Method and apparatus for supporting partial-band full-duplex communication with synchronization signal block transmission

Abstract

The terminal method includes: identifying an SSB time interval for SSB reception or measurement and a general time interval other than the SSB time interval; receiving or measuring at least one SSB in the SSB time interval; and transmitting at least one uplink signal or receiving at least one downlink signal in the general time interval, and SBFD (subband full duplex) operation can be performed in the SSB time interval and the general time interval, or SBFD operation can be performed only in the general time interval without performing SBFD operation in the SSB time interval.

Description

[Technical Field]

[0001] The present invention relates to subband full-duplex communication, and more particularly to a method and apparatus for supporting subband full-duplex communication by taking into account the transmission of synchronization signal blocks. [Background technology]

[0002] Two-way communication (duplex) between communication nodes (e.g., a base station and a terminal) can be performed based on half-duplex or full-duplex. In full-duplex, communication nodes can perform transmission and reception simultaneously or at different times. Even in TDD systems (e.g., systems using TDD carriers, unpaired spectrum, etc.), communication nodes can perform transmission and reception within a common frequency range (e.g., a carrier commonly used for uplink and downlink transmission). When transmission and reception are performed simultaneously, the transmission signal may interfere with the reception signal. Therefore, self-interference cancellation technology may be required to perform full-duplex communication in TDD systems.

[0003] In Rel-18, the start of 5G-Advanced, research is underway on full-duplex communication methods to increase frequency efficiency, improve uplink performance, and reduce latency. More specifically, a base station can perform transmission and reception simultaneously, while a mobile station can only perform either transmission or reception at a given time. Research is also underway on sub-band full-duplex (SBFD) communication methods, in which the frequency resources for uplink and downlink resources are separated from each other during the time period during which simultaneous transmission of uplink and downlink signals between a mobile station and a base station is permitted.

[0004] Even when communication is performed using the SBFD scheme, the terminal may lack or have insufficient capabilities to remove cross-link interference compared to the base station. Furthermore, in the case of a terminal of a previous release (existing terminal, legacy UE) that does not support the SBFD scheme, the terminal may not have the capability to remove cross-link interference from the beginning. Therefore, an SBFD communication method that takes into account the transmission interval of SSB (synchronization signal block), which is one of the important downlink signals in the new radio (NR) communication system, is required. Summary of the Invention [Problem to be solved by the invention]

[0005] SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide a method and apparatus for supporting partial-band full-duplex communication in consideration of transmission of a synchronization signal block. [Means for solving the problem]

[0006] In a first embodiment of the present invention to solve the above problems, a method of a terminal includes: a step of identifying an SSB time interval for receiving or measuring an SSB (synchronization signal block) and a general time interval other than the SSB time interval; a step of receiving or measuring at least one SSB in the SSB time interval; and a step of transmitting at least one uplink signal or receiving at least one downlink signal in the general time interval, and a subband full duplex (SBFD) operation can be performed in the SSB time interval and the general time interval, or the SBFD operation can be performed only in the general time interval without being performed in the SSB time interval.

[0007] The SSB time interval may be determined by an SSB burst set predefined by a technical standard, or may be determined as the position or interval at which the SSB(s) are actually transmitted within the SMTC window or SSB burst set, as determined based on RMSI (remaining system information) and / or UE-specific RRC signaling received from the base station.

[0008] When SBFD operation is performed in the SSB time interval, a first guard band for the SBFD operation applied to the SSB time interval and a second guard band for the SBFD operation applied to the general time interval can be set separately.

[0009] When SBFD operation is performed in the SSB time interval, the uplink transmission power for the SBFD operation applied to the SSB time interval and the uplink transmission power for the SBFD operation applied to the general time interval can be set separately.

[0010] The method may further include receiving from the base station a list including at least one Transmission Configuration Indicator (TCI) or SRS resource indicator (SRI) that is prohibited in the SSB time interval, and when SBFD operation is performed in the SSB time interval, the terminal may not perform uplink transmission to which the at least one TCI or SRI is applied during the SSB time interval.

