Methods and apparatus for performing uplink / downlink transmission in a wireless communication system

Abstract

A method for receiving downlink transmissions by a terminal includes the following steps: performing uplink transmissions to a base station related to channel occupancy shared between the base station and the terminal; and receiving downlink transmissions from the base station after a gap from the point in time when the uplink transmissions have been received from the base station, wherein the downlink transmissions are performed based on channel access performed by the base station, channel access is performed based on the gap, and information included in the downlink transmissions and resources used to perform the downlink transmissions are determined based on whether the base station has configured an energy detection threshold for channel occupancy for the terminal.

Description

Technical Field

[0001] This specification relates to a wireless communication system, and more particularly to a method and apparatus for performing uplink / downlink transmissions. Background Technology

[0002] Following the commercialization of fourth-generation (4G) communication systems, efforts are underway to develop new fifth-generation (5G) communication systems to meet the increasing demand for wireless data services. 5G communication systems are also referred to as post-4G network communication systems, post-LTE systems, or new radio (NR) systems. To achieve high data transmission rates, 5G communication systems include systems operating in 6 GHz or higher millimeter-wave (mmWave) frequency bands, and systems operating in 6 GHz or lower frequency bands are also being considered to ensure coverage. The implementation methods in base stations and terminals are being considered.

[0003] The 3GPP (3rd Generation Partnership Project) NR system improves network spectral efficiency and enables communication providers to offer more data and voice services within a given bandwidth. Therefore, the 3GPP NR system is designed to meet the demand for high-speed data and media transmission in addition to supporting a large volume of voice calls. The advantages of the NR system include higher throughput and lower latency on the same platform, support for both Frequency Division Duplex (FDD) and Time Division Duplex (TDD), and low operating costs due to the enhanced end-user environment and simple architecture.

[0004] For more efficient data processing, the dynamic TDD of the NR system can use a method to change the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols that can be used in the uplink and downlink based on the data traffic direction of cell users. For example, when the downlink traffic of a cell is greater than the uplink traffic, the base station can allocate multiple downlink OFDM symbols to a time slot (or subframe). Information about the time slot configuration should be sent to the terminal.

[0005] To mitigate path loss and increase transmission distance in the mmWave band, beamforming, massive MIMO, full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, hybrid beamforming combining analog and digital beamforming, and massive MIMO technologies are discussed in 5G communication systems. Furthermore, for network improvements, technologies related to evolved small cells, advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device-to-device (D2D) communication, vehicle-to-everything (V2X) communication, wireless backhaul, non-terrestrial network communication (NTN), mobile networks, cooperative communication, coordinated multipoint (CoMP), and interference cancellation are being developed in 5G communication systems. Additionally, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) are being developed as advanced coding and modulation (ACM) schemes, while filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) are being developed as advanced connectivity technologies.

[0006] Simultaneously, within the human-centric network of interconnected networks where humans generate and consume information, the Internet has evolved into the Internet of Things (IoT) network, which exchanges information between distributed components such as objects. The Internet of Everything (IoE) technology, combining IoT with big data processing through connections to cloud servers, is also emerging. Realizing IoT requires technological elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology. This has led to the recent research into technologies such as sensor networks, machine-to-machine (M2M), and machine-type communication (MTC) to connect objects. In the IoT environment, intelligent Internet of Things (IT) services can be provided, collecting and analyzing data generated from connected objects to create new value in human life. Through the integration and hybridization of existing information technology (IT) with various industries, IoT can be applied to areas such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart appliances, and advanced medical services.

[0007] Therefore, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine-to-machine (M2M), and machine-type communication (MTC) are implemented using techniques such as beamforming, MIMO, and array antennas. The application of cloud RAN as a big data processing technology is an example of the convergence of 5G and IoT technologies. Typically, mobile communication systems are developed to provide voice services while ensuring user activity.

[0008] However, mobile communication systems are not only expanding their voice services but also their data services, and have now evolved to the point of providing high-speed data services. However, due to resource shortages and users' demands for high-speed services, more advanced mobile communication systems are needed within the current mobile communication systems providing services.

[0009] In recent years, with the surge in mobile services due to the proliferation of smart devices, it has become increasingly difficult to cope with the increased data usage for providing cellular communication services using only existing licensed spectrum or licensed bands.

[0010] In this context, methods are being discussed for using unlicensed spectrum or unlicensed frequency bands (e.g., the 2.4 GHz band, the 5 GHz band, or higher frequency bands) to provide cellular communication services in order to address the lack of spectrum.

[0011] Unlike licensed frequency bands, where telecommunications operators secure exclusive usage rights through auctions and other procedures, unlicensed frequency bands allow multiple communication devices to be used simultaneously without restriction, provided they comply with certain levels of adjacent frequency band protection regulations. Therefore, when unlicensed frequency bands are used for cellular communication services, it is difficult to guarantee the communication quality at the level provided in licensed frequency bands, and interference with existing wireless communication equipment (e.g., wireless LAN devices) using unlicensed frequency bands is highly likely.

[0012] To utilize LTE and NR technologies in unlicensed frequency bands, prior research will be conducted on coexistence with existing equipment used in unlicensed frequency bands and efficient sharing of wireless channels with other wireless communication devices. Specifically, robust coexistence mechanisms (RCMs) need to be developed to ensure that devices using LTE and NR technologies in unlicensed frequency bands do not affect existing equipment used in unlicensed frequency bands. Summary of the Invention

[0013] Technical issues

[0014] The purpose of this specification is to provide a method for performing uplink / downlink transmissions in a wireless communication system based on the sharing of channel occupancy initiated by a user equipment.

[0015] Technical solution

[0016] This specification provides a method for receiving downlink transmissions in a wireless communication system.

[0017] In detail, a method performed by a user equipment includes: performing uplink transmission to a base station related to channel occupancy shared between the base station and the user equipment; and receiving downlink transmission from the base station after a gap from the time of receiving the uplink transmission, wherein the downlink transmission is performed based on channel access performed by the base station, channel access is performed based on the gap, and information included in the downlink transmission and resources on which the downlink transmission is performed are determined based on whether the user equipment has received a configuration of an energy detection threshold for channel occupancy from the base station.

[0018] The gap is less than 16μs, or it is 16μs or 25μs.

[0019] When the gap is less than 16 μs, the channel access is a channel access that allows downlink transmission without performing channel sensing. When the gap is 16 μs, the gap includes a sensing time slot within the last 9 μs, and the channel access is a channel access that allows downlink transmission when the sensing time slot is idle. When the gap is 25 μs, the gap is configured with a first interval of 16 μs including a first sensing time slot of 9 μs and a second interval of 9 μs as a second sensing time slot, and the channel access is a channel access that allows downlink transmission when the first and second sensing time slots are idle.

[0020] When a user equipment receives a configuration for an energy detection threshold for channel occupancy from a base station, the information included in the downlink transmission includes at least one of unicast or non-unicast transmission for the user equipment.

[0021] When the user equipment does not receive the configuration for the energy detection threshold for channel occupancy from the base station, the information included in the downlink transmission excludes unicast transmission, and the maximum number of symbols for the resources used to perform downlink transmission within the channel occupancy interval is any one of 2, 4, and 8.

[0022] When the subcarrier spacing (SCS) is 15 kHz, the resources for downlink transmission within the channel occupancy interval include a maximum of two symbols; when the SCS is 30 kHz, the resources for downlink transmission within the channel occupancy interval include a maximum of four symbols; and when the SCS is 60 kHz, the resources for downlink transmission within the channel occupancy interval include a maximum of eight symbols.

[0023] Uplink transmission is performed on configuration permission (CG) - physical uplink shared channel (PUSCH) resources that are semi-statically pre-configured from the base station.

[0024] The method further includes, when the user equipment receives configuration of an energy detection threshold for channel occupancy from the base station, receiving configuration of information about a table from the base station, the table including a value set for each of one or more parameters for channel occupancy and one or more indices corresponding to the set value, wherein the CG-PUSCH includes CG-Uplink Control Information (UCI), the CG-UCI including information indicating a first index among the one or more indices, and performing downlink transmission based on the value set for each of the one or more parameters corresponding to the first index.

[0025] One or more parameters include at least one of Channel Access Priority (CAPC), duration, or offset, wherein CAPC is the CAPC used in channel occupancy, duration is the number of time slots in which downlink transmission is performed, and offset is the difference between the end of the time slot in which the base station detects CG-UCI and the time slot in which downlink transmission begins.

[0026] The method further includes receiving, when the user equipment does not receive from the base station the configuration of an energy detection threshold for channel occupancy, an offset from the base station for indicating resources available for downlink transmission, wherein the CG-PUSCH includes a CG-UCI that includes information indicating that channel occupancy is possible, and performing downlink transmission on the last resource of the time slot in which the base station detects the CG-UCI and resources spaced apart and offset therefrom.

[0027] The maximum number of symbols for resources that include information in downlink transmission excluding unicast transmission and perform downlink transmission within the channel occupancy interval is any one of 2, 4, and 8.

[0028] When the subcarrier spacing (SCS) is 15 kHz, the resources for downlink transmission within the channel occupancy interval include a maximum of two symbols; when the SCS is 30 kHz, the resources for downlink transmission within the channel occupancy interval include a maximum of four symbols; and when the SCS is 60 kHz, the resources for downlink transmission within the channel occupancy interval include a maximum of eight symbols.

[0029] Furthermore, this specification provides a method for performing uplink transmissions in a wireless communication system, the method being performed by a user equipment, comprising: performing a first transmission as a configuration license (CG) uplink transmission to a base station on a first resource, wherein the CG uplink transmission is a transmission performed on resources semi-statically pre-configured from the base station; and performing a second transmission as a scheduled uplink transmission to the base station on a second resource, wherein the first resource and the second resource are sequential to each other in the time domain, the second transmission is performed on the second resource immediately following the last symbol of the first resource when at least one pre-configuration condition is satisfied, and the first transmission is discarded at the last symbol of the first resource when at least one pre-configuration condition is not satisfied.

[0030] At least one of the pre-configured conditions is based on channel access in which a variable-sized contention window (CW) is used to perform random backoff to perform the first transmission.

[0031] One of the pre-configuration conditions is that the resources allocated for the second transmission occupy all resource blocks (RBs) in the same frequency domain as the resources allocated for the first transmission.

[0032] One of the pre-configuration conditions is that when the bandwidth portion (BWP) of the resource allocated for the first transmission in the frequency domain is configured with multiple listen-before-talk (LBT) bandwidth subsets, the resource occupancy allocated for the second transmission includes all resource blocks (RBs) in at least one of the multiple LBT bandwidth subsets.

[0033] One of the pre-configuration conditions is a condition for performing the second transmission based on a second CAPC value that is less than or equal to the first channel access priority level (CAPC) value used in channel access.

[0034] One of the pre-configuration conditions is that the sum of the time domain of the first resource and the time domain of the second resource does not exceed the maximum channel occupancy time (MCOT) corresponding to the first CAPC value.

[0035] Furthermore, in this specification, a user equipment for receiving downlink transmissions in a wireless communication system includes: a communication module; and a processor that controls the communication module, wherein the processor performs uplink transmissions to a base station, the uplink transmissions being related to channel occupancy shared between the base station and the user equipment, and receives downlink transmissions performed by the base station after a gap from the time the uplink transmissions are received, wherein the downlink transmissions are performed based on channel access performed by the base station, channel access is performed based on the gap, and information included in the downlink transmissions and resources on which the downlink transmissions are performed are determined based on whether the user equipment receives a configuration of an energy detection threshold for channel occupancy from the base station.

[0036] When a user equipment receives a configuration for an energy detection threshold for channel occupancy from a base station, the information included in the downlink transmission includes at least one of unicast or non-unicast transmission for the user equipment. When the user equipment does not receive a configuration for an energy detection threshold for channel occupancy from a base station, the information included in the downlink transmission excludes unicast transmission, and the maximum number of symbols for resources used to perform downlink transmission within the channel occupancy interval is any one of 2, 4, and 8.

[0037] Beneficial effects

[0038] This specification provides a method for performing a gap-based channel access procedure for downlink transmission in a wireless communication system when a channel occupancy initiated by a user equipment is shared, thereby enabling efficient downlink transmission.

[0039] This specification provides a method for performing uplink transmission in a wireless communication system when a channel occupancy initiated by a user equipment is shared, thus enabling efficient uplink transmission. Attached Figure Description

[0040] Figure 1 This diagram illustrates an example of a wireless frame structure used in a wireless communication system.

[0041] Figure 2 This diagram illustrates an example of a downlink (DL) / uplink (UL) timeslot structure in a wireless communication system.

[0042] Figure 3 This is a diagram used to illustrate the physical channels used in 3GPP systems and typical signal transmission methods using those physical channels.

[0043] Figure 4 The diagram illustrates the SS / PBCH block used for initial cell access in a 3GPP NR system.

[0044] Figure 5 The diagram illustrates a procedure for transmitting control information and control channels in a 3GPP NR system.

[0045] Figure 6 The diagram shows a control resource set (CORESET) in a 3GPP NR system that can transmit the Physical Downlink Control Channel (PDCCH).

[0046] Figure 7 The diagram illustrates a method for configuring the PDCCH search space in a 3GPP NR system.

[0047] Figure 8 This is a conceptual diagram illustrating carrier aggregation.

[0048] Figure 9 This is a diagram used to illustrate single-carrier communication and multi-carrier communication.

[0049] Figure 10 This is a diagram illustrating an example of the application of cross-carrier scheduling technology.

[0050] Figure 11 This is a diagram illustrating the positions of OFDM symbols occupied by SSBs within multiple time slots of the licensed frequency band of the NR system according to an embodiment of the present invention.

[0051] Figure 12 This is a diagram illustrating the position of the time slot occupied by the SSB within a 5ms half-radio frame of the licensed frequency band of the NR system according to an embodiment of the present invention.

[0052] Figure 13 This is a diagram illustrating the position of OFDM symbols occupied by SSBs within a time slot comprising 16 OFDM symbols according to an embodiment of the present invention.

[0053] Figure 14 This is a block diagram illustrating the configuration of user equipment and base station according to an embodiment of the present invention.

[0054] Figure 15 This is a diagram illustrating the downlink channel access process according to an embodiment of the present invention.

[0055] Figure 16 This is a diagram illustrating the scheduling of uplink transmission according to an embodiment of the present invention.

[0056] Figure 17 This is a flowchart illustrating a method for a user equipment to receive downlink transmissions according to an embodiment of the present invention.

[0057] Figure 18 This is a flowchart illustrating a method for a user equipment to perform uplink transmission according to an embodiment of the present invention. Detailed Implementation

[0058] The terminology used in this specification adopts, as far as possible, commonly used terms that are widely used in light of the functions of this invention; however, these terms may be modified according to the intent, practice, and emergence of new technologies of those skilled in the art. Furthermore, in certain cases, there are terms arbitrarily chosen by the applicant, and in such cases, their meaning will be described in the corresponding descriptive section of this invention. Therefore, it is intended to reveal that the terminology used in this specification should not be analyzed solely based on its name, but rather on its substantive meaning within the entire specification.

[0059] Throughout the specification and subsequent claims, when an element is described as being “connected” to another element, that element may be “directly connected” to the other element or “electrically connected” to the other element via a third element. Furthermore, unless explicitly stated otherwise, the word “comprising” will be understood to imply the inclusion of the stated element without implying the exclusion of any other elements. Additionally, in some exemplary embodiments, limitations such as “greater than or equal to” or “less than or equal to” based on a specific threshold may be appropriately replaced with “greater than” or “less than”, respectively.

