting from the low frequency band.

[0232] In NR systems, a massive multiple-input multiple-output (MIMO) environment in which the number of transmit / receive (Tx / Rx) antennas is significantly increased can be considered. That is, when considering a massive MIMO environment, the number of Tx / Rx antennas can be increased to tens or hundreds. NR systems support communications in frequency bands above 6 GHz (i.e., millimeter bands). However, the millimeter band is characterized by a frequency characteristic in which the signal attenuates very quickly depending on the distance due to the use of too high a frequency band. Therefore, in NR systems operating at 6 GHz or above, beamforming (BF) is considered, in which a signal is sent with concentrated energy in a specific direction rather than omnidirectionally to compensate for the rapid propagation attenuation. Therefore, for the purpose of improving performance, flexible resource allocation, and ease of frequency-based beam steering in massive MIMO environments, a hybrid BF is required that combines analog BF and digital BF according to the position of applying the BF weight vector / precoding vector.

[0233] Figure 11 is a block diagram illustrating an exemplary transmitter and receiver for hybrid BF.

[0234] In order to form a narrow beam in the millimeter frequency band, the BF method is mainly considered, in which the BS or UE sends the same signal through multiple antennas by applying an appropriate phase difference to the antenna and thus increasing the energy only in a specific direction. This BF method includes a digital BF for generating a phase difference for a digital baseband signal, an analog BF for generating a phase difference by using a time delay (i.e., a cyclic shift) to modulate an analog signal, and a hybrid BF with a combination of digital BF and analog beamforming. Using a radio frequency (RF) unit (or transceiver unit (TXRU)) for antenna elements to control transmission power and phase control based on antenna elements enables independent BF to be implemented for each frequency resource. However, installing TXRU in all approximately 100 antenna elements is not feasible in terms of cost. That is, a large number of antennas are required to compensate for the rapid propagation attenuation in millimeter frequencies, and digital BF requires as many RF components (e.g., digital-to-analog converters (DACs), mixers, power amplifiers, and linear amplifiers) as the number of antennas. Therefore, implementing digital BF in the millimeter frequency band increases the price of communication equipment. Therefore, when a large number of antennas are required, as in the case of millimeter bands, consider analog BF or hybrid BF. In analog BF, multiple antenna elements are mapped to a single TXRU, and the beam direction is controlled by an analog phase shifter. Because only one beam direction is generated over the entire frequency band in analog BF, frequency selective BF may not be achieved using analog BF. Hybrid BF is an intermediate form between digital BF and analog BF, using B RF units with fewer than Q antenna elements. In hybrid BF, the number of beam directions available for simultaneous transmission is limited to B or less, depending on how the B RF units and Q antenna elements are connected.

[0235] Beam Management (BM)

[0236] BM refers to a series of processes for acquiring and maintaining a set of BS beams (transmission and reception point (TRP) beams) and / or a set of UE beams that can be used for DL ​​and UL transmission / reception. BM may include the following processes and terms.

[0237] -Beamformation: The operation by which a BS or UE measures the characteristics of a received beamformed signal

[0238] -Beam determination: The operation by which the BS or UE selects its Tx / Rx beam

[0239] -Beam scanning: Operation that covers the spatial domain by using Tx and / or Rx beams at prescribed time intervals according to a predetermined method

[0240] -Beam reporting: Operation in which the UE reports information about a beamformed signal based on beam measurement

[0241] The BM process can be divided into (1) a DL BM process using SSB or CSI-RS and (2) a UL BM process using SRS. In addition, each BM process can include Tx beam scanning for determining a Tx beam and Rx beam scanning for determining an Rx beam.

[0242] The DL BM process may include (1) transmission of beamformed DL RS (eg, CSI-RS or SSB) from the BS and (2) beam reporting from the UE.

[0243] The beam report may include (one or more) preferred DL RS IDs and (one or more) reference signal received powers (RSRPs) corresponding to (one or more) preferred DL RS IDs. The DL RS ID may be a SSB resource indicator (SSBRI) or a CSI-RS resource indicator (CRI).

[0244] Figure 12 is a diagram illustrating an exemplary BF using SSB and CSI-RS.

[0245] refer to Figure 12 , SSB beams and CSI-RS beams can be used for beam measurement. The measurement metric is RSRP per resource / block. SSB can be used for coarse beam measurement, while CSI-RS can be used for fine beam measurement. SSB can be used for both Tx beam scanning and Rx beam scanning. SSB-based Rx beam scanning can be performed by attempting to receive SSBs for the same SSBRI while changing the Rx beam across multiple SSB bursts at the UE. An SS burst includes one or more SSBs, and an SS burst set includes one or more SSB bursts.

[0246] 1. DL BM using SSB

[0247] Figure 13 is a diagram illustrating a signal flow of an exemplary DL BM procedure using SSB.

[0248] During CSI / beam configuration in RRC_CONNECTED mode, SSB-based beam reporting is configured.

[0249] -The UE receives a CSI-ResourceConfig information element (IE) including a CSI-SSB-ResourceSetList of SSB resources for BM from the BS (S1310). The RRC parameter CSI-SSB-ResourceSetList is a list of SSB resources used for BM and reported in one resource set. The SSB resource set can be configured as {SSBx1, SSBx2, SSBx3, SSBx4}. The SSB index can range from 0 to 63.

[0250] -The UE receives a signal in SSB resources from the BS based on the CSI-SSB-ResourceSetList (S1320).

[0251] -When CSI-RS reportConfig related to SSBRI and RSRP reporting has been configured, the UE reports the best SSBRI and the RSRP corresponding to the best SSBRI to the BS (S1330). For example, when reportQuantity in the CSI-RS reportConfig IE is set to "ssb-Index-RSRP", the UE reports the best SSBRI and the RSRP corresponding to the best SSBRI to the BS.

[0252] When CSI-RS resources are configured in (one or more) OFDM symbols carrying SSBs and "QCL-Type D" is applicable to the CSI-RS resources and SSBs, the UE can assume that the CSI-RS and SSBs are quasi-co-located (QCLed) from the perspective of "QCL-Type D". QCL-Type D can refer to a QCL antenna port from the perspective of spatial Rx parameters. When the UE receives signals from multiple DL antenna ports in a QCL-Type D relationship, the UE can apply the same Rx beam to the signals.

[0253] 2. DL BM using CSI-RS

[0254] CSI-RS is used for the following purposes: i) when Repetition is configured for a specific CSI-RS resource set and TRS_info is not configured, CSI-RS is used for BM; ii) when Repetition is not configured for a specific CSI-RS resource set and TRS_info is configured, CSI-RS is used for tracking reference signal (TRS); and iii) when either Repetition or TRS_info is configured for a specific CSI-RS resource set, CSI-RS is used for CSI acquisition.

[0255] When (RRC parameter) Repetition is set to "on", this is related to the UE's Rx beam scanning process. When Repetition is set to "on", when the UE is configured with an NZP-CSI-RS-ResourceSet, the UE can assume that the signals in at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet are sent through the same DL spatial domain filter. That is, at least one CSI-RS resource within the NZP-CSI-RS-ResourceSet is sent on the same Tx beam. The signals in at least one CSI-RS resource within the NZP-CSI-RS-ResourceSet can be sent in different OFDM symbols.

[0256] In contrast, when Repetition is set to "off," this is related to the BS's Tx beam scanning process. When Repetition is set to "off," the UE does not assume that the signals in at least one CSI-RS resource within the NZP-CSI-RS-ResourceSet are transmitted using the same DL spatial domain filter. That is, the signals in at least one CSI-RS resource within the NZP-CSI-RS-ResourceSet are transmitted on different Tx beams. Figure 12 Another exemplary DL BM procedure using CSI-RS is illustrated.

[0257] Figure 14 (a) illustrates the UE’s Rx beam refinement process, and Figure 14 (b) illustrates the BS's Tx beam scanning process. Figure 14 (a) is used when Repetition is set to "On", and Figure 14 (b) For use when Repetition is set to "Off".

[0258] refer to Figure 14 (a) and Figure 15 (a), the Rx beam determination process of the UE will be described below.

[0259] Figure 15 (a) is a diagram illustrating a signal flow of an exemplary Rx beam determination process for a UE.

[0260] - The UE receives the NZP CSI-RS resource set IE including the RRC parameter "Repetition" from the BS through RRC signaling (S1510). Here, the RRC parameter "Repetition" is set to "On".

[0261] - The UE repeatedly receives signals in (one or more) resources of a CSI-RS resource set in which the RRC parameter "Repetition" is set to "on" on the same Tx beam (or DL ​​spatial domain Tx filter) of the BS in different OFDM symbols (S1520).

[0262] -UE determines its Rx beam (S1530).

[0263] -UE skips CSI reporting (S1540). That is, when the RRC parameter "Repetition" is set to "on", the UE can skip CSI reporting.

[0264] refer to Figure 14 (b) and Figure 15 (b), the Tx beam determination process of the BS will be described below.

[0265] Figure 15 (b) is a diagram illustrating an exemplary Tx beam determination process of a BS.

[0266] - The UE receives the NZP CSI-RS resource set IE including the RRC parameter "Repetition" from the BS through RRC signaling (S1550). When the RRC parameter "Repetition" is set to "off", this is related to the Tx beam scanning process of the BS.

[0267] - The UE receives signals in the resource(s) of the CSI-RS resource set in which the RRC parameter "Repetition" is set to "off" on different Tx beams (or DL ​​spatial domain Tx filters) of the BS (S1560).

[0268] -The UE selects (or determines) the best beam (S1570).

[0269] - The UE reports the ID of the selected beam (eg, CRI) and related quality information (eg, RSRP) to the BS (S1580). That is, when CSI-RS is transmitted for BM, the UE reports CRI and RSRP corresponding to the CRI.

[0270] Figure 16 It is a diagram with Figure 14 FIG. 5 is a diagram of exemplary resource allocation in the time and frequency domains associated with the operation of FIG.

[0271] When Repetition is set to "On" for a CSI-RS resource set, multiple CSI-RS resources can be repeatedly used on the same Tx beam, and when Repetition is set to "Off" for a CSI-RS resource set, different CSI-RS resources can be repeatedly sent on different Tx beams.

[0272] 3.DL BM related beam indication

[0273] The UE may receive a list of at least up to M candidate transmission configuration indication (TCI) states for QCL indication via RRC signaling. M depends on the UE capability and may be 64.

[0274] Each TCI state can be configured with one RS set. Table 10 describes an example of TC-State IE. TC-State IE is related to the QCL type corresponding to one or two DL RSs.

[0275] [Table 10]

[0276]

[0277]

[0278] In Table 10, "bwp-Id" identifies the DL BWP where the RS is located, "cell" indicates the carrier where the RS is located, and "referencesignal" indicates the reference antenna port(s) used as the QCL source for the target antenna port(s) or the RS including the reference antenna port(s). The target antenna port(s) can be used for CSI-RS, PDCCH DMRS, or PDSCH DMRS.

[0279] 4. Quasi-co-sited (QCL)

[0280] A UE may receive a list of up to M TCI state configurations to decode the PDSCH based on a detected PDCCH carrying DCI intended for a given cell. M depends on the UE capabilities.

[0281] Each TCI-State includes parameters for establishing a QCL relationship between one or more DL RSs and PDSCH DM-RS ports, as described in Table 10. The QCL relationship is established using the RRC parameter qcl-Type1 for the first DL RS and the RRC parameter qcl-Type2 for the second DL RS (if configured).

[0282] The QCL type of each DL RS is given by a parameter 'qcl-Type' included in QCL-Info and may have one of the following values.

[0283] - 'QCL-TypeA': {Doppler shift, Doppler spread, average delay, delay spread}

[0284] - 'QCL-TypeB': {Doppler shift, Doppler spread}

[0285] - 'QCL-TypeC': {Doppler shift, average delay}

[0286] - 'QCL-TypeD': {spatial Rx parameters}

[0287] For example, if the target antenna port is for a specific NZP CSI-RS, the NZP CSI-RS antenna port can be indicated / configured to QCL with a specific TRS from the perspective of QCL-Type A and to QCL with a specific SSB from the perspective of QCL-Type D. Upon receiving this indication / configuration, the UE can use the Doppler value and delay value measured in the QCL-Type A TRS to receive the NZP CSI-RS and apply the Rx beam for receiving the QCL-Type D SSB to receive the NZP CSI-RS.