[0011] The SSB time interval is divided into a CD-SSB time interval in which cell-defining (CD)-SSB(s) are transmitted and / or an NCD-SSB time interval in which non-cell-defining (NCD)-SSB(s) are transmitted. When an SBFD operation is performed in the SSB time interval, a first guard band for the SBFD operation applied to the CD-SSB time interval and a second guard band for the SBFD operation applied to the NCD-SSB time interval may be set separately, or an uplink transmission power for the SBFD operation applied to the CD-SSB time interval and an uplink transmission power for the SBFD operation applied to the NCD-SSB time interval may be set separately.

[0012] In a second embodiment of the present invention to solve the above problems, a method for a terminal may include: receiving configuration information for an SSB time interval for SSB (synchronization signal block) reception or measurement from a base station; receiving configuration information for SBFD (subband full duplex) operation from the base station; determining whether to perform the SBFD operation in the SSB time interval; and, if it is determined to perform the SBFD operation in the SSB time interval, performing the SBFD operation in the SSB time interval.

[0013] The SSB time interval setting information may be received as SSB measurement window setting information or may be received based on the SSB measurement window setting information and RMSI (remaining system information) and / or UE-specific RRC signaling, and the SSB time interval may be determined by the SSB measurement window indicated by the SSB measurement window setting information or may be determined to be the position(s) or interval(s) at which SSB(s) are actually transmitted within the SSB measurement window, as indicated by the RMSI and / or UE-specific RRC signaling.

[0014] The method may further include performing the SBFD operation in a general time interval other than the SSB time interval.

[0015] When the SBFD operation is performed in the SSB time interval, first guard band(s) may be set around uplink resources belonging to the frequency domain for performing the SBFD operation within the SSB time interval.

[0016] The bandwidth of the second guard band(s) set around uplink resources belonging to the frequency domain for performing the SBFD operation in a general time interval that does not overlap with the bandwidth of the first guard band(s) and the SSB time interval can be set separately.

[0017] If uplink transmission is scheduled through uplink resources including the first guard band(s), the terminal can either abandon the uplink transmission or perform the uplink transmission using the uplink resources excluding the resources belonging to the first guard band(s).

[0018] When the uplink transmission is performed using resources other than the resources belonging to the first guard band(s) among the uplink resources, the terminal may perform puncturing or rate-matching on the uplink transmission data mapped to the resources belonging to the first guard band(s).

[0019] When the SBFD operation is performed in the SSB time interval, the transmit power applied to the uplink resources belonging to the frequency domain for performing the SBFD operation within the SSB time interval and the transmit power applied to the uplink resources belonging to the frequency domain for performing the SBFD operation in a general time interval that does not overlap with the SSB time interval can be set separately.

[0020] The method may further include receiving from the base station a list including at least one Transmission Configuration Indicator (TCI) or SRS resource indicator (SRI) that is prohibited in the SSB time interval, and when SBFD operation is performed in the SSB time interval, the terminal may not perform uplink transmission to which the at least one TCI or SRI is applied during the SSB time interval.

[0021] The SSB time interval is divided into a CD-SSB time interval in which cell-defining (CD)-SSB(s) are transmitted and / or an NCD-SSB time interval in which non-cell-defining (NCD)-SSB(s) are transmitted. When an SBFD operation is performed in the SSB time interval, a first guard band for the SBFD operation applied to the CD-SSB time interval and a second guard band for the SBFD operation applied to the NCD-SSB time interval may be set separately, or an uplink transmission power for the SBFD operation applied to the CD-SSB time interval and an uplink transmission power for the SBFD operation applied to the NCD-SSB time interval may be set separately.

[0022] In a third embodiment of the present invention to solve the above problems, a method of a terminal may include: receiving configuration information for a first SSB measurement window from a base station; receiving configuration information regarding SBFD (subband full duplex) operation from the base station; receiving configuration information for a second SSB measurement window from the base station; performing a measurement operation on SSB(s) in a first SSB time interval belonging to the second SSB measurement window; and performing the SBFD operation in a time interval belonging to the first SSB measurement window but not belonging to the second SSB measurement window.

[0023] The first SSB measurement window configuration information and the second SSB measurement window configuration information may be SSB-based RRM Measurement Timing Configuration (SMTC) window configuration information, respectively.

