Method and apparatus for transmitting / receiving a signal using variable bandwidth in a communication system

Abstract

A method and apparatus for transmitting / receiving signals in a communication system using variable bandwidth are disclosed. A terminal operation method includes the following steps: receiving first configuration information of one or more guard bands in an unlicensed band from a base station; confirming the one or more guard bands configured in the unlicensed band based on the first configuration information; and confirming a plurality of RB sets configured in the unlicensed band based on the one or more guard bands. This can improve the performance of the communication system.

Description

Technical Field

[0001] This invention relates to techniques for transmitting and receiving signals and / or channels in a communication system, and more specifically, to techniques for transmitting and receiving signals and / or channels in a communication system by using variable bandwidth. Background Technology

[0002] With the development of information and communication technologies, various wireless communication technologies have emerged. Communication systems using frequency bands higher than Long Term Evolution (LTE) (or LTE-A) (e.g., 6 GHz or lower) (hereinafter referred to as New Radio (NR) communication systems) are being considered for handling surging wireless data. NR communication systems can support not only frequency bands below 6 GHz but also bands of 6 GHz or higher, and can support a wider range of communication services and scenarios compared to LTE communication systems. For example, use cases for NR communication systems can include Enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency Communication (URLLC), and Massive Machine-Type Communication (mMTC). Communication technologies are needed to meet the requirements of eMBB, URLLC, and mMTC.

[0003] In NR communication systems, communication nodes (e.g., base stations and terminals) can use fixed bandwidth to transmit and receive signals and / or channels. Depending on the channel environment between the communication nodes, variable bandwidth is required instead of fixed bandwidth. In this case, the base station should be able to transmit signals and / or channels after variably adjusting the bandwidth, and the terminal should be able to successfully receive the signals and / or channels using the variable bandwidth. Therefore, a method for efficiently transmitting and receiving signals and / or channels using variable bandwidth is needed.

[0004] Furthermore, the above-described techniques are intended to enhance understanding of the background of this disclosure, and the above-described techniques may include non-prior techniques not yet known to those skilled in the art. Summary of the Invention

[0005] [Technical Issues]

[0006] The present invention aims to provide a method and apparatus for transmitting and receiving signals and / or channels using variable bandwidth in a communication system.

[0007] [Technical Solution]

[0008] An operational method for a terminal to achieve the above-described objective according to a first exemplary embodiment of the present invention may include: receiving first configuration information of one or more guard bands of an unlicensed band from a base station; identifying the one or more guard bands configured in the unlicensed band based on the first configuration information; and identifying a plurality of resource block (RB) sets configured in the unlicensed band based on the one or more guard bands, wherein each of the one or more guard bands is located between two adjacent RB sets.

[0009] The first configuration information may include the start protection RB (G-RB) index and the end G-RB index of each of the one or more protection strips, and when N protection strips are configured, the number of pairs of the start G-RB index and the end G-RB index included in the first configuration information may be N, where N is an integer greater than or equal to 1.

[0010] The number of multiple RB sets configured within the bandwidth portion (BWP) of the unlicensed band can be N+1.

[0011] The number of RBs included in each of the multiple RB sets can be the number of RBs located between adjacent protection zones.

[0012] The starting RB set in the plurality of RB sets may include the starting RB of the unlicensed band up to the RB immediately preceding the starting G-RB of the starting protection band in the one or more protection bands, and the ending RB set in the plurality of RB sets may include the RB after the ending G-RB of the ending protection band in the one or more protection bands up to the ending RB of the unlicensed band; and the starting RB set may be the RB set with the lowest frequency resource in the plurality of RB sets, while the ending RB set may be the RB set with the highest frequency resource in the plurality of RB sets, the starting protection band may be the protection band with the lowest frequency resource in the one or more protection bands, and the ending protection band may be the protection band with the highest frequency resource in the one or more protection bands.

[0013] The operation method may further include receiving second configuration information from the base station indicating whether to perform downlink communication in each of the plurality of RB sets.

[0014] The second configuration information may be a bitmap, and the bitmap may be included in downlink control information (DCI).

[0015] The resources of the Channel State Information Reference Signal (CSI-RS) can be configured in multiple RB sets, and measurement operations can be omitted from the CSI-RS when no downlink communication is performed in one or more of the multiple RB sets.

[0016] An operating method for a base station to achieve the above-described objective according to a second exemplary embodiment of the present invention may include: configuring one or more guard bands of an unlicensed band; sending first configuration information of the one or more guard bands to a terminal; and communicating with the terminal by using one or more resource block (RB) sets of a plurality of resource blocks (RBs) configured in frequency resources other than the one or more guard bands in the unlicensed band, wherein the number, location, and size of the plurality of RB sets are determined based on the first configuration information.

[0017] The first configuration information may include the start protection RB (G-RB) index and the end G-RB index of each of the one or more protection bands, and when N protection bands are configured, the number of pairs of start G-RB indices and end G-RB indices included in the first configuration information may be N, where N may be an integer equal to or greater than 1.

[0018] The number of multiple RB sets configured within the bandwidth portion (BWP) of the unlicensed band can be N+1, and the number of RBs included in each of the multiple RB sets can be the number of RBs located between adjacent guard bands.

[0019] The operation method may further include sending second configuration information to the terminal indicating whether to perform downlink communication in a plurality of RB sets, wherein the second configuration information may be a bitmap and the bitmap may be included in downlink control information (DCI).

[0020] The resources for Channel State Information Reference Signal (CSI-RS) can be configured in multiple RB sets, and when no downlink communication is performed in one or more of the multiple RB sets, the measurement results of CSI-RS may not be received from the terminal.

[0021] The operation method may further include sending to the terminal a third configuration information of a control resource set (CORESET) configured in the unlicensed band and a fourth configuration information of a search space configured in the unlicensed band, wherein the third configuration information may be applied to multiple RB sets, and the number of RBs with CORESET set configured may be equal to or less than the number of RBs belonging to an RB set.

[0022] The third configuration information may include an offset indicating the position of the CORESET on the frequency axis, and the offset may indicate the deviation between the starting RB of the unlicensed band and the starting RB of the CORESET.

[0023] The search space associated with CORESET can be repeated across multiple RB sets, and the fourth configuration information may include a field indicating whether the search space is configured in each of the multiple RB sets.

[0024] A terminal according to a third exemplary embodiment of the invention for achieving the above objectives may include a processor and a memory storing at least one instruction executable by the processor, wherein the at least one instruction causes the processor to: receive first configuration information of one or more guard bands in an unlicensed band from a base station; identify the one or more guard bands configured in the unlicensed band based on the first configuration information; identify a plurality of resource block (RB) sets configured in the unlicensed band based on the one or more guard bands; and receive second configuration information of a control resource set (CORESET) configured in the unlicensed band and third configuration information of a search space configured in the unlicensed band from the base station, wherein the second configuration information is jointly applied to the plurality of RB sets, and wherein the number of RBs with CORESET set set is equal to or less than the number of RBs belonging to one RB set.

[0025] The first configuration information may include the start protection RB (G-RB) index and the end G-RB index of each of the one or more protection bands; when N protection bands are configured, the number of pairs of the start G-RB index and the end G-RB index included in the first configuration information may be N; the number of multiple RB sets configured in the bandwidth portion (BWP) of the unlicensed band may be N+1; and N may be an integer greater than or equal to 1.

[0026] The second configuration information may include an offset indicating the position of the CORESET on the frequency axis, and the offset may indicate the deviation between the starting RB of the unlicensed band and the starting RB of the CORESET.

[0027] The search space associated with CORESET can be repeated in the plurality of RB sets, and the third configuration information may include a field indicating whether the search space is configured in each of the plurality of RB sets.

[0028] [Beneficial Effects]

[0029] According to the present invention, a base station may send configuration information of one or more guard bands configured within the bandwidth portion (BWP) of an unlicensed band to a terminal. The terminal may identify one or more guard bands configured within the BWP based on the configuration information received from the base station, and may estimate the number, location, and size of the resource block (RB) set configured within the BWP based on the one or more guard bands.

[0030] Additionally, the base station can send configuration information of the search space and control resource set (CORESET) configured within the BWP to the terminal. The terminal can identify the CORESET and search space configured within the BWP based on the configuration information received from the base station. Furthermore, the base station can send configuration information to the terminal indicating one or more RB sets within the configured RB sets used for downlink communication. The terminal can identify one or more RB sets used for downlink communication based on the configuration information received from the base station.

[0031] In the unlicensed band, communication between the base station and the terminal can be performed using one or more RB sets, CORESET, and search space configured by the base station. Therefore, variable bandwidth can be used for communication between the base station and the terminal, and the performance of the communication system can be improved. Attached Figure Description

[0032] Figure 1 This is a conceptual diagram illustrating a first exemplary embodiment of the communication system.

[0033] Figure 2 This is a block diagram illustrating a first exemplary embodiment of a communication node constituting a communication system.

[0034] Figure 3 This is a conceptual diagram illustrating a first exemplary embodiment of a system frame in a communication system.

[0035] Figure 4 This is a conceptual diagram illustrating a first exemplary embodiment of a subframe in a communication system.

[0036] Figure 5 This is a conceptual diagram illustrating a first exemplary embodiment of a time slot in a communication system.

[0037] Figure 6 This is a conceptual diagram illustrating a second exemplary embodiment of a time slot in a communication system.

[0038] Figure 7 This is a conceptual diagram of a first exemplary embodiment of time-frequency resources in a communication system.

[0039] Figure 8 This is a conceptual diagram of a third exemplary embodiment of a time slot in a communication system.

[0040] Figure 9 This is a conceptual diagram illustrating a fourth exemplary embodiment of a time slot in a communication system.

[0041] Figure 10 This is a conceptual diagram of a first exemplary embodiment of a PDCCH monitoring method in a communication system.

[0042] Figure 11 This is a conceptual diagram of a first exemplary embodiment of an LBT subband in a communication system.

[0043] Figure 12 This is a conceptual diagram illustrating a first exemplary embodiment of a communication method using LBT subbands in a communication system.

[0044] Figure 13 This is a conceptual diagram illustrating a second exemplary embodiment of a communication method using LBT subbands in a communication system.

[0045] Figure 14 This is a conceptual diagram illustrating a third exemplary embodiment of a communication method using LBT subbands in a communication system.

[0046] Figure 15 This is a conceptual diagram illustrating a fourth exemplary embodiment of a communication method using LBT subbands in a communication system. Detailed Implementation

[0047] Although the invention is readily subject to various modifications and substitutions, specific embodiments are illustrated by way of example and described in detail in the accompanying drawings. However, it should be understood that this description is not intended to limit the invention to the specific embodiments, but rather, the invention is intended to cover all modifications, equivalents, and substitutions falling within the spirit and scope of the invention.

[0048] Although the terms “first,” “second,” etc., may be used herein to refer to various elements, such elements should not be construed as being limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and a second element may be referred to as a first element, without departing from the scope of the invention. The term “and / or” includes any one and all combinations of one or more of the listed items.

[0049] What will be understood is that when a component is referred to as "connected" or "coupled" to another component, it can be directly connected or coupled to the other component, or there can be intermediate components. Conversely, when a component is referred to as "directly connected" or "directly coupled" to another component, there are no intermediate components.

[0050] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the embodiments of the invention. As used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It will be further understood that, when used herein, the terms “comprising,” “including,” “containing,” and / or “comprising” specify the presence of the stated features, integers, steps, operations, elements, portions, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, portions, and / or combinations thereof.

[0051] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It will be further understood that, unless expressly defined herein, terms defined in common dictionaries shall be interpreted as having the same meaning as they have in the context of the prior art and shall not be interpreted in an idealized or overly formal sense.

[0052] In the following description, exemplary embodiments of the invention will be described in more detail with reference to the accompanying drawings. To facilitate an overall understanding of the invention, similar reference numerals will refer to similar elements throughout the description of the drawings, and descriptions of the same components will not be repeated.

[0053] Wireless communication networks according to exemplary embodiments of the present disclosure will be described. However, the wireless communication networks to which exemplary embodiments of the present disclosure are applied are not limited to those described below. That is, exemplary embodiments of the present disclosure can be applied to various wireless communication networks. Here, the term "communication system" may be used with the same meaning as the term "communication network".

[0054] Figure 1 This is a conceptual diagram illustrating a first exemplary embodiment of the communication system.

[0055] refer to Figure 1 The first base station 110 can support cellular communications (e.g., Long Term Evolution (LTE), LTE-A, LTE-APro, LTE-Unlicensed (LTE-U), New Radio (NR), and NR-unlicensed (NR-U) as specified in the 3GPP program). The first base station 110 can support Multiple-Input Multiple-Output (MIMO) (e.g., Single-User MIMO (SU-MIMO), Multi-User MIMO (MU-MIMO), Massive MIMO, etc.), Cooperative Multipoint (CoMP), Carrier Aggregation (CA), etc.

[0056] The first base station 110 can operate in frequency band F1 and can form a macro cell. The first base station 110 can be connected to another base station (e.g., the second base station 120, the third base station 130, etc.) via ideal or non-ideal backhaul. The second base station 120 can be located within the coverage area of ​​the first base station 110. The second base station 120 can operate in frequency band F2 and can form a small cell. The communication scheme (e.g., NR) supported by the second base station 120 can differ from the communication scheme of the first base station 110.