[0060] 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), and Single Carrier-FDMA (SC-FDMA). CDMA can be implemented using wireless technologies such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented using wireless technologies such as Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), and Enhanced Data Rate GSM Evolution (EDGE). OFDMA can be implemented using wireless technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and Evolved UTRA (E-UTRA). UTRA is part of the Universal Mobile Telecommunications System (UMTS). The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is part of Evolved UMTS (E-UMTS) using Evolved UMTS Terrestrial Radio Access (E-UTRA), and LTE Advanced (A) is an evolved version of 3GPP LTE. 3GPP New Radio (NR) is a system designed separately from LTE / LTE-A and is intended to support Enhanced Mobile Broadband (eMBB), Ultra-Reliable Low Latency Communication (URLLC), and Massive Machine-Type Communication (mMTC) services as required by IMT-2020. For clarity, 3GPP NR is described primarily, but the technical concept of this invention is not limited thereto.

[0061] Unless otherwise stated herein, a base station may include a next-generation node B (gNB) as defined in 3GPP NR. Furthermore, unless otherwise stated, a terminal may include a user equipment (UE). In the following description, each embodiment is described separately to aid understanding; however, each embodiment may be used in combination with each other. In this specification, the configuration of the UE may be indicated by the configuration of the base station. More specifically, the base station may configure the values ​​of parameters used in the operation of the UE or the wireless communication system by transmitting channels or signals to the UE.

[0062] Figure 1This diagram illustrates an example of a wireless frame structure used in a wireless communication system.

[0063] refer to Figure 1 The radio frames (or radio frames) used in 3GPP NR systems can have a duration of 10ms (Δf). max N f / 100)*T c The length of the radio frame is Δf. Furthermore, a radio frame consists of 10 equal-sized subframes (SF). Here, Δf... max =480*10 3 Hz, N f =4096, T c =1 / (Δf) ref *N f,ref ), Δf ref =15*10 3 Hz, and N f,ref =2048. Numbers from 0 to 9 can be assigned to 10 subframes within a single radio frame. Each subframe is 1ms long and can include one or more time slots depending on the subcarrier spacing. More specifically, in 3GPP NR systems, the usable subcarrier spacing is 15*2. μ The subcarrier spacing can be configured as μ = 0, 1, 2, 3, or 4. That is, 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz can be used for subcarrier spacing. A subframe of 1 ms length can include 2... μ There are 2 time slots. In this case, the length of each time slot is 2. -μ ms. This can range from 0 to 2. μ The number -1 is assigned to 2 within a subframe. μ Each time slot. Furthermore, slots from 0 to 10*2 can be allocated. μ The number -1 is assigned to a time slot within a radio frame. Time resources can be distinguished by at least one of the radio frame number (also known as the radio frame index), subframe number (also known as the subframe index), and time slot number (or time slot index).

[0064] Figure 2 This diagram illustrates an example of a downlink (DL) / uplink (UL) timeslot structure in a wireless communication system. Specifically, Figure 2 The structure of the resource grid of the 3GPP NR system is shown.

[0065] Each online port has a resource grid. (See reference) Figure 2A time slot comprises multiple Orthogonal Frequency Division Multiplexing (OFDM) symbols in the time domain and multiple Resource Blocks (RBs) in the frequency domain. An OFDM symbol also refers to a symbol interval. Unless otherwise specified, an OFDM symbol may be simply referred to as a symbol. An RB comprises 12 consecutive subcarriers in the frequency domain. (See reference...) Figure 2 The signal transmitted from each time slot can be composed of N size,μ grid,x *N RB sc Subcarriers and N slot symb The resource grid of OFDM symbols is used for representation. Here, x = DL when the signal is a DL signal, and x = UL when the signal is a UL signal. N size,μ grid,x This represents the number of resource blocks (RBs) based on the subcarrier spacing component μ (x is DL or UL), and N slot symb Indicates the number of OFDM symbols in the time slot. N RB sc It is the number of subcarriers that make up an RB and N RB sc =12. OFDM symbols can be referred to as cyclic shift OFDM (CP-OFDM) symbols or discrete Fourier transform extended OFDM (DFT-s-OFDM) symbols according to the multiple access scheme.

[0066] The number of OFDM symbols included in a time slot can vary depending on the length of the cyclic prefix (CP). For example, with normal CP, a time slot includes 14 OFDM symbols, but with extended CP, a time slot can include 12 OFDM symbols. In certain embodiments, extended CP can only be used with a 60 kHz subcarrier spacing. Figure 2 For ease of description, as an example, a time slot is configured with 14 OFDM symbols; however, embodiments of this disclosure can be applied in a similar manner to time slots with different numbers of OFDM symbols. References Figure 2 Each OFDM symbol includes N in the frequency domain. size,μ grid,x *N RB sc Subcarriers can be categorized into data subcarriers for data transmission, reference signal subcarriers for reference signal transmission, and guard bands. The carrier frequency is also known as the center frequency (fc).

[0067] An RB can be composed of N in the frequency domain RB sc(For example, 12) consecutive subcarriers are defined. For reference, a resource configured with one OFDM symbol and one subcarrier can be called a resource element (RE) or tone. Therefore, an RB can be configured with N slot symb *N RB sc Each resource element in the resource grid can be uniquely defined by a pair of indices (k, l) in a time slot. k can be from 0 to N in the frequency domain. size,μ grid,x *N RB sc -1 is the index assigned, and l can be from 0 to N in the time domain. slot symb -1 The index assigned.

[0068] To enable the UE to receive or transmit signals from the base station, the UE's time / frequency can be synchronized with the base station's time / frequency. This is because when the base station and the UE are synchronized, the UE can determine the necessary time and frequency parameters to demodulate the DL signal and transmit the UL signal at the correct time.

[0069] Each symbol of a radio frame used in Time Division Duplex (TDD) or unpaired spectrum can be configured with at least one of DL symbol, UL symbol, and flexible symbol. Radio frames used as DL carriers in Frequency Division Duplex (FDD) or paired spectrum can be configured with either DL symbol or flexible symbol, while radio frames used as UL carriers can be configured with either UL symbol or flexible symbol. In DL symbols, DL transmission is possible, but UL transmission is not. In UL symbols, UL transmission is possible, but DL transmission is not. A flexible symbol can be determined as being used as either DL or UL based on the signal.

[0070] Information regarding the type of each symbol—that is, information indicating any one of DL symbols, UL symbols, and flexible symbols—can be configured using cell-specific or public Radio Resource Control (RRC) signals. Furthermore, information regarding the type of each symbol can be additionally configured using UE-specific or dedicated RRC signals. The base station uses cell-specific RRC signals to inform i) the period of the cell-specific time slot configuration, ii) the number of time slots containing only DL symbols from the beginning of the cell-specific time slot configuration period, iii) the number of DL symbols starting from the first symbol of the time slot immediately following a time slot containing only DL symbols, iv) the number of time slots containing only UL symbols from the end of the cell-specific time slot configuration period, and v) the number of UL symbols starting from the last symbol of the time slot immediately preceding a time slot containing only UL symbols. Here, a symbol not configured with either UL or DL ​​symbols is a flexible symbol.

[0071] When the information about the symbol type is configured by UE-specific RRC signaling, the base station can signal whether the flexible symbol is a DL symbol or a UL symbol by using cell-specific RRC signaling. In this case, the UE-specific RRC signaling cannot change the DL symbol or UL symbol configured by the cell-specific RRC signaling into another symbol type. The UE-specific RRC signaling can signal the number of DL symbols among the N symbols of the corresponding time slot for each time slot and the number of UL symbols among the N symbols of the corresponding time slot. slot symb The number of DL symbols among the N symbols of the corresponding time slot and the number of UL symbols among the N symbols of the corresponding time slot. slot symb In this case, the DL symbols of the time slot can be continuously configured from the first symbol to the i-th symbol of the time slot. In addition, the UL symbols of the time slot can be continuously configured from the j-th symbol to the last symbol of the time slot (where i < j). In a time slot, the symbol that is not configured with either a UL symbol or a DL symbol is a flexible symbol.

[0072] The type of symbol configured by the above RRC signaling can be referred to as a semi-static DL / UL configuration. In the previously configured semi-static DL / UL configuration by RRC signaling, the flexible symbol can be indicated as a DL symbol, a UL symbol, or a flexible symbol by the dynamic time slot format information (SFI) sent on the physical DL control channel (PDCCH). In this case, the DL symbol or UL symbol configured by the RRC signaling will not be changed into another symbol type. Table 1 illustrates the dynamic SFI that the base station can indicate to the UE.

[0073] [Table 1]

[0074]

[0075] In Table 1, D represents a DL symbol, U represents a UL symbol, and X represents a flexible symbol. As shown in Table 1, up to two DL / UL switches in one time slot can be allowed.

[0076] Figure 3 It is a diagram for explaining the physical channels used in a 3GPP system (e.g., NR) and a typical signal transmission method using the physical channel.

[0077] If the power of the UE is turned on or the UE camps on a new cell, the UE performs an initial cell search (step S101). Specifically, the UE can synchronize with the BS during the initial cell search. To this end, the UE can receive the primary synchronization signal (PSS) and the secondary synchronization signal (SSS) from the base station to synchronize with the base station and obtain information such as the cell ID. Thereafter, the UE can receive the physical broadcast channel from the base station and obtain the broadcast information in the cell.

[0078] After the initial cell search is completed, the UE receives the Physical Downlink Shared Channel (PDSCH) based on the Physical Downlink Control Channel (PDCCH) and the information in the PDCCH, enabling the UE to obtain more specific system information than the system information obtained through the initial cell search (S102). Here, the system information received by the UE is the cell common system information used by the UE to operate normally in the physical layer of Radio Resource Control (RRC), and is referred to as the remaining system information, or System Information Block (SIB) 1.

[0079] When a UE initially accesses a base station or lacks radio resources for signal transmission (i.e., the UE is in RRC_idle mode), the UE can perform a random access procedure to the base station (steps S103 to S106). First, the UE can send a preamble via the Physical Random Access Channel (PRACH) (step S103) and receive a response message for the preamble from the base station via the PDCCH and the corresponding PDSCH (step S104). When the UE receives a valid random access response message, the UE sends data including the UE's identifier to the base station via the Physical Uplink Shared Channel (PUSCH) indicated by the UL grant sent from the base station via the PDCCH (step S105). Next, the UE waits for the reception of the PDCCH as an indication from the base station for conflict resolution. If the UE successfully receives the PDCCH via the UE's identifier (step S106), the random access procedure is terminated. During the random access procedure, the UE can obtain UE-specific system information for normal operation of the UE in the physical layer of the RRC layer. When the UE obtains the UE-specific system information, the UE enters the RRC connection mode (RRC_connection mode).

[0080] The RRC layer is used to generate or manage messages that control the connection between the UE and the Radio Access Network (RAN). More specifically, within the RRC layer, the base station and UE can perform tasks such as broadcasting cell system information required by each UE in the cell, managing mobility and handover, UE measurement reports, and storage management including UE capability management and device management. Typically, because the update cycle of signals transmitted in the RRC layer is longer than the Transmission Time Interval (TTI) in the physical layer, RRC signals remain unchanged and are maintained for considerable intervals.

[0081] Following the above procedure, the UE receives the PDCCH / PDSCH (step S107) and transmits the Physical Uplink Shared Channel (PUSCH) / Physical Uplink Control Channel (PUCCH) (step S108) as a general UL / DL signal transmission procedure. Specifically, the UE can receive downlink control information (DCI) via the PDCCH. The DCI may include control information for the UE, such as resource allocation information. Furthermore, the format of the DCI can vary depending on the intended purpose. The uplink control information (UCI) transmitted by the UE to the base station via the UL includes DL / UL ACK / NACK signals, Channel Quality Indicator (CQI), Precoding Matrix Index (PMI), Rank Indicator (RI), etc. Here, CQI, PMI, and RI can be included in the Channel State Information (CSI). In a 3G PPNR system, the UE can transmit control information such as the aforementioned HARQ-ACK and CSI via the PUSCH and / or PUCCH.

[0082] Figure 4 The diagram illustrates the SS / PBCH block used for initial cell access in a 3GPP NR system.

[0083] When power is on or when the UE wants to connect to a new cell, it can obtain time and frequency synchronization with that cell and perform an initial cell search procedure. The UE can detect the physical cell identifier N of the cell during the cell search procedure. cell ID Therefore, the UE can receive synchronization signals from the base station, such as the primary synchronization signal (PSS) and secondary synchronization signal (SSS), and synchronize with the base station. In this case, the UE can obtain information such as the cell identifier (ID).

[0084] refer to Figure 4 Section (a) will describe the synchronization signal (SS) in more detail. Synchronization signals can be classified into PSS and SSS. PSS can be used to obtain time-domain synchronization and / or frequency-domain synchronization, such as OFDM symbol synchronization and slot synchronization. SSS can be used to obtain frame synchronization and cell group ID. (See reference...) Figure 4According to (a) and Table 2, the SS / PBCH block can be configured with 20 consecutive RBs (=240 subcarriers) on the frequency axis and 4 consecutive OFDM symbols on the time axis. In this case, in the SS / PBCH block, the PSS is transmitted in the first OFDM symbol via subcarriers 56 to 182 and the SSS is transmitted in the third OFDM symbol. Here, the lowest subcarrier index of the SS / PBCH block is numbered starting from 0. In the first OFDM symbol for transmitting the PSS, the base station does not transmit signals via the remaining subcarriers, i.e., subcarriers 0 to 55 and subcarriers 183 to 239. Furthermore, in the third OFDM symbol for transmitting the SSS, the base station does not transmit signals via subcarriers 48 to 55 and subcarriers 183 to 191. The base station transmits the Physical Broadcast Channel (PBCH) via the remaining REs in the SS / PBCH block, excluding the signals mentioned above.

[0085] [Table 2]

[0086]

[0087] The SS allows a total of 1008 unique physical layer cell IDs to be divided into 336 physical layer cell identifier groups through a combination of three PSSs and SSSs. Each group includes three unique identifiers, specifically ensuring that each physical layer cell ID is only a part of one physical layer cell identifier group. Therefore, the physical layer cell ID N cell ID =3N (1) ID +N (2) ID An index N, ranging from 0 to 335, can be used to indicate the physical layer cell identifier group. (1) ID and an index N indicating the range of physical layer identifiers in the physical layer cell identifier group from 0 to 2. (2) ID Uniquely defined. The UE can detect the PSS and identify one of three unique physical layer identifiers. Furthermore, the UE can detect the SSS and identify one of 336 physical layer cell IDs associated with the physical layer identifier. In this case, the sequence d of the PSS... PSS (n) is as follows.

[0088] d PSS (n) = 1 - 2x(m)

[0089]

[0090] 0 ≤ n < 127

[0091] Here, x(i+7) = (x(i+4) + x(i)) mod 2 and is given as

[0092] [x(6) x(5) x(4) x(3) x(2) x(1) x(0)]=[1 1 1 0 1 1 0].

[0093] In addition, the sequence d of SSS SSS (n) is as follows.

[0094] d sss (n)=[1-2x0((n+m0)mod127)][1-2x1((n+m1)mod127)]

[0095]

[0096]

[0097] 0 ≤ n < 127

[0098] here,

[0099] And was given as

[0100] [x0(6) x0(5) x0(4) x0(3) x0(2) x0(1) x0(0)]=[0 0 0 0 0 0 1]

[0101] [x1(6) x1(5) x1(4) x1(3) x1(2) x1(1) x1(0)]=[0 0 0 0 0 0 1].