[0024] The method may further include a step of determining whether to perform the SBFD operation in the first SSB time interval, and the step of determining whether to perform the SBFD operation in the first SSB time interval may include: receiving information from the base station regarding the position(s) at which SSB(s) are actually transmitted among the SSB transmission positions within the first SSB time interval; determining to perform the SBFD operation at positions excluding the position(s) at which SSB(s) are actually transmitted among the SSB transmission positions within the first SSB time interval; and, if it is determined to perform the SBFD operation in the first SSB time interval, performing the SBFD operation in the first SSB time interval.

[0025] Information on the position(s) where the SSB(s) are actually transmitted among the SSB transmittable positions within the first SSB time interval may be the ssb-PositionsInBurst parameter received from the base station through RMSI (remaining system information) and / or terminal-specific RRC (radio resource control) signaling. [Effects of the Invention]

[0026] According to an embodiment of the present invention, SBFD communication can be performed taking into account the transmission of SSB. Therefore, crosslink interference with reception of SSB, which is an important downlink signal, performed by other terminals can be reduced, and resource efficiency can be maintained through SBFD operation. Therefore, the performance of the overall communication system can be improved. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a conceptual diagram illustrating a first embodiment of a communication system.

[0028] [Figure 2] 1 is a block diagram illustrating a first embodiment of a communication node that constitutes a communication system.

[0029] [Figure 3] FIG. 1 is a conceptual diagram illustrating a first embodiment of a Type 1 frame structure.

[0030] [Figure 4] FIG. 1 is a conceptual diagram illustrating a first embodiment of a type 2 frame structure.

[0031] [Figure 5] 1 is a conceptual diagram illustrating a first embodiment of a method for transmitting SS / PBCH blocks in a communication system.

[0032] [Figure 6] FIG. 1 is a conceptual diagram illustrating a first embodiment of an SS / PBCH block in a communication system.

[0033] [Figure 7] FIG. 2 is a conceptual diagram illustrating a second embodiment of a method for transmitting SS / PBCH blocks in a communication system.

[0034] [Figure 8] 1 is a conceptual diagram for explaining the time domain transmission position of SSB according to subcarrier spacing and L.

[0035] [Figure 9] 1 is a conceptual diagram illustrating an example of notifying the actual transmission position of SSB through RMSI in the FR2 band.

[0036] [Figure 10a] FIG. 1 is a conceptual diagram illustrating RMSI CORESET mapping pattern #1 in a communication system. [Figure 10b]FIG. 10 is a conceptual diagram illustrating RMSI CORESET mapping pattern #2 in a communication system. [Figure 10c] FIG. 10 is a conceptual diagram illustrating RMSI CORESET mapping pattern #3 in a communication system.

[0037] [Figure 11a] 10 is a diagram illustrating various configuration examples of Type 0 CSS slots corresponding to SSB indexes. [Figure 11b] 10 is a diagram illustrating various configuration examples of Type 0 CSS slots corresponding to SSB indexes. [Figure 11c] 10 is a diagram illustrating various configuration examples of Type 0 CSS slots corresponding to SSB indexes.

[0038] [Figure 12] FIG. 10 is a conceptual diagram illustrating a first embodiment of slot configuration in which a PSFCH is configured.

[0039] [Figure 13] FIG. 1 is a conceptual diagram illustrating a first embodiment of a PSFCH for ACK / NACK transmission.

[0040] [Figure 14] FIG. 1 is a conceptual diagram illustrating an embodiment of a method for multiplexing a control channel and a data channel in sidelink communication.

[0041] [Figure 15] FIG. 2 is a conceptual diagram illustrating a first embodiment of a resource selection operation.

[0042] [Figure 16] FIG. 2 is a conceptual diagram illustrating a first embodiment of a resource re-selection operation.

[0043] [Figure 17] FIG. 1 is a conceptual diagram for explaining full-duplex communication in the same band.

[0044] [Figure 18] 1 is a conceptual diagram illustrating an embodiment for explaining a method for multiplexing uplink and downlink signals in full-duplex communication.

[0045] [Figure 19] FIG. 1 is a conceptual diagram illustrating the configuration of a frequency domain for SBFD operation according to one embodiment of the present invention.