[0057] The third base station 130 may be located within the coverage area of ​​the first base station 110. The third base station 130 may operate in frequency band F2 and may form a small cell. The communication scheme (e.g., NR) supported by the third base station 130 may differ from the communication scheme of the first base station 110. Each of the first base station 110 and the user equipment (UE) (not shown) connected to the first base station 110 may transmit and receive signals via carrier aggregation (CA) between frequency bands F1 and F2. Alternatively, each UE connected to the first base station 110 and the first base station 110 may support dual connectivity (DC) for both frequency bands F1 and F2, and may transmit and receive signals in a DC environment.

[0058] The communication nodes (i.e., base stations, terminals, etc.) that constitute the above-mentioned wireless communication network can support communication protocols based on Code Division Multiple Access (CDMA), Wideband CDMA (WCDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Single Carrier FDMA (SC-FDMA), Orthogonal Frequency Division Multiplexing (OFDM), and Orthogonal Frequency Division Multiple Access (OFDMA), etc.

[0059] In these communication nodes, base stations can be referred to as Node B, Evolved Node B, 5G Node B (gNodeB), Base Transceiver Station (BTS), Radio Base Station, Radio Transceiver, Access Point, Access Node, Transmit / Receive Point (Tx / Rx Point), etc. In these communication nodes, terminals can be referred to as User Equipment (UE), Access Terminal, Mobile Terminal, Station, User Station, Portable User Station, Mobile Station, Node, Equipment, etc. Communication nodes can have the following structures.

[0060] Figure 2 This is a block diagram illustrating a first exemplary embodiment of a communication node constituting a communication system.

[0061] refer to Figure 2The communication node 200 may include a transceiver 230 connected to a network to perform communication, at least one processor 210, and a memory 220. Furthermore, the communication node 200 may also include an input interface device 240, an output interface device 250, a storage device 260, etc. Each component included in the communication node 200 can communicate with each other when connected via a bus 270.

[0062] However, each component included in communication node 200 may not be connected to the common bus 270, but may be connected to processor 210 via its own interface or a separate bus. For example, processor 210 may be connected to at least one of memory 220, transceiver 230, input interface device 240, output interface device 250 and storage device 260 via a dedicated interface.

[0063] Processor 210 can execute a program stored in at least one of memory 220 and storage device 260. Processor 210 may be a central processing unit (CPU), graphics processing unit (GPU), or dedicated processor, on which the methods according to embodiments of the present disclosure are executed. Each of memory 220 and storage device 260 may be constituted by at least one of volatile storage media and non-volatile storage media. For example, memory 220 may include at least one of read-only memory (ROM) and random access memory (RAM).

[0064] The operation methods of communication nodes in a communication network will be described below. Even if a method (e.g., transmitting or receiving a signal) to be performed at a first communication node is described, a corresponding second communication node can also perform a method (e.g., receiving or transmitting a signal) corresponding to the method performed at the first communication node. That is, when the operation of a terminal is described, the corresponding base station can perform an operation corresponding to the terminal's operation. Conversely, when the operation of a base station is described, the corresponding terminal can perform an operation corresponding to the base station's operation.

[0065] Figure 3 This is a conceptual diagram illustrating a first exemplary embodiment of a system frame in a communication system.

[0066] refer to Figure 3 Time resources in a communication network can be divided into frames. For example, system frames of 10 milliseconds (ms) in length can be configured consecutively on the timeline of the communication system. The system frame number (SFN) can be set to #0 to #1023. In this case, 1024 system frames can be repeated on the timeline of the communication system. For example, the SFN of system frames after system frame #1023 can be set to #0.

[0067] A system frame can include two half-frames, each half-frame having a length of 5ms. The half-frame located in the start region of the system frame can be called "half-frame #0", while the half-frame located in the end region of the system frame can be called "half-frame #1". A system frame can include 10 subframes, each subframe having a length of 1ms. The 10 subframes within a system frame can be called "subframes #0 to #9".

[0068] Figure 4 This is a conceptual diagram illustrating a first exemplary embodiment of a subframe in a communication system.

[0069] refer to Figure 4 A subframe can include n time slots, where n can be a natural number. Therefore, a subframe can consist of one or more time slots.

[0070] Figure 5 This is a conceptual diagram illustrating a first exemplary embodiment of a time slot in a communication system, and Figure 6 This is a conceptual diagram illustrating a second exemplary embodiment of a time slot in a communication system.

[0071] refer to Figure 5 and Figure 6 A time slot can include one or more symbols. Figure 5 A time slot, as shown, can consist of 14 symbols. Figure 6 A time slot, as shown, can consist of 7 symbols. Here, the length of the time slot can vary depending on the number and length of the symbols included in the time slot. Alternatively, the length of the time slot can be varied mathematically. When the subcarrier spacing is 15 kHz (e.g., μ = 0), the time slot length can be 1 ms. In this case, a system frame can include 10 time slots. When the subcarrier spacing is 30 kHz (e.g., μ = 1), the time slot length can be 0.5 ms. In this case, a system frame can include 20 time slots.

[0072] When the subcarrier spacing is 60 kHz (e.g., μ = 2), the time slot length can be 0.25 ms. In this case, a system frame can include 40 time slots. When the subcarrier spacing is 120 kHz (e.g., μ = 3), the time slot length can be 0.125 ms. In this case, a system frame can include 80 time slots. When the subcarrier spacing is 240 kHz (e.g., μ = 4), the time slot length can be 0.0625 ms. In this case, a system frame can include 160 time slots.

[0073] Symbols can be configured as downlink (DL) symbols, flexible symbols, or uplink (UL) symbols. A time slot consisting only of DL symbols is called a "DL time slot", a time slot consisting only of FL symbols is called a "FL time slot", and a time slot consisting only of UL symbols is called a "UL time slot".

[0074] Figure 7 This is a conceptual diagram of a first exemplary embodiment of time-frequency resources in a communication system.

[0075] refer to Figure 7 A resource with one OFDM symbol configured on the time axis and one subcarrier configured on the frequency axis can be defined as a "resource element (RE)". A resource with one OFDM symbol configured on the time axis and K subcarriers configured on the frequency axis can be defined as a "resource element group (REG)". A REG can include K REs. REG can be used as the basic unit for resource allocation on the frequency axis. K can be a natural number. For example, K can be 12. N can be a natural number. N is in Figure 5 The time slot shown can be 14, while N is... Figure 6 The time slot shown can contain 7. N OFDM symbols, which can be used as the basic unit for resource allocation on the time axis.

[0076] In the following exemplary embodiments, a method for transmitting and receiving data in a communication system will be described. Downlink data may be transmitted on a Physical Downlink Shared Channel (PDSCH). A base station may transmit PDSCH configuration information to a terminal on a Physical Downlink Control Channel (PDCCH). The terminal may obtain the PDSCH configuration information (e.g., scheduling information) by receiving the PDCCH (e.g., downlink control information (DCI)). For example, the PDSCH configuration information may include modulation and coding schemes (MCS) for PDSCH transmission and reception, PDSCH timing resource information, and PDSCH frequency resource information. The PDSCH may refer to the radio resources through which downlink data is transmitted and received. Alternatively, the PDSCH may represent the downlink data itself. The PDCCH may refer to the radio resources through which downlink control information (e.g., DCI) is transmitted and received. Alternatively, the PDCCH may refer to the downlink control information itself.

[0077] Figure 8 This is a conceptual diagram of a third exemplary embodiment of a time slot in a communication system.

[0078] refer to Figure 8A time slot can include 14 symbols on the time axis (e.g., in the time domain). These symbols can be OFDM symbols. Of these 14 symbols, one or more can be configured as PDCCH, while the remaining symbols can be configured as PDSCH. PDCCH can be mapped starting from the start symbol of the time slot (e.g., symbol #0). For example, PDCCH can be mapped to symbols #0 and #1. PDSCH can be mapped starting from the symbols following the end symbol of the PDCCH (e.g., symbol #1) (e.g., symbol #2). For example, PDSCH can be mapped to symbols #2 through #13. This mapping scheme can be called "PDSCH mapping type A". That is, when using PDSCH mapping type A, PDCCH can be mapped starting from the start symbol of the time slot, and PDSCH can be mapped starting from the symbols following the end symbol of the PDCCH. In this case, the length of the PDSCH on the time axis can be 4, 5, 6, 7, 8, 9, 10, 11, 12, or 13 symbols.

[0079] Figure 9 This is a conceptual diagram illustrating a fourth exemplary embodiment of a time slot in a communication system.

[0080] refer to Figure 9 A time slot can include 14 symbols on the time axis. PDCCH can be mapped to any one or more symbols within the time slot. That is, PDCCH may not be mapped to the starting symbol of the time slot (e.g., time slot #0). For example, PDCCH can be mapped to symbols #7 and #8. PDSCH can be mapped starting from the symbols following the ending symbol of the PDCCH (e.g., symbol #8) (e.g., symbol #9). For example, PDSCH can be mapped to symbols #9 through #13. The above mapping scheme can be called "PDSCH Mapping Type B". That is, when using PDSCH Mapping Type B, PDCCH can be mapped to any one or more symbols within the time slot, and PDSCH mapping can start from the symbols following the ending symbol of the PDCCH. In this case, the length of PDSCH on the time axis can be 2, 4, or 7 symbols.

[0081] The PDCCH monitoring method will be described in the following exemplary embodiments. A terminal may perform a PDCCH monitoring operation to receive PDSCH transmitted from a base station. The base station may use higher-layer messages (e.g., Radio Resource Control (RRC) messages) to notify the terminal of configuration information for the PDCCH monitoring operation. The configuration information for the PDCCH monitoring operation may include control resource set (CORESET) information and search space information.

[0082] CORESET information may include PDCCH demodulation reference signal (DMRS) information, PDCCH precoding information, and PDCCH timing information. The PDCCH DMRS can be the DMRS used for demodulating the PDCCH. The PDCCH timing can be an area where a PDCCH may exist; that is, a PDCCH timing can be an area where DCI can be transmitted. The PDCCH timing information may include time resource information and frequency resource information for the PDCCH timing. The length of the PDCCH timing on the time axis can be indicated in symbols. The size of the PDCCH timing on the frequency axis can be indicated in RBs (e.g., Physical Resource Blocks (PRBs) or Common Resource Blocks (CRBs)).

[0083] Search space information may include the identifier (ID) of the CORESET associated with the search space, the period of PDCCH monitoring, and the offset. Each of the periods and offsets of PDCCH monitoring can be indicated in time slots. Additionally, the search space information may include the index of the symbol at which the PDCCH monitoring operation began.

[0084] Figure 10 This is a conceptual diagram of a first exemplary embodiment of a PDCCH monitoring method in a communication system.

[0085] refer to Figure 10 The terminal can identify the location of the PDCCH timing based on CORESET information and search space information, and can perform monitoring operations within the PDCCH timing. The search space information can include a CORESET ID and can be associated with CORESET information having a corresponding CORESET ID. The length of the PDCCH timing on the time axis can be two symbols. The period of PDCCH monitoring can be one time slot, and the offset of PDCCH monitoring can be 0. The symbol at the start of the PDCCH monitoring operation can be symbol #0 within the time slot. The terminal can perform PDCCH monitoring operations for each time slot. PDCCH monitoring operations can be performed on symbols #0 and #1 within the time slot.

[0086] In the following exemplary embodiments, a method for transmitting and receiving signals and / or channels using variable bandwidth will be described. The signals may refer to reference signals or synchronization signals. Reference signals may be Channel State Information (CSI)-RS, DMRS, Tracking Reference Signal (TRS), Cell Reference Signal (CRS), Discovery Reference Signal (DRS), etc. Synchronization signals may be Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), etc. Channels may be downlink channels, broadcast channels, uplink channels, sidelink channels, etc. Downlink channels may be PDCCH, PDSCH, etc. Broadcast channels may be Physical Broadcast Channel (PBCH). Uplink channels may be Physical Uplink Shared Channel (PUSCH), Physical Uplink Control Channel (PUCCH), etc. Sidelink channels may be Physical Sidelink Shared Channel (PSSCH), Physical Sidelink Control Channel (PSCCH), Physical Sidelink Discovery Channel (PSDCH), Physical Sidelink Feedback Channel (PSFCH), etc.

[0087] A base station can configure a Bandwidth Part (BWP) for downlink communication. Each terminal can be configured with a different BWP. The base station can use higher-layer signaling to notify the terminal of the BWP configuration information. The number of BWPs configured for a terminal can be equal to or greater than one. The terminal can receive the BWP configuration information from the base station and can identify one or more BWPs configured by the base station based on the BWP configuration information. When multiple BWPs are configured for downlink communication, the base station can activate one or more of the multiple BWPs. The base station can use one or more of higher-layer signaling, Media Access Control (MAC) control elements (CE), and DCIs to send the configuration information of the activated one or more BWPs to the terminal. The base station can use the activated one or more BWPs to perform downlink communication. The terminal can identify the activated one or more BWPs by receiving the configuration information of the activated one or more BWPs from the base station and can perform downlink reception operations within the activated one or more BWPs.

[0088] Simultaneously, in the unlicensed band, the base station can perform a Listen-Before-Talk (LBT) operation to transmit downlink signals and / or channels. That is, the base station can use the LBT operation to identify whether radio resources are being used by another communication node. When the LBT operation determines that the radio resources are not being used by another communication node, the base station can use the radio resources to transmit downlink signals and / or channels. When the LBT operation determines that the radio resources are being used by another communication node, the base station can choose not to use the radio resources to transmit downlink signals and / or channels.