[0288] UL BM process

[0289] In the UL BM, beam reciprocity (or beam correspondence) between the Tx and Rx beams may or may not be established depending on the UE implementation. If Tx-Rx beam reciprocity is established at both the BS and the UE, the UL beam pair can be derived from the DL beam pair. However, if Tx-Rx beam reciprocity is not established at either the BS or the UE, a separate process for determining the UL beam is required from determining the DL beam pair.

[0290] In addition, even when both the BS and the UE maintain beam correspondence, the BS may apply the UL BM procedure to determine the DLTx beam without requesting the UE to report its preferred beam.

[0291] UL BM can be performed based on beamformed UL SRS transmission. Whether to perform UL BM on an SRS resource set can be determined by a usage parameter (RRC parameter). If the usage is determined to be BM, only one SRS resource can be transmitted for each of multiple SRS resource sets at a given time.

[0292] The UE may be configured (via RRC signaling) with one or more SRS resource sets, where one or more SRS resource sets are configured by SRS-ResourceSet (RRC parameter). For each SRS resource set, the UE may be configured with K ≥ 1 SRS resources, where K is a natural number and the maximum value of K is indicated by SRS_capability.

[0293] Similar to DL BM, the UL BM procedure can also be divided into Tx beam scanning at the UE and Rx beam scanning at the BS.

[0294] Figure 17 An example of an SRS-based UL BM procedure is illustrated.

[0295] Figure 17 (a) shows the process of BS determining Rx beamforming, and Figure 17 (b) shows the process of UE performing Tx beam scanning.

[0296] Figure 18 is a flowchart illustrating an example of an SRS-based UL BM procedure.

[0297] -The UE receives RRC signaling (e.g., SRS-Config IE) from the BS including a usage parameter (RRC parameter) set to BM (S1810). The SRS-Config IE is used to configure SRS transmission. The SRS-Config IE includes an SRS resource list and an SRS resource set list. Each SRS resource set refers to a collection of SRS resources.

[0298] -The UE determines Tx beamforming of the SRS resource to be transmitted based on the SRS-SpatialRelation Info included in the SRS-Config IE (S1820). Here, the SRS-SpatialRelation Info is configured for each SRS resource and indicates whether the same beamforming as that for SSB, CSI-RS, or SRS is applied to each SRS resource.

[0299] -If SRS-SpatialRelationInfo is configured for the SRS resource, the same beamforming as that used in SSB, CSI-RS, or SRS is applied and transmitted. However, if SRS-SpatialRelationInfo is not configured for the SRS resource, the UE randomly determines Tx beamforming and transmits the SRS based on the determined Tx beamforming (S1830).

[0300] For P-SRS with "SRS-ResourceConfigType" set to "Periodic":

[0301] i) If SRS-SpatialRelationInfo is set to "SSB / PBCH", the UE transmits the corresponding SRS by applying the same spatial domain transmit filter as the spatial domain receive filter used to receive SSB / PBCH (or a spatial domain transmit filter generated by the spatial domain receive filter);

[0302] ii) If SRS-SpatialRelationInfo is set to "CSI-RS", the UE transmits the SRS by applying the same spatial domain transmission filter as that used to receive the CSI-RS;

[0303] iii) If SRS-SpatialRelationInfo is set to "SRS", the UE transmits the corresponding SRS by applying the same spatial domain transmission filter as that used to transmit the SRS.

[0304] - In addition, as in the following three cases, the UE may or may not receive feedback on the SRS from the BS (S1840).

[0305] i) When Spatial_Relation_Info is configured for all SRS resources in the SRS resource set, the UE transmits SRS on the beam indicated by the BS. For example, if Spatial_Relation_Info indicates the same SSB, CRI, or SRI, the UE repeatedly transmits SRS on the same beam.

[0306] ii) Spatial_Relation_Info may not be configured for all SRS resources in an SRS resource set. In this case, the UE may transmit while randomly changing the SRS beamforming.

[0307] iii) Spatial_Relation_Info may be configured only for some SRS resources in an SRS resource set. In this case, the UE may transmit SRS on the indicated beam for the configured SRS resource, but for SRS resources not configured with Spatial_Relation_Info, the UE may perform transmission by applying random Tx beamforming.

[0308] In the proposed method described later, a beam may refer to an area for performing a specific operation (e.g., LBT or transmission) by concentrating power in a specific direction and / or a specific space. In other words, the UE or BS can perform operations such as LBT or transmission by targeting a specific area (i.e., beam) corresponding to a specific space and / or a specific direction. Therefore, each beam may correspond to each space and / or each direction. In addition, the UE or BS may use a spatial domain filter corresponding to each space and / or each direction in order to use each beam. That is, one spatial domain filter may correspond to one or more beams. The UE or BS may perform operations such as LBT or transmission using a spatial domain filter corresponding to the beam (or space and / or direction) to be used.

[0309] For example, the UE or BS may perform LBT using a spatial domain filter corresponding to an LBT beam in the space and / or direction used for the corresponding LBT beam, or perform DL / UL transmission using a spatial domain filter corresponding to a Tx beam in the space and / or direction used for the corresponding Tx beam.

[0310] In high frequency bands of 52.6 GHz or higher, due to the relatively larger path loss compared to low frequency bands, it is possible to consider omnidirectional LBT (hereinafter, O-LBT) for performing LBT in all directions, omnidirectional transmission and reception, directional LBT (hereinafter, D-LBT) for performing LBT only in a specific beam direction, and directional transmission and reception through techniques such as analog beamforming using multiple antennas.

[0311] In this case, since O-LBT and D-LBT differ in the area and direction in which LBT is performed, the energy detection (ED) threshold used to determine whether a channel is idle or busy through energy measurement needs to be configured differently. In addition, since LBT is directional, when beams of different directions are multiplexed within a COT successfully obtained through D-LBT, or when DL / UL beams are used for DL / UL transmission and reception through DL / UL switching, the direction in which LBT is performed and the ED threshold are closely related to each other. Therefore, a method for configuring an appropriate ED threshold and performing multiplexing is required.

[0312] A typical CAP performed for transmission in the U-band is LBT. LBT is a mechanism for preventing collisions between transmissions by allowing transmission of corresponding signals when the noise level, which is a result of comparing the surrounding interference level measured by the BS and / or UE to transmit a signal with a specific threshold (such as an ED threshold), is less than a specific level.

[0313] Figure 19 An exemplary D-LBT and an exemplary O-LBT are shown.

[0314] Figure 19 (a) illustrates a D-LBT including a specific beam direction LBT and / or a beam group unit LBT, and Figure 19 (b) Schematic diagram of O-LBT.

[0315] In a legacy NR-U system (e.g., Rel-16 NR-U), if Figure 9As described above, once a channel is determined to be idle by performing CAP (i.e., LBT), a DL / UL signal / channel has already been transmitted. On the other hand, in a legacy NR-U system, the LBT band is aligned with the LBT band of another RAT to enable coexistence with other RATs (e.g., Wi-Fi), and CAP (i.e., LBT) is performed omnidirectionally. In other words, non-directional LBT is already performed in a legacy NR-U system.

[0316] However, Rel-17 NR-U, which is used to transmit DL / UL signals / channels in a higher band (e.g., a band of 52.6 GHz or higher) than the 7 GHz U-band used in the conventional NR-U system, can utilize D-LBT. D-LBT transmits signals / channels by concentrating energy in a specific beam direction to overcome a path loss greater than that in the 7 GHz band used in the conventional system. That is, in Rel-17 NR-U, D-LBT can be used to reduce path loss, transmit DL / UL signals / channels over a wider coverage area, and improve efficiency even when coexisting with other RATs (e.g., WiGig).

[0317] refer to Figure 19 (a) When a beam group consists of beams #1 to #5, performing LBT based on beams #1 to #5 can be referred to as beam group-based LBT. Alternatively, performing LBT on any one of beams #1 to #5 (e.g., beam #3) can be referred to as beam-specific LBT. In this case, beams #1 to #5 can be consecutive (or adjacent) beams, but can also be discontinuous (or non-adjacent) beams. Furthermore, the number of beams included in a beam group does not necessarily need to be multiple, and a single beam can form a beam group.

[0318] Figure 19 (b) illustrates O-LBT. When omnidirectional beams constitute one beam group and LBT is performed on a beam group basis, this can be interpreted as performing O-LBT. In other words, if all-directional beams (i.e., omnidirectional beams as a beam set covering a specific sector in a cell) are included in one beam group, this can mean O-LBT.

[0319] In other words, in the case of high-frequency bands, coverage may be limited due to significant path loss. To overcome this coverage issue, multi-antenna technology can be used. For example, narrow beam transmission can be performed to transmit signals by concentrating energy in a specific direction, rather than omnidirectional transmission.

[0320] In the high-frequency U-band, along with CAP such as the aforementioned LBT, it is necessary to consider combining it with beam-based transmission. For example, to perform D-LBT in a specific direction, D-LBT can be performed only in the corresponding direction, or LBT can be performed in units of beam groups that include beams in the corresponding direction. Then, if the channel is determined to be idle, transmission can be performed. Here, the beam group can include a single beam or multiple beams. If the beam group includes an omnidirectional beam, D-LBT can be expanded to O-LBT.

[0321] Since beam-based transmission concentrates energy in a specific direction to transmit a signal, the interference affecting neighboring BSs / UEs (except for nodes located in the transmission direction) is likely to be relatively small compared to omnidirectional transmission. In other words, it can be considered that spectrum sharing is naturally formed in beam-based transmission because beam-based transmission only causes interference in a specific direction. Therefore, if certain conditions are met, channel access opportunities can be increased, and system performance can be improved by performing beam-based transmission without performing LBT.

[0322] Information about the beam group including each beam and information about at least one beam included in each beam group can be configured, and the CWS and backoff counter values ​​can be managed separately for each individual beam or each individual beam group. Therefore, when LBT is performed, events such as a CWS reset / increment or a backoff counter decrement can potentially affect each beam and the beam group including each beam. For example, if feedback for data transmitted via LBT in a specific beam direction is a negative acknowledgement (NACK), and the CWS value for that beam direction increases, the increase in the CWS value is also reflected in the CWS managed by the beam group including the corresponding beam, allowing the CWS value for that beam group to increase. On the other hand, even if the CWS value for the corresponding beam direction increases, the CWS value for that beam group can be managed independently without affecting the beam group including the corresponding beam. Furthermore, the backoff counter values ​​managed on a per-beam or per-beam group basis can also be configured as described above, such that the backoff counter value for each beam and the backoff counter value for each beam group are managed independently or depend on each other to affect each other.

[0323] Beam-based LBT and beam-group-based LBT can be interchanged under certain conditions. In the case of UL transmission, the BS can indicate the LBT type to be used among the two LBT types (i.e., beam-based LBT and beam-group-based LBT). In the case of CG UL transmission, when resources are configured for the CG UL transmission, the type of LBT to be performed on each resource can also be configured. If delay-sensitive data transmission is indicated together with LBT in a specific beam direction, data may not be sent due to LBT failure. Therefore, channel access opportunities can be increased by allocating multiple LBT opportunities to other beams in the beam group including the corresponding beam.

[0324] In the present disclosure, a beam-based LBT process or a beam group-based LBT process can essentially refer to a Category 3 or Category 4 LBT with random backoff. In beam-based LBT, the energy measured by performing carrier sensing in a specific direction is compared with an ED threshold. If the energy measured by performing carrier sensing is lower than the ED threshold, the channel in the corresponding beam direction is considered idle. If the energy measured by performing carrier sensing is higher than the ED threshold, the channel in the corresponding beam is considered busy.

[0325] The beam group-based LBT process is to perform the above-mentioned LBT process in all beam directions included in the beam group, and when LBT is successful, a random backoff-based LBT process is performed using the corresponding beam as a representative, similar to multi-CC LBT when there is a pre-configured / indicated beam in a specific direction (e.g., a representative beam) in the beam group, and Cat-1 or Cat-2 LBT based on non-random backoff is performed on the remaining beams included in the beam group to transmit the signal. In the beam group-based LBT process, according to the regulations of each country / region, the random backoff-based LBT process may be performed on the representative beam, and no LBT may be performed on the remaining beams included in the beam group to transmit the signal through each of the remaining beams.