[0046] [Figure 20] 10 is a conceptual diagram illustrating a case where guard bands of different widths are set in an SSB time period and a general time period according to an embodiment of the present invention. FIG.

[0047] [Figure 21] 1 is a flowchart illustrating a method for performing SBFD operation in consideration of SSB transmission according to an embodiment of the present invention.

[0048] [Figure 22] 10 is a flowchart illustrating a method for performing SBFD operation in consideration of SSB transmission according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0049] While the present invention can be modified in various ways and has various embodiments, specific embodiments will be illustrated in the drawings and described in detail, but it should be understood that this is not intended to limit the present invention to the specific embodiments, and that the present invention includes all modifications, equivalents, and alternatives that fall within the spirit and technical scope of the present invention.

[0050] Terms such as "first," "second," etc. may be used to describe various components, but the components should not be limited by these terms. These terms are used only to distinguish one component from another. For example, a first component may be designated as a second component, and similarly, a second component may be designated as a first component, without departing from the scope of the present invention. The term "and / or" includes a combination of multiple related listed items or any of multiple related listed items.

[0051] In the examples of this application, "at least one of A and B" may mean "at least one of A or B" or "at least one of a combination of one or more of A and B." Also, in the examples of this application, "one or more of A and B" may mean "one or more of A or B" or "one or more of a combination of one or more of A and B."

[0052] In the embodiments of the present application, (re)transmission may mean "transmission," "retransmission," or "transmission and retransmission," (re)configuration may mean "configuration," "reconfiguration," or "configuration and reconfiguration," (re)connection may mean "connection," "reconnection," or "connection and reconnection," and (re)connection may mean "connection," "reconnection," or "connection and reconnection."

[0053] When a component is said to be "coupled" or "connected" to another component, it should be understood that it may be directly coupled or connected to the other component, but that there may be other components in between. Conversely, when a component is said to be "directly coupled" or "directly connected" to another component, it should be understood that there are no other components in between.

[0054] The terms used in this application are merely used to describe specific embodiments and are not intended to limit the present invention. The singular expressions include the plural expressions unless the context clearly dictates otherwise. In this application, the terms "comprise" or "have" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and should be understood not to preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0055] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms as defined in commonly used dictionaries should be interpreted to have a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense unless expressly defined in this application.

[0056] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In describing the present invention, the same reference numerals will be used to refer to the same components in the drawings in order to facilitate overall understanding, and duplicate descriptions of the same components will be omitted.

[0057] A communication system to which an embodiment of the present invention is applied will now be described. The communication system to which an embodiment of the present invention is applied is not limited to the content described below, and the embodiment of the present invention may be applied to various communication systems. Here, the term "communication system" may be used interchangeably with the term "communication network."

[0058] FIG. 1 is a conceptual diagram illustrating a first embodiment of a communication system.

[0059] 1, the communication system 100 may include a plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6. The communication system 100 may further include a core network (e.g., a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), and a mobility management entity (MME)). When the communication system 100 is a 5G communication system (e.g., a new radio (NR) system), the core network may include an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc.

[0060] The plurality of communication nodes 110 to 130 can support communication protocols (eg, LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.) defined in the 3GPP (3rd generation partnership project) standard. The plurality of communication nodes 110 to 130 may support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (Space Division Multiple Access) technology, etc. Each of the plurality of communication nodes may have the following structure.

[0061] FIG. 2 is a block diagram illustrating a first embodiment of a communication node that constitutes a communication system.

[0062] 2, a communication node 200 may include at least one processor 210, a memory 220, and a transceiver 230 that is connected to a network to perform communication. The communication node 200 may further include an input interface device 240, an output interface device 250, a storage device 260, etc. Each component included in the communication node 200 is connected to a bus 270 to perform communication.

[0063] However, each component included in the communication node 200 may be connected through a separate interface or separate bus centered around the processor 210, rather than through a common bus 270. For example, the processor 210 may be connected to at least one of the memory 220, the transceiver 230, the input interface device 240, the output interface device 250, and the storage device 260 through a dedicated interface.

[0064] The processor 210 can execute program commands stored in at least one of the memory 220 and the storage device 260. The processor 210 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. The memory 220 and the storage device 260 may each be composed of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 220 may be composed of at least one of a read-only memory (ROM) and a random access memory (RAM).