[0102] A radio frame with a length of 10ms can be divided into two half-frames with a length of 5ms each. (Reference) Figure 4Section (b) describes the time slots for transmitting the SS / PBCH block in each half-frame. The time slot for transmitting the SS / PBCH block can be any of cases A, B, C, D, and E. In case A, the subcarrier spacing is 15 kHz and the start time of the SS / PBCH block is the ({2, 8} + 14*n)th symbol. In this case, at carrier frequencies of 3 GHz or lower, n = 0 or 1. Furthermore, at carrier frequencies above 3 GHz and below 6 GHz, n can be 0, 1, 2, or 3. In case B, the subcarrier spacing is 30 kHz and the start time of the SS / PBCH block is {4, 8, 16, 20} + 28*n. In this case, at carrier frequencies of 3 GHz or lower, n = 0. Furthermore, at carrier frequencies above 3 GHz and below 6 GHz, n can be 0 or 1. In case C, the subcarrier spacing is 30 kHz and the start time of the SS / PBCH block is the ({2, 8} + 14*n)th symbol. In this case, at carrier frequencies of 3 GHz or lower, n = 0 or 1. Furthermore, at carrier frequencies above 3 GHz but below 6 GHz, n can be 0, 1, 2, or 3. In case D, the subcarrier spacing is 120 kHz and the start time of the SS / PBCH block is the ({4, 8, 16, 20} + 28*n)th symbol. In this case, at carrier frequencies of 6 GHz or higher, n = 0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18. In case E, the subcarrier spacing is 240 kHz and the start time of the SS / PBCH block is the ({8, 12, 16, 20, 32, 36, 40, 44} + 56*n)th symbol. In this case, at carrier frequencies of 6 GHz or higher, n = 0, 1, 2, 3, 5, 6, 7, 8.

[0103] Figure 5 The diagram illustrates the process of transmitting control information and using the control channel in a 3GPP NR system. (Reference) Figure 5(a) The base station may add a Cyclic Redundancy Check (CRC) masked with a Radio Network Temporary Identifier (RNTI) (e.g., XOR operation) to the control information (e.g., downlink control information (DCI)) (step S202). The base station may scramble the CRC with an RNTI value determined according to the purpose / objective of each control information. The common RNTI used by one or more UEs may include at least one of System Information RNTI (SI-RNTI), Paging RNTI (P-RNTI), Random Access RNTI (RA-RNTI), and Transmit Power Control RNTI (TPC-RNTI). In addition, UE-specific RNTIs may include at least one of Cell Temporary RNTI (C-RNTI) and CS-RNTI. Thereafter, the base station may perform rate matching according to the amount of resources used for PDCCH transmission after performing channel coding (e.g., polarity coding) (step S204) (step S206). Thereafter, the base station may multiplex the DCI based on the PDCCH structure based on Control Channel Elements (CCE) (step S208). Furthermore, the base station can apply additional processes such as scrambling, modulation (e.g., QPSK), interleaving, etc., to the multiplexed DCI (step S210), and then map the DCI to the resources to be transmitted. A CCE is the basic resource unit used for a PDCCH, and a CCE can include multiple (e.g., six) Resource Element Groups (REGs). A REG can be configured with multiple (e.g., 12) REs. The number of CCEs used for a PDCCH can be defined as the aggregation level. In 3GPP NR systems, aggregation levels of 1, 2, 4, 8, or 16 can be used. Figure 5 (b) is a diagram relating to CCE aggregation levels and PDCCH multiplexing, and illustrates the type of CCE aggregation level for a PDCCH and the CCEs sent in the control area accordingly.

[0104] Figure 6 The diagram shows a control resource set (CORESET) in a 3GPP NR system that can transmit the Physical Downlink Control Channel (PUCCH).

[0105] A CORESET is a time-frequency resource in which PDCCH (i.e., control signals for the UE) is transmitted. Furthermore, a search space, described later, can be mapped to a CORESET. Therefore, the UE can monitor the time-frequency domain designated as a CORESET instead of all frequency bands used for PDCCH reception, and decode the PDCCH mapped to the CORESET. The base station can configure one or more CORESETs for each cell for the UE. A CORESET can be configured with up to three consecutive symbols on the time axis. Additionally, a CORESET can be configured in units of six consecutive PRBs on the frequency axis. Figure 5 In this embodiment, CORESET#1 is configured with consecutive PRBs, while CORESET#2 and CORESET#3 are configured with discontinuous PRBs. A CORESET can reside in any symbol within a time slot. For example, in... Figure 5 In one embodiment, CORESET#1 begins at the first symbol of the time slot, CORESET#2 begins at the fifth symbol of the time slot, and CORESET#9 begins at the ninth symbol of the time slot.

[0106] Figure 7 The diagram illustrates a method for setting up the PUCCH search space in a 3GPP NR system.

[0107] To transmit PDCCH to a UE, each CORESET may have at least one search space. In embodiments of this disclosure, the search space is the set of all time-frequency resources (hereinafter referred to as PDCCH candidates) capable of being used to transmit a UE's PDCCH. The search space may include a common search space that requires UEs of 3GPP NR to search together and a terminal-specific search space or UE-specific search space that requires a specific UE to search. In the common search space, a UE may monitor a PDCCH that is configured to be searched together by all UEs belonging to the same base station cell. Furthermore, a UE-specific search space may be set for each UE, such that the UE monitors the PDCCH allocated to each UE at search space locations that differ depending on the UE. In the case of a UE-specific search space, the search spaces between UEs may partially overlap and be allocated due to the limited control area that can be allocated PDCCH. Monitoring the PDCCH includes blind decoding of PDCCH candidates in the search space. When blind decoding is successful, it can be expressed as (successfully) detecting / receiving the PDCCH, and when blind decoding fails, it can be expressed as not detecting / receiving or not successfully detecting / receiving the PDCCH.

[0108] For ease of explanation, a PDCCH scrambled with a Group Common (GC) RNTI previously known to one or more UEs to transmit DL control information to one or more UEs is called a Group Common (GC) PDCCH or a common PDCCH. Furthermore, a PDCCH scrambled with a RNTI of a specific terminal already known to a specific UE to transmit UL scheduling information or DL ​​scheduling information to that specific UE is called a UE-specific PDCCH. Common PDCCHs can be included in the common search space, and UE-specific PDCCHs can be included in either the common search space or the UE-specific PDCCH.

[0109] The base station can signal to each UE or group of UEs via the PDSCH information regarding resource allocation for the Paging Channel (PCH) and Downlink Shared Channel (DL-SCH) as transport channels (i.e., DL clearance) or resource allocation for the Uplink Shared Channel (UL-SCH) and Hybrid Automatic Repeat Request (HARQ) (i.e., UL clearance). The base station can transmit PCH transport blocks and DL-SCH transport blocks via the PDSCH. The base station can also transmit data excluding specific control information or specific service data via the PDSCH. Furthermore, the UE can receive data excluding specific control information or specific service data via the PDSCH.

[0110] The base station can include information in the PDCCH about which UE (one or more UEs) the PDSCH data is sent to and how the PDSCH data will be received and decoded by the corresponding UE, and then send the PDCCH. For example, suppose the DCI sent on a particular PDCCH is CRC masked with RNTI "A", and the DCI indicates that the PDSCH is allocated to radio resource "B" (e.g., frequency location) and indicates transmission format information "C" (e.g., transport block size, modulation scheme, coding information, etc.). The UE uses the RNTI information it possesses to monitor the PDCCH. In this case, if there is a UE performing blind decoding of the PDCCH using RNTI "A", then that UE receives the PDCCH and, based on the information in the received PDCCH, receives the PDSCH indicated by "B" and "C".

[0111] Table 3 shows an example of the Physical Uplink Control Channel (PUCCH) used in a wireless communication system.

[0112] [Table 3]

[0113] PUCCH format Length of OFDM symbol Number of bits 0 1-2 ≤2 1 4-14 ≤2 2 1-2 ＞2 3 4-14 ＞2 4 4-14 ＞2

[0114] PUCCH can be used to send the following UL control information (UCI).

[0115] - Scheduling Request (SR): Information used to request UL UL-SCH resources.

[0116] -HARQ-ACK: A response to the PDCCH (indicating DL SPS release) and / or to a DL transport block (TB) on the PDSCH. HARQ-ACK indicates whether information successfully transmitted on the PDCCH or PDSCH has been received. HARQ-ACK responses include positive ACK (abbreviated as ACK), negative ACK (hereinafter NACK), discontinuous transmission (DTX), or NACK / DTX. Here, the terms HARQ-ACK are used interchangeably with HARQ-ACK / NACK and ACK / NACK. Typically, ACK can be represented by a bit value of 1, while NACK can be represented by a bit value of 0.

[0117] - Channel State Information (CSI): Feedback information about the DL channel. The UE generates it based on the CSI-reference signal (RS) transmitted by the base station. MIMO-related feedback information includes the Rank Indicator (RI) and the Precoding Matrix Indicator (PMI). The CSI can be divided into CSI Part 1 and CSI Part 2 based on the information indicated by the CSI.

[0118] In the 3GPP NR system, five PUCCH formats can be used to support various service scenarios, channel environments, and frame structures.

[0119] PUCCH format 0 is a format capable of delivering 1 or 2 bits of HARQ-ACK information or SR. PUCCH format 0 can be transmitted using one or two OFDM symbols on the time axis and one PRB on the frequency axis. When transmitting PUCCH format 0 over two OFDM symbols, the same sequence on both symbols can be transmitted using different RBs. In this case, the sequence can be a cyclically shifted (CS) sequence from the underlying sequence used in PUCCH format 0. Thus, the UE can obtain frequency diversity gain. More specifically, the UE can, according to M... bit Bit UCI (M) bit =1 or 2) to determine the cyclic shift (CS) value m cs Additionally, this can be achieved by using a predetermined CS value m. cs The cyclic shift sequence is mapped to an OFDM symbol and 12 REs of an RB to transmit a base sequence of length 12. When the number of cyclic shifts available to the UE is 12 and M... bit When M = 1, 1-bit UCI 0 and 1 can be mapped to two cyclic shift sequences, with the cyclic shift values ​​of these two sequences differing by 6. Additionally, when M... bitWhen =2, the 2-bit UCI 00, 01, 11 and 10 can be mapped to four cyclic shift sequences with a difference of 3 in the cyclic shift value.

[0120] PUCCH format 1 can deliver 1 or 2 bits of HARQ-ACK information or SR. PUCCH format 1 can be transmitted using consecutive OFDM symbols on the time axis and one PRB on the frequency axis. Here, the number of OFDM symbols occupied by PUCCH format 1 can be one of 4 to 14. More specifically, it can be used for M... bit BPSK modulation is performed using a UCI of 1. The UE can then use Quadrature Phase Shift Keying (QPSK) to modulate the M... bit Modulation is performed using a UCI of 2. The signal is obtained by multiplying the modulated complex-valued symbol d(0) by a sequence of length 12. In this case, the sequence can be the base sequence used for PUCCH format 0. The UE transmits the obtained signal by extending the even-numbered OFDM symbols assigned to PUCCH format 1 with a time-axis orthogonal cover code (OCC). PUCCH format 1 determines the maximum number of different UEs multiplexed in an RB based on the length of the OCC to be used. The demodulation reference signal (DMRS) can be extended with the OCC and mapped to the odd-numbered OFDM symbols of PUCCH format 1.

[0121] PUCCH format 2 can deliver more than 2 bits of UCI. PUCCH format 2 can be transmitted via one or two OFDM symbols on the time axis and one or more RBs on the frequency axis. When transmitting PUCCH format 2 in two OFDM symbols, the sequences transmitted in different RBs through the two OFDM symbols can be identical. Here, the sequence can be multiple modulated complex-valued symbols d(0), ..., d(M). symbol -1). Here, M symbol It can be M bit / 2. Through this, the UE can obtain frequency diversity gain. More specifically, for M... bit One bit UCI (M bit >2) Perform bit-level scrambling, QPSK modulation, and map it to one or two OFDM symbols' RBs. Here, the number of RBs can be one from 1 to 16.

[0122] PUCCH format 3 or PUCCH format 4 can deliver more than 2 bits of UCI. PUCCH format 3 or PUCCH format 4 can be transmitted via consecutive OFDM symbols on the time axis and one PRB on the frequency axis. The number of OFDM symbols occupied by PUCCH format 3 or PUCCH format 4 can be one of 4 to 14. Specifically, the UE utilizes π / 2-binary phase shift keying (BPSK) or QPSK to transmit M... bit One bit UCI (M bit >2) Modulate to generate complex numerical symbols d(0) to d(M) symb -1). Here, when using π / 2-BPSK, M symb =M bit However, when using QPSK, M symb =M bit / 2. The UE may not apply block unit extension to PUCCH format 3. However, the UE may use a 12-length PreDFT-OCC to apply block unit extension to one RB (i.e., 12 subcarriers), allowing PUCCH format 4 to have two or four multiplexing capabilities. The UE performs transmit precoding (or DFT precoding) on ​​the extended signal and maps it to each RE to transmit the extended signal.

[0123] In this scenario, the number of Restricted Blocks (RBs) occupied by PUCCH format 2, PUCCH format 3, or PUCCH format 4 can be determined based on the length of the UCI sent by the UE and the maximum coding rate. When the UE uses PUCCH format 2, it can send HARQ-ACK and CSI information together via PUCCH. When the number of RBs that the UE can send exceeds the maximum number of RBs that can be used with PUCCH format 2, PUCCH format 3, or PUCCH format 4, the UE can choose not to send some UCI information based on the priority of the UCI information, and instead only send the remaining UCI information.

[0124] PUCCH format 1, PUCCH format 3, or PUCCH format 4 can be configured using the RRC signal to indicate frequency hopping in the time slot. When frequency hopping is configured, the index of the RB to be hopped can be configured using the RRC signal. When PUCCH format 1, PUCCH format 3, or PUCCH format 4 is transmitted over N OFDM symbols on the time axis, the first transition can have floor (N / 2) OFDM symbols and the second transition can have ceiling (N / 2) OFDM symbols.

[0125] PUCCH format 1, PUCCH format 3, or PUCCH format 4 can be configured to be repeatedly transmitted in multiple time slots. In this case, the number K of time slots in which the PUCCH is repeatedly transmitted can be configured via an RRC signal. The repeatedly transmitted PUCCH must begin at a constant position in the OFDM symbol within each time slot and have a constant length. When one of the OFDM symbols in the time slot where the UE should transmit the PUCCH is indicated as a DL symbol via an RRC signal, the UE can choose not to transmit the PUCCH in the corresponding time slot and delay the transmission of the PUCCH to the next time slot.

[0126] In 3GPP NR systems, a UE can perform transmission / reception using a bandwidth equal to or less than the carrier (or cell) bandwidth. For this purpose, the UE can receive a bandwidth portion (BWP) of a continuous bandwidth configured with some bandwidth of the carrier bandwidth. A UE operating under TDD or in unpaired spectrum can receive up to four DL / UL BWP pairs on a single carrier (or cell). Additionally, a UE can activate one DL / UL BWP pair. A UE operating under FDD or in paired spectrum can receive up to four DL BWPs on a DL carrier (or cell) and up to four ULBWPs on a UL carrier (or cell). A UE can activate one DL BWP and one UL BWP for each carrier (or cell). The UE may not perform reception or transmission in time-frequency resources other than the activated BWP. The activated BWP can be referred to as the active BWP.

[0127] The base station can indicate the active BWP among those configured by the UE via downlink control information (DCI). The BWP indicated by the DCI is activated, and other configured BWPs are deactivated. In a TDD-operated carrier (or cell), the base station can include a bandwidth portion indicator (BPI) in the DCI used for scheduling PDSCH or PUSCH, which indicates the BWP to be activated to change the UE's DL / UL BWP pair. The UE can receive the DCI used for scheduling PDSCH or PUSCH and can identify the DL / UL BWP pair activated based on the BPI. For a DL carrier (or cell) operating in FDD, the base station can include a BPI in the DCI used for scheduling PDSCH indicating the BWP to be activated to change the UE's DL BWP. For a UL carrier (or cell) operating in FDD, the base station can include a BPI in the DCI used for scheduling PUSCH indicating the BWP to be activated to change the UE's UL BWP.

[0128] Figure 8 This is a conceptual diagram illustrating carrier aggregation.

[0129] Carrier aggregation is a method in which a UE uses multiple frequency blocks or (in a logical sense) cells configured with UL resources (or component carriers) and / or DL ​​resources (or component carriers) as a large logical band so that the wireless communication system can use a wider bandwidth. A component carrier can also be referred to by the terms primary cell (PCell), secondary cell (SCell), or primary SCell (PScell). However, for convenience, the term "component carrier" will be used below.