[0326] Before describing the proposed method, the NR-based channel access scheme for unlicensed band used in this disclosure is classified as follows.

[0327] - Category 1 (CAT-1): After a switching gap within the COT, the next transmission immediately follows the previous transmission, and the switching gap is shorter than 16us, even including the transceiver turnaround time. Cat-1 LBT can correspond to the above-mentioned Type 2C CAP.

[0328] - Category 2 (Cat-2): LBT method without backoff. Once the channel is confirmed to be idle during a specific time period shortly before transmission, transmission can be performed immediately. Cat-2 LBT can be subdivided according to the length of the minimum sensing duration required for channel sensing immediately before transmission. For example, Cat-2 LBT with a minimum sensing duration of 25us can correspond to the above-mentioned Type 2A CAP, and Cat-2 LBT with a minimum sensing duration of 16us can correspond to the above-mentioned Type 2B CAP. The minimum sensing duration is merely exemplary, and a minimum sensing duration of less than 25us or 16us (e.g., a minimum sensing duration of 9us) is also available.

[0329] Category 3 (Cat-3): An LBT method with backoff based on a fixed contention window size (CWS) i. The transmitting entity selects a random number N in the range from 0 to a (fixed) maximum CWS value and decrements the counter each time it determines the channel is idle. When the counter reaches 0, the transmitting entity is allowed to transmit.

[0330] Category 4 (Cat-4): An LBT method with variable CWS-based backoff. The transmitting entity selects a random number N in the range of 0 to a (variable) maximum CWS value and decrements the counter value each time the channel is determined to be idle. When the counter value reaches 0, the transmitting entity is allowed to perform the transmission. If the transmitting entity receives feedback indicating a reception failure of the transmission, the transmitting entity will increase the maximum CWS value by one level, select a random number again within the increased CWS value, and perform the LBT procedure. Category-4 LBT can correspond to the above-mentioned Type 1 CAP.

[0331] The definitions related to QCL described in this disclosure may follow one of the above-mentioned definitions related to QCL. Similarly, the definition of the QCL concept can be modified to assume co-location transmission between antenna ports for QCL (e.g., the UE can assume that the antenna ports transmit signals at the same transmission point). The scope of this disclosure includes such similar modified examples. For ease of description, the above-mentioned QCL-related definitions are used interchangeably in this disclosure.

[0332] By the above definition, the UE may not assume that "non-quasi-co-located (NQC) antenna ports" have the same large-scale channel properties between them. That is, in this case, a typical UE receiver should perform independent processing for timing acquisition and tracking, frequency offset estimation and compensation, delay estimation, and Doppler estimation for each configured NQC antenna port. The UE may advantageously perform the following operations for antenna ports that can assume QCL.

[0333] Regarding delay spread and Doppler spread, the UE may apply the same power-delay-profile, delay spread, Doppler spectrum, and Doppler spread estimation result of one antenna port to a Wiener filter or the like used for channel estimation of another antenna port.

[0334] - Regarding frequency shift and reception timing, after performing time and frequency synchronization for one antenna, the UE can apply the same synchronization to demodulation of the other antenna port.

[0335] - Regarding average received power, the UE may average the RSRP measurements of multiple antenna ports.

[0336] Meanwhile, when beam reciprocity is established between DL beams and UL beams, the process for determining a DL beam pair or the process for determining a UL beam pair can be omitted. This also applies when establishing a beam correspondence.

[0337] Here, "establishing beam reciprocity (or beam correspondence)" may mean assuming that, in communication between a BS and a UE, the BS Tx beam and the BS Rx beam coincide, and the UE Tx beam and the UE Rx beam coincide. Here, the BS Tx beam and the BS Rx beam may refer to a DL Tx beam and a DL Rx beam, respectively, and the UE Tx beam and the UE Rx beam may refer to a UL Tx beam and a UL Rx beam, respectively. Here, the Tx beam may refer to a transmission beam, and the Rx beam may refer to a reception beam.

[0338] For the following reasons, it may be desirable to configure all DL signals / channels (or all UL signals / channels) included in one Tx burst to be signals / channels having a spatial (partial) QCL relationship. Figure 20 As shown, when the BS transmits a Tx burst consisting of a total of 4 time slots after succeeding in LBT, the BS can transmit a signal in 3 time slots in the beam direction of A and then transmit a signal in the fourth time slot in the beam direction of C.

[0339] However, when the BS transmits a signal in the beam direction of A, the Wi-Fi AP coexisting in the corresponding U band may not be able to detect the signal transmitted in the beam direction of A and determine that the channel is idle. After LBT succeeds, the Wi-Fi AP can start transmitting and receiving signals. In this case, if the BS transmits a signal in the beam direction of C starting from time slot #k+3, this signal may act as interference to the corresponding Wi-Fi signal. Therefore, when the BS that has already performed transmission in the direction of A performs transmission by switching the beam direction without additional LBT, the BS may cause interference with another coexisting wireless node. Therefore, it may be desirable not to switch the Tx beam direction of the Tx burst transmitted after the BS's LBT succeeds.

[0340] In the NR system, a method of signaling beam information to be used by the UE during UL transmission and reception by associating a DL signal and a UL signal is being considered. For example, if there is a beam direction generated by the UE on a channel state information reference signal (CSI-RS) resource by associating the CSI-RS resource with a sounding reference signal (SRS) resource, when the UE transmits an SRS on an SRS resource linked to the CSI-RS resource (or when the UE transmits a PUSCH scheduled by a UL grant, the SRS resource linked to the CSI-RS resource is signaled by the UL grant), the UE can use a Tx beam corresponding to the CSI-RS Rx beam to transmit a UL signal. In this case, the UE can configure the relationship between a specific Rx beam and a specific Tx beam in an implementation when there is a beam correspondence capability of the UE. Alternatively, when there is no beam correspondence capability of the UE, the relationship between a specific Rx beam and a specific Tx beam can be configured by training the BS and the UE.

[0341] Therefore, when defining the association relationship between the DL signal and the UL signal, COT sharing can be allowed between the DL Tx burst consisting of the DL signal / channel in a spatial (partial) QCL relationship with the DL signal and the UL Tx burst consisting of the UL signal / channel in a spatial (partial) QCL relationship with the UL signal associated with the DL signal.

[0342] Here, the UL signal / channel may include at least one or more of the following signals / channels:

[0343] -SRS, Demodulation Reference Signal (DMRS) for PUCCH, DMRS for PUSCH, PUCCH, PUSCH, or PRACH

[0344] Here, the DL signal / channel may include at least one or more of the following signals / channels:

[0345] -PSS, SSS, DMRS for PBCH, PBCH, Tracking Reference Signal (TRS), CSI-RS for tracking, CSI-RS for CSI acquisition, CSI-RS for Radio Resource Management (RRM) measurement, CSI-RS for BM, DMRS for PDCCH, DMRS for PDSCH, PDCCH (or Control Resource Set (CORESET) in which PDCCH may be transmitted), PDSCH, or a modified signal of the above-listed signals or related signals or a newly introduced signal, placed in front of a Tx burst for tracking, (fine) time / frequency synchronization, coexistence, power saving, or frequency reuse factor = 1

[0346] Meanwhile, each proposed method described later may be combined with and applied together with the other proposed methods unless each proposed method conflicts with the other proposed methods.

[0347] As described above, in the U-band, signal transmission should follow the "LBT" rule through CCA operation. That is, when a signal equal to or greater than a specific CCA threshold is not detected during a specific sensing period, the transmitter can perform signal transmission.

[0348] Considering CCA operations, first, since each BS (or TRP) or UE should always perform "energy sensing" before transmission operations, even from the perspective of the BS / UE's Rx antenna, it is necessary to specify a definition or restriction of operations similar to the above-mentioned energy sensing. This is because the energy sensing results may vary depending on the implementation, such as whether the BS receives signals using a sectorized antenna or whether the BS receives signals by applying a specific Rx beam pattern.

[0349] Therefore, for example, when the gNB Rx beam pattern applied during energy sensing and the Tx beam pattern during transmission after CCA are applied differently, the beam area for determining CCA and the beam area for Tx signals are different, so that there is a possibility of causing large interference to surrounding communications.

[0350] Before describing the proposed method, the overall operation procedures of the UE and the BS for implementing the proposed method to be described will now be described.

[0351] Figure 21 A method for a UE to transmit a UL signal according to at least one proposed method of the present disclosure is illustrated.

[0352] refer to Figure 21, the UE may obtain an ED threshold for energy sensing (S2101). For example, the UE may obtain the ED threshold based on at least one of [Proposed Method #1], [Proposed Method #2], or [Proposed Method #4]. However, the UE may also obtain the ED threshold using existing technologies and methods other than the method proposed in the present disclosure.

[0353] The UE may obtain the LBT-BW (S2103). For example, the UE may obtain the LBT-BW based on [Proposed Method #3]. However, the method of obtaining the LBT-BW according to [Proposed Method #3] may be omitted. If the method of obtaining the LBT-BW according to [Proposed Method #3] is omitted, the UE may perform LBT based on the LBT-BW (e.g., 20 MHz) according to the existing technology, or perform LBT using the configured BWP size as the LBT-BW unit.

[0354] The UE may perform LBT based on the obtained ED threshold and / or LBT-BW (S2105). In addition, if LBT is successful, the UE may send a UL signal to the BS (S2107). For example, the UE may perform LBT based on [Proposed Method #2] for multiplexed Tx beams and send a UL signal.

[0355] Figure 22 A method for a BS to transmit a DL signal according to at least one proposed method of the present disclosure is illustrated.

[0356] refer to Figure 22 The BS may obtain an ED threshold value for energy sensing (S2201). For example, the BS may obtain the ED threshold value based on at least one of [Proposed Method #1], [Proposed Method #2], or [Proposed Method #4]. However, the BS may also obtain the ED threshold value using existing technologies and methods other than the proposed method according to the present disclosure.

[0357] The BS may acquire an LBT-BW (S2203). For example, the BS may configure the LBT-BW based on [Proposed Method #3]. However, the method of configuring the LBT-BW according to [Proposed Method #3] may be omitted. If the method of configuring the LBT-BW according to [Proposed Method #3] is omitted, the BS may perform LBT based on the LBT-BW (e.g., 20 MHz) according to the existing technology, or perform LBT using the configured BWP size as the LBT-BW unit.

[0358] The BS may perform LBT based on the obtained ED threshold and / or LBT-BW (S2205). If LBT succeeds, the BS may send a DL signal to the UE (S2207). For example, the BS may perform LBT on the multiplexed Tx beams based on [Proposed Method #2] and send a DL signal.

[0359] Hereinafter, a proposed method of the present disclosure for solving the above-mentioned problems will be described.

[0360] [Proposed Method #1]

[0361] When ED measurement related requirements for UE are defined (eg, in the RAN4 standard), the ED threshold may be configured.

[0362] 1. Example #1-1

[0363] A method of defining an ED measurement type or ED measurement category for a specific ED threshold value. In this case, the ED threshold value can be different according to the ED measurement type / category.

[0364] 2. Example #1-2

[0365] The UE may have previously reported its ED measurement capability to the BS. Based on the information about the ED measurement capability, the BS may indicate / configure the spatial relationship between the LBT beam and a specific RS to / for the UE, and indicate / configure the ED measurement type / category and ED threshold for D-LBT, as well as UL scheduling information.

[0366] In this case, the ED threshold may be configured differently for / indicated differently to the UE according to a DL signal in a spatial relationship with a UL signal / channel to be transmitted by the UE.

[0367] A detailed description of [Proposed Method #1] will now be given.

[0368] In the case of performing D-LBT through a specific LBT beam (e.g., Rx beam pattern) using a specific directional antenna, the CCA range should not exceed the interference range of (one or more) Tx beams affecting interference. In addition, when configuring the CCA range and EDT (e.g., ED threshold) of D-LBT, the interference range of (one or more) Tx beams affecting interference should be considered. At the same time, the ED measurement-related requirements of the UE may be defined in a standard document such as RAN4, and the ED measurement type / category may be defined based on a specific ED threshold. Alternatively, when the Tx power or LBT BW of the UE is equal and the size of the LBT beam (e.g., the width of the beam) is different, so that different ED measurement types / categories are defined, different ED thresholds may be configured based on the ED measurement type / category.