[0065] 1, the communication system 100 may include multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2, and multiple terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6. The first base station 110-1, the second base station 110-2, and the third base station 110-3 may each form a macro cell. The fourth base station 120-1 and the fifth base station 120-2 may each form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to the cell coverage of the first base station 110-1. The second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong within the cell coverage of the second base station 110-2. The fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 may belong within the cell coverage of the third base station 110-3. The first terminal 130-1 may belong within the cell coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong within the cell coverage of the fifth base station 120-2.

[0066] Here, the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be referred to as NodeBs (NBs), evolved NodeBs (eNBs), gNBs, advanced base stations (ABSs), high reliability-base stations (HR-BSs), base transceiver stations (BTSs), radio base stations, radio transceivers, access points, access nodes, radio access stations (RASs), mobile multihop relay-base stations (MMR-BSs), relay stations (RSs), advanced relay stations (ARSs), high reliability-relay stations (HR-RSs), home NodeBs (HNBs), home eNodeBs (HeNBs), road side units (RSUs), radio remote heads (RRHs), transmission points (TPs), transmission and reception points (TRPs), etc.

[0067] The multiple terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 may each be referred to as a UE (user equipment), TE (terminal equipment), AMS (advanced mobile station), HR-MS (high reliability-mobile station), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, OBU (on board unit), etc.

[0068] Meanwhile, the base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may operate in different frequency bands or the same frequency band. The base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to each other via an ideal backhaul link or a non-ideal backhaul link, and may exchange information via the ideal backhaul link or the non-ideal backhaul link. The base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to the core network via an ideal backhaul link or a non-ideal backhaul link. Each of the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can transmit signals received from the core network to the corresponding terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6, and can transmit signals received from the corresponding terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 to the core network.

[0069] In addition, the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can each support MIMO transmission (e.g., single user (SU)-MIMO, multi user (MU)-MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in unlicensed bands, device to device communication (D2D) (or proximity services (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), etc. Here, the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 may perform operations corresponding to and supported by base stations 110-1, 110-2, 110-3, 120-1, and 120-2, respectively. For example, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 based on the SU-MIMO scheme, and the fourth terminal 130-4 may receive a signal from the second base station 110-2 based on the SU-MIMO scheme. Alternatively, the second base station 110-2 can transmit signals to the fourth terminal 130-4 and the fifth terminal 130-5 based on the MU-MIMO scheme, and the fourth terminal 130-4 and the fifth terminal 130-5 can each receive signals from the second base station 110-2 using the MU-MIMO scheme.

[0070] The first base station 110-1, the second base station 110-2, and the third base station 110-3 can each transmit signals to the fourth terminal 130-4 based on the CoMP scheme, and the fourth terminal 130-4 can receive signals from the first base station 110-1, the second base station 110-2, and the third base station 110-3 based on the CoMP scheme. The multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can each transmit and receive signals to and from terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 within their own cell coverage based on the CA scheme. The first base station 110-1, the second base station 110-2, and the third base station 110-3 can each control D2D between the fourth terminal 130-4 and the fifth terminal 130-5, and the fourth terminal 130-4 and the fifth terminal 130-5 can perform D2D under the control of the second base station 110-2 and the third base station 110-3, respectively.

[0071] Meanwhile, a communication system can support three types of frame structures: Type 1 frame structure can be applied to an FDD (frequency division duplex) communication system, Type 2 frame structure can be applied to a TDD (time division duplex) communication system, and Type 3 frame structure can be applied to an unlicensed spectrum-based communication system (e.g., an LAA (licensed assisted access) communication system).

[0072] FIG. 3 is a conceptual diagram illustrating a first embodiment of a Type 1 frame structure.

[0073] 3, a radio frame 300 may include 10 subframes, and each subframe may include two slots. Therefore, the radio frame 300 may include 20 slots (e.g., slot #0, slot #1, slot #2, slot #3, ..., slot #18, slot #19). The length Tf of the radio frame 300 may be 10 milliseconds (ms), the length of a subframe may be 1 ms, and the slot length (Tslot) may be 0.5 ms. Here, Ts may indicate the sampling time and may be 1 / 30,720,000 seconds (s).