[0130] refer to Figure 8 As an example of a 3GPP NR system, the entire system bandwidth can include up to 16 component carriers, and each component carrier can have a bandwidth of up to 400 MHz. Component carriers can include one or more physically contiguous subcarriers. Although in Figure 8 The diagram shows each component carrier with the same bandwidth, but this is merely an example, and each component carrier can have a different bandwidth. Furthermore, although each component carrier is shown as adjacent to each other on the frequency axis, the diagram is shown conceptually, and each component carrier can be physically adjacent to each other or spaced apart.

[0131] Different center frequencies can be used for each component carrier. Alternatively, a common center frequency can be used for physically adjacent component carriers. Assuming in Figure 8 In one embodiment, all component carriers are physically adjacent, so center frequency A can be used in all component carriers. Alternatively, assuming that the component carriers are not physically adjacent to each other, then center frequency A and center frequency B can be used in each component carrier.

[0132] When extending the total system bandwidth through carrier aggregation, the bandwidth used for communication with each UE can be defined on a component carrier basis. UE A can use 100MHz as the total system bandwidth and perform communication using all five component carriers. UEs B1-B5 can perform communication using only 20MHz bandwidth and one component carrier. UEs C1 and C2 can each use 40MHz bandwidth and two component carriers for communication. These two component carriers can be logically / physically adjacent or non-adjacent. UE C1 represents the case of using two non-adjacent component carriers, while UE C2 represents the case of using two adjacent component carriers.

[0133] Figure 9 This is a diagram used to illustrate single-carrier communication and multi-carrier communication. Specifically, Figure 9 (a) shows the single-carrier subframe structure and Figure 9 (b) shows the multi-carrier subframe structure.

[0134] refer to Figure 9 In (a) of the FDD mode, a typical wireless communication system can perform data transmission or reception using a DL band and a corresponding UL band. In another specific embodiment, in TDD mode, the wireless communication system can divide radio frames into UL time units and DL time units in the time domain, and perform data transmission or reception using the UL / DL time units. (See reference...) Figure 9 (b) enables the aggregation of three 20MHz component carriers (CCs) into each of the UL and DL, thus supporting a bandwidth of 60MHz. Each CC can be adjacent to or not adjacent to each other in the frequency domain. Figure 9 (b) illustrates a case where the bandwidth of the UL CC and the DL CC are the same and symmetrical, but the bandwidth of each CC can be determined independently. Furthermore, asymmetric carrier aggregation with different numbers of UL CCs and DL CCs is possible. The DL / UL CCs allocated / configured to a specific UE via RRC can be referred to as the serving DL / UL CCs for that specific UE.

[0135] A base station can communicate with a UE by activating some or all of the UE's serving CCs or by deactivating some CCs. The base station can change the CCs to be activated / deactivated, and can change the number of CCs to be activated / deactivated. If the base station allocates CCs available to the UE as cell-specific or UE-specific, at least one of the allocated CCs will not be deactivated unless the CC allocation for the UE is completely reconfigured or the UE is handed over. A CC that is not deactivated by the UE is called the primary CC (PCC) or primary cell (PCell), while CCs that the base station can freely activate / deactivate are called secondary CCs (SCCs) or secondary cells (SCells).

[0136] Meanwhile, 3GPP NR uses the concept of cells to manage radio resources. A cell is defined as a combination of DL resources and UL resources, i.e., a combination of DL CC and UL CC. A cell can be configured with DL resources alone, or it can be configured with a combination of DL resources and UL resources. When carrier aggregation is supported, the link between the carrier frequencies of DL resources (or DL ​​CC) and UL resources (or UL CC) can be indicated by system information. The carrier frequency refers to the center frequency of each cell or CC. The cell corresponding to a PCC is called a PCell, and the cell corresponding to an SCC is called an SCell. The carrier corresponding to a PCell in DL is the DL PCC, and the carrier corresponding to a PCell in UL is the UL PCC. Similarly, the carrier corresponding to an SCell in DL is the DL SCC, and the carrier corresponding to an SCell in UL is the UL SCC. Depending on the UE's capabilities, a serving cell can be configured with one PCell and zero or more SCells. In the case of a UE in the RRC_CONNECTED state but not configured for carrier aggregation or not supporting carrier aggregation, only one serving cell is configured with only a PCell.

[0137] As mentioned above, the term "cell" used in carrier aggregation is distinguished from the term "cell" referring to a geographical area that provides communication services through a base station or an antenna array. That is, a component carrier can also be referred to as a scheduled cell, a scheduled cell, a primary cell (PCell), a secondary cell (SCell), or a primary SCell (PScell). However, to distinguish between cells representing a geographical area and cells in carrier aggregation, in this disclosure, cells in carrier aggregation are referred to as CCs, and cells representing a geographical area are referred to as cells.

[0138] Figure 10 This diagram illustrates an example of cross-carrier scheduling technology. When cross-carrier scheduling is set up, the control channel transmitted via the first CC can use the Carrier Indicator Field (CIF) to schedule the data channel transmitted via either the first CC or the second CC. The CIF is included in the DCI. In other words, a scheduling cell is set up, and the DL license / UL license transmitted in the PDCCH area of ​​that scheduling cell schedules the PDSCH / PUSCH of the scheduled cell. That is, there is a search area for multiple component carriers in the PDCCH area of ​​the scheduling cell. A PCell can essentially be a scheduling cell, and a specific SCell can be designated as a scheduling cell by a higher layer.

[0139] exist Figure 10In the embodiment, it is assumed that three DL CCs are combined. Here, it is assumed that DL component carrier #0 is a DLPCC (or PCell), and DL component carriers #1 and #2 are DL SCCs (or SCells). Furthermore, it is assumed that the DLPCC is configured as a PDCCH monitoring CC. When cross-carrier scheduling is not configured via UE-specific (or UE group-specific or cell-specific) higher-layer signaling, CIF is disabled, and each DL CC can transmit only the PDCCH for scheduling its PDSCH according to the NR PDCCH rules without CIF (non-cross-carrier scheduling, self-carrier scheduling). Meanwhile, if cross-carrier scheduling is configured via UE-specific (or UE group-specific or cell-specific) higher-layer signaling, CIF is enabled, and a specific CC (e.g., DL PCC) can use CIF to transmit not only the PDCCH for scheduling DL CC A but also the PDCCH for scheduling another CC (cross-carrier scheduling). On the other hand, no PDCCH is transmitted in another DL CC. Therefore, the UE monitors the PDCCH excluding CIF to receive the PDSCH scheduled by the carrier, or monitors the PDCCH including CIF to receive the PDSCH scheduled by the carrier, depending on whether cross-carrier scheduling is configured for the UE.

[0140] on the other hand, Figure 9 and Figure 10 The diagram illustrates the subframe structure of a 3GPP LTE-A system, and the same or similar configuration can be applied to a 3GPP NR system. However, in a 3GPP NR system, Figure 9 and Figure 10 Subframes can be replaced with time slots.

[0141] As mentioned above, since existing communications in unlicensed frequency bands primarily operate based on LBT (Low-Level Transmission), channel access in NR-U systems also implements LBT to coexist with existing equipment. Specifically, based on the presence / absence / application method of LBT, channel access methods in unlicensed frequency bands in NR can be classified into the following four categories.

[0142] Category 1: No LBT

[0143] -Tx entities do not perform the LBT procedure for transmission.

[0144] Category 2: LBT without random backoff

[0145] The Tx entity senses whether the channel is idle during the first interval without random backoff to perform a transmission. That is, the Tx entity can perform a transmission through the channel immediately after sensing that the channel is idle during the first interval. The first interval is a predetermined length of interval immediately following the Tx entity's transmission. According to an embodiment, the first interval may be a 25 μs interval, but the invention is not limited thereto.

[0146] Category 3: LBT with random backoff performed using a fixed-size CW

[0147] The Tx entity obtains a random value within a fixed-size CW, sets it as the initial value N of a backoff counter (or backoff timer), and performs backoff using the set backoff counter N. During the backoff process, the Tx entity decrements the backoff counter by 1 whenever the channel is detected to be idle within a predetermined time slot period. Here, the predetermined time slot period can be 9 μs, but the invention is not limited to this. The backoff counter N is decremented from its initial value by 1, and the Tx entity can perform transmission when the value of the backoff counter N reaches 0. Simultaneously, in order to perform backoff, the Tx entity first senses the second interval (i.e., the delay duration T). d The Tx entity can sense (determine) whether the channel is idle during the second interval based on whether the channel is idle during at least some time periods (e.g., a time slot period) within the second interval. The second interval can be set based on the channel access priority level of the Tx entity and consists of a 16μs time period and m consecutive time slot periods. Here, m is a value set according to the channel access priority level. When the channel is sensed to be idle during the second interval, the Tx entity performs channel sensing to reduce the backoff counter. On the other hand, when the channel is sensed to be busy during the backoff process, the backoff process stops. After stopping the backoff process, the Tx entity can resume backoff when the channel is sensed to be idle within the additional second interval. In this way, in addition to the second interval, the Tx entity can also perform transmission when the channel is idle during the time slot period of the backoff counter N. In this case, the initial value of the backoff counter N is obtained within a fixed-size CW.

[0148] Category 4: LBT performs random backoff by using a variable-size CW

[0149] The Tx entity acquires a random value within a variable-sized CW, sets this random value as the initial value of the backoff counter (or backoff timer) N, and performs backoff using the set backoff counter N. More specifically, the Tx entity can adjust the size of the CW based on HARQ-ACK information for previously transmitted data, and acquire the initial value of the backoff counter N within the adjusted-size CW. The specific process for the Tx entity to perform backoff is as described in Category 3. Except for the second interval, the Tx entity can perform transmissions when the channel is idle during the time slot period of the backoff counter N. In this case, the initial value of the backoff counter N is acquired within the variable-sized CW.

[0150] In categories 1 to 4 above, the Tx entity can be a base station or a UE. According to an embodiment of the present invention, the first type of channel access can refer to channel access of category 4, and the second type of channel access can refer to channel access of category 2.

[0151] Figure 11 This is a diagram illustrating the positions of OFDM symbols occupied by SSBs within multiple time slots of the licensed frequency band of the NR system according to an embodiment of the present invention.

[0152] The SSB can include four OFDM symbols and 20 RBs. Specifically, the PSS can occupy one OFDM symbol, the SSS can occupy one OFDM symbol, and the PBCH can occupy two OFDM symbols and one OFDM symbol multiplexed with the SSS via FDM. The OFDM symbol position within the time slot occupied by the SSB can be changed according to the subcarrier spacing (SCS). Figure 11 (a) shows the SSB pattern when the subcarrier spacing used for SSB transmission is 15 kHz and 30 kHz. Figure 11 (b) shows the SSB patterns when the subcarrier spacing used for SSB transmission is 120 kHz and 240 kHz. When the subcarrier spacing is 30 kHz, the SSB pattern used for eMBB transmission or the SSB pattern considering URLLC can be used. Figure 11 In the diagram, the shaded OFDM symbol indicates the position of the OFDM symbol in the time slot occupied by the SSB. Furthermore, different shaded patterns indicate different SSB indices.

[0153] Figure 12 This is a diagram illustrating the position of the time slot occupied by the SSB within a 5ms segment of the licensed frequency band of the NR system according to an embodiment of the present invention. Figure 12In the text, the shadowed slot indicates the location of the slot containing the SSB within the half-radio frame. A slot can contain two SSBs. Two SSBs within a slot can have different SSB indices. Furthermore, SSBs located in different slots can also have different SSB indices. SSB indices will be described again later. Additionally, in... Figure 12 In this context, L represents the maximum number of SSBs that a base station can transmit in a semi-radio frame.

[0154] The NR system specifies a subcarrier spacing for each frequency band to reduce the complexity of the UE searching for the SSB used for initial cell access. Specifically, when using frequency bands below 6 GHz, the NR system specifies a subcarrier spacing of 15 kHz and 30 kHz for the SSB. Conversely, when using frequency bands above 6 GHz, the NR system specifies a subcarrier spacing of 120 kHz and 240 kHz for the SSB.

[0155] When a wireless communication device performs channel access in an unlicensed frequency band, the LBT procedure can be used. Therefore, if the channel is not idle, the wireless communication device may be unable to perform channel access. Even when the base station performs channel access to transmit an SSB, channel access may fail. Therefore, SSB transmission may not occur at the location configured by the base station. Ultimately, even if the base station configures the location for transmitting SSBs for the UE, allowing the UE to assume the location, the UE may still fail to receive the SSB. SSBs are transmitted periodically. Therefore, even if the UE fails to receive an SSB at one point in time, the UE can receive the SSB one period later from the corresponding time point. However, if the UE receives the SSB as described above, delays may occur in RRM measurements and neighboring cell measurements. Ultimately, the overall system latency will increase.

[0156] Additionally, SSBs are used for beam link configuration and beam management. Specifically, the base station transmits multiple SSBs corresponding to different SSB indices in different time zones. The UE configures multiple beam links using multiple SSBs. The base station performs beam scanning. The UE can configure beam links based on whether it has received SSBs transmitted through different beams in different time zones. If the base station fails to access the channel, preventing the transmission of SSBs, the UE will be unable to configure beam links. Ultimately, beam link latency increases due to channel access failure. Therefore, a method is needed to reduce the number of SSB transmission failures and increase SSB transmission opportunities.

[0157] When using NR systems in unlicensed frequency bands, a 60kHz subcarrier spacing can be used for SSB transmission to increase channel access opportunities. A 15kHz or 30kHz subcarrier spacing can be used for SSB transmission in licensed frequency bands below 6GHz. Furthermore, 15kHz, 30kHz, or 60kHz subcarrier spacings can be used for data transmission in licensed frequency bands below 6GHz. Additionally, a 120kHz or 240kHz subcarrier spacing can be used for SSB transmission in licensed frequency bands above 6GHz. Furthermore, a 60kHz or 120kHz subcarrier spacing can be used for data transmission in licensed frequency bands above 6GHz. When NR systems are used in unlicensed frequency bands below 7GHz (e.g., below 7.125GHz), a 15kHz or 30kHz subcarrier spacing can be considered, which is the same as the subcarrier spacing used in licensed frequency bands below 6GHz. However, if a 60kHz subcarrier spacing is used for SSB transmission in unlicensed frequency bands, the OFDM symbol duration is one-quarter of that when using a 15kHz subcarrier spacing. Therefore, when a 60kHz subcarrier spacing is used in an NR system in an unlicensed frequency band, the transmission opportunities for SSBs and data channels on a symbol-by-symbol basis can be increased after channel access. When using a 60kHz subcarrier spacing, the time required for a base station to successfully transmit reserved signals in an OFDM symbol when achieving channel access may be less than when using 15kHz and 30kHz subcarrier spacings.

[0158] NR-U DRS (or DRS) configuration

[0159] In the unlicensed frequency bands of an NR system, a base station may transmit signals including at least one SSB transmission or at least one SSB burst set transmission. An SSB burst set indicates continuous transmission of SSBs within a predetermined time interval. In this case, the signal may correspond to a Discovery Signal Burst (DRS burst). The base station may transmit DRS bursts according to the following principles: The base station may transmit DRS bursts such that the time interval for transmitting the DRS burst within the beam does not include gaps. The base station may transmit DRS bursts to satisfy the Occupied Channel Bandwidth (OCB) condition. However, the base station may transmit DRS bursts that do not satisfy the Occupied Channel Bandwidth condition in certain situations. Additionally, the base station may consider methods to minimize the channel occupancy time of the DRS burst and implement fast channel access. For ease of explanation, DRS will be used instead of DRS burst.