[0369] The UE may have previously reported information about its ED capability to the BS, and the BS may indicate the ED measurement type / category and ED threshold of D-LBT together with UL scheduling information based on the information about the UE's ED capability.

[0370] When the UE performs UL transmission through its antenna, the above-mentioned ED measurement-related requirements of the UE can be defined as the shape of the beam pattern. For example, when UL transmission in a space shaped like a virtual sphere occupies area A in the virtual sphere and D-LBT can be performed over area B including area A, the ED measurement type / category can be defined based on the size of area BA (i.e., the difference between area B and area A).

[0371] As another example, ED threshold type 1 (or ED threshold category 1) for the same specific ED threshold may be a wide beam in which the beamwidth of an LBT beam (e.g., an Rx beam pattern) is wider than the beamwidth of a Tx beam. In this case, the wide beam may refer to a beam with a relatively large main lobe width in the beam pattern.

[0372] ED threshold type 2 (or ED threshold category 2) can be defined in the ED measurement requirements as a relatively narrow beam, in which the difference between the beam width of the LBT beam (e.g., Rx beam pattern) and the beam width of the Tx beam is not large. Here, a narrow beam may refer to a beam in which the width of the main lobe in the beam pattern is relatively small and the difference between the width of the main lobe of the Tx beam and the width of the side lobe in the beam pattern is not large (e.g., a difference equal to or less than a specific value). For example, when establishing a beam correspondence, the Tx beam direction corresponding to the CSI-RS Rx beam may be relatively narrow relative to the Tx beam direction corresponding to the SSB Rx beam. In other words, when establishing a beam correspondence, the Tx beam direction corresponding to the CSI-RS Rx beam may be a relatively wide beam compared to the Tx beam direction corresponding to the SSB Rx beam.

[0373] Depending on the capabilities of the UE, some UEs may support both ED threshold type 1 and ED threshold type 2 (or ED threshold category 1 and ED threshold category 2), and other UEs may only support specific types / categories of ED measurements.

[0374] The BS can configure the LBT beam and specific RS into a spatial relationship based on the information about the ED measurement type (or category) capability reported by the UE, and indicate / configure the ED measurement type (or category) and ED threshold of D-LBT to the UE during UL scheduling.

[0375] For example, if the DL RS spatially associated with the LBT beam is a CSI-RS, ED measurement type 1 (or category 1) may be configured, and if the DL RS spatially associated with the LBT beam is an SSB, ED measurement type 2 (or category 2) may be configured. Furthermore, if the DL RS spatially associated with the LBT beam is an SRS, ED measurement type 3 (or category 3) may be configured.

[0376] After configuring the ED measurement type (or category) as described above, when the BS performs UL scheduling for the UE, the BS can indicate the direction of the LBT beam in which D-LBT is to be performed for each UL channel / signal and the ED measurement type (or category). In addition, the ED threshold value can be configured differently for the UE / indicated differently to the UE depending on the DL signal that is spatially related to the UL signal / channel to be transmitted by the UE.

[0377] [Proposed Method #2]

[0378] The BS and the UE may configure an ED measurement type (or category) and an ED threshold in consideration of the direction of (one or more) Tx beams to be transmitted within the COT and the interference range.

[0379] 1. Example #2-1

[0380] An ED measurement type (or category) and an ED threshold covering the total interference range of one or more Tx beams to be transmitted through spatial division multiplexing (SDM) within a COT may be configured.

[0381] (1) The ED threshold may be configured / indicated based on a Tx beam having {maximum effective isotropic radiated power (EIRP), average EIRP, or minimum EIRP} among one or more Tx beams to be transmitted through SDM within the COT.

[0382] (2) D-LBT can be performed simultaneously on one or more Tx beams using a single LBT beam that covers the interference range of one or more Tx beams to be transmitted via SDM within the COT. In this case, the single LBT beam can be a relatively wide beam.

[0383] For example, reference Figure 23 (a) When four Tx beams (Tx beam 1 to Tx beam 4) are multiplexed using SDM, the BS or UE can perform D-LBT using a single LBT beam that covers all four Tx beams (Tx beam 1 to Tx beam 4). For example, "a single LBT beam covers all four Tx beams" may mean that the LBT area of ​​a single LBT beam includes the total interference range of the four Tx beams.

[0384] In addition, when D-LBT is successfully performed using an LBT beam, the BS or UE can perform DL / UL transmissions through Tx Beams 1 to 4 multiplexed using SDM. In this case, each DL / UL transmission can be scheduled through each of Tx Beams 1 to 4, and the scheduled DL / UL signals / channels can be transmitted through SDM. On the other hand, DL / UL transmissions can be performed on adjacent Tx beams. For example, if a DL / UL signal / channel is scheduled on Tx Beam 1 and Tx Beam 2, the DL / UL signal / channel scheduled through Tx Beam 1 and Tx Beam 2 can be transmitted through SDM.

[0385] (3) D-LBT can be performed sequentially using multiple LBT beams that cover the interference range of one or more Tx beams to be transmitted through SDM within the COT. Depending on the success or failure of D-LBT of the multiple LBT beams, Tx beams in beam directions that can be continuously transmitted without gaps can be transmitted through SDM among the beam directions in which D-LBT succeeded. Each of the multiple LBT beams can be a relatively narrow beam.

[0386] For example, reference Figure 23 (b) When four Tx beams (Tx beam 1 to Tx beam 4) are multiplexed using SDM, the BS or UE can perform D-LBT on LBT beam 1 to LBT beam 4 covering the four Tx beams, respectively. Here, LBT beam 1 is a beam covering Tx beam 1, and LBT beam 2 is a beam covering Tx beam 2. In addition, LBT beam 3 is a beam covering Tx beam 3, and LBT beam 4 is a beam covering Tx beam 4. For example, the LBT area of ​​LBT beam 1 includes the interference range of Tx beam 1 and may be greater than or equal to the interference range of Tx beam 1 corresponding to the LBT area of ​​LBT beam 1. In other words, the LBT area of ​​each LBT beam should necessarily include the interference range of the Tx beam corresponding to each LBT beam, and may be greater than or equal to the interference range of the Tx beam. That is, the LBT area of ​​each LBT beam may be greater than or equal to the interference range of the Tx beam corresponding to each LBT beam, and may include all interference ranges of the corresponding Tx beam.

[0387] The BS or UE can perform D-LBT on each of LBT beams 1 to 4 simultaneously or sequentially. For example, the BS or UE can perform D-LBT on each LBT beam sequentially from D-LBT using LBT beam 1 to D-LBT using LBT beam 4, or perform D-LBT on LBT beams 1 to LBT beam 4 simultaneously.

[0388] In this case, among the successful LBT beams in D-LBT, the Tx beam can be used for DL / UL transmission through SDM in a Tx beam direction capable of continuous transmission without gaps.

[0389] For example, if D-LBT for LBT beam 2 fails and D-LBT for LBT beams 1, 3, and 4 succeeds, Tx beam 3 and Tx beam 4 can be used for DL / UL transmission through SDM. For example, each DL / UL transmission can be scheduled through each of Tx beam 3 and Tx beam 4, and the scheduled DL / UL signal / channel can be transmitted through SDM. On the other hand, transmission of one DL / UL signal / channel can be performed on Tx beam 3 and Tx beam 4. In other words, one DL / UL signal / channel can be scheduled to be transmitted through Tx beam 3 and Tx beam 4, and the DL / UL signal / channel scheduled on Tx beam 3 and Tx beam 4 can be transmitted through SDM.

[0390] (4) In the case where multiple TRPs are configured, if different TRPs schedule UL signals / channels in the same symbol for the UE so that the UE should simultaneously transmit UL signals / channels to different TRPs in the same symbol (for example, if the UE should simultaneously transmit UL signals / channels to different TRPs through SDM), the Tx power is divided by the number of Tx beams used by the UE for simultaneous transmission so that the Tx power allocated to each Tx beam can be reduced. Therefore, based on the reduced Tx power applied to each Tx beam, the ED threshold for the LBT beam in the direction corresponding to each Tx beam can be configured to increase. For example, the ED threshold for the LBT beam can be increased as much as the reduced Tx power applied to each Tx beam, or it can be increased to correspond to the reduced Tx power, or it can be increased to be inversely proportional to the reduced Tx power.

[0391] In this case, if the UE has multiple panels for multiple Tx beams (or multiple LBT beams), the UE can perform D-LBT according to the LBT beams indicated for each panel. On the other hand, method (4) of embodiment #2-1 can be applied only to the UE in a limited manner.

[0392] 2. Example #2-2

[0393] An ED measurement type (or category) and an ED threshold covering the total interference range of one or more Tx beams to be transmitted through TDM within the COT may be configured.

[0394] (1) The ED threshold may be configured / indicated based on {maximum EIRP, average EIRP, minimum EIRP, Tx beam to be transmitted first, or Tx beam with longest Tx duration} among one or more Tx beams to be transmitted by TDM within the COT.

[0395] (2) D-LBT can be performed simultaneously on one or more Tx beams using a single LBT beam that covers the interference range of one or more Tx beams to be transmitted via TDM within the COT. The single LBT beam can be a relatively wide beam. DL / UL signals or channels can be transmitted sequentially for each Tx beam.

[0396] For example, reference Figure 24 (a) When four Tx beams (Tx beam 1 to Tx beam 4) are multiplexed using TDM, the BS or UE can perform D-LBT using a single LBT beam that covers all four Tx beams (Tx beam 1 to Tx beam 4). For example, "a single LBT beam covers all four Tx beams" may mean that the LBT area of ​​the single LBT beam includes the total interference range of the four Tx beams.

[0397] In addition, when D-LBT is successfully performed using an LBT beam, the BS or UE can perform DL / UL transmission through Tx beam 1 to Tx beam 4 multiplexed using TDM. In this case, each DL / UL transmission can be scheduled through each of Tx beam 1 to Tx beam 4, and the scheduled DL / UL signals / channels can be multiplexed using TDM, and the DL / UL signals / channels from the DL / UL signal / channel for Tx beam 1 to the DL / UL signal / channel for Tx beam 4 can be transmitted sequentially. On the other hand, DL / UL transmission can be performed on adjacent Tx beams. For example, if a first DL / UL signal / channel is scheduled on Tx beam 1 and Tx beam 2, and a second DL / UL signal / channel is scheduled on Tx beam 3 and Tx beam 4, the first DL / UL signal / channel and the second DL / UL signal / channel can be transmitted sequentially through TDM.

[0398] exist Figure 24 In case (a), since the COT is obtained by determining that the channel is idle through the LBT beam when Tx beam switching is performed, as in the case where the Tx beam is switched from Tx beam 1 to Tx beam 2 or from Tx beam 1 and Tx beam 2 to Tx beam 3 and Tx beam 4, DL / UL signals / channels can be sent by performing Tx beam switching without performing additional LBT (i.e., based on the no-LBT mode).

[0399] (3) D-LBT can be performed sequentially using multiple LBT beams that cover the interference range of one or more Tx beams to be transmitted via TDM within the COT. DL / UL signals / channels can be sequentially transmitted via the Tx beams corresponding to the LBT beams for which D-LBT was successful. Each of the multiple LBT beams can be a relatively narrow beam.

[0400] For example, reference Figure 24 (b) When four Tx beams (Tx beam 1 to Tx beam 4) are multiplexed using TDM, the BS or UE can perform D-LBT on LBT beam 1 to LBT beam 4 covering the four Tx beams, respectively. Here, LBT beam 1 is a beam covering Tx beam 1, and LBT beam 2 is a beam covering Tx beam 2. In addition, LBT beam 3 is a beam covering Tx beam 3, and LBT beam 4 is a beam covering Tx beam 4. For example, the LBT area of ​​LBT beam 1 includes the interference range of Tx beam 1, and may be greater than or equal to the interference range of Tx beam 1 corresponding to the LBT area of ​​LBT beam 1. In other words, the LBT area of ​​each LBT beam should necessarily include the interference range of the Tx beam corresponding to each LBT beam, and may be greater than or equal to the interference range of the Tx beam. That is, the LBT area of ​​each LBT beam may be greater than or equal to the interference range of the Tx beam corresponding to each LBT beam, and may include all interference ranges of the corresponding Tx beam.

[0401] The BS or UE can perform D-LBT on each of LBT beams 1 to 4 simultaneously or sequentially. For example, the BS or UE can perform D-LBT on each LBT beam sequentially from D-LBT using LBT beam 1 to D-LBT using LBT beam 4, or perform D-LBT on LBT beams 1 to LBT beam 4 simultaneously.