[0089] Figure 11This is a conceptual diagram of a first exemplary embodiment of an LBT subband in a communication system.

[0090] refer to Figure 11 LBT operations can be performed on top of LBT subbands. The width of each LBT subband can be different. Alternatively, the width of each LBT subband can be the same. An LBT subband can include one or more RBs. Here, an RB can be a PRB or a CRB. An LBT subband can be referred to as an "RB set" or "LBT bandwidth". The width of a BWP used for downlink communication can be X MHz. A BWP can include one or more LBT subbands.

[0091] The width of the LBT subband can be Y MHz. One or more LBT subbands can be configured by the base station. The base station can use one or more of higher-layer messages, MAC CE, and DCI to notify the terminal of the configuration information of one or more LBT subbands. The terminal can receive the configuration information of one or more LBT subbands from the base station and can identify the one or more LBT subbands configured by the base station based on this configuration information. The width of one or more LBT subbands can be less than or equal to the width of the BWP. For example, X can be 80, and Y can be 20. The base station can perform LBT operations in each of LBT subbands #1 to #4 and can transmit signals and / or channels in one or more LBT subbands where the LBT operation is successful. Signals and / or channels can be transmitted within the Channel Occupancy Time (COT) guaranteed by the base station.

[0092] One or more LBT subbands (e.g., one or more RB sets) can be configured within a BWP, a cell, or a carrier. The base station can transmit configuration information for one or more LBT subbands to the terminal using one or more of higher-layer signaling, MAC CE, and DCI. The configuration information for one or more LBT subbands may include one or more of the following: start position information, end position information, and size information of the LBT subband on the frequency axis. The start position information of the LBT subband may be the index of the starting RB, and the end position information of the LBT subband may be the index of the ending RB. The starting RB may be the starting PRB or the starting CRB, and the ending RB may be the ending PRB or the ending CRB. The starting RB may be the RB with the lowest frequency among the RBs belonging to the LBT subband (e.g., the RB with the smallest index). The ending RB may be the RB with the highest frequency among the RBs belonging to the LBT subband (e.g., the RB with the largest index). The size information of the LBT subband may indicate the number of RBs belonging to the LBT subband.

[0093] Information indicating the size of all LBT subbands belonging to the BWP can be set as a common size value. The location of the LBT subbands can be indicated by this common size value and its offsets. Each offset can be an interval from a specific point (e.g., point A) in each LBT subband to a start point (e.g., start RB), center point (e.g., center RB), or end point (e.g., end RB). Here, the specific point can be the start frequency position of a carrier (e.g., start subcarrier position or start RB), the start frequency position of the BWP (e.g., start subcarrier position or start RB), or point A of a CRB (e.g., CRB grid). The offsets can be configured in units of RBs. The center RB can be the RB with a center frequency among the RBs belonging to the LBT subband (e.g., the RB with a center index).

[0094] Figure 12 This is a conceptual diagram illustrating a first exemplary embodiment of a communication method using LBT subbands in a communication system.

[0095] refer to Figure 12 A base station can configure N LBT subbands within a BWP. N can be an integer equal to or greater than 1. The size (e.g., width) of the N LBT subbands on the frequency axis can be the same. Therefore, the size of the N LBT subbands can be indicated by the same value (e.g., a common size value). The common size value can be configured in units of RBs (e.g., CRB units). For example, each of the N LBT subbands can include K RBs. The position of each of the N LBT subbands can be indicated by a specific point and an offset. For example, the offset indicating the position of LBT subband #1 can be n1, while the offset indicating the position of LBT subband #2 can be n2. On the frequency axis, the offset can be the interval between the specific point of the corresponding LBT subband and the start point, center point, or end point. The offset can be configured in units of RBs.

[0096] The base station can use one or more of higher-layer signaling, MAC CE, and DCI to notify the terminal of LBT subband configuration information. The terminal can receive the LBT subband configuration information from the base station and can identify the number, size (e.g., size on the frequency axis), and location of the LBT subbands based on the configuration information. The LBT subband configuration information may include information indicating the size, offset, specific point, etc. of the LBT subbands.

[0097] A base station can configure an intra-carrier guard band between LBT subbands within a carrier. The intra-carrier guard band can be a guard band between LBT subbands. The intra-carrier guard band can be located at the edge of the LBT subband on the frequency axis. The intra-carrier guard band can be located between adjacent LBT subbands. The base station can use one or more of higher-layer signaling, MAC CE, and DCI to notify the terminal of the intra-carrier guard band configuration information.

[0098] The configuration information for the in-carrier guard band can include information indicating the size, number, and location of the in-carrier guard band on the frequency axis. The size of the in-carrier guard band can be configured in units of RBs (e.g., CRB units). The RB containing the in-carrier guard band can be called the guard RB (G-RB). The size of the in-carrier guard band may not be configured by the base station. In this case, the size of the in-carrier guard band can be the size defined in the 3GPP technical specifications. When the number of BWPs or LBT subbands configured within the carrier is N, the number of in-carrier guard bands configured within the BWP or carrier can be N-1. Alternatively, when the number of in-carrier guard bands configured within the BWP or carrier is N-1, the number of LBT subbands configured within the BWP or carrier can be equal to or greater than N.

[0099] The position of the in-carrier guard band on the frequency axis can be indicated by a specific point and an offset. The offset can be configured in units of RBs. The specific point can be the start point (e.g., start G-RB), center point (e.g., center G-RB), or end point (e.g., end G-RB) of the LBT sub-band adjacent to the in-carrier guard band. Alternatively, the specific point can be the start point (e.g., start RB) of the BWP to which the in-carrier guard band belongs, or point A of the CRB (e.g., CRB grid).

[0100] The configuration information for in-carrier guard bands may include start point information (e.g., start G-RB index) and end point information (e.g., end G-RB index) for the in-carrier guard bands. In this case, the in-carrier guard band on the frequency axis may consist of RBs from the start G-RB to the end G-RB. The G-RB index may be indicated based on the CRB index. When m in-carrier guard bands are configured within a cell, carrier, or BWP in an unlicensed band, the number of pairings between the start G-RB and end G-RB of each in-carrier guard band included in the configuration information may be m. m may be an integer equal to or greater than 1.

[0101] The terminal can receive configuration information of the in-carrier guard band from the base station, identify the BWP, carrier or cell in-carrier guard band (one or more) configured in the unlicensed band, and identify the LBT subband (e.g., one or more RB sets) configured in the BWP, carrier or cell based on the configuration of the in-carrier guard band (one or more).

[0102] When the number of pairings of the starting G-RB and ending G-RB of each in-carrier guard band included in the configuration information is m, the terminal can determine that (m+1) LBT subbands are configured within the BWP, carrier, or cell of the unlicensed band. The terminal can determine that the starting LBT subband among the (m+1) LBT subbands includes the RB (e.g., the starting CRB) of the BWP (or carrier, or cell) of the unlicensed band to the RB directly preceding the starting RB (e.g., the starting CRB) of the starting in-carrier guard band among the m in-carrier guard bands (i.e., an RB with a lower frequency than that starting RB). The starting LBT subband can be the LBT subband with the lowest frequency resource among the LBT subbands. The starting in-carrier guard band can be the in-carrier guard band with the lowest frequency resource among the in-carrier guard bands. The starting RB can be the RB with the lowest frequency resource among a specific RB.

[0103] The terminal can determine the ending LBT subband among (m+1) LBT subbands, including the RB (i.e., the RB with a higher frequency than the ending RB) immediately following the ending RB (e.g., the ending CRB) of the ending intra-carrier protection band in the m intra-carrier protection bands, to the ending RB (e.g., the ending CRB) of the BWP (or carrier or cell) in the unlicensed band. The ending LBT subband can be the LBT subband with the highest frequency resource among the LBT subbands. The ending intra-carrier protection band can be the intra-carrier protection band with the highest frequency resource among the intra-carrier protection bands. The ending RB can be the RB with the highest frequency resource among the specific RBs.

[0104] The terminal can determine each of the (m+1) LBT subbands, excluding the start and end LBT subbands, including the RB immediately following the end RB (e.g., end CRB) of the in-carrier guard band #p to the RB directly preceding the start RB (e.g., start CRB) of the in-carrier guard band #p+1. The LBT subband estimated by the terminal can lie between the in-carrier guard band #p and the in-carrier guard band #p+1. The frequency of the in-carrier guard band #p can be lower than the frequency of the in-carrier guard band #p+1. P can be an integer equal to or greater than 1.

[0105] Based on the above method, a base station can configure multiple intra-carrier guard bands within a carrier or cell. For example, the base station can notify the terminal of the start RB index (S1) and end RB index (E1) of the intra-carrier guard band (G1). The terminal can identify the intra-carrier guard band G1 configured by the base station based on the start RB index S1 and end RB index E1. Additionally, the base station can notify the terminal of the start RB index (S2) and end RB index (E2) of the intra-carrier guard band (G2). The terminal can identify the intra-carrier guard band G2 configured by the base station based on the start RB index S2 and end RB index E2. The base station can use one or more of higher-layer signaling, MAC CE, and DCI to send the configuration information of N intra-carrier guard bands within a carrier or cell to the terminal. The terminal can receive the configuration information of N intra-carrier guard bands from the base station and can identify the N intra-carrier guard bands based on the configuration information.

[0106] Each of the base station and the terminal can identify available RB(s) (e.g., one or more LBT subbands, one or more RB sets) based on the configuration information of the in-carrier guard band. For example, each of the base station and the terminal can determine one or more RB(s) in the BWP, carrier, or cell that do not include one or more in-carrier guard bands as available RB(s). Available RB(s) in the BWP, carrier, or cell can be one or more RBs located between in-carrier guard band G1 and in-carrier guard band G2. Available RB(s) in the BWP, carrier, or cell can be one or more RBs from the RB immediately following the end RB of in-carrier guard band G1 to the RB directly preceding the start RB of in-carrier guard band G2.

[0107] One or more available RBs can be the aforementioned LBT subbands or sets of one or more RBs. The base station can configure an in-carrier guard band for downlink communication and can configure an in-carrier guard band for uplink communication. The in-carrier guard band for downlink communication can be configured independently of the in-carrier guard band for uplink communication. The base station can use one or more of higher-layer signaling, MAC CE, and DCI to send configuration information of the in-carrier guard band for downlink communication and configuration information of the in-carrier guard band for uplink communication to the terminal.

[0108] The position of the in-carrier guard band on the frequency axis can be predefined. When the in-carrier guard band is not configured separately, the base station and terminal can identify the position of the in-carrier guard band and available resources (e.g., RBs, LBT sub-bands, RB sets) based on the predefined in-carrier guard band configuration. For example, the center position of the in-carrier guard band (e.g., center frequency or center RB) can be defined as the position with the same frequency offset from the two LBT sub-bands adjacent to the corresponding in-carrier guard band. Figure 12 In the exemplary embodiment shown, the center position of the in-carrier guard band that exists between LBT subband #1 and LBT subband #2 can be the center frequency between the center frequencies of LBT subband #1 and LBT subband #2, or the center RB between the center RB of LBT subband #1 and the center RB of LBT subband #2. The number, position, or size of the in-carrier guard band can be predefined.

[0109] The terminal can receive in-carrier guard band configuration information from the base station via one or more of higher-layer signaling, MAC CE, and DCI, and can identify the LBT subband configuration based on the in-carrier guard band configuration information. When no in-carrier guard band configuration information is received from the base station, the terminal can use a predefined in-carrier guard band configuration (e.g., defined in the 3GPP technical specifications).

[0110] Base stations and terminals may not perform signal and / or channel transmission / reception operations within the in-carrier guard band. Terminals may not perform radio resource management (RRM) measurements within the in-carrier guard band. For example, a terminal may perform RRM measurements in the BWP, carrier, or remaining frequency resources within the cell outside the in-carrier guard band.

[0111] The base station can send downlink scheduling information or uplink scheduling information to the terminal. The downlink scheduling information may include PDSCH allocation information, and the radio resources (e.g., frequency bands) indicated by the PDSCH allocation information may include one or more in-carrier guard bands. In this case, the terminal can perform rate matching or puncturing operations on the one or more in-carrier guard bands during the PDSCH transmission procedure. The uplink scheduling information may include PUSCH allocation information, and the radio resources (e.g., frequency bands) indicated by the PUSCH allocation information may include one or more in-carrier guard bands. In this case, the terminal can perform rate matching or puncturing operations on the one or more in-carrier guard bands during the PUSCH transmission process.

[0112] LBT operation may succeed in one or more LBT subbands among all LBT subbands included in the active BWP, while LBT operation may fail in the remaining (one or more) LBT subbands. In this case, the base station may transmit signals and / or channels as described in the following exemplary embodiments. Figure 12 In the exemplary embodiment shown, the base station can perform LBT operations in four LBT subbands. For example, the base station can perform energy detection operations in the LBT subbands, and when the detected energy level is less than or equal to a threshold, the terminal can determine that a signal and / or channel can be transmitted in the corresponding LBT subband. That is, the base station can determine that the LBT operation was successful in the corresponding LBT subband.

[0113] On the other hand, when the detected energy level in an LBT subband exceeds a threshold, the base station can determine that it cannot transmit signals and / or channels in the corresponding LBT subband. That is, the base station can determine that LBT operation has failed in the corresponding LBT subband. The base station can transmit signals and / or channels in one or more LBT subbands among all LBT subbands included in the active BWP where LBT operation has succeeded. The base station can perform rate matching or puncturing operations on (one or more) LBT subbands in which LBT operation has failed.