[0160] A DRS transmitted in an unlicensed frequency band may include a PDSCH containing SSB-related Residual System Information (RMSI) (i.e., System Information Block 1 (SIB1)). Furthermore, the DRS may include an RMSI-CORESET, which is a time and frequency resource area associated with the control channel for transmitting scheduling information used to transmit the RMSI. That is, the DRS may include a CORESET, which is a time and frequency area for transmitting a PDCCH that schedules the PDCSH including SIB1. Additionally, the DRS may include CSI-RS. Furthermore, the DRS may include different types of signals. Specifically, the DRS may include other System Information (OSI) or paging. As mentioned above, when a base station transmits a DRS in an unlicensed frequency band, the base station may multiplex the DRS with physical channels or signals. In this case, the method by which the base station performs channel access is problematic. Specifically, it is problematic which method the base station uses among the various channel access methods described above, and by which method the parameters for channel access are configured. Furthermore, the DRS may include the transmission of an SSB or an SSB burst set.

[0161] In embodiments of the present invention, when a base station multiplexes DRS and unicast data, the base station can perform channel access where a variable-sized Channel Warp (CW) is used for random backoff and the size of the CW is determined according to the channel access priority level, in order to perform the transmission of the multiplexed DRS and unicast data. The UE can perform channel access according to the channel access priority level of the multiplexed unicast data. Specifically, the channel access method can correspond to the first type of channel access described above.

[0162] In these embodiments, the scenario where the base station multiplexes DRS with signals or information other than unicast data will be described. Signals or information other than unicast data may indicate signals or channels that are not data services, and therefore it is not possible to configure a channel access priority level for such signals or channels. Signals or information other than unicast data may include control messages associated with initial access, random access, mobility, or paging. Furthermore, signals or information other than unicast data may include transmissions that only include reference signals. Additionally, signals or information other than unicast data may include transmissions that only include PDCCH. Transmissions that only include PDCCH may include at least one of RACH message 4 under a random access procedure, a handover command, a group common PDCCH, a short paging message, other system information (OSI), a paging response, and a random access response (RAR). Furthermore, signals or information other than unicast data may also be transmitted via PDCCH and PDSCH. For ease of explanation, signals or information other than unicast data will be referred to as non-unicast data. Additionally, in this specification, multiplexed DRS and non-unicast data may indicate that unicast data is not included in the corresponding transmission. In a detailed embodiment, when the base station multiplexes DRS with non-unicast data, the base station can perform channel access where only LBT based on a single time interval is performed, in order to transmit the multiplexed DRS and non-unicast data. This channel access where only LBT based on a single time interval is performed can be the second type of channel access described above. The duration of the single time interval can be 25 μs or 34 μs.

[0163] In another detailed embodiment, when the base station multiplexes DRS with non-unicast data, the base station can perform channel access where random back-off is performed using a variable-sized CW and the CW size is determined according to the channel access priority level, in order to perform the transmission of multiplexed DRS and non-unicast data. In this embodiment, it is considered that LBT based on a single time interval is performed only when the entire duration of the transmission consisting solely of DRS is less than or equal to 1 ms, and the duty cycle of the DRS transmission is less than or equal to 1 / 20. In this embodiment, the base station can use the channel access priority level with the highest priority (e.g., channel access priority level #1). Therefore, the base station can assign a higher channel access priority to non-unicast data compared to unicast data. Additionally, the base station can use the channel access priority level with the highest priority and the smallest CW size allowed within that channel access priority level. In another detailed embodiment, the base station can use the channel access priority level with the highest priority and the largest CW size allowed within that channel access priority level.

[0164] In another detailed embodiment, when the base station multiplexes DRS with non-unicast data, the base station can perform channel access with random backoff using a fixed-size CW to enable transmission of the multiplexed DRS and non-unicast data. The channel access method can be the Category 3 channel access described above. In this embodiment, the base station can use the channel access priority level with the highest priority (e.g., channel access priority level #1). Therefore, the base station can assign a higher channel access priority to non-unicast data compared to unicast data. Additionally, the base station can use the channel access priority level with the highest priority and the smallest CW size allowed within that channel access priority level. In another detailed embodiment, the base station can use the channel access priority level with the highest priority and the largest CW size allowed within that channel access priority level.

[0165] When a base station transmits non-unicast data that is not multiplexed with a DRS, the base station can perform channel access for transmitting the non-unicast data by using the channel access method used when multiplexing non-unicast data and a DRS. Specifically, when a base station transmits non-unicast data that is not multiplexed with a DRS, the base station can use the channel access type and channel access parameters used when multiplexing non-unicast data and a DRS.

[0166] In another detailed embodiment, when a base station transmits non-unicast data not multiplexed with a DRS, the base station can perform channel access in which random back-off is performed using a variable-size Channel Warp (CW) and the CW size is determined according to the channel access priority level, in order to perform the transmission of non-unicast data. Specifically, the channel access method can correspond to the first type of channel access described above. In this embodiment, the base station can use the channel access priority level with the highest priority (e.g., channel access priority level #1). Therefore, the base station can assign a higher channel access priority to non-unicast data compared to unicast data. Furthermore, the base station can use the channel access priority level with the highest priority and use the smallest CW size allowed within that channel access priority level. In another detailed embodiment, the base station can use the channel access priority level with the highest priority and use the largest CW size allowed within that channel access priority level.

[0167] In another detailed embodiment, when a base station transmits non-unicast data not multiplexed with a DRS, the base station can perform channel access with random backoff using a fixed-size CW to enable the transmission of the non-unicast data. The channel access method can be the Category 3 channel access described above. In this embodiment, the base station can use the channel access priority level with the highest priority (e.g., channel access priority level #1). Therefore, the base station can assign a higher channel access priority to non-unicast data compared to unicast data. Furthermore, the base station can use the channel access priority level with the highest priority and the smallest CW size allowed within that channel access priority level. In another detailed embodiment, the base station can use the channel access priority level with the highest priority and the largest CW size allowed within that channel access priority level.

[0168] In the above embodiments, the base station determines the channel access method for transmitting multiplexed DRS and non-unicast or unicast data, regardless of the transmission duration of the multiplexed DRS and non-unicast or unicast data, or the duty cycle of the DRS transmission. When determining the channel access method, the base station may assume that the transmission of only DRS and the transmission of multiplexed DRS and non-unicast data are the same. Specifically, the base station may determine the channel access method for transmitting multiplexed DRS and non-unicast or unicast data based on the transmission duration of the multiplexed DRS and non-unicast or unicast data, and the duty cycle of the DRS transmission. The base station may determine the channel access method for transmitting multiplexed DRS and non-unicast or unicast data based on whether the transmission duration of the multiplexed DRS and non-unicast or unicast data is less than or equal to 1 ms, and whether the duty cycle of the DRS transmission is less than or equal to 1 / 20.

[0169] When a base station performs the transmission of multiplexed DRS and non-unicast data, it can select one of two channel access types based on whether two conditions are met: the duration of the multiplexed DRS and non-unicast data transmission is less than or equal to 1 ms, and the duty cycle of the DRS transmission is less than or equal to 1 / 20. One of the two channel access types indicates channel access in which only LBT based on a single time interval is performed, while the other indicates channel access in which random backoff is performed using a variable-size CW, and the size of the CW is determined according to the channel access priority level. In a detailed embodiment, if the duration of the multiplexed DRS and non-unicast data transmission is less than or equal to 1 ms, or the duty cycle of the DRS transmission is less than or equal to 1 / 20, the base station can perform channel access in which only LBT based on a single time interval is performed to perform the transmission of multiplexed DRS and non-unicast data. The duration of the single time interval can be 25 μs. Alternatively, LBT based on a single time interval can correspond to the second type of channel access described above. In another detailed embodiment, if the transmission duration of the multiplexed DRS and non-unicast data is greater than 1 ms, or the duty cycle of the DRS transmission is greater than 1 / 20, the base station can perform channel access in which random backoff is performed using a variable-size CW and the CW size is determined according to the channel access priority level, in order to perform the transmission of the multiplexed DRS and non-unicast data. Furthermore, the base station can select a random channel access priority level. The base station can randomly select one of the channel access priority levels that satisfies the MCOT length condition based on the transmission duration of the multiplexed DRS and non-unicast data. The base station can use the selected channel access priority level for channel access to transmit the multiplexed DRS and non-unicast data. That is, the base station can use the CW size according to the selected channel access priority level for channel access. For example, the base station can use the channel access priority level with the highest priority (e.g., channel access priority level #1). Therefore, the base station can assign a higher channel access priority to non-unicast data compared to unicast data. Furthermore, the base station can use the channel access priority level with the highest priority and use the smallest CW size allowed in that channel access priority level. In another detailed embodiment, the base station may use a channel access priority level with the highest priority, and use the maximum CW size among the CW sizes allowed in that channel access priority level.

[0170] In the above embodiments, when the base station can determine whether the UE has received non-unicast data and whether the reception was successful, the base station can adjust the CW size based on the ratio between ACK and NACK. Specifically, the base station can convert feedback information about the non-unicast data received from the UE according to the UE's reception into ACK and NACK, and can adjust the CW size based on the ratio between ACK and NACK. The channel access method that uses a variable-sized CW to perform random backoff and determines the CW size according to the channel access priority level can correspond to the first type of channel access.

[0171] As described above, the base station and UE can control the CW size based on HARQ feedback when using CW for channel access. However, the base station and UE may not anticipate HARQ feedback for all or part of the non-unicast data. Additionally, the base station and UE may not be able to determine whether the UE or the base station has received all or part of the non-unicast data. Furthermore, when the base station and UE are required to perform an initial access procedure, they may not be able to determine the HARQ-ACK feedback regarding the portion of downlink signals and channels used during the initial access procedure, as well as the uplink signals and channels. Furthermore, the base station and UE may not perform transmissions associated with a specific channel access priority level, and therefore may not be able to determine the HARQ-ACK feedback corresponding to the transmission associated with the corresponding channel access priority level. In this case, a method for the base station and UE to determine the CW, which will be used for channel access when transmitting channels and signals including all or part of the non-unicast data for which HARQ feedback is not expected, will be described. For ease of explanation, the base station is interpreted as the subject, but the embodiments described below can also be applied to the UE in the same manner.

[0172] When a base station cannot determine HARQ-ACK feedback regarding a transmission associated with a channel access priority level that determines the CW size, the base station may perform channel access, wherein random backoff is performed in the CW corresponding to the channel access priority. The base station may use the smallest CW size allowed in the corresponding channel access priority level. In another detailed embodiment, the base station may use the channel access priority level with the highest priority and the largest CW size allowed in that channel access priority level.

[0173] Furthermore, if the base station cannot determine whether the UE has received all or part of the non-unicast data for which HARQ feedback is not expected, the base station can perform channel access with random backoff within a fixed CW size to transmit multiplexed non-unicast data and DRS. Specifically, the base station can use a CW corresponding to a channel access priority level during the first type of channel access described above. In a detailed embodiment, the base station can use one of the channel access priority levels that satisfy the MCOT length condition during the first type of channel access, based on the duration of the multiplexed DRS and non-unicast data transmission. The base station can use the channel access priority level with the highest priority. In a detailed embodiment, the base station can use the channel access priority level with the highest priority among the channel access priority levels that satisfy the MCOT length condition during the first type of channel access, based on the duration of the multiplexed DRS and non-unicast data transmission. Additionally, the base station can use the channel access priority level with the highest priority and the smallest CW size allowed within that channel access priority level. In another detailed embodiment, the base station can use the channel access priority level with the highest priority and the largest CW size allowed within that channel access priority level.

[0174] In another detailed embodiment, if the base station cannot determine whether the UE has received all or part of the non-unicast data for which HARQ feedback is not expected, the base station may perform Category-3 channel access as described above to transmit multiplexed non-unicast data and DRS. The base station may use the channel access priority level with the highest priority. The base station may use the channel access priority level with the highest priority among those satisfying the MCOT length condition, based on the duration of the transmission of the multiplexed DRS and non-unicast data. Additionally, the base station may use the channel access priority level with the highest priority and the smallest CW size allowed within that channel access priority level. In another detailed embodiment, the base station may use the channel access priority level with the highest priority and the largest CW size allowed within that channel access priority level.

[0175] A base station may be unable to transmit an SSB due to a channel access (e.g., LBT) procedure failure. When a base station cannot transmit an SSB at a configured location, an SSB transmission window can be defined, allowing the SSB to be transmitted at another location. The SSB transmission window is a time interval within which the base station can transmit an SSB and includes multiple SSB transmission location candidates. When a base station fails to initiate SSB transmission at a candidate SSB transmission location, it can attempt to transmit an SSB at a later candidate SSB transmission location within the SSB transmission window. A candidate SSB transmission location is a point in time when the base station can initiate SSB transmission. When a user equipment (UE) fails to receive an SSB at a candidate SSB transmission location within the SSB transmission window, the UE can receive an SSB at a later candidate SSB transmission location within the SSB transmission window. Here, the UE can determine whether the base station is unable to initiate SSB transmission or whether the base station's SSB transmission has failed at a candidate SSB transmission location. In a particular embodiment, when a user equipment (UE) fails to receive an SSB at a candidate SSB transmission location within an SSB transmission window, the UE may attempt to receive an SSB at an adjacent candidate SSB transmission location within the same SSB transmission window. After completing the reception of an SSB at a candidate SSB transmission location, the UE may not expect to receive additional SSBs within the corresponding SSB transmission window. Specifically, after completing the reception of an SSB at a candidate SSB transmission location, the UE may not attempt to receive additional SSBs within the corresponding SSB transmission window.

[0176] In another specific embodiment, when a user equipment fails to receive a specific SSB at a candidate SSB transmission location within an SSB transmission window, the user equipment may attempt to receive the specific SSB at an adjacent candidate SSB transmission location within the same SSB transmission window. After completing the reception of the specific SSB at a candidate SSB transmission location, the user equipment may not perform reception of the specific SSB within the corresponding SSB transmission window. Specifically, after receiving a specific SSB at a candidate SSB transmission location, the user equipment may, without additional intent, attempt to receive the specific SSB within the corresponding SSB transmission window.

[0177] In another specific embodiment, even after receiving a specific SSB at a candidate SSB transmission location, the user equipment can still attempt to receive the specific SSB within the corresponding SSB transmission window. This is because the user equipment can additionally receive the specific SSB and obtain combined gain through the additionally received specific SSB. These embodiments can be applied not only to cases where multiple SSBs corresponding to different beam indices are transmitted for beam operation, but also to cases where an omnidirectional transmission (omni-TX) scheme is used. Specifically, the embodiments can also be applied to cases where the same SSB is repeatedly transmitted.

[0178] LBT method of DRS

[0179] Figure 13 This is a diagram illustrating the position of OFDM symbols occupied by SSBs within a time slot comprising 14 OFDM symbols according to an embodiment of the present invention.

[0180] In the following text, reference will be made to Figure 13 This describes a channel access method for a DRS that includes at least one SSB. Specifically, the method described below is a channel access method performed by the base station before transmitting the DRS, based on the number of SSBs included in the DRS to be transmitted from the base station; that is, a configuration method for performing different LBTs.

[0181] Figure 13 The diagram illustrates the positions of OFDM symbols occupied by the SSB within a time slot configured with 14 OFDM symbols. SSB pattern A is identical to the positions of OFDM symbols occupied by the SSB of the NR system as defined in 3GPP Rel.15. In SSB pattern B, the OFDM symbols occupied by the SSB in the latter half of a time slot are positioned one symbol after those in SSB pattern A. Therefore, SSB pattern B is configured such that the positions of OFDM symbols occupied by the SSB within a time slot are symmetrical to each other on a half-time slot basis.

[0182] If the total duration of the transmission including DRS is greater than or equal to 1 ms, the base station can perform multiple transmissions and determine the channel access method for each of the multiple DRS transmissions.

[0183] If unlicensed frequency bands (such as the 5GHz or 6GHz band) are used, the base station can transmit a maximum of n SSBs in the DRS. The value of n can be 2, 4, or 8. Additionally, the subcarrier spacing used for DRS transmission can be 15kHz or 30kHz. If the subcarrier spacing is 15kHz, the duration of one time slot can be 1ms, and the number of SSBs that can be included in a 1ms interval can be 2. Alternatively, if the subcarrier spacing is 30kHz, the duration of one time slot can be 0.5ms, and the number of SSBs that can be included in a 1ms interval may be 4. The total duration of DRS transmission with a duty cycle of 1 / 20 may vary depending on the DRS transmission cycle configuration.