[0402] In this case, DL / UL signals / channels can be sequentially transmitted through the corresponding Tx beams. If D-LBT for some LBT beams is successfully performed through LBT beams 1 to 4, only the DL / UL signals / channels of the Tx beams corresponding to the LBT beams where D-LBT is successful can be transmitted.

[0403] For example, if D-LBT for LBT beam 2 fails and D-LBT for LBT beams 1, 3, and 4 succeeds, the transmission of DL / UL signals / channels scheduled for Tx beam 2 may be discarded, and only DL / UL signals / channels scheduled for Tx beams 1, 3, and 4 may be sent.

[0404] As another example, DL / UL signals may be scheduled across two different Tx beams. For example, a first DL / UL signal / channel may be scheduled across Tx beam 1 and Tx beam 2, and a second DL / UL signal / channel may be scheduled across Tx beam 3 and Tx beam 4. In this case, if D-LBT is successful in all LBT beams, the first DL / UL signal / channel and the second DL / UL signal / channel may be multiplexed using TDM and then transmitted sequentially.

[0405] Meanwhile, if D-LBT for some LBT beams fails, the DL / UL signal / channel scheduled for the Tx beam corresponding to the partial LBT beam may not be transmitted. For example, if D-LBT for LBT beams 1, 3, and 4 succeeds and D-LBT for LBT beam 2 fails, the first DL / UL signal / channel may be discarded and only the second DL / UL signal may be transmitted.

[0406] exist Figure 24 In case (b), since COT has been obtained by determining that the channel is idle through LBT beam 1 to LBT beam 4 as in the case where the Tx beam is switched from Tx beam 1 to Tx beam 2 or from Tx beam 1 and Tx beam 2 to Tx beam 3 and Tx beam 4, when Tx beam switching is performed, DL / UL signals / channels can be transmitted by performing Tx beam switching without performing additional LBT (i.e., based on the no-LBT mode).

[0407] When DL / UL signals / channels are sequentially transmitted via TDM on different Tx beams within the COT obtained after successfully performing D-LBT in (2) and (3) of the above-mentioned embodiment #2-2, if the time required to switch between two different Tx beams is equal to or less than a specific time T, LBT based on non-random backoff, i.e., Cat-2 LBT or Cat-1 LBT, can be performed, and then DL / UL signals / channels can be transmitted via the switched Tx beams. However, if the switching time between the two different Tx beams is greater than T, since COT may not be maintained, Cat-3 LBT or Cat-4 LBT based on random backoff should be performed again.

[0408] Figure 25 The diagram shows that when Figure 24 When switching Tx beams under the same conditions, Cat-2 LBT or Cat-1 LBT based on non-random backoff is performed.

[0409] exist Figure 25 (a) and Figure 25In case (b), although the channel has been confirmed to be idle through the LBT beam (or LBT beam 1 to LBT beam 4) during LBT#1 as in the case where the Tx beam is switched from Tx beam 1 to Tx beam 2 or from Tx beam 1 and Tx beam 2 to Tx beam 3 and Tx beam 4, when Tx beam switching is performed, other noise may occur when the Tx beam is switched over time, before switching the Tx beam, Cat-2 LBT or Cat-1 LBT (LBT#2) based on non-random backoff may be performed using the LBT beam corresponding to the Tx beam after the switching.

[0410] For example, when the Tx beam is switched from Tx beam 1 to Tx beam 2, if the time consumed for switching from Tx beam 1 to Tx beam 2 is equal to or less than T, Cat-2 LBT or Cat-1 LBT based on non-random backoff may be performed using LBT beam 2, and DL / UL signals / channels may be transmitted through Tx beam 2. As another example, when the Tx beam is switched from Tx beam 1 and Tx beam 2 to Tx beam 3 and Tx beam 4, if the time consumed for switching from Tx beam 1 and Tx beam 2 to Tx beam 3 and Tx beam 4 is equal to or less than T, Cat-2 LBT or Cat-1 LBT based on non-random backoff may be performed using LBT beam 3 and LBT beam 4, and DL / UL signals / channels may be transmitted through Tx beam 3 and Tx beam 4.

[0411] In the above example, if the time consumed to switch from Tx beam 1 to Tx beam 2 or from Tx beam 1 and Tx beam 2 to Tx beam 3 and Tx beam 4 exceeds T, LBT beam 2 or LBT beam 3 and LBT beam 4 should be used to perform Cat-3 LBT or Cat-4 LBT based on random backoff to transmit DL / UL signals / channels.

[0412] Figure 25 (a) illustrates that Cat-2 LBT or Cat-1 LBT with non-random backoff is performed using LBT beam 1 before transmitting a DL / UL signal / channel through Tx beam 1. However, since this transmission corresponds to transmission performed immediately after confirming that the channel is idle through the LBT beam (or LBT beams 1 to LBT beams 4), Cat-2 LBT or Cat-1 LBT with non-random backoff using LBT beam 1 can be omitted. That is, after performing Cat-3 LBT or Cat-4 LBT with random backoff through the LBT beam (or LBT beams 1 to LBT beams 4), Cat-2 LBT or Cat-1 LBT with non-random backoff for the first DL / UL signal / channel transmission can be omitted.

[0413] At the same time, if Figure 24 As shown in FIG, whether the Tx beam is switched based on the non-LBT mode without additional LBT, or as Figure 25 As shown, whether to switch the Tx beam after performing Cat-2 LBT or Cat-1 LBT based on non-random backoff may follow the regulations of each country / region.

[0414] (1) of embodiment #2-2 can be used in a limited manner only when there is no other RAT near the UE or BS. The COT length in (1) of embodiment #2-2 can be constrained to be relatively shorter than the COT length in (2) of embodiment #2-2.

[0415] In addition to (4) of embodiment #2-1, the SDM / TDM transmission method and ED threshold configuration method proposed in [Proposed Method #2] can be applied to both BS and UE. Even ED measurement type indication can be limitedly applied to the case where the BS indicates the type to the UE.

[0416] Hereinafter, [Proposed Method #2] will be described in detail.

[0417] During the COT period successfully acquired by D-LBT in a specific LBT beam direction, DL / UL signals / channels can be transmitted in the area where D-LBT is successful. In addition, SDM or TDM can be used within the acquired COT to multiplex Tx beams in different directions.

[0418] On the other hand, transmission of DL / UL signals / channels can be allowed only when the direction and interference range of the Tx beam in different directions are included in the area where the LBT beam performs CCA (i.e., LBT). If it is desired to transmit DL / UL signals / channels through the Tx beam in an area other than the area where the LBT beam has performed CCA (i.e., LBT), D-LBT should be performed again in the direction including the corresponding area.

[0419] In other words, in order to transmit DL / UL signals / channels by performing SDM or TDM on multiple Tx beams within a COT, the LBT beam should be configured / indicated taking into account the direction and interference range of the multiplexed Tx beam, and the corresponding LBT beam should be used to perform D-LBT.

[0420] Therefore, the BS or UE may configure an ED measurement type (or category) and an ED threshold in consideration of the direction of one or more Tx beams to be transmitted within the COT and the interference range.

[0421] First, as a method of configuring the ED threshold of the LBT beam, as in Example #2-1(a), the ED threshold can be configured for the UE / indicated to the UE based on one of the {maximum EIRP, average EIRP or minimum EIRP} among one or more Tx beams to be sent via SDM within the COT.

[0422] According to conservative standards, since the Tx beam with the maximum EIRP may cause interference in a relatively large area, if the ED threshold is configured based on the Tx beam with the maximum EIRP power, the ED threshold may be configured to be relatively low. Alternatively, to slightly increase channel access opportunities, the ED threshold can be configured based on the Tx beam with the lowest EIRP. Alternatively, the ED threshold can be configured based on the average EIRP of the Tx beams to be multiplexed using SDM.

[0423] D-LBT can be performed simultaneously on one or more Tx beams using a single LBT beam that covers the interference range of one or more Tx beams to be transmitted via SDM in the COT. In this case, the single LBT beam can be a relatively wide beam.

[0424] As in the example of [Proposed Method #1], as a spatial relationship between the LBT beam and the SSB, the direction of the LBT beam and the Rx beam pattern can be configured for the UE supporting ED measurement type 1 / the direction of the LBT beam and the Rx beam pattern can be indicated to the UE supporting ED measurement type 1.

[0425] Alternatively, D-LBT may be sequentially performed using a plurality of LBT beams that cover the interference range of one or more Tx beams to be transmitted through SDM in COT. Each of the plurality of LBT beams may be a relatively narrow beam.

[0426] In this case, as in the example of [Proposed Method #1], the spatial relationship between the LBT beam and the CSI-RS can be configured for / indicated to a UE supporting ED Measurement Type 2. Here, depending on the success or failure of D-LBT of multiple LBT beams, SDM can be used to multiplex the Tx beams only in the direction of the Tx beams that are continuously transmitted without gaps among the Tx beams corresponding to the direction of the successful LBT beam in D-LBT.

[0427] For example, if D-LBT based on LBT beam 1 and LBT beams 3 and 4 succeeds, and D-LBT based on LBT beam 2 fails due to D-LBT being performed sequentially through LBT beams 1, 2, 3, and 4, DL / UL signals / channels can be transmitted using only the Tx beams corresponding to LBT beams 3 and 4 through SDM.

[0428] Typically, as in (4) of Example #2-1, in the case where multiple TRPs are configured, if simultaneous transmissions (e.g., SDM) are scheduled for the UE in the same symbol by corresponding UL grants from different TRPs so that UL transmissions should be performed in different TRP directions, the Tx power is divided by the number of simultaneously transmitted Tx beams. Therefore, the ED threshold can be configured to increase based on the reduced Tx power applied to each Tx beam. For example, the ED threshold of the LBT beam can be increased as much as the reduced Tx power applied to each Tx beam, or can be increased to correspond to the reduced Tx beam, or can be increased to be inversely proportional to the reduced Tx power. Thereby, the channel access opportunity of the UE can be increased. In this case, if the UE has multiple panels for multiple Tx beams (or multiple LBT beams), D-LBT can be performed according to the LBT beam indicated for each panel.

[0429] As described in (1) of Example #2-2, even when transmission is performed by TDM in multiple Tx beam directions within the COT, the ED threshold can be configured / indicated based on one of {maximum EIRP, average EIRP, minimum EIRP, Tx beam to be transmitted first, or Tx beam with the longest Tx duration} among one or more Tx beams to be transmitted by TDM within the COT.

[0430] As described in (2) of Example #2-2, D-LBT can be performed simultaneously on one or more Tx beams using a single LBT beam that covers the interference range of one or more Tx beams to be transmitted via TDM within the COT. In this case, the single LBT beam can be a relatively wide beam.

[0431] As in the example of [Proposed Method #1], as a spatial relationship between the LBT beam and the SSB, the direction of the LBT beam and the Rx beam pattern can be configured for the UE supporting ED measurement type 1 / the direction of the LBT beam and the Rx beam pattern can be indicated to the UE supporting ED measurement type 1.

[0432] Alternatively, as described in (3) of Example #2-2, D-LBT may be performed sequentially using multiple LBT beams that cover the interference range of one or more Tx beams to be transmitted via TDM within the COT. Each of the multiple LBT beams may be a relatively narrow beam.

[0433] Therefore, in this case, as in the example of [Proposed Method #1], the spatial relationship between the LBT beam and the CSI-RS can be configured for the UE supporting ED measurement type 2 / the spatial relationship between the LBT beam and the CSI-RS can be indicated to the UE supporting ED measurement type 2.

[0434] As in (2) of Example #2-1 and (2) of Example #2-2, performing D-LBT using a single LBT beam covering the interference range of one or more Tx beams has the advantage of not being significantly affected by the capabilities of the UE or BS.

[0435] In other words, when D-LBT is performed using a single LBT beam covering the interference range of one or more Tx beams, even when the capability of the UE or BS is low, such as when the number of panels on which the UE or BS performs LBT is 1 or the number of panels on which the UE or BS can simultaneously perform LBT is 1, the construction cost or implementation problem (or implementation difficulty) of the UE or BS may not be high because the UE or BS may perform D-LBT on one or more Tx beams.