[0114] exist Figure 12 In the exemplary embodiment shown, the base station can determine that signals and / or channels can be transmitted in LBT subbands #1 and #2, and that signals and / or channels cannot be transmitted in LBT subbands #3 and #4. Therefore, the base station can use LBT subbands #1 and #2 to transmit signals and / or channels based on the result of performing LBT operations.

[0115] When LBT operation is successful in one or more LBT subbands included in the BWP, the base station can notify the terminal via one or more of higher-layer messages, MAC CE, and DCI, indicating whether downlink communication should be performed in one or more LBT subbands where the LBT operation was successful (hereinafter referred to as "DL indication information"). The DL indication information can indicate whether downlink communication should be performed in the LBT subbands within the BWP, carrier, or cell. The terminal can receive the DL indication information from the base station.

[0116] When it is determined that downlink communication is performed in one or more LBT subbands where LBT operation is successful, the terminal can estimate the BWP or (one or more) LBT subbands where downlink communication is performed based on DL indication information. Therefore, the terminal can perform downlink monitoring operations in the estimated BWP or (one or more) LBT subbands. Conversely, the terminal may choose not to perform downlink monitoring operations in LBT subbands where downlink communication is not estimated.

[0117] The base station can transmit signals and / or channels using one or more LBT subbands that are variably determined based on the result of LBT operations. The terminal may not be aware of the result of the LBT operations performed by the base station. In order to receive signals and / or channels transmitted from the base station, the terminal may need to know the frequency resources (e.g., one or more LBT subbands, one or more RB sets) used by the base station for transmitting signals and / or channels. The base station can inform the terminal of information about the frequency resources (e.g., information about one or more LBT subbands) within the active BWP used for downlink communication.

[0118] A base station can configure N LBT subbands (e.g., LBT bandwidth) within a BWP, a carrier, or a cell. Here, N can be an integer equal to or greater than 1. The size of each LBT subband can be Y MHz. Here, Y can be 20. Each LBT subband can include K RBs. Here, K can be an integer equal to or greater than 1. The base station can notify the terminal of the LBT subband configuration information within the BWP via one or more of higher-layer signaling, MACCE, and DCI. The LBT subbands within the BWP can be configured according to predefined information (e.g., size). When the size (e.g., width) of the LBT subbands within the BWP is configured according to predefined values, the number of LBT subbands within the BWP can be defined as Equation 1 below.

[0119] [Equation 1]

[0120] The number of LBT sub-bands within a BWP = (width of BWP) / (width of LBT sub-bands)

[0121] The LBT subbands within a BWP (or carrier, cell) can be configured based on a predefined width. In this case, the LBT subband indexes can be configured according to a predefined scheme. For example, the LBT subband indexes within a BWP can be configured based on the ascending or descending order of the corresponding RB indexes. Alternatively, the LBT subband indexes within a BWP can be configured based on the ascending or descending order of the corresponding frequencies.

[0122] The terminal can receive an RRC message (or MAC CE, DCI) containing LBT subband configuration information from the base station. Based on the configuration information included in the RRC message (or MAC CE, DCI), the terminal can identify the location and width of the LBT subbands within the BWP (or carrier or cell). Additionally, the terminal can identify the number of LBT subbands within the BWP (or carrier, cell) based on the configuration information included in the RRC message. For example, when N LBT subbands are configured within the BWP (or carrier, cell), the base station can send an RRC message containing N to the terminal. N can be indicated by a specific field included in the BWP configuration information or the cell RRC configuration information. Alternatively, information indicating the number of LBT subbands can be sent via MAC CE and / or DCI.

[0123] When N LBT subbands are configured within a BWP (or carrier, cell), the base station can send information indicating whether downlink communication should be performed in each of the N LBT subbands (e.g., DL indication information). The DL indication information can be a bitmap. When the BWP includes N LBT subbands, the bitmap size can be N bits. Figure 11 In the exemplary embodiment shown, the base station can configure four LBT subbands within the BWP. The base station can perform LBT operations in each of the N subbands. The base station can determine that downlink communication can be performed in one or more LBT subbands where the LBT operation was successful. The base station can generate a bitmap (e.g., DL indication information) indicating whether downlink communication is performed in each of the four LBT subbands, and can send the generated bitmap to the terminal.

[0124] The most significant bit (MSB) of the bitmap can be used for the LBT subband with the lowest RB index within the BWP. The remaining bits(s) of the bitmap can indicate the LBT subband(s) in ascending order of the RB indices within the BWP. Alternatively, the MSB of the bitmap can be used for the LBT subband with the highest RB index within the BWP. The remaining bits(s) of the bitmap can indicate the LBT subband in descending order of the RB indices within the BWP.

[0125] Bits set to "0" in the bitmap indicate that downlink communication is not performed in the corresponding LBT subband, while bits set to "1" indicate that downlink communication is performed in the corresponding LBT subband. The base station can send a bitmap (e.g., DL indication information) to the terminal indicating whether downlink communication is performed in each LBT subband. The size of the bitmap can vary depending on the configuration of the LBT subbands within the BWP. The size of the bitmap can be the same as the number of LBT subbands included in the BWP. The size of the bitmap can be indicated by an RRC message. For example, when N LBT subbands are configured in the BWP, the size of the bitmap can be N bits.

[0126] The terminal can receive a bitmap from the base station and identify, based on the bitmap, the LBT subbands within the BWP that perform downlink communication. The terminal can perform monitoring operations in one or more LBT subbands performing downlink communication, but not in one or more LBT subbands not performing downlink communication. The terminal can receive signals and / or channels from the base station based on the LBT subband configuration information. When a signal and / or channel is detected, the terminal can estimate the bandwidth of the detected signal and / or channel.

[0127] The base station can send a DCI (Distributed Control Interface) containing configuration information of the downlink communication bandwidth within a BWP (e.g., LBT subbands or RB sets used for downlink communication) to terminals. The DCI containing the downlink communication bandwidth configuration information can be sent to multiple terminals via a group common control channel (e.g., group common PDCCH). The base station can send the DCI containing the downlink communication bandwidth configuration information to one or more terminals that have an active BWP.

[0128] The base station can configure a group common control channel to indicate one or more LBT subbands (M LBT subbands) performing downlink communication within the BWP. A group common control channel can be configured for each LBT subband. Figure 12 In the exemplary embodiment shown, the base station can configure a group common control channel to instruct one or more LBT subbands (#1 to #4) within the BWP to perform downlink communication. The group common control channel can be configured in LBT subbands #1 and #2. Additionally, the base station can configure the group common control channel in LBT subbands #3 and #4. However, when LBT operation fails in LBT subbands #3 and #4, the base station may not transmit DCI in the group common control channel configured in LBT subbands #3 and #4. That is, downlink communication may not be performed in LBT subbands #3 and #4.

[0129] The base station can transmit information (e.g., DL indication information) indicating the execution of downlink communication in one or more LBT subbands via a group common control channel configured in each LBT subband. Figure 12 In the exemplary embodiment shown, the base station can transmit DL indication information indicating that downlink communication is performed in LBT subbands #1 and #2 in LBT subbands #1 to #4 through the common control channel of LBT subbands #1 and #2.

[0130] Alternatively, the base station can transmit DL indication information via the group common control channel of the corresponding LBT subband. Figure 12In the exemplary embodiment shown, the base station can transmit DL indication information indicating downlink communication in LBT subband #1 via the group common control channel of LBT subband #1, and transmit DL indication information indicating downlink communication in LBT subband #2 via the group common channel of LBT subband #2. The terminal can receive the DL indication information via the group common control channels of LBT subbands #1 and #2. In this case, the terminal can receive signals and / or channels by performing monitoring operations in LBT subbands #1 and #2. The terminal may not perform monitoring operations in LBT subbands #3 and #4.

[0131] When downlink communication is possible in one or more LBT subbands included in the BWP, the base station can transmit a DMRS for the CORESET associated with the common search space, through which resource structure indicators (e.g., DL indication information) are transmitted. Here, the precoder granularity of the DMRS can be the same as the size of the LBT subband. The base station can transmit configuration information for one or more LBT subbands(s) used for downlink communication via control channels configured in the common search space. The terminal can perform a DMRS detection operation in each LBT subband. The terminal can perform a control channel (e.g., resource structure indicator, DL indication information) detection operation in the common search space of the LBT subband where the DMRS is successfully detected. When a control channel (e.g., resource structure indicator, DL indication information) is successfully detected in an LBT subband, the terminal can determine to perform downlink communication in the corresponding LBT subband. The terminal can obtain the configuration information of the LBT subbands used for downlink communication by detecting the control channels in the LBT subbands.

[0132] A base station can transmit a Data Access Control (DCI) containing resource configuration information for the unlicensed band's Baseband Power Plan (BWP), such as a carrier or cell. This DCI can be transmitted via a Group Common Control Channel (CCC). The DCI may include one or more of the following: frequency resource information for the unlicensed band, time slot configuration information, and Channel Occupied Time (COT) information. The COT indicated by the DCI may be a COT protected by the base station. The time slot configuration information may include the location and number of DL time slots, Flexible (FL) time slots, and UL time slots. The frequency resource information may include configuration information for LBT subbands used for downlink communication. A terminal can receive the DCI by detecting a control channel (e.g., a CCC) in the unlicensed band and can identify the frequency resource information, time slot configuration information, and / or COT information included in the DCI. Here, the control channel (e.g., the CCC) may be located in a common search space.

[0133] The terminal can perform DMRS detection or Group Common Control Channel detection operations to estimate the downlink transmission bandwidth of the base station in the unlicensed band. Figure 12 In the exemplary embodiment shown, the terminal can estimate which LBT subbands (#1 to #4) included in the BWP are performing downlink communication. The terminal can identify whether downlink communication is performing in these LBT subbands by performing a DMRS detection operation in the LBT subbands. The terminal can perform a Group Common Control Channel Detection operation in the LBT subbands where DMRS is successfully detected.

[0134] The terminal can perform group common control channel (CCC) detection operations in each LBT subband. The terminal can identify resource structure information of the LBT subband where the CCC is detected. For example, when a CCC is detected, the terminal can identify the location and number of downlink time slots and uplink time slots in the corresponding LBT subband. The terminal can perform downlink monitoring operations based on the resource structure, which is estimated based on information obtained through the detected CCC.

[0135] For example, a terminal may perform downlink monitoring operations within the downlink symbols and / or downlink time slots indicated by a DCI (e.g., a resource structure indicator) obtained via a group common control channel. A terminal may not perform downlink monitoring operations within the uplink symbols and / or uplink time slots indicated by a DCI (e.g., a resource structure indicator) obtained via a group common control channel. A terminal may not perform DMRS detection operations to estimate LBT subband configuration information within the downlink symbols, downlink time slots, uplink symbols, and / or uplink time slots indicated by a DCI (e.g., a resource structure indicator). A terminal may perform DMRS detection operations to estimate LBT subband configuration information within time resources following the downlink resources or uplink resources indicated by a DCI (e.g., a resource structure indicator).

[0136] exist Figure 12 In the exemplary embodiment shown, the terminal can perform a DMRS detection operation in time slot #n to estimate the configuration information of the LBT subband. The terminal can perform the DMRS detection operation in LBT subbands #1 to #4 within the active BWP. The terminal can detect DMRS in LBT subbands #1 and #2 of time slot #n, but may not detect DMRS in LBT subbands #3 and #4 of time slot #n. The terminal can perform a Group Common Control Channel (DCC) detection operation in LBT subbands #1 and #2 where DMRS is detected. That is, the terminal can obtain the DCI (e.g., Resource Structure Indicator) through the DCC in LBT subbands #1 and #2 of time slot #n.

[0137] The terminal can determine, based on the DCI (e.g., resource structure indicator), that the frequency resources for performing downlink communication are LBT subbands #1 and #2. Additionally, the terminal can determine, based on the DCI (e.g., resource structure indicator), that the time resources for performing downlink communication are time slots #n to #n+2. Therefore, the terminal can perform downlink monitoring operations in LBT subbands #1 and #2 of time slots #n to #n+2. Alternatively, the terminal can choose not to perform DMRS detection operations in LBT subbands #1 and #2 of time slots #n+1 and #n+2 to estimate the configuration information of the LBT subbands.

[0138] The terminal can identify whether downlink communication has been performed in the corresponding LBT subband by performing a PDCCH DMRS detection operation in the CORESET configured in the LBT subband. Figure 12 In the exemplary embodiment shown, the terminal can perform PDCCH DMRS detection operations in LBT subbands #1 to #4. When the base station transmits signals and / or channels in LBT subbands #1 and #2, the terminal can detect PDCCH DMRS in LBT subbands #1 and #2. The terminal may not detect PDCCH DMRS in LBT subbands #3 and #4. The terminal can determine to perform downlink communication in one or more LBT subbands where PDCCH DMRS is detected. The terminal can perform downlink monitoring operations in one or more LBT subbands where PDCCH DMRS is not detected. In one or more LBT subbands where PDCCH DMRS is not detected, the terminal may not perform downlink monitoring operations.