[0184] As described above, the total duration of the transmission including DRS can be less than or equal to 1 ms, and the duty cycle of the DRS transmission can be less than or equal to 1 / 20. When the base station performs transmission including only DRS or multiplexed DRS and non-unicast data, for the corresponding transmission, the base station can perform channel access where only LBT based on a single time interval is performed. Channel access where only LBT based on a single time interval is performed can be the second type of channel access described above. The total duration of the transmission including DRS may be greater than 1 ms, and the duty cycle of the DRS transmission may be greater than 1 / 20. When the base station performs transmission including only DRS or multiplexed DRS and non-unicast data, the base station can perform channel access where random backoff is performed using a variable-sized CW, and the size of the CW is determined according to the channel access priority level, in order to perform the corresponding transmission. The channel access method where random backoff is performed using a variable-sized CW, and the size of the CW is determined according to the channel access priority level, can correspond to the first type of channel access.

[0185] In the embodiments of this disclosure, considering the characteristics of transmissions including DRS, a method of LBT based on a single time interval can be used, performed by the base station. If the total duration of the transmissions including DRS is greater than 1 ms, the base station can determine the channel access method in units of 1 ms duration. Specifically, if the total duration of the transmissions including DRS is greater than 1 ms, the base station can perform multiple transmissions, each with a duration less than or equal to 1 ms, and for each of the multiple transmissions, channel access consisting only of LBT based on a single time interval can be performed. The base station can apply this embodiment only when the duty cycle of the DRS transmission is less than or equal to 1 / 20. This is because, in the absence of LBT for transmission, there is an ETSI requirement that short control signals must not exceed 5% of the corresponding transmission. Through the above embodiments, the base station and UE can quickly perform initial access and RRM measurements using the SSB included in the DRS transmitted from the base station. For example, when the DRS transmission period is configured to be equal to or greater than 40ms, and the base station performs DRS transmission within a 5ms interval configured as a DRS transmission window in each minimum 40ms period unit, the total duration of the DRS transmission, including the condition that the duty cycle of the DRS transmission is less than or equal to 1 / 20, can be less than or equal to 2ms. Under the constraint that the total duration of the transmission, including DRS, is less than or equal to 2ms, the base station can perform multiple DRS transmissions, each with a duration less than or equal to 1ms. Before each of the multiple transmissions, the base station can perform second-type channel access. Through this embodiment, the base station can quickly perform DRS transmissions to the UE. Additionally, when the DRS transmission period is configured to be greater than or equal to 80ms, and the base station performs DRS transmission within a 5ms interval configured as a DRS transmission window in each minimum 80ms period unit, the total duration of the DRS transmission, including the condition that the duty cycle of the DRS transmission is less than or equal to 1 / 20, can be less than or equal to 4ms. With a total transmission duration including DRS less than or equal to 4 ms, a base station can perform multiple DRS transmissions, each with a duration of less than or equal to 1 ms. The base station can perform Type II channel access before each of the multiple transmissions.

[0186] Additionally, if the total duration of the transmission including DRS is greater than 1 ms, and the duty cycle of the DRS transmission is greater than 1 / 20, the base station can perform channel access in which random back-off is performed using a variable-size CW, and the size of the CW is determined according to the channel access priority level, in order to perform the transmission including DRS. This channel access method can correspond to the first type of channel access.

[0187] In another detailed embodiment, a portion of the transmission interval including DRS may have a transmission duty cycle less than or equal to 1 / 20. The base station may perform channel access, where only LBT based on a single time interval is performed, for a portion of the transmission interval including DRS with a duty cycle less than or equal to 1 / 20. Alternatively, in this embodiment, the base station may perform multiple transmissions, each with a duration less than or equal to 1 ms, and may perform channel access, including only LBT based on a single time interval, for each of the multiple transmissions. Channel access performing only LBT based on a single time interval may be a second type of channel access. Additionally, the base station may perform channel access, where random backoff is performed using a variable-size CW and the size of the CW is determined according to a channel access priority level, for the remaining transmission intervals including DRS. Channel access using a variable-size CW with random backoff and the size of the CW determined according to a channel access priority level may be a first type of channel access. For example, the period of the DRS transmission may be a multiple of 20 ms. Specifically, if the DRS transmission period is 20ms, the duration of the transmission interval with a duty cycle less than or equal to 1 / 20 is 1ms. If the DRS transmission period is 40ms, the duration of the transmission interval with a duty cycle less than or equal to 1 / 20 is 2ms. If the DRS transmission period is 60ms, the duration of the transmission interval with a duty cycle less than or equal to 1 / 20 is 3ms. If the DRS transmission period is 80ms, the duration of the transmission interval with a duty cycle less than or equal to 1 / 20 is 4ms. The base station can perform second-type channel access for a portion of the transmission intervals that include DRS transmissions with a duty cycle of 1 / 20, and can perform first-type channel access for the remaining transmission intervals that include DRS transmissions.

[0188] The maximum number of SSBs included in the DRS can be 8. Assuming the number of SSBs included in the DRS is 8, the following description is given: If the DRS transmission period is 20ms, then the duration of the transmission interval where the DRS transmission duty cycle is less than or equal to 1 / 20 is 1ms. Therefore, if the subcarrier spacing is 15kHz, then two SSBs are included in the transmission interval where the DRS transmission duty cycle is less than or equal to 1 / 20. The base station can perform a second type of channel access before performing the first transmission, and if the channel access is successful, the base station can transmit two SSBs. Alternatively, the base station can perform a first type of channel access before performing the second transmission, and if the channel access is successful, the base station can transmit 6 SSBs. Furthermore, if the DRS transmission period is 20ms, then the duration of the transmission interval where the DRS transmission duty cycle is less than or equal to 1 / 20 is 1ms. Therefore, if the subcarrier spacing is 30kHz, then four SSBs can be included in the transmission interval where the DRS transmission duty cycle is less than or equal to 1 / 20. The base station can perform second-type channel access before performing the first transmission. If the channel access is successful, the base station can send four SSBs. Alternatively, the base station can perform first-type channel access before performing the second transmission, and if the channel access is successful, the base station can send four SSBs.

[0189] If the DRS transmission period is 40ms, then the duration of the transmission interval with a duty cycle less than or equal to 1 / 20 is 2ms. Therefore, if the subcarrier spacing is 15kHz, then the transmission interval with a duty cycle less than or equal to 1 / 20 of the DRS transmission may include 4 SSBs. The base station can perform two transmissions with a duration of 1ms each, and can send two SSBs in each transmission. The base station can perform a second type of channel access before performing the first transmission, and if the channel access is successful, the base station can send two SSBs. Additionally, the base station can perform a second type of channel access before performing the second transmission, and if the channel access is successful, the base station can send two SSBs. Furthermore, the base station can perform a first type of channel access before performing the third transmission, and if the channel access is successful, the base station can send the remaining 4 SSBs. Also, if the DRS transmission period is 40ms, then the duration of the transmission interval with a duty cycle less than or equal to 1 / 20 of the DRS transmission is 2ms. Therefore, if the subcarrier spacing is 30 kHz, then the transmission interval in which the duty cycle of DRS transmission is less than or equal to 1 / 20 can include 8 SSBs. The base station can perform second-type channel access before performing the first transmission; if channel access is successful, the base station can transmit 4 SSBs. Alternatively, the base station can perform second-type channel access before performing the second transmission, and if channel access is successful, the base station can transmit 4 SSBs.

[0190] In another detailed embodiment, the portion of the transmission interval including the DRS may have a duration of less than or equal to 1 ms and a DRS transmission duty cycle of less than or equal to 1 / 20. The base station may perform channel access for the portion of the transmission interval including a DRS with a duty cycle of less than or equal to 1 / 20 and a duration of less than or equal to 1 ms, wherein only LBT based on a single time interval is performed. Performing channel access where only LBT based on a single time interval is performed can be a second type of channel access. Alternatively, the base station may perform channel access for the remaining transmission intervals where random backoff is performed using a variable-size CW and the size of the CW is determined according to a channel access priority level. Channel access using a variable-size CW and performing random backoff and determining the size of the CW according to a channel access priority level can be a first type of channel access.

[0191] The maximum number of SSBs that can be included in a DRS is 8. The following description assumes that the number of SSBs included in the DRS is 8.

[0192] If the DRS transmission period is 20ms, then the duration of the transmission interval with a duty cycle less than or equal to 1 / 20 is 1ms. Therefore, if the subcarrier spacing is 15kHz, the transmission interval with a duty cycle less than or equal to 1 / 20 can include two SSBs. The base station can perform second-type channel access before performing the first transmission, and if the channel access is successful, the base station can send two SSBs. Alternatively, the base station can perform first-type channel access before performing the second transmission, and if the channel access is successful, the base station can send six SSBs. Furthermore, if the DRS transmission period is 20ms, then the duration of the transmission interval with a duty cycle less than or equal to 1 / 20 is 1ms. Therefore, if the subcarrier spacing is 30kHz, the transmission interval with a duty cycle less than or equal to 1 / 20 can include four SSBs. The base station can perform second-type channel access before performing the first transmission, and if the channel access is successful, the base station can send four SSBs. In addition, the base station can perform first-type channel access before performing the second transmission. If the channel access is successful, the base station can send four SSBs.

[0193] If the DRS transmission period is 40ms, then the duration of the transmission interval with a DRS transmission duty cycle less than or equal to 1 / 20 is 2ms. If the subcarrier spacing is 15kHz, then a transmission interval with a duration of 1ms and a DRS transmission duty cycle less than or equal to 1 / 20 can include two SSBs. The base station can perform second-type channel access before performing the first transmission; if channel access is successful, the base station can send two SSBs. Additionally, the base station can perform first-type channel access before performing the second transmission; if channel access is successful, the base station can send the remaining 6 SSBs. Furthermore, if the DRS transmission period is 40ms, then the duration of the transmission interval with a DRS transmission duty cycle less than or equal to 1 / 20 is 2ms. If the subcarrier spacing is 30kHz, then a transmission interval with a duration of 1ms and a DRS transmission duty cycle less than or equal to 1 / 20 can include four SSBs. The base station can perform second-type channel access before performing the first transmission; if channel access is successful, the base station can send 4 SSBs. In addition, the base station can perform the first type of channel access before performing the second transmission. If the channel access is successful, the base station can send four SSBs.

[0194] Additionally, the DRS transmission window duration can be configured as Tms. T can be a natural number greater than or equal to 1. T can be 5 or 6. Alternatively, T can be configured as a multiple of the minimum time interval in which the maximum number of available SSBs included in the DRS can be included. If the duration of the DRS transmission window is greater than or equal to 1ms, the base station can perform channel access in which only LBT based on a single time interval is performed before the last 1ms of the DRS transmission window. If the DRS transmission duty cycle in the last 1ms of the DRS transmission window is less than or equal to 1 / 20, the base station can perform channel access in which only LBT based on a single time interval is performed before the last 1ms of the DRS transmission window. Performing channel access in which only LBT based on a single time interval is performed can be the second type of channel access described above. Alternatively, the base station can perform either the first type of channel access or the second type of channel access before the last 1ms of the DRS transmission window. Through these embodiments, the UE can quickly perform initial access and RRM measurements.

[0195] The LBT process used by a wireless communication device when performing channel access in an unlicensed frequency band, according to an embodiment of the present invention, will be described below. Specifically, the wireless communication device can be configured to perform channel access based on the results of channel sensing within a time interval of a pre-specified duration. A method for operating the wireless communication device when channel access fails will be described. The pre-specified duration may be 16 μs.

[0196] For convenience, the wireless communication device that initiates channel occupancy is referred to as the initiating node. Furthermore, the wireless communication device that communicates with the initiating node is referred to as the responding node. The initiating node can be a base station, and the responding node can be a user equipment (UE). When the initiating node attempts to transmit data, it can perform channel access based on a channel access priority level determined by the data type. Here, the parameters used in channel access can be determined based on the data type. The parameters used in channel access may include at least one of the following: a minimum CW, a maximum CW, a maximum channel occupancy time (MCOT) as the maximum duration of a single channel occupancy, or the number of sensing time slots (m). p In detail, the initiating node can perform the above-mentioned category 4LBT according to the channel access priority level determined based on the data type.

[0197] Table 4 below shows examples of parameter values ​​used in channel access according to the channel access priority level. Specifically, Table 4 shows the values ​​of parameters used in channel access for each channel access priority level for downlink transmission in an LTE LAA system.

[0198] When the downlink channel transmitted by a wireless communication device includes data services, the delay duration can be configured according to the channel access priority level of the services included in the downlink channel. Furthermore, the delay duration may include the initial interval T. f and at least one (m p Time slot interval T sl Here, the time slot interval T sl The duration can be 9 μs. The initial interval includes an idle time slot interval T. sl Furthermore, the number of time slot intervals (m) included in the delay duration can be configured according to the channel access priority, as described above. p In detail, the number of time slot intervals (m) included in the delay duration can be configured as shown in Table 4. p ).

[0199] [Table 4]

[0200]

[0201] Furthermore, wireless communication devices can configure the range of CW values ​​based on channel access priority levels. Specifically, wireless communication devices can configure CW values ​​to meet CW requirements. min,p <=CW<=CW max,p Here, the minimum CW can be determined based on the channel access priority level. min,pand maximum value CW max,p In detail, the minimum value of CW can be determined as shown in Table 4. min,p and maximum value CW max,p Wireless communication devices can configure the minimum value CW during the counter value configuration process. min,p and maximum value CW max,p When a wireless communication device accesses a channel, it can adjust the CW value. Furthermore, the wireless communication device can determine the MCOT(T) in the unlicensed frequency band based on the channel access priority of the data included in the transmission, as described above. mcot,p In detail, the MCOT can be determined as shown in Table 4. Therefore, it may be disallowed for wireless communication devices to continuously transmit in unlicensed frequency bands for periods exceeding the MCOT. This is because unlicensed frequency bands are those used by multiple wireless communication devices according to conventional rules. When the channel access priority level value is p=3 or p=4 in Table 4, and there are no wireless communication devices using unlicensed frequency bands for extended periods according to rules and employing other technologies, the wireless communication device can set T. mcot,p =10ms. Otherwise, the wireless communication device can set T... mcot,p =8ms.

[0202] Figure 14 This is a block diagram illustrating the configuration of user equipment and base station according to an embodiment of the present invention.

[0203] In embodiments of this disclosure, the UE can be implemented using various types of wireless communication devices or computing devices that ensure portability and mobility. The UE can be referred to as User Equipment (UE), Station (STA), Mobile Subscriber (MS), etc. Furthermore, in embodiments of the present invention, the base station controls and manages cells (e.g., macro cells, femtocells, picocells, etc.) corresponding to the service area, and performs functions such as signal transmission, channel designation, channel monitoring, self-diagnosis, and relaying. The base station can be referred to as Next Generation Node B (gNB) or Access Point (AP).

[0204] As shown in the accompanying drawings, the UE 100 according to an embodiment of the present disclosure may include a processor 110, a communication module 120, a memory 130, a user interface 140, and a display unit 150.

[0205] First, the processor 110 can execute various instructions or programs and process data within the UE 100. Additionally, the processor 110 can control the overall operation of each unit including the UE 100 and can control the transmission / reception of data between units. Here, the processor 110 can be configured to perform operations according to the embodiments described herein. For example, the processor 110 can receive time slot configuration information, determine a time slot configuration based on the time slot configuration information, and perform communication according to the determined time slot configuration.

[0206] Next, the communication module 120 can be an integrated module that uses a wireless communication network to perform wireless communication and uses a wireless LAN to perform wireless LAN access. For this purpose, the communication module 120 can include multiple network interface cards (NICs), such as cellular communication interface cards 121 and 122 and an unlicensed band communication interface card 123, either internally or externally. In the accompanying drawings, the communication module 120 is shown as a monolithic integrated module; however, unlike the drawings, each network interface card can be arranged independently depending on the circuit configuration or usage.