[0436] In addition, as in (3) of Example #2-1 and (3) of Example #2-2, performing D-LBT using multiple LBT beams each covering the interference range of one or more Tx beams can improve the transmission efficiency of the UE or BS.

[0437] For example, when the transmission of DL / UL signals / channels is scheduled one by one for each of Tx beams 1 to Tx beam 4, if the D-LBT for LBT beam 2 corresponding to Tx beam 2 fails and the D-LBT for LBT beam 1, LBT beam 3 and LBT beam 4 corresponding to Tx beam 1, Tx beam 3 and Tx beam 4 succeeds, only the transmission of the DL / UL signals / channels scheduled for Tx beam 2 can be discarded, and the DL / UL signals / channels scheduled for Tx beam 1, Tx beam 3 and Tx beam 4 can be sent, thereby improving transmission efficiency and resource utilization efficiency.

[0438] [Proposed Method #3]

[0439] When a BS or UE always performs LBT in units of LBT bandwidth before transmission, an LBT bandwidth (hereinafter referred to as 'LBT-BW') considering a relationship with BWP / CC may be configured.

[0440] 1. Example #3-1

[0441] The LBT-BW region associated with the corresponding BWP / CC for each BWP / CC can be configured. That is, the LBT-BW region used for LBT transmitted for the corresponding BWP / CC can be configured. For example, the starting RB and bandwidth (BW) of the LBT-BW region can be configured. Alternatively, the starting RB and ending RB of the LBT-BW region can be configured. Alternatively, the starting RB of the LBT region and the number of RBs in the LBT-BW region can be configured.

[0442] 2. Example #3-2

[0443] Each LBT-BW or LBT-BW set can be configured without a separate association with a BWP / CC. For example, if the starting RB and BW of an LBT-BW area and the number of LBT-BWs N are configured, N (contiguous) LBT-BWs with a BW size from the starting RB can be configured. In this case, the ending RB or the number of RBs can be configured instead of the BW. For example, the starting RB and ending RB of an LBT-BW area and the number of LBT-BWs N can be configured, or the starting RB, the number of RBs, and the number of LBT-BWs N of an LBT-BW area can be configured.

[0444] 3. Example #3-3

[0445] Only a minimum LBT-BW (eg, Min-BW) value may be configured, and the actual LBT-BW may be determined based on the relationship with the BWP / CC size.

[0446] For example, for a BWP / CC smaller than min-BW, the actual LBT-BW can be configured as min-BW (i.e., LBT-BW=min-BW). For a BWP / CC larger than min-BW, the LBT-BW can be configured as BWP / CC (i.e., LBT-BW=BWP / CC).

[0447] 4. Example #3-4

[0448] The BS may configure an LBT BW index for each CC pre-configured as carrier aggregation (CA) relative to a UE for which CCs of various BW sizes are configured as CA. The BS may perform LBT according to the LBT BW index indicated during UL scheduling.

[0449] The relationship between BWP / CC and LBT-BW can have a structure where multiple (narrow) LBT-BWs are included in one (wide) BWP / CC, as in the conventional Rel-16 NR-U, or conversely, a structure where one (wide) BWP / CC or multiple (wide) BWP / CCs are included in a single LBT-BW. One BWP / CC can be configured to be confined to only one LBT-BW. In other words, a configuration where one BWP / CC spans multiple LBT-BWs can be excluded.

[0450] Hereinafter, [Proposed Method #3] will be described in detail.

[0451] In Rel-16 NR-U, considering the coexistence of the requirements of the nominal channel BW such as defined in the 5-GHz band regulations (e.g., ETSI EN 302 893) with the incumbent systems (e.g., 802.11 series Wi-Fi systems), it has been considered to always use 20 MHz as the unit LBT-BW of the basic unit of LBT.

[0452] However, in FR4 (e.g., the 60 GHz frequency band) newly considered in Rel-17, the definition of the unit LBT-BW to be performed before the BS and UE perform transmission is vague when considering regulations (e.g., ETSI EN 302 567) and incumbent systems (e.g., WiGig). Therefore, it is necessary to define LBT-BW within which the BS and UE can effectively perform LBT before transmission and send and receive DL / UL signals / channels in the FR4 band.

[0453] For example, if LBT-BW is not defined, the BS or UE may perform LBT on the total channel BW or BWP BW for transmission, or perform as much LBT as the transmission BW for transmission (e.g., from the lowest RB to the highest RB used for transmission).

[0454] In the case of multi-carrier transmission with intra-band CA configured, multiple LBT operations can be performed separately for each channel BW. Alternatively, LBT can be performed only as many times as the transmission BW for each CC. Therefore, it is necessary to configure LBT-BW considering the relationship between LBT-BW and BWP / CC. This eliminates the problem of unequal LBT opportunities that may occur when the BS and UE perform LBT based on unnecessarily wide BWs or when the UE and BS perform LBT using different BW sizes, and enables efficient LBT and transmission / reception.

[0455] Embodiment #3-1 is a method for configuring an LBT-BW region associated with each BWP / CC, that is, a method for configuring an LBT-BW region for LBT transmission for the corresponding BWP / CC. For example, the starting RB and BW size of the LBT-BW associated with a specific BWP / CC can be configured.

[0456] Alternatively, the starting RB and ending RB of the LBT-BW associated with a specific BWP / CC may be configured. Alternatively, the starting RB and the number of RBs of the LBT-BW associated with a specific BWP / CC may be configured.

[0457] Example #3-2 is a method for configuring each LBT-BW or LBT-BW set without a separate association with a BWP / CC. For example, if the starting RB and BW of the LBT-BW and the number of LBT-BWs are configured, N (contiguous) LBT-BWs with a BW size starting from the starting RB can be configured. In this case, the ending RB or the number of RBs can be configured instead of the BW. For example, the starting RB and ending RB of the LBT-BW and the number of LBT-BWs can be configured, or the starting RB of the LBT-BW, the number of RBs of the LBT-BW, and the number N of LBT-BWs can be configured.

[0458] Embodiment #3-3 may configure only the minimum LBT-BW (e.g., min-BW) value and determine the actual LBT-BW based on the relationship with the BWP / CC size. For example, for a BWP / CC smaller than the min-BW, the actual LBT-BW may be configured to be the min-BW (i.e., LBT-BW = min-BW). For a BWP / CC larger than the min-BW, the LBT-BW may be configured to be the corresponding BWP / CC (i.e., LBT-BW = BWP / CC).

[0459] For example, if LBT-BW=max(min-BW, BWP BW or CC BW), the size of LBT-BW may be determined as follows.

[0460] 1) For BWP / CC>min-BW, LBT-BW=BWP / CC

[0461] 2) For BWP / CC <min-BW,LBT-BW=min-BW

[0462] 3) For BWP / CC=min-BW, LBT-BW=BWP / CC=min-BW

[0463] Here, in the case of 2), the starting position or center position of min-BW can be configured to be equal to the starting position or center position of BWP / CC. Alternatively, the position of LBT-BW can be configured by setting the relative value of the starting position or center position of min-BW and the starting position or center position of BWP / CC.

[0464] As an example of embodiment #3-4, if three CCs of {CC1 of 400M in size, CC2 of 200M in size, CC3 of 200M in size} are configured as CA for the UE, and if the LBT-BW indices corresponding to CC1, CC2, and CC3 are respectively configured as {0, 1, 1}, then since only {CC1} is included in LBT-BW index 0, LBT can be performed based on an LBT-BW of 400MHz. In addition, since LBT BW index 1 includes {CC2, CC3}, LBT can be performed based on an LBT-BW of 400MHz obtained by adding CC2 and CC3.

[0465] As another example, if LBT BW index = {0, 0, 1}, 600 MHz LBT may be performed because {CC1, CC2} are included in LBT-BW index 0. 200 MHz LBT may be performed because only {CC3} is included in LBT-BW index 1.

[0466] As another example, it is possible to configure a start RB and an end RB for each LBT-BW index, and to allow one or more CCs to be completely included in the RB range configured for each LBT-BW index. In other words, the start RB and / or the end RB can be defined to always be configured at the CC BW boundary. In other words, it is possible to specify that the start RB and / or the end RB are not configured to overlap only a portion of the CC BW within the CC BW. As an alternative to the above example, the start RB and the number of RBs can be configured for each LBT-BW index.

[0467] A BWP / CC is configured to be confined to only one LBT-BW. Therefore, configurations where a BWP / CC spans multiple LBT-BWs are excluded. Even if the LBT-BW configured for the UE is larger than the BWP / CC size, LBT should always be performed within the LBT-BW size, such as through CA.

[0468] The ED threshold for performing LBT can be expressed as a function of the output power of the UE or BS and the size of the operating channel BW. The relationship between these two factors and the ED threshold can be expressed as [Equation 1].

[0469] [Equation 1]

[0470]

[0471] Here, the operating channel BW may be the size of the BW of LBT performed by the UE or BS, or the BWP of the actual transmission or the BW size of the transmission BW. However, in the 60 GHz band, since D-LBT, which performs LBT only in a specific target Tx direction, is considered instead of O-LBT performed in the 5 GHz band, the ED threshold may be configured differently depending on the relationship between the sensing beam and the Tx beam (e.g., beam correspondence).

[0472] The UE's capability for the above-mentioned beam correspondence is defined in Section 6.6 of TS 38.101-2, and the BS may differently configure the ED threshold for performing D-LBT according to the UE's beam correspondence capability as follows.

[0473] 1) Even without BM (such as UL beam sweeping and UL beam indication by the network), a UE that supports beamCorrespondenceWithoutUL-BeamSweeping can also establish beam correspondence well. In this case, even without BM, the UE should meet requirements such as minimum peak EIRP and spherical coverage.

[0474] 2) UEs that do not support beamCorrespondenceWithoutUL-BeamSweepin can meet requirements such as minimum peak EIRP and spherical coverage through the BM process. In addition, even without the BM process, the UE can meet the relaxed requirements of about 3dB.

[0475] [Proposed Method #4]

[0476] The UE may adjust the ED threshold for performing LBT according to whether the UE supports beam correspondence (BC) and whether the BM process is performed.

[0477] 1. Example #4-1

[0478] In the case that the UE supports beamCorrespondenceWithoutUL-BeamSweeping, the ED threshold may be calculated considering only the output power and the operating channel BW.

[0479] 2. Example #4-2

[0480] In the case of a UE that does not support beamCorrespondenceWithoutUL-BeamSweeping, at least one of the following methods may be used to calculate the ED threshold.

[0481] (1) An additional penalty value X dB explicitly configured / indicated by the BS may be applied to the ED threshold calculated based on the output power and the operating channel BW according to [Equation 1]. For example, the ED threshold may be reduced by applying the penalty value.

[0482] (2) If there is no penalty of X dB explicitly configured by the BS, then X = 3 dB may be applied by default.

[0483] If additional configuration is received from the BS, the same ED threshold as in embodiment #4-1 with BC capability may be used without penalty.

[0484] (3) Depending on whether the UE is configured with SRS for BM, a penalty may be applied implicitly.

[0485] In the case where SRS for BM is not configured, a penalty of 3 dB may be added to the ED threshold calculated based on the output power and the operating channel BW according to [Equation 1], so that LBT may be performed using a lower ED threshold.

[0486] Alternatively, the same ED threshold as in embodiment #4-1 with BC-related capability may be used when only SRS is configured with repetition set to “off” or after the configured SRS is sent at least N times (assuming the BM process has been performed).

[0487] (4) Alternatively, even if the UE does not support beamCorrespondenceWithoutUL-BeamSweeping, X=0 dB may be applied as the default X value for calculating the ED threshold (until a penalty of X dB is explicitly configured by the BS). This is because no particular problem occurs even if the ED threshold is not configured differently depending on whether beamCorrespondenceWithoutUL-BeamSweeping is supported, depending on the number of UEs and the number of beams operating in the cell.

[0488] [Proposed method #4] will be described in detail.

[0489] As described above, when establishing a BC between a DL beam and an UL beam, the process for determining a DL beam pair or the BM process for determining a UL beam pair can be omitted. Establishing a BC may mean that it can be assumed that the BS Tx beam and the BS Rx beam coincide with each other, and that the UE Tx beam and the UE Rx beam coincide with each other in communications between the BS and the UE. Here, the BS Tx beam and the BS Rx beam may refer to the DL Tx beam and the DL Rx beam, respectively, and the UE Tx beam and the UE Rx beam may refer to the UL Tx beam and the UL Rx beam, respectively.