[0139] For each LBT subband's PDCCH DMRS detection operation, the base station can configure PDCCH DMRS in the unlicensed band's BWP (e.g., carrier, cell) based on predefined information. For example, the PDCCH DMRS configured in the unlicensed band's BWP (e.g., carrier, cell) can be wideband PDCCH DMRS. The base station can configure precoder granurality in the unlicensed band's BWP (e.g., carrier, cell), including consecutive RBs within the CORESET. Here, the precoder granurality can be the CORESET's precoder granurality. In this case, the base station can perform precoding operations on the PDCCH DMRS in consecutive RBs in the LBT subband based on the CORESET's precoder granurality and can transmit the precoded PDCCH DMRS.

[0140] The terminal can determine whether downlink communication has been performed in the LBT subband by performing a PDCCH DMRS detection operation. The base station can transmit a PDCCH DMRS with a precoder granurality equal to the size of the LBT subband in the first symbol. Here, the first symbol may belong to the first time slot of a time period (e.g., COT) used for downlink communication. The terminal can determine whether downlink communication has been performed in the LBT subband by performing a PDCCH DMRS detection operation in the first symbol. When it is determined that downlink communication has been performed in the LBT subband, the terminal can perform monitoring operations on signal and / or channel reception in the corresponding LBT subband.

[0141] The base station can transmit PDCCH DMRS in the transmission area corresponding to the common search space within the BWP (e.g., carrier, cell) of the unlicensed band. Here, PDCCH DMRS can be wideband PDCCH DMRS, and the common search space can be used to transmit DCI including slot structure indicators and / or burst structure indicators (e.g., COT structure indicators) of the unlicensed band.

[0142] When the common search space within the unlicensed band's BWP (e.g., carrier, cell) is used to transmit DCI including unlicensed band slot structure indicators and / or burst structure indicators (e.g., COT structure indicators), the precoder granurality of the CORESET associated with the common search space can consist of consecutive RBs within the CORESET. The base station can perform the same precoding operation on PDCCH DMRS in consecutive RBs within the LBT subband based on the precoder granurality and can transmit the precoded PDCCH DMRS. The terminal can determine whether downlink communication has been performed in the LBT subband by performing a PDCCH DMRS detection operation. The terminal can perform monitoring operations on signals and / or channels in the LBT subband where PDCCH DMRS is detected. The terminal may not perform monitoring operations on signals and / or channels in the LBT subband where PDCCH DMRS is not detected.

[0143] The precoder granurality of the CORESET associated with the common search space in the unlicensed band's BWP (e.g., carrier, cell) (e.g., the precoder granurality of the DMRS associated with the CORESET) can be the same size as the LBT subband, and the base station can transmit the corresponding DMRS (e.g., PDCCH DMRS). The common search space can be used to transmit DCIs that include slot structure indicators and / or burst structure indicators (e.g., COT structure indicators) of the unlicensed band.

[0144] For the first downlink transmission within the COT in an unlicensed band BWP (e.g., a carrier), the precoder granurality of the CORESET associated with the common search space (e.g., the precoder granurality of the DMRS associated with the CORESET) can be the same size as the LBT subband, and the base station can transmit the corresponding DMRS (e.g., PDCCHDMRS). The length of the first downlink transmission within the COT can be the same as a time slot. Alternatively, the length of the first downlink transmission within the COT can be shorter than a time slot. The common search space can be used to transmit DCIs that include time slot structure indicators and / or burst structure indicators (e.g., COT structure indicators) for the unlicensed band.

[0145] The terminal can perform a DMRS (e.g., PDCCH DMRS) detection operation for downlink communication. The terminal can obtain configuration information (e.g., number, location, and size) of LBT subbands performing downlink communication by performing the DMRS detection operation. The terminal can perform downlink monitoring operations in the LBT subbands indicated by the obtained configuration information. The terminal can also perform downlink monitoring operations in one or more LBT subbands not indicated by the LBT subband configuration information within the BWP.

[0146] The base station can send frequency resource information for the unlicensed band BWP, carrier, and / or cell to the terminal. For example, this frequency resource information may include information about LBT subbands (e.g., number, location, and size). Furthermore, this frequency resource information may include information indicating one or more LBT subbands that are not performing downlink communication. This frequency resource information can be included in the DCI and can be transmitted via the group common control channel.

[0147] The terminal can receive the DCI from the base station by performing a monitoring operation on the group common control channel and can identify the frequency resource information included in the DCI. The DCI can be received in a common search space or a terminal-specific (i.e., UE-specific) search space. The terminal can identify one or more LBT subbands that perform downlink communication based on the frequency resource information. Additionally, the terminal can identify one or more LBT subbands that do not perform downlink communication based on the frequency resource information.

[0148] The base station can use one or more LBT subbands within the BWP to perform downlink communication. The terminal can perform DMRS or DCI detection operations to estimate one or more LBT subbands(s) performing downlink communication within the BWP. Figure 12In the exemplary embodiment shown, the base station can use LBT subbands #1 and #2, which are one or more LBT subbands within the BWP, to perform downlink communication. The base station can transmit DMRS in LBT subbands #1 and #2. The base station can transmit a DCI including information indicating LBT subbands #1 and #2 (e.g., DL indication information), wherein downlink communication is performed via LBT subbands #1 and #2. Here, the DCI can be transmitted via a group common control channel.

[0149] The terminal can receive a DCI from the base station and can estimate one or more LBT subbands (#1 to #4) in which downlink communication is performed based on the information included in the DCI. For example, the terminal can determine whether downlink communication is to be performed in an LBT subband by detecting DMRS (e.g., PDCCH DMRS) in the LBT subband. The terminal can determine that downlink communication is to be performed in the LBT subband where DMRS is detected.

[0150] The terminal can perform a DCI detection operation to obtain information (e.g., DL indication information) indicating the LBT subband for downlink communication. The DCI detection operation can be performed on a group common control channel. The terminal can receive the DCI in a common search space or a UE-specific search space. For example, the terminal can perform the DCI detection operation in an LBT subband where PDCCH DMRS is detected, and determine whether to perform downlink communication in the LBT subband based on the information included in the DCI. The terminal can perform a downlink monitoring operation in an LBT subband where downlink communication is performed. In an LBT subband where downlink communication is not performed, the terminal may not perform a downlink monitoring operation.

[0151] CSI-RS resources can be configured across multiple LBT subbands. The base station can send CSI-RS configuration information across these multiple LBT subbands to the terminal via one or more of higher-layer signaling, MAC CE, and DCI. The terminal can receive the CSI-RS configuration information from the base station and determine, based on this information, that CSI-RS resources have been configured across multiple LBT subbands.

[0152] In this scenario, when it is determined that downlink communication is performed in all LBT subbands configured with CSI-RS resources, the terminal can determine that CSI-RS is transmitted in all LBT subbands (e.g., multiple LBT subbands indicated by the base station). When downlink communication is not performed in one or more LBT subbands among all LBT subbands configured with CSI-RS resources, the terminal can determine that CSI-RS is not transmitted. Here, the terminal can determine that CSI-RS is not transmitted in all LBT subbands configured with CSI-RS or in one or more LBT subbands where downlink communication is not performed. In this case, the terminal may not perform CSI-RS measurement operations or CSI reporting operations.

[0153] The base station can transmit COT configuration information via a control channel (e.g., a group common control channel). Alternatively, the COT configuration information can be transmitted via higher-layer signaling and / or MAC CE. The COT configuration information may include one or more of the following: COT time resource information, COT frequency resource information, LBT priority information used by the base station to configure the COT, and LBT operation types used by the terminal to perform communication within the COT. The terminal can receive the COT configuration information via higher-layer signaling, MAC CE, or DCI. For example, the terminal can receive the COT configuration information via the group common control channel. The terminal can perform downlink monitoring operations and / or uplink transmission operations within the COT based on the COT configuration information.

[0154] A base station can protect a COT by performing LBT operations. The configuration of the COT can vary depending on the type of LBT operation performed by the base station (e.g., LBT category 1 to 4). For example, the maximum length of the COT can vary depending on the type of LBT operation performed by the base station. The type of LBT operation performed by the base station can vary depending on the priority category of the data to be transmitted within the COT. The base station can use different LBT parameters to perform LBT operations to protect the COT corresponding to each priority category. When performing LBT operations according to priority categories, the parameters determining the execution time of the LBT operation can be different. In LBT operations involving random backoff procedures, the minimum and / or maximum size of the contention window used to derive the random backoff counter can be configured differently for each priority category.

[0155] The base station can protect the COT by performing LBT operations based on the above method, and can send the configuration information of the protected COT to the terminal. The COT configuration information may include LBT parameters used by the base station to perform the LBT operations. For example, LBT parameters may include priority category information. The terminal can receive the COT configuration information from the base station and can identify the LBT parameters used to protect the COT based on the COT configuration information.

[0156] The base station can send the COT configuration information protected by LBT operation to the terminal. The COT configuration information may include one or more of the following: the start time of the COT, the duration of the COT, and the end time of the COT. The duration of the COT can be the length from the transmission time of the group common control channel including the COT configuration information to the end time of the COT. For example, when the COT is configured to run from time t to time t+n, and the COT configuration information is transmitted at time t+k before time t+n, the duration of the COT can indicate nk. The terminal can receive the COT configuration information from the base station and determine, based on the COT configuration information, whether the COT includes downlink communication periods and / or uplink communication periods.

[0157] Furthermore, the COT configuration information may include one or more of the following: burst signal configuration information, information indicating the format of time periods, symbols, or time slots within the COT, and PDCCH configuration information within the COT (e.g., PDCCH timing configuration information). The COT configuration information can be transmitted via one or more of higher-level signaling, MAC CE, and DCI. For example, a terminal can receive the COT configuration information via the group common control channel and can perform monitoring operations on the PDCCH timing indicated by the COT configuration information.

[0158] Information indicating the time slot format can indicate whether the time slot included in the COT is a DL time slot, FL time slot, or UL time slot. Information indicating the symbol format can indicate whether the symbol included in the COT is a DL symbol, FL symbol, or UL symbol. Information indicating the time period format can indicate whether the time period in the COT is a DL time period, FL time period, or UL time period. The terminal can perform PDCCH monitoring operations in DL time slots, FL time slots, DL symbols, FL symbols, DL time periods, and / or FL time periods within the COT. PDCCH monitoring operations can be omitted in UL time slots, UL symbols, and UL time periods.

[0159] Information indicating whether downlink communication is performed in an LBT subband (e.g., DL indication information) can be included in the COT's frequency domain configuration information (e.g., frequency resource information). The base station can perform LBT operations in each LBT subband and protect the COT in one or more LBT subbands where the LBT operation is successful. The frequency resources of the COT can be configured according to the one or more LBT subbands where the LBT operation is successful. The COT's frequency resource information and time resource information can be transmitted via a group common control channel (e.g., the same group common control channel). The COT's frequency resource information and time resource information can be included in the same DCI. The DCI can include a field indicating the COT's frequency resource information and a field indicating the COT's time resource information. The COT's frequency resource information can be jointly encoded with the COT's time resource information in the same DCI. In this case, the COT's frequency resource information and time resource information can be indicated by a field included in the DCI.

[0160] The terminal can receive COT frequency resource information from the base station and identify the COT frequency resources based on this information. The terminal can also receive COT time resource information from the base station and identify the COT time resources based on this information. The terminal can perform downlink monitoring operations on radio resources configured as COT (e.g., time and frequency resources). The terminal may choose not to perform downlink monitoring operations on radio resources not configured as COT (e.g., time and frequency resources).

[0161] The base station can send information to the terminal indicating one or more LBT subbands for performing downlink communication or belonging to one or more LBT subbands of a COT protected by the base station. Additionally, the base station can send time resource information of the COT protected by the base station to the terminal. The one or more LBT subbands for performing downlink communication or belonging to one or more LBT subbands of a COT protected by the base station can be valid within the time resources (e.g., time periods) of the COT.

[0162] For example, a base station can send information to a terminal indicating an LBT subband #n for performing downlink communication or an LBT subband #n belonging to a COT protected by the base station, and also send time resource information of the COT protected by the base station to the terminal. The terminal can determine that the LBT subband #n is valid during the COT's time period based on the information received from the base station. After the COT's time period ends, the terminal can determine that the LBT subband #n is invalid.

[0163] The configuration information of one or more LBT subbands performing downlink communication within the COT may differ from the configuration information of one or more LBT subbands performing downlink communication outside the COT. Similarly, the configuration information of one or more LBT subbands performing downlink communication during a downlink burst may differ from the configuration information of one or more LBT subbands performing downlink communication outside the downlink burst period.

[0164] Configuration information for one or more LBT subbands performing downlink communication within the COT or during downlink burst periods may include information indicating whether downlink communication is performed in one or more LBT subbands (e.g., DL indication information). For example, DL indication information indicating whether downlink communication is performed in LBT subband #n may be sent via LBT subband #n. DL indication information sent via LBT subband #n may not include information indicating whether downlink communication is performed in another LBT subband. Information indicating whether downlink communication is performed in another LBT subband may be meaningless. The terminal may ignore information indicating whether downlink communication is performed in another LBT subband.

[0165] exist Figure 12 In the exemplary embodiment shown, the base station can send DL indication information to the terminal, indicating whether downlink communication is to be performed in the LBT subband, through the time slot #n to which the COT or the start time of the downlink burst belongs. The DL indication information sent through LBT subband #1 of time slot #n can indicate whether downlink communication is to be performed in LBT subband #1. The size of the DL indication information can be 1 bit. The DL indication information sent through LBT subband #1 of time slot #n may not include information indicating whether downlink communication is to be performed in one or more LBT subbands other than LBT subband #1.