[0207] Cellular communication interface card 121 can transmit or receive radio signals with at least one of base station 200, external device, and server using a mobile communication network and provide cellular communication services in a first frequency band based on instructions from processor 110. According to an embodiment, cellular communication interface card 121 may include at least one NIC module using a frequency band less than 6 GHz. At least one NIC module of cellular communication interface card 121 can independently perform cellular communication with at least one of base station 200, external device, and server in accordance with cellular communication standards or protocols in a frequency band below 6 GHz supported by the corresponding NIC module.

[0208] Cellular communication interface card 122 can transmit or receive radio signals with at least one of base station 200, external device, and server using a mobile communication network and provide cellular communication services in a second frequency band based on instructions from processor 110. According to an embodiment, cellular communication interface card 122 may include at least one NIC module using a frequency band greater than 6 GHz. At least one NIC module of cellular communication interface card 122 can independently perform cellular communication with at least one of base station 200, external device, and server in accordance with cellular communication standards or protocols in a frequency band above 6 GHz supported by the corresponding NIC module.

[0209] The unlicensed frequency band communication interface card 123 transmits or receives radio signals with at least one of the base station 200, external devices, and servers by using a third frequency band that is an unlicensed frequency band, and provides unlicensed frequency band communication services based on instructions from the processor 110. The unlicensed frequency band communication interface card 123 may include at least one NIC module using an unlicensed frequency band. For example, the unlicensed frequency band may be a band of 2.4 GHz, 5 GHz, 6 GHz, 7 GHz, or above 52.6 GHz. At least one NIC module of the unlicensed frequency band communication interface card 123 can independently or non-independently perform wireless communication with at least one of the base station 200, external devices, and servers according to the unlicensed frequency band communication standard or protocol supported by the corresponding NIC module.

[0210] The memory 130 stores the control program used in the UE 100 and its various data. Such a control program may include a prescribed program required to perform wireless communication with at least one of the base station 200, external devices, and servers.

[0211] Next, the user interface 140 includes various input / output means configured in the UE 100. In other words, the user interface 140 can use various input means to receive user input, and the processor 110 can control the UE 100 based on the received user input. Furthermore, the user interface 140 can use various output means to execute output based on instructions from the processor 110.

[0212] Next, the display unit 150 outputs various images on the display screen. The display unit 150 can output various display objects, such as content executed by the processor 110 or a user interface, based on control instructions from the processor 110.

[0213] Furthermore, the base station 200 according to an embodiment of the present invention may include a processor 210, a communication module 220, and a memory 230.

[0214] First, the processor 210 can execute various instructions or programs and process the internal data of the base station 200. Furthermore, the processor 210 can control the overall operation of each unit in the base station 200 and control the transmission and reception of data between the units. Here, the processor 210 can be configured to perform operations according to the embodiments described in this invention. For example, the processor 210 can notify time slot configurations with signals and perform communication based on the time slot configurations notified by the used signals.

[0215] Next, the communication module 220 can be an integrated module that uses a wireless communication network to perform wireless communication and uses a wireless LAN to perform wireless LAN access. For this purpose, the communication module 220 can include multiple network interface cards, such as cellular communication interface cards 221 and 222 and an unlicensed frequency band communication interface card 223, either internally or externally. In the accompanying drawings, the communication module 220 is shown as a monolithic integrated module; however, unlike the drawings, each network interface card can be arranged independently depending on the circuit configuration or usage.

[0216] Cellular communication interface card 221 can transmit or receive radio signals with at least one of UE 100, external device, and server using a mobile communication network and provide cellular communication services in a first frequency band based on instructions from processor 210. According to an embodiment, cellular communication interface card 221 may include at least one NIC module using a frequency band less than 6 GHz. At least one NIC module of cellular communication interface card 221 can independently perform cellular communication with at least one of UE 100, external device, and server in accordance with cellular communication standards or protocols in a frequency band less than 6 GHz supported by the corresponding NIC module.

[0217] Cellular communication interface card 222 can transmit or receive radio signals with at least one of UE 100, external devices, and servers using a mobile communication network and provide cellular communication services in a second frequency band based on instructions from processor 210. According to an embodiment, cellular communication interface card 222 may include at least one NIC module using a 6 GHz or higher frequency band. At least one NIC module of cellular communication interface card 222 can independently perform cellular communication with at least one of UE 100, external devices, and servers in accordance with cellular communication standards or protocols in a 6 GHz or higher frequency band supported by the corresponding NIC module.

[0218] The unlicensed frequency band communication interface card 223 transmits or receives radio signals with at least one of the UE 100, external devices, and servers by using a third frequency band that is an unlicensed frequency band, and provides unlicensed frequency band communication services based on instructions from the processor 210. The unlicensed frequency band communication interface card 223 may include at least one NIC module using an unlicensed frequency band. For example, the unlicensed frequency band may be a band of 2.4 GHz, 5 GHz, 6 GHz, 7 GHz, or above 52.6 GHz. At least one NIC module of the unlicensed frequency band communication interface card 223 can independently or dependently perform wireless communication with at least one of the UE 100, external devices, and servers in accordance with the unlicensed frequency band communication standards or protocols supported by the corresponding NIC module.

[0219] Figure 14This is a block diagram illustrating a UE 100 and a base station 200 according to an embodiment of the present invention, and the blocks shown individually are logically divided elements of the device. Therefore, the aforementioned elements of the device can be installed in a single chip or multiple chips depending on the device design. Furthermore, a portion of the configuration of the UE 100, such as a user interface 140, a display unit 150, etc., may be selectively provided in the UE 100. Additionally, the user interface 140, display unit 150, etc., may be additionally provided in the base station 200 if necessary.

[0220] Figure 15 This is a diagram illustrating the downlink channel access process according to an embodiment of the present invention.

[0221] Figure 15 This is a diagram illustrating the downlink channel access process used during UE-initiated Channel Occupancy Time (COT) sharing. Figure 15 (a) illustrates an example of the downlink channel access process when the gap is less than 16 μs. Figure 15 Figure (b) illustrates an example of the downlink channel access procedure when the gap is 16 μs, and Figure 15 (c) shows an example of the downlink channel access process when the gap is 25 μs.

[0222] To perform uplink (e.g., PUSCH) transmissions on scheduled or configured resources, a user equipment (UE) can use a Category 4 channel access procedure to obtain a channel occupancy initiated by the UE. Furthermore, the UE can share a channel occupancy with the base station for base station transmissions.

[0223] When information about the energy detection (ED) threshold is configured

[0224] User equipment (UE) can receive from the base station the threshold for ED applied when acquiring channel occupancy. For example, the base station can configure the ED threshold by sending the RRC parameter 'ULtoDL-CO-SharingED-Threshold-r16' as the threshold for ED to the UE. When the UE shares channel occupancy with the base station, the base station can transmit a specific channel or a specific signal. Here, uplink transmission can be a configuration grant (CG)-PUSCH or a scheduled uplink (e.g., a scheduled grant PUSCH) transmission. After the UE's uplink transmission, the base station's downlink transmission can be performed. In this specification, a CG uplink transmission (e.g., CG-PUSCH) can be an uplink transmission (e.g., CG-PUSCH) in which the base station pre-semi-statically configures resources for uplink transmission for the UE and is performed by the UE on the pre-configured resources.

[0225] When the uplink transmission performed by the user equipment (UE) is CG-PUSCH, the UE can receive a table from the base station for sharing channel occupancy. Specifically, the UE can receive from the base station a configuration for sharing channel occupancy-related information (e.g., Channel Occupancy Time (COT)) between the base station and the UE via the RRC parameter 'COT-SharingList-r16'. Furthermore, the UE can receive channel occupancy information corresponding to each row of the table from the base station. For example, channel occupancy information corresponding to each row of the table can be provided via the RRC parameter 'cg-COT-Sharing-r16'. Here, one row of the table can be configured to indicate that channel occupancy is not shared. When the UE shares channel occupancy with the base station for CG-PUSCH initiated by the UE, the UE can indicate the index (row index) corresponding to a row of the table configured from the base station via the COT sharing information included in the CG-Uplink Control Information (UCI) of the CG-PUSCH. In other words, when a user equipment (UE) indicates an index corresponding to a row in a table providing channel occupancy information, the base station can perform downlink transmissions by assuming one or more values ​​corresponding to the channel occupancy information indicated by the row in the table indicated by the index. Specifically, channel occupancy information may include duration, offset, CAPC, etc. Duration may represent the number of time slots available (assumable) in downlink transmissions within the time period of channel occupancy initiated by the UE. Offset represents the time interval (difference) from the end of the time slot in which the base station has detected CG-UCI to the time slot in which downlink transmissions begin to be performed by the base station. CAPC represents the assumed CAPC when the UE and the base station share the channel occupancy initiated by the UE.

[0226] When information about the energy detection (ED) threshold is not configured

[0227] It is possible that the base station has not configured the ED threshold for the user equipment. In other words, it is possible that the user equipment cannot receive the ED threshold from the base station. That is, the base station may not have configured 'ULtoDL-CO-SharingED-Threshold-r16' as the RRC parameter for the ED threshold, and may not have configured the ED threshold for the user equipment. Here, when the uplink transmission performed by the user equipment is CG-PUSCH, the CG-UCI of CG-PUSCH may include 'COT sharing information' indicating whether channel occupancy is shared. When the user equipment indicates that channel occupancy is shared through CG-UCI (e.g., when the value of COT sharing information is 1), the user equipment may allow X symbols configured from the base station for the downlink transmission performed by the base station. Specifically, the user equipment may receive the RRC parameter 'cg-COT-SharingOffset-r16' indicating X symbols for downlink transmission from the base station, and the base station may allow X symbols for shared channel occupancy for downlink transmission. Here, X symbols represent the X symbols starting from the end of time slot n (time slot #n) in which the base station has detected CG-UCI.

[0228] Here, downlink transmission of the base station can be performed after uplink transmission of the user equipment. The length of the downlink transmission can be limited to a maximum of 2 symbols, 4 symbols, or 8 symbols depending on the subcarrier spacing. Downlink transmission can be limited to a maximum of 2 symbols when the subcarrier spacing is 15 kHz, a maximum of 4 symbols when the subcarrier spacing is 30 kHz, and a maximum of 8 symbols when the subcarrier spacing is 60 kHz.

[0229] The following will describe the downlink transmission performed by the base station after the uplink transmission of the user equipment. Here, the downlink transmission performed by the base station can correspond to both the case in which the base station has sent (configured) RRC parameters for the threshold of ED to the user equipment and the case in which the base station has not sent (configured) RRC parameters for the threshold of ED.

[0230] i) When the base station has configured the ED threshold by configuring 'ULtoDL-CO-SharingED-Threshold-r16' as the RRC parameter for the user equipment (UE) as the threshold for ED, the base station can perform downlink transmission including DRS only after the UE performs uplink (e.g., PUSCH) transmission on scheduled or configured resources. In this specification, the DRS may include at least one SSB, which includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a physical broadcast channel (PBCH), and a DR-RS for the PBCH. Furthermore, the DRS may include a PDSCH for carrying System Information Block 1 (SIB1) and a CORESET for scheduling the PDCCH. Additionally, the DRS may include a non-zero power CSI reference signal.

[0231] Meanwhile, when the ED threshold has not been configured because the base station has not configured the RRC parameter 'ULtoDL-CO-SharingED-Threshold-r16' as the threshold for ED for the user equipment, downlink transmission including only DRS can only be performed when the subcarrier spacing is at least 30kHz. This is because the number of symbols occupied by the SSB included in the DRS is at least 4.

[0232] ii) The base station can perform downlink transmissions, including DRS, after the user equipment performs uplink (e.g., PUSCH) transmissions on scheduled or configured resources. Here, in the base station's downlink transmissions, any user equipment's non-unicast transmissions can be multiplexed.

[0233] iii) The base station may perform downlink transmissions after the user equipment performs uplink (e.g., PUSCH) transmissions on scheduled or configured resources. Here, the downlink transmissions performed by the base station may include reference signals (e.g., CSI-RS, tracking RS, etc.) for user equipment that has initiated channel occupancy and non-unicast transmissions for any user equipment.

[0234] iv) The base station may perform downlink transmissions after the user equipment performs uplink (e.g., PUSCH) transmissions on scheduled or configured resources. Here, the downlink transmissions performed by the base station may not include user plane data for user equipment that has initiated channel occupancy, but may include unicast transmissions containing control plane data (e.g., data for RRC configuration) and non-unicast transmissions for any user equipment.

[0235] When a channel occupancy initiated by a user equipment (UE) is shared with a base station, the base station can perform channel access and downlink transmissions (i) to iv) above, based on a specific gap or a gap smaller than that specific gap, after the uplink transmission performed by the UE. The base station's channel access procedure will be described below.

[0236] When the gap is less than 16 μs, the base station can perform downlink transmission after performing a Type 2C downlink channel access procedure. The Type 2C downlink channel access procedure instructs the base station to perform downlink transmission without performing channel sensing prior to downlink transmission. The duration for downlink transmission can be limited to a maximum of 584 μs (refer to 3GPP TS37.213).

[0237]

[0238] When the gap is 16 μs, the base station can perform downlink transmission after performing a Type 2B downlink channel access procedure. The Type 2B downlink channel access procedure instructs the base station to perform downlink transmission immediately after sensing whether the channel is idle for a duration of 16 μs (T_f), prior to performing downlink transmission. 16 μs (T_f) may include a sensing time slot within the last 9 μs of the 16 μs. A channel can be considered idle when it is sensed to be idle for the entire interval (e.g., at least 5 μs) including the interval in which sensing is performed (e.g., at least 4 μs) within the sensing time slot (see 3GPP TS 37.213).

[0239]

[0240] When the gap is 25 μs, the base station can perform downlink transmission after performing a Type 2A downlink channel access procedure. The Type 2A downlink channel access procedure instructs the base station to perform downlink transmission immediately after sensing whether the channel is idle during a 25 μs (T_short_dl) sensing interval, before performing downlink transmission. The (T_short_dl) sensing interval can be configured with a 16 μs (T_f) interval and a sensing slot (9 μs) immediately following this 16 μs (T_f) interval. The 16 μs (T_f) interval can include a sensing slot (9 μs). When the 25 μs (T_short_dl) sensing interval (i.e., the entire sensing slot) is sensed as idle, the channel can be considered idle during the 25 μs (T_short_dl) interval (see 3GPP TS37.213).

[0241]

[0242] Figure 16This is a diagram illustrating the scheduling of uplink transmission according to an embodiment of the present invention.

[0243] In detail, Figure 16 The illustration shows a user equipment performing a scheduled uplink transmission when it is scheduled from the base station to perform uplink transmissions without gaps after resources are configured for autonomous transmission or CG-PUSCH.

[0244] When a user equipment is configured to perform scheduled uplink transmissions, the user equipment may perform scheduled uplink transmissions without performing channel access if the following conditions are met: Uplink transmissions on resources configured for autonomous transmission or CG-PUSCH may be dropped at the last symbol of a time slot (e.g., time slot (n-1)) preceding the start time of the time slot used for scheduled uplink transmissions (e.g., time slot n).

[0245] The conditions for user equipment to perform scheduled uplink transmissions without performing channel access will be described below.

[0246] a) User equipment (UE) shall perform Category 4 channel access (e.g., Category 1 uplink channel access) to perform uplink transmissions on resources configured for autonomous transmissions or CG-PUSCH. Furthermore, UE shall perform uplink transmissions on resources configured for autonomous transmissions or CG-PUSCH prior to the start time of the scheduled uplink transmission.