[0490] In the case of performing D-LBT by the Tx end, taking into account the Tx beam direction in which the BS or UE expects to perform transmission, the energy in the area that suffers interference when transmitting the Tx beam (for example, an area equal to or greater than the area where the Tx beam affects interference) can be measured through the Rx beam. Then, it is possible to determine whether the channel is idle or busy by comparing the measured energy with the ED threshold. In addition, it is possible to determine whether to perform transmission based on the determination of whether the channel is idle or busy. Therefore, when performing LBT through the Rx beam, the ED threshold can be adjusted according to the BC and reflected when determining whether the channel is idle or busy.

[0491] The BC-based ED threshold adjustment may be changed depending on whether the UE supports beamCorrespondenceWithoutUL-BeamSweeping and whether the BM procedure is performed. If the UE supports beamCorrespondenceWithoutUL-BeamSweeping, the ED threshold may be calculated using [Equation 1] by considering only the output power and operating channel BW without a separate penalty, and the ED threshold may be applied to LBT.

[0492] In the case where the UE does not support beamCorrespondenceWithoutUL-BeamSweeping, an additional penalty of XdB explicitly configured / indicated by the BS can be applied to the ED threshold calculated using the output power and operating channel BW of [Equation 1]. For example, the ED threshold can be reduced by applying the penalty value. Alternatively, if there is no penalty value of XdB configured by the BS, X = 3dB can be applied as a default. However, if an additional configuration is received from the BS, the same ED threshold as in embodiment #4-1 with BC capability can be used without penalty.

[0493] As another example, a penalty may be implicitly applied depending on whether the UE is configured with SRS for BM.

[0494] When SRS for BM is not configured, a 3dB penalty may always be applied to the ED threshold calculated based on the output power and the operating channel BW of [Equation 1], so that LBT may be performed using a lower obtained ED threshold.

[0495] If only SRS for BM is configured or after the configured SRS is transmitted at least N times (assuming that the BM procedure has been performed), the same ED threshold as in embodiment #4-1 with BC-related capability value may be used.

[0496] Alternatively, even if the UE does not support beamCorrespondenceWithoutUL-BeamSweeping, X = 0 dB may be applied as the default X value for calculating the ED threshold (until a penalty of X dB is explicitly configured by the BS). This is because even if the ED threshold is not configured differently depending on whether beamCorrespondenceWithoutUL-BeamSweeping is supported, no particular problem occurs, depending on the number of beams and the number of UEs operating in the cell.

[0497] The various descriptions, functions, processes, proposals, methods and / or operational flowcharts of the present disclosure described herein may be applied to, but not limited to, various fields requiring wireless communication / connectivity between devices (e.g., 5G).

[0498] More specific examples will be described below with reference to the accompanying drawings. In the following drawings / descriptions, unless otherwise specified, similar reference numerals represent identical or corresponding hardware blocks, software blocks or functional blocks.

[0499] Figure 26 The diagram shows a communication system 1 applied to the present disclosure.

[0500] refer to Figure 26, the communication system 1 applied to the present disclosure includes wireless devices, BS and network. Wireless devices are devices that perform communication using radio access technology (RAT) (e.g., 5G NR (or new RAT) or LTE), also known as communication / radio / 5G devices. Wireless devices may include, but are not limited to, robots 100a, vehicles 100b-1 and 100b-2, extended reality (XR) devices 100c, handheld devices 100d, home appliances 100e, IoT devices 100f, and artificial intelligence (AI) devices / servers 400. For example, vehicles may include vehicles with wireless communication capabilities, autonomous vehicles, and vehicles capable of performing vehicle-to-vehicle (V2V) communication. Here, vehicles may include unmanned aerial vehicles (UAVs) (e.g., drones). XR devices may include augmented reality (AR) / virtual reality (VR) / mixed reality (MR) devices and may be implemented in the form of head-mounted devices (HMDs), head-up displays (HUDs) installed in vehicles, televisions (TVs), smartphones, computers, wearable devices, home appliances, digital signage, vehicles, robots, etc. Handheld devices may include smartphones, smartpads, wearable devices (e.g., smartwatches or smart glasses), and computers (e.g., laptops). Home appliances may include televisions, refrigerators, washing machines, and the like. IoT devices may include sensors, smart meters, and the like. For example, the BS and network may be implemented as wireless devices, and a specific wireless device 200a may serve as a BS / network node for other wireless devices.

[0501] Wireless devices 100a to 100f can be connected to a network 300 via a BS 200. AI technology can be applied to wireless devices 100a to 100f, and wireless devices 100a to 100f can be connected to an AI server 400 via the network 300. The network 300 can be configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. Although wireless devices 100a to 100f can communicate with each other via the BS 200 / network 300, wireless devices 100a to 100f can perform direct communication (e.g., sidelink communication) with each other without the intervention of the BS / network. For example, vehicles 100b-1 and 100b-2 can perform direct communication (e.g., V2V / Vehicle-to-Everything (V2X) communication). IoT devices (e.g., sensors) can perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.

[0502] Wireless communications / connections 150a, 150b, and 150c may be established between wireless devices 100a to 100f and BS 200, and between BSs 200. Wireless communications / connections may be established via various RATs (e.g., 5G NR), such as UL / DL communication 150a, sidelink communication 150b (or D2D communication), or inter-BS communication 150c (e.g., relay or integrated access backhaul (IAB)). Wireless signals may be transmitted and received between wireless devices, between wireless devices and BSs, and between BSs via the wireless communications / connections 150a, 150b, and 150c. For example, signals may be transmitted and received on various physical channels via the wireless communications / connections 150a, 150b, and 150c. To this end, at least a portion of various configuration information configuration processes, various signal processing processes (e.g., channel coding / decoding, modulation / demodulation, and resource mapping / demapping), and resource allocation processes for transmitting / receiving wireless signals may be performed based on various suggestions of the present disclosure.

[0503] Figure 27 The diagram illustrates a wireless device suitable for use with the present disclosure.

[0504] refer to Figure 27 , the first wireless device 100 and the second wireless device 200 can transmit wireless signals via various RATs (e.g., LTE and NR). {The first wireless device 100 and the second wireless device 200} may correspond to Figure 26 {wireless device 100x and BS 200} and / or {wireless device 100x and wireless device 100x}.

[0505] The first wireless device 100 may include one or more processors 102 and one or more memories 104, and may further include one or more transceivers 106 and / or one or more antennas 108. The processor 102 may control the memory 104 and / or the transceiver 106 and may be configured to implement the descriptions, functions, processes, proposals, methods, and / or operational flow charts disclosed in this document. For example, the processor 102 may process information within the memory 104 to generate first information / signals, and then transmit a wireless signal including the first information / signals through the transceiver 106. The processor 102 may receive a wireless signal including second information / signals through the transceiver 106, and then store information obtained by processing the second information / signals in the memory 104. The memory 104 may be connected to the processor 102 and store a plurality of pieces of information related to the operation of the processor 102. For example, the memory 104 may store software code including instructions for executing some or all of the processes controlled by the processor 102 or for executing the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document. The processor 102 and the memory 104 may be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver 106 may be connected to the processor 102 and transmit and / or receive wireless signals via one or more 108. Each of the transceivers 106 may include a transmitter and / or a receiver. The transceiver 106 may be used interchangeably with a radio frequency (RF) unit. In the present disclosure, a wireless device may be a communication modem / circuit / chip.

[0506] Specifically, instructions and / or operations controlled by the processor 102 of the first wireless device 100 and stored in the memory 104 of the first wireless device 100 according to an embodiment of the present disclosure will be described.

[0507] Although the following operations are described based on the control operations of the processor 102 in terms of the processor 102, software codes for executing such operations may be stored in the memory 104. For example, in the present disclosure, at least one memory 104 may be a computer-readable storage medium and may store instructions or programs. When the instructions or programs are executed, at least one processor operatively connected to the at least one memory may execute operations related to the following operations according to embodiments or implementations of the present disclosure.

[0508] Specifically, the processor 102 may obtain an ED threshold value for energy sensing. For example, the processor 102 may obtain the ED threshold value based on at least one of [Proposed Method #1], [Proposed Method #2], or [Proposed Method #4]. However, the processor may also obtain the ED threshold value using existing technologies or methods other than the methods proposed in the present disclosure.

[0509] The processor 102 may obtain the LBT-BW. For example, the processor 102 may obtain the LBT-BW based on [Proposed Method #3]. However, the method for obtaining the LBT-BW based on [Proposed Method #3] may be omitted. If the method for obtaining the LBT-BW based on [Proposed Method #3] is omitted, the processor 102 may perform LBT based on the LBT-BW (e.g., 20 MHz) according to existing techniques, or perform LBT using the configured BWP size as the LBT-BW unit.

[0510] Processor 102 may perform LBT based on the obtained ED threshold and / or LBT-BW. Furthermore, if LBT is successful, processor 102 may control transceiver 106 to transmit an UL signal to the BS. For example, processor 102 may perform LBT on the multiplexed Tx beams based on [Proposed Method #2] and control transceiver 106 to transmit an UL signal.

[0511] The processor 102 may control the transceiver 106 to receive a DL signal from the BS.

[0512] The second wireless device 200 may include one or more processors 202 and one or more memories 204, and may further include one or more transceivers 206 and / or one or more antennas 208. The processor 202 may control the memory 204 and / or the transceiver 206 and may be configured to implement the descriptions, functions, processes, proposals, methods, and / or operational flow charts disclosed in this document. For example, the processor 202 may process the information in the memory 204 to generate third information / signals, and then transmit a wireless signal including the third information / signals through the transceiver 206. The processor 202 may receive a wireless signal including fourth information / signals through the transceiver 106, and then store information obtained by processing the fourth information / signals in the memory 204. The memory 204 may be connected to the processor 202 and store various information related to the operation of the processor 202. For example, the memory 204 may store software code including instructions for executing some or all of the processes controlled by the processor 202 or for executing the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document. The processor 202 and the memory 204 may be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver 206 may be connected to the processor 202 and transmit and / or receive wireless signals via one or more antennas 208. Each of the transceivers 206 may include a transmitter and / or a receiver. The transceiver 206 may be used interchangeably with an RF unit. In the present disclosure, a wireless device may be a communication modem / circuit / chip.

[0513] Specifically, instructions and / or operations controlled by the processor 202 of the second wireless device 200 and stored in the memory 204 of the second wireless device 200 according to an embodiment of the present disclosure will be described.

[0514] Although the following operations are described based on the control operations of the processor 202 in terms of the processor 202, software codes for executing such operations may be stored in the memory 204. For example, in the present disclosure, the at least one memory 204 may be a computer-readable storage medium and may store instructions or programs. When the instructions or programs are executed, the at least one processor operatively connected to the at least one memory may execute operations related to the following operations according to embodiments or implementations of the present disclosure.

[0515] Specifically, the processor 202 may obtain an ED threshold value for energy sensing. For example, the processor 202 may obtain the ED threshold value based on at least one of [Proposed Method #1], [Proposed Method #2], or [Proposed Method #4]. However, the processor 202 may also obtain the ED threshold value using existing technologies or methods other than the methods proposed in the present disclosure.

[0516] The processor 202 may configure the LBT-BW. For example, the processor 202 may configure the LBT-BW based on [Proposed Method #3]. However, the method for configuring the LBT-BW according to [Proposed Method #3] may be omitted. If the method for configuring the LBT-BW according to [Proposed Method #3] is omitted, the processor 202 may perform LBT based on the LBT-BW (e.g., 20 MHz) according to existing techniques, or perform LBT using the configured BWP size as the LBT-BW unit.

[0517] Processor 202 may perform LBT based on the obtained ED threshold and / or LBT-BW (S2205). Furthermore, if LBT is successful, processor 202 may control transceiver 206 to transmit a DL signal to the UE. For example, processor 202 may perform LBT on the multiplexed Tx beams based on [Proposed Method #2] and control transceiver 206 to transmit a DL signal.

[0518] The processor 202 may control the transceiver 206 to receive a UL signal from the UE.