[0166] The terminal can determine whether to perform downlink communication in LBT subband #1 based on DL indication information received from the base station. The terminal can receive DL indication information in each LBT subband to determine whether to perform downlink communication in each LBT subband. The base station can independently transmit DL indication information within the time period (e.g., time slot) to which the start time of the COT or downlink burst belongs. The terminal can identify the frequency resources (e.g., one or more LBT subbands) for performing downlink communication within the BWP based on the DL indication information.

[0167] DL indication information can be a bitmap. In this case, the base station can send a bitmap indicating whether downlink communication should be performed in each LBT subband within the time period (e.g., a time slot) to which the COT or downlink burst start time belongs. Figure 12In the exemplary embodiment shown, bits indicating whether downlink communication is performed in LBT subband #1 (e.g., bits included in the bitmap) can be transmitted via LBT subband #1 of time slot #n.

[0168] The terminal can receive DL indication information within the time period (e.g., time slot) to which the start time of the COT or downlink burst belongs. The terminal can use all DL indication information received in the LBT subband to identify the frequency resources (e.g., one or more LBT subbands) for performing downlink communication within the BWP.

[0169] The base station can send DL indication information (e.g., bits) for each LBT subband. Figure 12 In the exemplary embodiment shown, when the LBT operation is successful in LBT subbands #1 and #2, the base station can send DL indication information (e.g., information of 1 bit size) indicating downlink communication to be performed in LBT subband #1 via LBT subband #1, and send DL indication information (e.g., information of 1 bit size) indicating downlink communication to be performed in LBT subband #2 via LBT subband #2. Information set to "0" can indicate downlink communication to be performed in the corresponding LBT subband. Alternatively, information set to "1" can indicate downlink communication to be performed in the corresponding LBT subband.

[0170] LBT operations in LBT subbands #3 and #4 may fail. In this case, downlink communication may not be performed in LBT subbands #3 and #4. The base station may not send DL indication information indicating that downlink communication will not be performed through LBT subbands #3 and #4. The terminal may determine, based on information received from the base station, to perform downlink communication in LBT subbands #1 and #2 within the BWP. Furthermore, the terminal may determine that downlink communication will not be performed in subbands #3 and #4 within the BWP.

[0171] When the BWP includes N LBT subbands, the base station can configure a bitmap including N bits (e.g., DL indication information) to indicate whether downlink communication should be performed in the N LBT subbands. Each of the N bits included in the bitmap can correspond to each of the N LBT subbands included in the BWP. Figure 12 In the exemplary embodiment shown, the BWP may include four LBT subbands, and the base station may configure a bitmap including four bits to indicate whether downlink communication is performed in the four LBT subbands.

[0172] The base station can transmit a bitmap indicating whether downlink communication will be performed in LBT subband #m within the time period (e.g., time slot #n) to which the start time of the COT or downlink burst belongs. Each of n and m can be an integer equal to or greater than 0. The bitmap transmitted through LBT subband #m in time slot #n may not include information indicating whether downlink communication will be performed in the remaining LBT subbands other than LBT subband #m included in the BWP.

[0173] exist Figure 12 In the exemplary embodiment shown, DL indication information can be transmitted in each LBT subband of the time slot #n to which the start time of the COT or downlink burst belongs. The DL indication information (e.g., a bitmap) transmitted via LBT subband #m of time slot #n may include information indicating whether downlink communication is performed in LBT subband #m, as well as information about one or more LBT subbands other than LBT subband #m. The information about one or more LBT subbands other than LBT subband #m may be configured to preset values ​​(e.g., "0" or "1"). Among the bits included in the bitmap (e.g., DL indication information), the bits corresponding to one or more LBT subbands other than LBT subband #m may be configured to preset values ​​(e.g., "0" or "1").

[0174] When the BWP includes four LBT subbands, the size of the bitmap indicating whether downlink communication is performed in each LBT subband can be four bits. In this bitmap, the first bit can indicate whether downlink communication is performed in LBT subband #1, the second bit can indicate whether downlink communication is performed in LBT subband #2, the third bit can indicate whether downlink communication is performed in LBT subband #3, and the fourth bit can indicate whether downlink communication is performed in LBT subband #4.

[0175] The bitmap for transmission via LBT subband #1 in time slot #n can be set to "1000". A bitmap set to "1000" indicates downlink communication in LBT subband #1. Bits in the bitmap corresponding to LBT subbands other than LBT subband #1 can be set to "0". The bitmap for transmission via LBT subband #2 in time slot #n can be set to "0100". A bitmap set to "0100" indicates downlink communication in LBT subband #2. Bits in the bitmap corresponding to LBT subbands other than LBT subband #2 can be set to "0".

[0176] The terminal can receive bitmaps from each LBT subband in time slot #n and identify whether downlink communication is performed in each LBT subband based on the bitmaps. The terminal can identify the LBT subbands performing downlink communication within the BWP by combining the bitmaps received in each LBT subband. For example, the terminal can receive a bitmap set to "1000" in LBT subband #1 and a bitmap set to "0100" in LBT subband #2. The terminal can determine whether downlink communication is performed in LBT subbands #1 and #2 within the BWP by combining the bitmaps received in LBT subband #1 and LBT subband #2. The terminal can perform OR operations on the bitmaps received in LBT subband #1 and LBT subband #2. For example, a terminal can derive “1100” by performing an operation (“1000” or “0100”), and can determine the execution of downlink communication in LBT subbands #1 and #2 within the BWP based on “1100”.

[0177] When the BWP includes N LBT subbands, the terminal can receive m bitmaps in m of the N LBT subbands. m can be a natural number equal to or less than N. The terminal can perform an OR operation on the m bitmaps and identify one or more LBT subbands within the BWP that perform downlink communication based on the result of the OR operation.

[0178] The bitmap transmitted via the time slot #n to which the start time of the COT or downlink burst belongs can be configured with a predefined value. This predefined value may not indicate whether downlink communication is performed in the LBT subband. The terminal can perform downlink monitoring operations regardless of the bitmap received in the time slot #n to which the start time of the COT or downlink burst belongs. Downlink monitoring operations can be performed on the configured LBT subband regardless of the bitmap received in the time slot #n to which the start time of the COT or downlink burst belongs.

[0179] DL indication information can be sent outside the time period of the COT or downlink burst start time. In this case, the DL indication information can indicate whether downlink communication is performed in other (one or more) LBT subbands and in the LBT subband that sent the DL indication information. The terminal can receive the DL indication information and identify whether downlink communication is performed in each LBT subband within the BWP based on the DL indication information.

[0180] exist Figure 12In the exemplary embodiment shown, the base station can send DL indication information to the terminal in a time slot #n+2 where the start time of the COT or downlink burst does not belong. The DL indication information sent in time slot #n+2 can indicate whether downlink communication is performed in each of LBT subbands #1 to #4. The DL indication information sent via LBT subband #1 in time slot #n+2 can indicate whether downlink communication is performed in both LBT subbands #2 to #4 and LBT subband #1. The DL indication information sent via LBT subband #1 in time slot #n+2 may include bits indicating whether downlink communication is performed in LBT subband #1 and bits indicating whether downlink communication is performed in LBT subbands #2 to #4. The bits indicating whether downlink communication is performed in LBT subband #1 and the bits indicating whether downlink communication is performed in LBT subbands #2 to #4 can be located in the same field (e.g., the same field included in DCI).

[0181] The terminal can obtain DL indication information (e.g., fields included in the DCI) from the base station and identify whether downlink communication is performed in LBT subband #1 based on the DL indication information. Additionally, the terminal can identify whether downlink communication is performed in each of LBT subbands #2 to #4 based on the DL indication information. The terminal can also identify whether downlink communication is performed in all LBT subbands belonging to the BWP based on DL indication information received from one or more LBT subbands within the BWP.

[0182] The terminal can estimate that the DL indication information received through the LBT subbands within the BWP is the same as each other. For example, the terminal can estimate that the DL indication information received in LBT subband #n is the same as the DL indication information received in LBT subband #m. When the DL indication information received in LBT subband #n is different from the DL indication information received in LBT subband #m, the terminal can ignore the DL indication information. In this case, the terminal can perform downlink monitoring operations in the LBT subband that is indicated by the corresponding DL indication information as not performing downlink communication. The terminal can combine the DL indication information received in each LBT subband within the BWP and can identify whether the LBT subband within the BWP is performing downlink communication based on the combined DL indication information. To identify whether downlink communication is performing in the LBT subband within the BWP, the terminal can perform OR operations on the DL indication information (e.g., bitmap) received in the LBT subband within the BWP.

[0183] A bitmap (e.g., DL indication information) transmitted via LBT subband #m in time slot #n+2, but not within the time period corresponding to the start time of the COT or downlink burst, can indicate whether downlink communication is performed in LBT subband #m. Furthermore, a bitmap (e.g., DL indication information) transmitted via LBT subband #m in time slot #n+2 can indicate whether downlink communication is performed in one or more other LBT subbands besides LBT subband #m. The bitmap (e.g., DL indication information) can be included in the DCI.

[0184] The bitmap (e.g., DL indication information) can be indicated by the same field in the DCI (e.g., different bits constituting the same field). The terminal can receive the DCI from the base station, identify the bitmap (e.g., DL indication information) included in the DCI, and identify whether downlink communication is being performed in the LBT subband within the BWP based on the bitmap (e.g., DL indication information). The DL indication information (e.g., bitmap) transmitted by each LBT subband in the time period belonging to the start time point of time slot #n+2, rather than COT or downlink burst, can indicate whether downlink communication is being performed in the corresponding LBT subband.

[0185] exist Figure 12 In the exemplary embodiment shown, when the BWP includes four LBT subbands, the size of the bitmap indicating whether downlink communication is performed in the four LBT subbands can be four bits. Each of the four bits included in this bitmap can correspond to each of LBT subbands #1 to #4. The base station can transmit a bitmap set to "1100" through LBT subband #1 in time slot #n+2, and also through LBT subband #2 in time slot #n+2. The bitmap transmitted in LBT subband #1 in time slot #n+2 can be the same as the bitmap transmitted in LBT subband #2 in time slot #n+2.

[0186] The terminal can receive bitmaps (e.g., DL indication information) in each LBT subband and identify whether downlink communication is being performed in the LBT subbands within the BWP based on the bitmaps. The terminal can receive a bitmap set to "1100" in LBT subband #1 and determine whether downlink communication is being performed in LBT subbands #1 and #2 based on that bitmap. Similarly, the terminal can receive a bitmap set to "1100" in LBT subband #2 and determine whether downlink communication is being performed in LBT subbands #1 and #2 based on that bitmap.

[0187] The terminal can combine DL indication information (e.g., bitmaps) received through LBT subbands within the BWP, and can identify whether downlink communication is to be performed in the LBT subbands within the BWP based on the combined DL indication information. For example, the terminal can perform an OR operation on the bitmaps received in the LBT subbands. When the BWP includes m LBT subbands, the terminal can receive bitmaps (e.g., DL indication information) through multiple LBT subbands among the m LBT subbands, can perform an OR operation on the received bitmaps, and can identify whether downlink communication is to be performed in the m LBT subbands based on the result of the OR operation.

[0188] exist Figure 12 In the exemplary embodiment shown, when the bitmap received via LBT subband #1 is '1000' and the bitmap received via LBT subband #2 is '0100', the terminal can derive '1100' by performing an operation ('0100' or '1000'). The terminal can then determine whether to perform downlink communication in LBT subbands #1 and #2 based on '1100'.

[0189] The terminal can estimate that the DL indication information received through the LBT subband is the same. When the DL indication information received through the LBT subband is different, the terminal can ignore the corresponding DL indication information. When the DL indication information (e.g., bitmap) received through the LBT subband is different, the terminal can perform an OR operation on the corresponding bitmap and can identify whether the LBT subband within the BWP is performing downlink communication based on the result of the OR operation. The terminal can perform downlink monitoring operations in one or more LBT subbands that are determined to be performing downlink communication. Moreover, the terminal can choose not to perform downlink monitoring operations in one or more LBT subbands that are determined not to be performing downlink communication.

[0190] DL indication information transmitted during a time period (e.g., a time slot) that does not fall within the start time of the COT or downlink burst can indicate whether downlink communication should be performed in one or more LBT subbands other than the LBT subband that transmitted the corresponding DL indication information. For example, the DL indication information may include information indicating whether downlink communication should be performed in the LBT subband that transmitted the DL indication information and / or information indicating whether downlink communication should be performed in one or more LBT subbands other than the LBT subband that transmitted the DL indication information. The terminal can identify whether downlink communication should be performed in each LBT subband within the BWP based on the DL indication information received from the base station.

[0191] A Base Station (BWP) can include m LBT subbands. In this case, the base station can send DL indication information (e.g., a bitmap) to the terminal through one or more of the m LBT subbands, indicating whether downlink communication is being performed within the m LBT subbands. The DL indication information can be sent through one or more predefined LBT subbands among the m LBT subbands. The base station can send the DL indication information to the terminal through the LBT subband with the lowest index among the LBT subbands performing downlink communication within the BWP. Alternatively, the base station can send the DL indication information to the terminal through the LBT subband with the highest index among the LBT subbands performing downlink communication within the BWP. The terminal can receive the DL indication information within the LBT subbands and identify (one or more) LBT subbands performing downlink communication within the BWP based on the DL indication information.