[0247] (b) For frequency-domain resources used for scheduled uplink transmissions, all resource blocks (RBs) of the LBT bandwidth (e.g., 20 MHz) occupied by the time slot that may be scheduled first in the time-domain resources configured for the scheduled uplink transmissions should be scheduled. Alternatively, all RBs of the uplink bandwidth portion (BWP) configured for the user equipment should be scheduled. Here, the starting symbol index of the time slot that is scheduled first in the time-domain resources configured for CG-PUSCH can be 0. Alternatively, multiple LBT bandwidths can exist within a BWP. Here, resources for autonomous transmissions or resources configured for CG-PUSCH are allocated to at least one LBT bandwidth within a BWP, and the frequency-domain resources used for scheduled uplink transmissions can occupy all RBs of a subset of at least one LBT bandwidth or all RBs of all LBT bandwidths including resources for autonomous transmissions or resources configured for CG-PUSCH.

[0248] c) When a user equipment performs Category 4 channel access (e.g., Type 1 uplink channel access) to perform uplink transmission on resources configured for autonomous transmission or CG-PUSCH, the CAPC used should be greater than or equal to the CAPC indicated by the base station for scheduling the uplink transmission.

[0249] d) The sum of the length of the uplink transmission on the resources configured for autonomous transmission or CG-PUSCH and the length of the scheduled uplink transmission should not exceed the maximum channel occupancy time (MCOT). Here, MCOT is the MCOT configured when the user equipment performs Category 4 channel access (e.g., Type 1 uplink channel access) to perform uplink transmission on the resources configured for autonomous transmission or CG-PUSCH.

[0250] If none of the conditions a) through d) are met, uplink transmissions on resources configured for autonomous transmission or CG-PUSCH may be dropped at the last symbol of a time slot (e.g., time slot (n-1)) preceding the start time of the time slot used for scheduling uplink transmissions (e.g., time slot n). Alternatively, the user equipment may drop uplink transmissions on resources configured for autonomous transmission or CG-PUSCH at a number of time slots (e.g., time slot (n-1)) preceding the start time of the time slot used for scheduling uplink transmissions (e.g., time slot n) and at least one time slot. Meanwhile, if the time allowed for dropping uplink transmissions (cancellation guarantee time) has not yet elapsed, the user equipment may drop uplink transmissions on resources configured for autonomous transmission or CG-PUSCH at a number of time slots (e.g., time slot (n-1)) preceding the start time of the time slot used for scheduling uplink transmissions (e.g., time slot n) and at least one time slot. However, once the time allowed for discarding uplink transmissions has elapsed, the user equipment (UE) can perform the scheduled uplink transmission in the next time slot (e.g., the (n+1)th time slot) after the start time of the time slot used for the scheduled uplink transmission (e.g., the nth time slot). Here, in the channel access process for performing the scheduled uplink transmission in the next time slot (e.g., the (n+1)th time slot), Category 4 channel access (e.g., Type 1 uplink channel access) can be used. Alternatively, when the resources used for the scheduled uplink transmission are included in the MCOT configured when the UE performs Category 4 channel access (e.g., Type 1 uplink channel access) for uplink transmission on resources configured for autonomous transmission or CG-PUSCH, the UE can perform the scheduled uplink transmission based on Category 2 channel access (e.g., Type 2A uplink channel access).

[0251] When a user equipment (UE) has been scheduled from a base station to perform uplink transmissions continuously and without gaps after resources have been configured for autonomous transmissions or CG-PUSCH, the UE can perform scheduled uplink transmissions even without channel access, depending on the type of scheduled uplink transmission. The type of scheduled uplink transmission can include a PUSCH containing an uplink shared channel (UL-SCH), a PUSCH without an UL-SCH, a PUCCH for transmitting uplink control information, uplink transmissions related to random access procedures (e.g., PRACH preamble, Msg3), sounding reference signals (SRS), etc. Here, the PUCCH can include HARQ-ACK, scheduling request (SR), beam fault recovery request (BFR), or channel state information (CSI).

[0252] When conditions a) to d) are met, the user equipment can perform scheduled uplink transmissions without performing channel access (e.g., LBT) regardless of the type of scheduled uplink transmission.

[0253] When the scheduled uplink transmission is an uplink transmission excluding PUSCH and satisfies the above conditions a), c), and d), the user equipment can perform the scheduled uplink transmission without performing channel access.

[0254] When the scheduled uplink transmission is an uplink transmission excluding the PUSCH including UL-SCH and satisfies the above conditions a), c), and d), the user equipment can perform the scheduled uplink transmission without performing channel access.

[0255] The scheduled uplink transmission can be a PUCCH including at least one of HARQ-ACK, SR, or BFR. Here, when the PUCCH transmission has been scheduled by extending the LBT bandwidth through interleaved PUCCH transmission configured for PUCCH transmission using RRC, the user equipment can perform the scheduled PUCCH transmission without performing channel access if the above conditions a), c), and d) are met. This is to ensure transmission on the scheduled resources as much as possible, because in the case of a PUCCH including at least one of HARQ-ACK, SR, or BFR, the latency due to link failure may increase significantly, or the data transmission rate of the uplink / downlink transmission may decrease due to failure during the channel access process. In addition, the CAPC used for PUCCH transmission can generally be set to 1. Therefore, the CAPC used for PUCCH transmission can always be less than or equal to the CAPC used by the user equipment when performing Category 4 channel access (e.g., Type 1 uplink channel access) to perform uplink transmission on resources configured for autonomous transmission or CG-PUSCH, thus satisfying the above condition c).

[0256] When the scheduled uplink transmissions are SRS, PUCCH excluding PUSCH, PUSCH excluding UL-SCH, and transmissions related to random access procedures (e.g., PRACH preamble, Msg3), if conditions a), c), and d) are met, the user equipment can perform the scheduled uplink transmissions without performing a channel access procedure. Here, for SRS, PUCCH excluding PUSCH, PUSCH excluding UL-SCH, and transmissions related to random access procedures (e.g., PRACH preamble, Msg3), a Category 4 channel access procedure (e.g., Type 1 uplink channel access) can be performed, and in this case, CAPC can be set to 1.

[0257] Figure 17 This is a flowchart illustrating a method for a user equipment to receive downlink transmissions according to an embodiment of the present invention.

[0258] Reference Figure 17 Describes a method for a user equipment to receive downlink transmissions.

[0259] The user equipment performs uplink transmissions to the base station related to the channel occupancy shared between the base station and the user equipment (S1710).

[0260] The user equipment receives the downlink transmission performed by the base station after the gap from the reception time of the uplink transmission (S1720).

[0261] Downlink transmission can be performed based on channel access performed by the base station, where channel access can be performed based on gaps.

[0262] The information to be included in the downlink transmission and the resources to perform the downlink transmission can be determined based on whether the user equipment has received the energy detection threshold from the base station.

[0263] Here, the gap can be less than 16 μs, 16 μs, or 25 μs. When the gap is less than 16 μs, the channel access can be a channel access that allows downlink transmission without performing channel sensing, i.e., type 2C downlink channel access described above. When the gap is 16 μs, the gap includes a sensing time slot within the last 9 μs, and the channel access can be a channel access that allows downlink transmission when the sensing time slot is idle, i.e., type 2B downlink channel access described above. When the gap is 25 μs, the gap is configured with a first interval of 16 μs, including a first sensing time slot of 9 μs and a second interval of 9 μs, and the channel access can be a channel access that allows downlink transmission when the first and second sensing time slots are idle, i.e., type 2A downlink channel access described above. When the user equipment has received the configuration of the energy detection threshold for channel occupancy from the base station, the information included in the downlink transmission can include at least one of unicast transmission for the user equipment that has initiated channel occupancy or non-unicast transmission for any user equipment. Meanwhile, when the user equipment has not yet received the configuration of the energy detection threshold for channel occupancy from the base station, information included in downlink transmission excludes unicast transmission, and the maximum number of symbols for resources performing downlink transmission within the channel occupancy interval can be any one of 2, 4, and 8. When the subcarrier spacing (SCS) is 15 kHz, the resources for performing downlink transmission within the channel occupancy interval can include a maximum of two symbols. When the SCS is 30 kHz, the resources for performing downlink transmission within the channel occupancy interval can include a maximum of four symbols. When the SCS is 60 kHz, the resources for performing downlink transmission within the channel occupancy interval can include a maximum of eight symbols.

[0264] Uplink transmissions performed by a user equipment (UE) can be configured permission (CG) - Physical Uplink Shared Channel (PUSCH) performed on resources semi-statically pre-configured from a base station. Here, when the UE has received configuration from the base station for an energy detection threshold for channel occupancy, the UE can receive configuration from the base station for a table containing a value set for each of one or more parameters for channel occupancy and one or more indices corresponding to the set values. The CG-PUSCH may include CG-Uplink Control Information (UCI), which includes information indicating a first index among the one or more indices. Downlink transmissions can be performed based on values ​​set for each of the one or more parameters corresponding to the first index. The one or more parameters may be at least one of Channel Access Priority (CAPC), duration, or offset. CAPC may be the CAPC used in a channel occupancy initiated by the UE, the duration may represent the number of time slots available (assumed) for downlink transmission within the time of the channel occupancy initiated by the UE, and the offset may represent the difference from the end of the time slot in which the base station has detected CG-UCI to the time slot in which downlink transmission begins. Simultaneously, when the user equipment (UE) does not receive the configuration for the energy detection threshold for channel occupancy from the base station, the UE can receive from the base station an offset (symbol) indicating the resources (symbols) available for downlink transmission (permitted for downlink transmission). The CG-PUSCH may include a CG-UCI containing information indicating that channel occupancy is possible, and downlink transmission can be performed on the resources between the last resource in the time slot where the base station has detected the CG-UCI and resources spaced apart and offset by the same amount. Here, the information included in the downlink transmission excludes unicast transmission, and the maximum number of symbols for resources used for downlink transmission within the channel occupancy interval can be any one of 2, 4, and 8. When the subcarrier spacing (SCS) is 15 kHz, the resources used for downlink transmission within the channel occupancy interval may include a maximum of two symbols. When the SCS is 30 kHz, the resources used for downlink transmission within the channel occupancy interval may include a maximum of four symbols. When the SCS is 60 kHz, the resources used for downlink transmission within the channel occupancy interval may include a maximum of eight symbols.

[0265] Execution Reference Figure 17 The user equipment described in the method for receiving downlink transmissions sent from a base station can be the one referenced above. Figure 14 The user equipment described. Specifically, the user equipment may include a communication module for transmitting / receiving wireless signals and a processor for controlling the communication module. Here, reference is made to... Figure 17 The method described for receiving downlink transmissions can be executed by a processor. Similarly, the base station can be the one described above. Figure 14 The base station described. The base station may also include a communication module for transmitting / receiving wireless signals and a processor for controlling the communication module.

[0266] Figure 18 This is a flowchart illustrating a method for a user equipment to perform uplink transmission according to an embodiment of the present invention.

[0267] Reference Figure 18 This describes a method for performing uplink transmissions on the aforementioned user equipment.

[0268] The user equipment performs a first transmission (S1810) on the first resource to the base station as a configuration license (CG) uplink transmission.

[0269] Here, CG uplink transmission can be a transmission performed on resources that are semi-statically pre-configured from the base station.

[0270] The user equipment performs a second transmission (S1820) on the second resource to the base station as a scheduled uplink transmission.

[0271] The first and second resources can be consecutive to each other in the time domain.

[0272] A second transfer can be performed on a second resource immediately following the last symbol of the first resource when at least one pre-configuration condition is met.

[0273] If at least one pre-configured condition is not met, the first transmission may be dropped at the last symbol of the first resource.

[0274] At least one of the pre-configured conditions may be the condition for performing the first transmission based on channel access in which a variable-sized contention window (CW) is used to perform random backoff, i.e., the category 4 channel access described above.

[0275] At least one of the pre-configuration conditions may be the condition that the resources allocated for the second transmission occupy all resource blocks (RBs) in the same frequency domain as the resources allocated for the first transmission.

[0276] One of the at least one pre-configuration conditions may be that when the bandwidth portion (BWP) of the resources allocated for the first transmission in the frequency domain is configured with multiple listen-before-talk (LBT) bandwidth subsets, the resource occupancy allocated for the second transmission includes all resource blocks (RBs) in at least one of the multiple LBT bandwidth subsets.

[0277] At least one of the pre-configuration conditions may be a condition for performing the second transmission based on a second CAPC value that is less than or equal to the first channel access priority level (CAPC) value used in channel access.

[0278] At least one of the pre-configuration conditions may be that the sum of the time domain of the first resource and the time domain of the second resource does not exceed the maximum channel occupancy time (MCOT) corresponding to the first CAPC value.

[0279] Execution Reference Figure 18 The user equipment described for uplink transmission can be the one mentioned above. Figure 14 The user equipment described. Specifically, the user equipment may include a communication module for transmitting / receiving wireless signals and a processor for controlling the communication module. Here, reference is made to... Figure 18 The method described for receiving downlink transmissions can be executed by a processor. Similarly, the base station can be the one described above. Figure 14 The base station described. The base station may also include a communication module for transmitting / receiving wireless signals and a processor for controlling the communication module.

[0280] The methods and systems of the present invention are described with reference to specific embodiments, but some or all of the components or operations can be implemented using a computer system with a general hardware architecture.

[0281] The above description of the present invention is merely illustrative, and it will be readily understood that those skilled in the art can easily make modifications without departing from the technical concept of the invention or changing the essential features. Therefore, the above embodiments should be considered illustrative and not construed as restrictive. For example, each component described as a single type may be distributed, and similarly, components described as distributed may be implemented in a composite form.

[0282] The scope of this invention is indicated by the following claims rather than a detailed description, and it should be understood that all variations or modifications derived from the meaning and scope of the claims and their equivalents are included within the scope of this invention.

Claims

1. A method used by a user equipment in a wireless communication system, the method comprising: The first transport is performed on the first resource as part of the configuration-permitted CG uplink transport. The CG uplink transmission is performed on semi-statically pre-configured resources; The first resource is configured with multiple listen-before-speak LBT bandwidths; and The second transmission, which is scheduled as an uplink transmission, is performed on the second resource. When the condition is met, the second transfer is performed on the second resource immediately following the last symbol of the first resource, and If the condition is not met, the first transmission is discarded before the start symbol of the second resource. One of the conditions is: The second resource occupancy includes all resource blocks (RBs) in a subset of the plurality of LBT bandwidths.

2. The method according to claim 1, wherein, One of the conditions is based on channel access in which random backoff is performed using a contention window (CW) of variable size, and the first transmission is performed.

3. The method according to claim 2, wherein, One of the conditions is to execute the second transmission based on a second CAPC value corresponding to the scheduled uplink transmission that is less than or equal to the first channel access priority level CAPC value used in the channel access.

4. The method according to claim 3, wherein, One of the conditions is that the sum of the time domain of the first resource and the time domain of the second resource does not exceed the maximum channel occupancy time (MCOT) corresponding to the first CAPC value.

5. A user equipment configured to operate in a wireless communication system, the user equipment comprising: Communication module; as well as The processor controls the communication module. The processor is configured as follows: The first transport is performed on the first resource as part of the configuration-permitted CG uplink transport. The CG uplink transmission is performed on semi-statically pre-configured resources. The first resource is configured with multiple LBT (Listen Before You Speak) bandwidths. The second transmission, which is scheduled as an uplink transmission, is performed on the second resource. When the condition is met, the second transfer is performed on the second resource immediately following the last symbol of the first resource, and If the condition is not met, the first transmission is discarded before the start symbol of the second resource. One of the conditions is: The second resource occupancy includes all resource blocks (RBs) in a subset of the plurality of LBT bandwidths.

6. The user equipment according to claim 5, wherein, One of the conditions is based on channel access in which random backoff is performed using a contention window (CW) of variable size, and the first transmission is performed.

7. The user equipment according to claim 6, wherein, One of the conditions is to execute the second transmission based on a second CAPC value corresponding to the scheduled uplink transmission that is less than or equal to the first channel access priority level CAPC value used in the channel access.

8. The user equipment according to claim 7, wherein, One of the conditions is that the sum of the time domain of the first resource and the time domain of the second resource does not exceed the maximum channel occupancy time (MCOT) corresponding to the first CAPC value.

Images