[0519] The hardware elements of the wireless devices 100 and 200 will now be described in more detail. One or more protocol layers may be implemented by, but are not limited to, one or more processors 102 and 202. For example, the one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as physical (PHY), medium access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), RRC, and service data adaptation protocol (SDAP)). The one or more processors 102 and 202 may generate one or more protocol data units (PDUs) and / or one or more service data units (SDUs) according to the descriptions, functions, processes, proposals, methods, and / or operational flow charts disclosed in this document. The one or more processors 102 and 202 may generate messages, control information, data, or information according to the descriptions, functions, processes, proposals, methods, and / or operational flow charts disclosed in this document and provide the messages, control information, data, or information to the one or more transceivers 106 and 206. The one or more processors 102 and 202 may generate a signal (e.g., a baseband signal) including a PDU, SDU, message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operational flow charts disclosed in this document and provide the generated signal to the one or more transceivers 106 and 206. The one or more processors 102 and 202 may receive a signal (e.g., a baseband signal) from the one or more transceivers 106 and 206 and obtain the PDU, SDU, message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operational flow charts disclosed in this document.

[0520] The one or more processors 102 and 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The one or more processors 102 and 202 may be implemented using hardware, firmware, software, or a combination thereof. For example, one or more application-specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field-programmable gate arrays (FPGAs) may be included in the one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be configured to include modules, processes, or functions. The firmware or software configured to execute the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document may be included in the one or more processors 102 and 202, or may be stored in one or more memories 104 and executed by the one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document may be implemented using firmware or software in the form of code, instructions, and / or instruction sets.

[0521] One or more memories 104 and 204 can be connected to one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, codes, instructions and / or commands. One or more memories 104 and 204 can be configured to include read-only memory (ROM), random access memory (RAM), electrically erasable programmable read-only memory (EPROM), flash memory, hard drive, registers, cache memory, computer-readable storage media and / or combinations thereof. One or more memories 104 and 204 can be located inside and / or outside one or more processors 102 and 202. One or more memories 104 and 204 can be connected to one or more processors 102 and 202 via various technologies such as wired or wireless connections.

[0522] One or more transceivers 106 and 206 may transmit user data, control information, and / or wireless signals / channels described in the methods and / or operational flowcharts of this document to one or more other devices. One or more transceivers 106 and 206 may receive user data, control information, and / or wireless signals / channels described in the description, the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document from one or more other devices. For example, one or more transceivers 106 and 206 may be connected to one or more processors 102 and 202 and transmit and receive wireless signals. For example, one or more processors 102 and 202 may control one or more transceivers 106 and 206 to transmit user data, control information, or wireless signals to one or more other devices. One or more processors 102 and 202 may control one or more transceivers 106 and 206 to receive user data, control information, or wireless signals from one or more other devices. One or more transceivers 106 and 206 can be connected to one or more antennas 108 and 208, and one or more transceivers 106 and 206 can be configured to transmit and receive user data, control information, and / or wireless signals / channels mentioned in the descriptions, functions, processes, and recommendations disclosed in this document through one or more antennas 108 and 208. In this document, one or more antennas can be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106 and 206 can convert received wireless signals / channels, etc. from RF band signals to baseband signals so that the received user data, control information, and wireless signals / channels can be processed using one or more processors 102 and 202. One or more transceivers 106 and 206 can convert user data, control information, wireless signals / channels processed using one or more processors 102 and 202 from baseband signals to RF band signals. To this end, one or more transceivers 106 and 206 can include (analog) oscillators and / or filters.

[0523] Figure 28 The diagram illustrates a vehicle or autonomous vehicle applicable to the present disclosure. The vehicle or autonomous vehicle may be implemented as a mobile robot, a car, a train, a manned / unmanned aerial vehicle (AV), a ship, and the like.

[0524] refer to Figure 28 The vehicle or autonomous driving vehicle 100 may include an antenna unit 108, a communication unit 110, a control unit 120, a drive unit 140a, a power supply unit 140b, a sensor unit 140c, and an autonomous driving unit 140d. The antenna unit 108 may be configured as part of the communication unit 110.

[0525] The communication unit 110 can send and receive signals (e.g., data and control signals) to and from external devices such as other vehicles, base stations (e.g., gNBs and roadside units), and servers. The control unit 120 can perform various operations by controlling components of the vehicle or autonomous vehicle 100. The control unit 120 may include an ECU. The drive unit 140a can enable the vehicle or autonomous vehicle 100 to navigate a road. The drive unit 140a may include an engine, a motor, a powertrain, wheels, brakes, a steering system, and the like. The power supply unit 140b can supply power to the vehicle or autonomous vehicle 100 and may include wired / wireless charging circuits, a battery, and the like. The sensor unit 140c can acquire information regarding vehicle status, surrounding environment, user information, and the like. The sensor unit 140 c may include an inertial measurement unit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor, a slope sensor, a weight sensor, a heading sensor, a location module, a vehicle forward / backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, an illumination sensor, a pedal position sensor, etc. The autonomous driving unit 140 d may implement a technology for maintaining a lane in which the vehicle is driving, a technology for automatically adjusting a speed such as adaptive cruise control, a technology for autonomously driving along a determined path, a technology for driving by automatically setting a path if a destination is set, etc.

[0526] For example, the communication unit 110 can receive map data, traffic information data, and the like from an external server. The autonomous driving unit 140d can generate an autonomous driving route and driving plan based on the obtained data. The control unit 120 can control the drive unit 140a so that the vehicle or autonomous driving vehicle 100 moves along the autonomous driving route according to the driving plan (e.g., speed / direction control). During autonomous driving, the communication unit 110 can periodically obtain recent traffic information data from the external server and can obtain surrounding traffic information data from neighboring vehicles. During autonomous driving, the sensor unit 140c can obtain information regarding vehicle status and / or surrounding environment information. The autonomous driving unit 140d can update the autonomous driving route and driving plan based on the newly obtained data / information. The communication unit 110 can transmit information regarding the vehicle's location, autonomous driving route, and / or driving plan to the external server. The external server can use AI technology, etc., based on the information collected from the vehicle or autonomous driving vehicle to predict traffic information data and provide the predicted traffic information data to the vehicle or autonomous driving vehicle.

[0527] The embodiments of the present disclosure described below are combinations of elements and features of the present disclosure. Unless otherwise stated, these elements or features may be considered as optional. Each element or feature may be practiced without being combined with other elements or features. In addition, the embodiments of the present disclosure may be constructed by combining a portion of the elements and / or features. The order of operations described in the embodiments of the present disclosure may be rearranged. Some configurations of any one embodiment may be included in another embodiment and may be replaced by the corresponding configurations of another embodiment. It will be apparent to those skilled in the art that claims that are not explicitly referenced to each other in the appended claims may be presented in combination as embodiments of the present disclosure, or may be included as new claims through subsequent amendments after filing the application.

[0528] In the present disclosure, in some cases, specific operations described as being performed by a base station (BS) may be performed by an upper node of the BS. That is, it is apparent that in a network consisting of multiple network nodes including a BS, various operations performed for communication with an MS may be performed by the BS or network nodes other than the BS. The term "BS" may be replaced with terms such as "fixed station," "Node B," "enhanced Node B (eNodeB or eNB)," and "access point."

[0529] Those skilled in the art will understand that the present disclosure can be implemented in other specific ways than those set forth herein without departing from the spirit and essential characteristics of the present disclosure. Therefore, the above embodiments are to be construed in all respects as illustrative and not restrictive. The scope of the present disclosure is to be determined by the appended claims and their legal equivalents, not by the above description, and all changes coming within the meaning and equivalent range of the appended claims are intended to be embraced therein.

[0530] Industrial Applicability

[0531] Although the above-mentioned method and apparatus for performing CAP have been described based on an example applied to a 5G NR system, the method and apparatus are applicable to various wireless communication systems in addition to the 5G NR system.

Claims

1. A method by a user equipment (UE), comprising: performing a listen-before-talk (LBT) based on at least one LBT beam; as well as transmitting an uplink signal through a transmission beam based on at least one channel for the LBT being sensed as idle, wherein the at least one LBT beam covers the transmission beam that is time division multiplexed (TDM), wherein the UE performs additional LBT before switching between the transmission beams, wherein the additional LBT is performed using one of a first type LBT or a second type LBT based on a time required to switch between the transmission beams, and The first type LBT is a random backoff-based LBT, and the second type LBT is a non-random backoff-based LBT.

2. The method according to claim 1, wherein The additional LBT is performed using the second type LBT based on a time required to switch between transmission beams being less than or equal to a certain threshold.

3. The method according to claim 1, wherein The additional LBT is performed using the first type of LBT based on a time required to switch between transmission beams exceeding a certain threshold.

4. The method according to claim 1, wherein The at least one LBT beam is a single LBT beam covering all of the transmission beams.

5. The method according to claim 1, wherein The at least one LBT beam includes a plurality of LBT beams, and each of the plurality of LBT beams covers each of the transmission beams.

6. A user equipment (UE), comprising: at least one transceiver; at least one processor; as well as at least one memory operatively connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations comprising: performing a listen-before-talk (LBT) based on at least one LBT beam; and transmitting, by the at least one transceiver, an uplink signal through a transmission beam based on at least one channel for the LBT being sensed as idle, and wherein the at least one LBT beam covers the transmission beam that is time division multiplexed (TDM), wherein the UE performs additional LBT before switching between the transmission beams, wherein the additional LBT is performed using one of a first type of LBT or a second type of LBT based on a time required to switch between the transmission beams, and The first type LBT is a random backoff-based LBT, and the second type LBT is a non-random backoff-based LBT.

7. The UE according to claim 6, wherein: The additional LBT is performed using the second type LBT based on a time required to switch between transmission beams being less than or equal to a certain threshold.

8. The UE according to claim 6, wherein: The additional LBT is performed using the first type of LBT based on a time required to switch between transmission beams exceeding a certain threshold.

9. The UE according to claim 6, wherein: The at least one LBT beam is a single LBT beam covering all of the transmission beams.

10. The UE according to claim 6, wherein: The at least one LBT beam includes a plurality of LBT beams, and each of the plurality of LBT beams covers each of the transmission beams.

11. A device comprising: at least one processor; as well as at least one memory operatively connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations comprising: performing a listen-before-talk (LBT) based on at least one LBT beam; and transmitting an uplink signal through a transmission beam based on at least one channel for the LBT being sensed as idle, and wherein the at least one LBT beam covers the transmission beam that is time division multiplexed (TDM), wherein additional LBT is performed before switching between said transmission beams, wherein the additional LBT is performed using one of a first type LBT or a second type LBT based on a time required to switch between the transmission beams, and The first type LBT is a random backoff-based LBT, and the second type LBT is a non-random backoff-based LBT.

12. A computer-readable storage medium comprising at least one computer program, the at least one computer program causing at least one processor to perform operations comprising: performing a listen-before-talk (LBT) based on at least one LBT beam; as well as transmitting an uplink signal through a transmission beam based on at least one channel for the LBT being sensed as idle, and wherein the at least one LBT beam covers the transmission beam that is time division multiplexed (TDM), wherein additional LBT is performed before switching between said transmission beams, wherein the additional LBT is performed using one of a first type LBT or a second type LBT based on a time required to switch between the transmission beams, and The first type LBT is a random backoff-based LBT, and the second type LBT is a non-random backoff-based LBT.

13. A method by a base station, comprising: performing a listen-before-talk (LBT) based on at least one LBT beam; as well as transmitting a downlink signal through a transmission beam based on at least one channel for the LBT being sensed as idle, wherein the at least one LBT beam covers the transmission beam that is time division multiplexed (TDM), wherein additional LBT is performed before switching between said transmission beams, wherein the additional LBT is performed using one of a first type LBT or a second type LBT based on a time required to switch between the transmission beams, and The first type LBT is a random backoff-based LBT, and the second type LBT is a non-random backoff-based LBT.

14. A base station, comprising: at least one transceiver; at least one processor; as well as at least one memory operatively connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations comprising: performing a listen-before-talk (LBT) based on at least one LBT beam; and transmitting, by at least one transceiver, a downlink signal through a transmission beam based on at least one channel for the LBT being sensed as idle, and wherein the at least one LBT beam covers the transmission beam that is time division multiplexed (TDM), wherein additional LBT is performed before switching between said transmission beams, wherein the additional LBT is performed using one of a first type LBT or a second type LBT based on a time required to switch between the transmission beams, and The first type LBT is a random backoff-based LBT, and the second type LBT is a non-random backoff-based LBT.

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