[0192] The base station can send DL indication information (e.g., a bitmap) to the terminal, indicating whether downlink communication is to be performed within one or more of the m LBT subbands included in the BWP, through one or more predefined LBT subbands from the m LBT subbands. The one or more LBT subbands used to send the DL indication information can be indicated by DCI. The terminal can receive the DL indication information through one or more LBT subbands indicated by the DCI received from the base station and identify (one or more) LBT subbands within the BWP that are performing downlink communication based on the DL indication information.

[0193] exist Figure 12 In the exemplary embodiment shown, the base station can send DL indication information to the terminal via a time slot #n+2 whose start time point of the COT or downlink burst does not belong to it. The DL indication information can indicate whether downlink communication is performed in each LBT subband. DL indication information sent via LBT subbands #1 and / or #2 in time slot #n+2 can indicate whether downlink communication is performed in LBT subbands #1 and #2. Alternatively, DL indication information sent via LBT subbands #1 and / or #2 in time slot #n+2 can indicate whether downlink communication is performed in LBT subbands #1 through #4. The DL indication information (e.g., a bitmap) can be configured as a field in the DCI (e.g., the same field).

[0194] The terminal can identify whether to perform downlink communication in all LBT subbands included in the BWP based on DL indication information received through one or more LBT subbands within the BWP. The terminal can identify (one or more) LBT subbands that do not perform downlink communication based on the DL indication information, and can choose not to perform downlink monitoring operations in the identified (one or more) LBT subbands.

[0195] The base station can periodically transmit DL indication information (e.g., bitmaps). DL indication information (e.g., bitmaps) can be periodically transmitted via DCI. DL indication information can be periodically transmitted within COT. The terminal can periodically perform monitoring operations to receive DL indication information within the COT configured by the base station. The base station can notify the terminal of the monitoring operation configuration information (e.g., monitoring periodicity, monitoring interval). The terminal can periodically perform monitoring operations on the DCI including DL indication information based on the monitoring operation configuration information received from the base station. The terminal can receive DL indication information from the base station and, based on the DL indication information, identify whether to perform downlink communication in the LBT subband within the BWP.

[0196] The terminal may perform downlink monitoring operations in one or more LBT subbands identified as performing downlink communication (one or more) and may not perform downlink monitoring operations in one or more LBT subbands identified as not performing downlink communication (one or more)

[0197] At the same time, Figure 12 In the exemplary embodiment shown, the terminal can perform a DMRS detection operation (e.g., PDCCH DMRS) in time slot #n to estimate the BWP (e.g., LBT subband). The terminal can perform the DMRS detection operation in LBT subbands #1 to #4 within the active BWP. The terminal can detect DMRS in LBT subbands #1 and #2 of time slot #n, and may not detect DMRS in LBT subbands #3 and #4 of time slot #n. The terminal can perform a group common control channel detection operation in LBT subbands #1 and #2 where DMRS is successfully detected. Here, the group common control channel may include resource allocation information (e.g., resource structure indicator).

[0198] The terminal can obtain resource allocation information from the group common control channel (TCC). Based on this information, it can determine LBT subbands #1 and #2 for downlink communication on the frequency axis and time slots #n to #n+2 for downlink communication on the time axis. Therefore, the terminal can perform downlink monitoring operations in LBT subbands #1 and #2 in time slots #n to #n+2. Alternatively, the terminal may choose not to perform DMRS detection operations in time slots #n+1 to #n+2 to estimate the BWP (e.g., LBT subbands).

[0199] The base station can configure one or more LBT subbands within a BWP as the primary LBT subband. The base station can send the primary LBT subband configuration information to the terminal using one or more of higher-layer signaling, MAC CE, and DCI. The primary LBT subband can be predefined. A group common control channel can be configured within the primary LBT subband.

[0200] Figure 13 This is a conceptual diagram illustrating a second exemplary embodiment of a communication method using LBT subbands in a communication system.

[0201] refer to Figure 13 A Base Station Width (BWP) can include four Low-Level Band (LBT) subbands. The BWP width can be X MHz, and the width of each LBT subband can be Y MHz. One or more LBT subbands can be configured as the primary LBT subband. The primary LBT subband can be predefined. The base station can send DL indication information to the terminal, indicating whether to perform downlink communication in the primary LBT subband. When the primary LBT subband is LBT subband #1, the base station can send DL indication information through LBT subband #1. A group common control channel can be configured in LBT subband #1 (i.e., the primary LBT subband). The base station can send downlink transmission bandwidth information to the terminal through the group common control channel of LBT subband #1 (i.e., the primary LBT subband).

[0202] When a base station performs downlink communication in LBT subbands #1 and #2, DL indication information transmitted through LBT subband #1 (e.g., the main LBT subband) can indicate whether downlink communication is performed in LBT subbands #1 and #2. The base station can use the group common control channel to send downlink transmission bandwidth information to the terminal. The terminal can obtain downlink bandwidth information through LBT subband #1 (e.g., the main LBT subband). The terminal can perform downlink monitoring operations in LBT subband #1 (e.g., the main LBT subband) within the BWP. The terminal can perform DMRS detection operations in LBT subband #1 to detect downlink signals and / or channels. The terminal can perform group common control channel detection operations in LBT subband #1. The terminal can perform demodulation and decoding operations on the group common control channel of LBT subband #1, thereby identifying the frequency resources (e.g., one or more LBT subbands) for downlink communication within the BWP.

[0203] The following exemplary embodiments describe a method for detecting the PDCCH in an LBT subband when the LBT subband within a BWP, carrier, or cell is variably configured. The base station can configure the size of the CORESET frequency resources within the unlicensed band of the BWP (or carrier, cell) to be the same as the width of the BWP (or carrier, cell). Figure 13In the exemplary embodiment shown, when the width of the BWP is X MHz, the size of the CORESET on the frequency axis can be configured to X MHz. The CORESET can be configured in a frequency region excluding the guard band between LBT subbands within the BWP.

[0204] The base station can perform downlink communication in LBT subbands #1 and #2 based on the result of LBT operation, and may choose not to perform downlink communication in LBT subbands #3 and #4. The base station can configure control and data channels based on one or more LBT subbands(s) where downlink communication is performed, and can use these control and data channels to perform downlink communication. Control and data channels can be configured regardless of the CORESET configured via higher-layer signaling.

[0205] The size of the CORESET on the frequency axis can be the same as the width of the BWP. Alternatively, the frequency resources of the CORESET can be frequency resources that are not included in the guard bands (e.g., in-carrier guard bands) between LBT subbands within the BWP. In this case, downlink communication can be performed in one or more LBT subbands within the BWP. The frequency resources of the CORESET can be limited to the frequency resources used for performing downlink communication, and downlink communication can be performed based on the corresponding CORESET.

[0206] The frequency domain configuration information of a CORESET can be indicated using a bitmap. One of the bits included in this bitmap can indicate N RBs in the frequency domain. N can be an integer equal to or greater than 1. The CORESET can be configured in the frequency resources indicated by the bitmap. The first bit of the bitmap can indicate N RBs. The N RBs indicated by the first bit of the bitmap can be the starting RB of a BWP and (N-1) consecutive RBs from the starting RB. The starting RB can be the starting common resource block (CRB). The order of the RBs indicated by the bits of the bitmap can be ascending or descending. For example, the first bit of the bitmap can indicate RB#0 to RB#N-1, while the second bit of the bitmap can indicate RB#N to RB#2N-1. The base station can send the frequency domain configuration information of the CORESET (e.g., information indicating the frequency resources configured for the CORESET) to the terminal. The terminal can receive the configuration information of the CORESET from the base station and identify the frequency resources of the CORESET based on the received configuration information.

[0207] The base station can configure an offset for the frequency resources indicating the CORESET. For example, the base station can configure any value from 0 to N-1 as the offset. N can be an integer equal to or greater than 1. The offset can be an offset used to map between the bitmap indicating the frequency domain configuration information of the CORESET and the RB indexes within the BWP. When the offset is K and the Mth bit of the bitmap indicates RB#(M-1)×N to RB#M×N, the CORESET can be mapped to RB#(M-1)×N+K to RB#M×N+K in the frequency domain. Each of K and M can be an integer equal to or greater than 1, and N can be the number of RBs indicated by a bit of the bitmap.

[0208] The size of the CORESET in the frequency domain can be the same as the width of the BWP. Alternatively, the size of the CORESET in the frequency domain can be the same as the size of the frequency resources excluding the guard band between LBT subbands within the BWP. Downlink communication can be performed through one or more LBT subbands within the BWP. The terminal can identify one or more LBT subbands(s) performing downlink communication by performing detection operations on the DMRS (e.g., PDCCH DMRS) or downlink control channel. The terminal can determine that the frequency resources of the CORESET are the same as the frequency resources performing downlink communication. The terminal can identify the frequency resources (e.g., LBT subbands) performing downlink communication based on the above methods and can perform downlink monitoring operations on the identified frequency resources.

[0209] exist Figure 13 In the exemplary embodiment shown, the terminal can determine whether to perform downlink communication in LBT subbands #1 and #2 by performing a DMRS detection operation. Alternatively, the terminal can determine whether to perform downlink communication in LBT subbands #1 and #2 based on information received from the base station (e.g., DL indication information). The terminal can assume that the frequency resources of CORESET are limited to LBT subbands #1 and #2. Therefore, the terminal can perform PDCCH monitoring operations in LBT subbands #1 and #2.

[0210] The frequency resources of CORESET can be interpreted differently depending on the time slot location. Base stations and terminals may consider the frequency resources of CORESET to be equal to one LBT subband in the first time slot of a COT or downlink burst. Base stations and terminals may also consider the frequency resources of CORESET to be equal to the frequency resources used for downlink communication in one or more time slots other than the first time slot of a COT or downlink burst.

[0211] exist Figure 13In the exemplary embodiment shown, the base station and the terminal can assume that the width of the CORESET in time slot #n is equal to the width of the LBT subband. Therefore, the base station can transmit the PDCCH and can transmit the PDSCH scheduled by the PDCCH for each LBT subband. The terminal can receive the PDCCH by performing a PDCCH monitoring operation for each LBT subband and can receive the PDSCH scheduled by the PDCCH from the base station.

[0212] The base station and the terminal can assume that the frequency resources of CORESET in time slots #n+1 and #n+2 (excluding time slot #n) are equal to the frequency resources for performing downlink communication (e.g., LBT subbands #1 and #2). The base station can configure PDCCH in all LBT subbands #1 and #2. That is, the base station can transmit PDCCH in LBT subbands #1 and #2, and can also transmit PDSCH scheduled by the PDCCH. The terminal can receive PDCCH by performing PDCCH monitoring operations in all LBT subbands #1 and #2, and can receive PDSCH scheduled by the PDCCH from the base station.

[0213] The guard band between LBT subbands in the first time slot of a COT or downlink burst cannot be used for PDCCH and / or PDSCH. The guard band between LBT subbands in one or more time slots other than the first time slot of a COT or downlink burst can be used for PDCCH and / or PDSCH. The guard band may not exist in the remaining one or more time slots other than the first time slot of a COT or downlink burst.

[0214] Communication between the base station and the terminal can be performed using variable frequency bands within the BWP. In this case, the base station can use higher-layer signaling to configure a CORESET in the terminal with the same size as the LBT subband. The base station and the terminal can assume that the CORESET repeats in the frequency domain within the unlicensed band of the BWP, carrier, or cell. Figure 13 In the exemplary embodiment shown, the base station can configure a coreset with the same size as LBT subband #1 in the terminal using higher-layer signaling. The base station and the terminal can assume that the coreset configured by the higher-layer signaling is repeated in LBT subbands #1 to #4 within the BWP. The base station and the terminal can assume that the same coreset is configured in each LBT subband #1 to #4 within the BWP. The base station can configure a PDCCH in each LBT subband and can perform downlink communication based on the result of performing LBT operations. The terminal can receive downlink signals and / or channels by performing downlink monitoring operations in each LBT subband.

[0215] The base station can use higher-layer signaling to configure a CORESET in the terminal that is equal to or smaller than the LBT subband. The base station can configure a search space associated with the CORESET. The PDCCH timing for the search space can be repeated for each LBT subband. For example, there may be multiple PDCCH timings on a frequency axis. The base station can use higher-layer signaling to send the search space configuration information to the terminal. The search space configuration information may include the ID of the CORESET associated with the search space, information indicating one or more LBT subbands that will perform monitoring operations on the search space, etc.

[0216] The base station can configure CORESET X. The size of CORESET X in the frequency domain can be less than or equal to the size of the LBT subband. The base station can configure a search space Y associated with CORESET X. The configuration information of search space Y can include the ID of CORESET X associated with search space Y. In addition, the configuration information of search space Y can also include information indicating one or more LBT subbands for performing PDCCH monitoring operations based on the characteristics of CORESET X and search space Y. PDCCH monitoring operations can be performed in one or more LBT subbands. The information indicating one or more LBT subbands for performing PDCCH monitoring operations can be the index of the corresponding one or more LBT subbands. Alternatively, the information indicating one or more LBT subbands for performing PDCCH monitoring operations can be a bitmap. The one or more LBT subbands for performing PDCCH monitoring operations can be one or more LBT subbands configured in BWP, carrier, or cell.

[0217] The terminal can perform PDCCH monitoring operations using the configuration information of CORESET and search space. The terminal can perform PDCCH monitoring operations in one or more LBT subbands indicated by the base station. During PDCCH monitoring, the characteristics of CORESET can be the same in one or more LBT subbands, except for the frequency resources used to perform the PDCCH monitoring operation. The characteristics of the search space can also be the same in one or more LBT subbands during PDCCH monitoring.

[0218] The downlink signal and / or channel configuration can be modified based on the results of LBT operations in the LBT subbands within the BWP. The downlink signal and / or channel configuration when LBT operations are successful in all LBT subbands within the BWP can differ from the configuration when LBT operations are successful in only some LBT subbands within the BWP. When LBT operations are successful in all LBT subbands within the BWP, PDSCH can be configured in the BWP even without guard bands between LBT subbands.

[0219] Figure 14 This is a conceptual diagram illustrating a third exemplary embodiment of a communication method using LBT subbands in a communication system.

[0220] refer to Figure 14 LBT operations can succeed in all LBT subbands within the BWP. In this case, PDSCH can be configured in all frequency resources belonging to the BWP. There may be no guard band between LBT subbands in the time slot(s) containing the PDSCH. For example, the PDSCH can be mapped to a guard band between LBT subbands. The base station can send DL indication information indicating that downlink communication is performed in all LBT subbands within the BWP. The base station can use the PDSCH to send downlink signals and / or channels to the terminal.

[0221] The terminal can receive DL indication information from the base station and determine, based on the DL indication information, that downlink communication is performed in all LBT subbands within the BWP. In this case, the terminal can assume that there is no guard band between the LBT subbands in the time slot(s) where the PDSCH(s) configured within the BWP reside. That is, the terminal can assume that the PDSCH(s) are configured continuously within the BWP. Based on the above assumption, the terminal can determine the size of the transport block (TB) and perform rate matching operations for downlink communication.

[0222] When all LBT operations in all LBT subbands within the BWP are successful, guard bands may be absent in all (one or more) time slots included in the COT, except for the first time slot or the first part of the time slot configured with PDSCH.

[0223] Figure 15 This is a conceptual diagram illustrating a fourth exemplary embodiment of a communication method using LBT subbands in a communication system.

[0224] refer to Figure 15 LBT operation may succeed in all LBT subbands within the BWP. In this case, PDSCH can be configured within the LBT subband of the first time slot (e.g., time slot #n) of the COT. For example, PDSCH may not be configured in the guard band(s) between LBT subbands. Guard band(s) may exist between the LBT subbands in the first time slot (e.g., time slot #n) of the COT. Here, the first time slot may be a partial time slot, and the size of the partial time slot may be smaller than the size of a single time slot.

[0225] In all time slots included in the COT except for the first time slot (e.g., time slots #n+1 and #n+2), the PDSCH can be configured in all frequency resources belonging to the BWP. For example, the PDSCH can be configured in the guard band between LBT sub-bands. The guard band between LBT sub-bands may not exist in time slots after the first time slot in the COT (e.g., time slots #n+1 and #n+2).

[0226] When LBT operations are successful in all LBT subbands within the BWP, the base station can configure guard bands between LBT subbands in the first time slot or the first part of the time slot in the COT, and can choose not to configure guard bands between LBT subbands in the remaining (one or more) time slots included in the COT, excluding the first time slot or the first part of the time slot. Therefore, in the first time slot or the first part of the time slot in the COT, PDSCH can be configured in all frequency resources belonging to the BWP, excluding the guard bands between LBT subbands. In the time slots included in the COT, excluding the first time slot or the first part of the time slot, PDSCH can be configured in all frequency resources belonging to the BWP.

[0227] The base station can send DL indication information indicating that downlink communication is performed in all LBT subbands within the BWP. The terminal can receive the DL indication information from the base station and determine, based on the DL indication information, that downlink communication is performed in all LBT subbands within the BWP. The terminal can determine that there are one or more guard bands between LBT subbands in the first time slot or the first part of the time slot of the COT. That is, the terminal can assume that the PDSCH is not mapped to guard bands between LBT subbands in the first time slot or the first part of the time slot of the COT. In addition, the terminal can determine that there are no guard bands between LBT subbands in one or more time slots other than the first time slot or the first part of the time slot included in the COT. That is, the terminal can determine that the PDSCH is mapped to all frequency resources belonging to the BWP in the remaining one or more time slots other than the first time slot or the first part of the time slot included in the COT.

[0228] The terminal can determine the size of the TB by considering the guard bands (one or more) between LBT subbands in the first time slot or the first part of the time slot of the COT, and can perform rate matching operations for downlink communication. The terminal can also determine the size of the TB without considering the guard bands (one or more) between LBT subbands in the time slots (other than the first time slot or the first part of the time slot) included in the COT, and can perform rate matching operations for downlink communication.

[0229] When LBT operation fails in one or more LBT subbands belonging to BWP, a guard band can be configured between LBT subbands (e.g., LBT subbands where LBT operation was successful). In this case, PDSCH can be mapped to the remaining frequency resources of the LBT subbands where LBT operation was successful, excluding the guard band.

[0230] exist Figure 12 In the exemplary embodiment shown, LBT operations may succeed in LBT subbands #1 and #2, while LBT operations may fail in LBT subbands #3 and #4. In this case, downlink communication can be performed in LBT subbands #1 and #2. PDSCH can be mapped to the remaining frequency resources in LBT subbands #1 and #2, excluding the guard band. That is, a guard band may exist between LBT subbands #1 and #2, and PDSCH can be configured in frequency resources other than the guard band. When LBT operations succeed in LBT subbands #1 and #2, the base station can configure a guard band between LBT subbands #1 and #2 and can use frequency resources other than the guard band between LBT subbands #1 and #2 to transmit PDSCH.

[0231] The base station can send DL indication information indicating downlink communication to be performed in LBT subbands #1 and #2 within the BWP. The terminal can receive the DL indication information from the base station and determine, based on the DL indication information, that downlink communication is to be performed in LBT subbands #1 and #2 within the BWP. In this case, the terminal can determine that a guard band exists between LBT subbands #1 and #2, and can determine that a PDSCH is configured in frequency resources other than the guard band between LBT subbands #1 and #2. The terminal can consider the guard band between LBT subbands #1 and #2 to determine the size of the TB and perform rate matching operations.

[0232] The exemplary embodiments of this disclosure can be implemented as program instructions executable by various computers and recorded on a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, or combinations thereof. The program instructions recorded on the computer-readable medium may be specifically designed and configured for this disclosure, or may be well-known and available to those skilled in the art of computer software.

[0233] Examples of computer-readable media may include hardware devices such as ROM, RAM, and flash memory, specifically configured to store and execute program instructions. Examples of program instructions include, for example, machine code generated by a compiler, and high-level language code executable by a computer using an interpreter. The exemplary hardware devices described above may be configured to operate as at least one software module to perform embodiments of this disclosure, and vice versa.

[0234] Although embodiments of the present disclosure and their advantages have been described in detail, it should be understood that various changes, substitutions and modifications can be made to this document without departing from the scope of the disclosure.

Claims

1. A method for operating a terminal in a communication system, the method comprising: Receive first configuration information of one or more guard bands in the unlicensed band from the base station; The one or more protection bands configured in the unauthorized bands are identified based on the first configuration information; as well as Based on the identification of the first Listen Before Talk (LBT) sub-band and the second LBT sub-band configured in the unauthorized band using the one or more guard bands, Each of the one or more guard bands is located between the first LBT sub-band and the second LBT sub-band, and the channel state information reference signal (CSI-RS) resources are configured in all the first LBT sub-bands and the second LBT sub-bands. When downlink communication is performed in all first LBT subbands and second LBT subbands, measurement operations are performed on the CSI-RS in all first LBT subbands and second LBT subbands, and Even if no downlink communication is performed in at least one of the first LBT subband and the second LBT subband, the measurement operation is not performed on the CSI-RS in all of the first LBT subband and the second LBT subband.

2. The operating method according to claim 1, wherein, The first configuration information includes the start protection RB (G-RB) index and the end G-RB index of each of the one or more protection strips, and when N protection strips are configured, the number of pairs of the start G-RB index and the end G-RB index included in the first configuration information is N, where N is an integer greater than or equal to 1.

3. The operating method according to claim 1, wherein: The starting LBT subband in the first LBT subband and the second LBT subband includes the resource block (RB) from the starting RB of the unlicensed band to the resource block (RB) immediately preceding the starting G-RB of the starting guard band in the one or more guard bands, and the ending LBT subband in the first LBT subband and the second LBT subband includes the RB after the ending G-RB of the ending guard band in the one or more guard bands to the ending RB of the unlicensed band; and The starting LBT subband is the LBT subband with the lowest frequency resources among the first LBT subband and the second LBT subband, while the ending LBT subband is the LBT subband with the highest frequency resources among the first LBT subband and the second LBT subband. The starting guard band is the guard band with the lowest frequency resources among the one or more guard bands, while the ending guard band is the guard band with the highest frequency resources among the one or more guard bands.

4. The operating method according to claim 1 further includes: The base station receives second configuration information indicating whether to perform downlink communication in each of the first LBT subband and the second LBT subband.

5. The operating method according to claim 4, wherein, The second configuration information is a bitmap, and the bitmap is included in the downlink control information (DCI).

6. A method for operating a base station in a communication system, the method comprising: Configure one or more protective bands for unauthorized bands; Send the first configuration information of the one or more protection bands to the terminal; as well as The device communicates with the terminal by using one or more Listen-Before-Talk (LBT) subbands in the first LBT subband and the second LBT subband, which are configured in frequency resources other than the one or more guard bands in the unlicensed band. Specifically, based on the first configuration information, the number, location, and size of multiple LBT subbands, including the first LBT subband and the second LBT subband, are determined, and the channel state information reference signal (CSI-RS) resources are allocated in all the first LBT subbands and the second LBT subbands. When downlink communication is performed in all first LBT subbands and second LBT subbands, measurement operations are performed on the CSI-RS in all first LBT subbands and second LBT subbands, and Even when no downlink communication is performed in at least one of the LBT subband and the first and second LBT subbands, the terminal does not receive measurement results of the CSI-RS in all the first and second LBT subbands.

7. The operating method according to claim 6, wherein, The first configuration information includes the starting protection RB (G-RB) index and the ending G-RB index of each of the one or more protection strips. When N protection strips are configured, the number of pairs of starting G-RB indices and ending G-RB indices included in the first configuration information is N, where N is an integer equal to or greater than 1.

8. The method of operation according to claim 6 further includes sending second configuration information to the terminal indicating whether to perform downlink communication in the plurality of LBT subbands, wherein the second configuration information is a bitmap and the bitmap is included in downlink control information (DCI).

9. The method of operation according to claim 6 further includes sending to the terminal third configuration information of a control resource set (CORESET) configured in the unlicensed band and fourth configuration information of a search space configured in the unlicensed band, wherein the third configuration information is applied together to the plurality of LBT subbands, and wherein the number of RBs of the CORESET is set to be equal to or less than the number of RBs belonging to one LBT subband.

10. The operating method according to claim 9, wherein, The third configuration information includes an offset indicating the position of the CORESET on the frequency axis, and the offset indicates the deviation between the starting RB of the unlicensed band and the starting RB of the CORESET.

11. The operating method according to claim 9, wherein, The search space associated with CORESET is repeated across the plurality of LBT subbands, and the fourth configuration information includes a field indicating whether the search space is configured in each of the plurality of LBT subbands.

12. A terminal in a communication system, the terminal comprising a processor and a memory storing at least one instruction executable by the processor, wherein the at least one instruction causes the processor to: Receive first configuration information of one or more guard bands in the unlicensed band from the base station; The one or more protection bands configured in the unauthorized bands are identified based on the first configuration information; Based on the one or more protection bands, identify the first Listen Before Talk (LBT) sub-band and the second LBT sub-band configured in the unlicensed band, and The base station receives second configuration information of the control resource set (CORESET) configured in the unlicensed band and third configuration information of the search space configured in the unlicensed band. in, The second configuration information is applied to both the first LBT subband and the second LBT subband, wherein the number of RBs with CORESET set is equal to or less than the number of RBs belonging to one LBT subband, and the Channel State Information Reference Signal (CSI-RS) resources are configured in all the first LBT subbands and the second LBT subbands. When downlink communication is performed in all first LBT subbands and second LBT subbands, measurement operations are performed on the CSI-RS in all first LBT subbands and second LBT subbands, and Even if no downlink communication is performed in at least one of the first LBT subband and the second LBT subband, no measurement operation is performed on the CSI-RS in any of the first LBT subband and the second LBT subband.

13. The terminal according to claim 12, wherein, The first configuration information includes the starting protection RB (G-RB) index and the ending G-RB index for each of the one or more protection bands; When N protection bands are configured, the number of pairs of the start G-RB index and the end G-RB index included in the first configuration information is N, where N is an integer greater than or equal to 1.

14. The terminal according to claim 12, wherein, The second configuration information includes an offset indicating the position of the CORESET on the frequency axis, and the offset indicates the deviation between the starting RB of the unlicensed band and the starting RB of the CORESET.

15. The terminal according to claim 12, wherein, The search space associated with the CORESET is repeated in the first LBT subband and the second LBT subband, and the third configuration information includes a field indicating whether the search space is configured in each LBT subband of the first LBT subband and the second LBT subband.

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