[0074] A slot may consist of multiple OFDM symbols in the time domain and multiple resource blocks (RBs) in the frequency domain. A resource block may consist of multiple subcarriers in the frequency domain. The number of OFDM symbols that make up a slot may vary depending on the configuration of the cyclic prefix (CP). CPs may be classified as normal CPs and extended CPs. When a normal CP is used, a slot may consist of seven OFDM symbols, in which case a subframe may consist of 14 OFDM symbols. When an extended CP is used, a slot may consist of six OFDM symbols, in which case a subframe may consist of 12 OFDM symbols.

[0075] FIG. 4 is a conceptual diagram illustrating a first embodiment of a Type 2 frame structure.

[0076] Referring to Figure 4, a radio frame 400 may include two half frames, each of which may include five subframes. Therefore, the radio frame 400 may include ten subframes. The length Tf of the radio frame 400 may be 10 ms. The length of a half frame may be 5 ms. The length of a subframe may be 1 ms. Here, Ts may be 1 / 30,720,000 s.

[0077] The radio frame 400 may include a downlink subframe, an uplink subframe, and a special subframe. Each of the downlink subframe and the uplink subframe may include two slots. The slot length (Tslot) may be 0.5 ms. Among the subframes included in the radio frame 400, subframe #1 and subframe #6 may each be a special subframe. For example, if the downlink-uplink switching period is 5 ms, the radio frame 400 may include two special subframes. Alternatively, if the downlink-uplink switching period is 10 ms, the radio frame 400 may include one special subframe. The special subframe may include a downlink pilot time slot (DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS).

[0078] The downlink pilot time slot can be considered as a downlink interval and can be used for a terminal's cell search, time and frequency synchronization acquisition, channel estimation, etc. The guard interval can be used to solve the problem of interference with uplink data transmission caused by downlink data reception delay. The guard interval can also include the time required for switching from a downlink data reception operation to an uplink data transmission operation. The uplink pilot time slot can be used for uplink channel estimation, time and frequency synchronization acquisition, etc. Transmission of a physical random access channel (PRACH) or a sounding reference signal (SRS) can be performed in the uplink pilot time slot.

[0079] The lengths of the downlink pilot time slot, guard interval, and uplink pilot time slot included in the special subframe may be variably adjusted as needed, and the number and locations of the downlink subframes, uplink subframes, and special subframes included in the radio frame 400 may be changed as needed.

[0080] In a communication system, a transmission time interval (TTI) may be a basic time unit for transmitting coded data through a physical layer. A short TTI may be used in a communication system to support low latency requirements. The length of the short TTI may be less than 1 ms. An existing TTI having a length of 1 ms may be referred to as a base TTI or regular TTI. That is, the base TTI may consist of one subframe. To support transmission in base TTI units, signals and channels may be configured in subframe units. For example, a cell-specific reference signal (CRS), a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), a physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), etc. may exist in each subframe.

[0081] On the other hand, synchronization signals (e.g., PSS (primary synchronization signal), SSS (secondary synchronization signal)) can exist every 5 subframes, and PBCH (physical broadcast channel) can exist every 10 subframes. Radio frames can be distinguished by SFN, which can be used to define the transmission of signals whose transmission period is longer than one radio frame (e.g., paging signals, reference signals for channel estimation, signals indicating channel state information, etc.). The period of SFN can be 1024.

[0082] In an LTE system, the PBCH may be a physical layer channel used to transmit system information (e.g., a master information block (MIB)). The PBCH may be transmitted every 10 subframes. That is, the transmission period of the PBCH may be 10 ms, and the PBCH may be transmitted once per radio frame. The same MIB may be transmitted for four consecutive radio frames, and after four consecutive radio frames, the MIB may be changed depending on the status of the LTE system. The transmission period of the same MIB may be referred to as a "PBCH TTI," and the PBCH TTI may be 40 ms. That is, the MIB may be changed for each PBCH TTI.

[0083] The MIB may be configured with 40 bits. Of the 40 bits constituting the MIB, 3 bits may be used to indicate a system band, 3 bits may be used to indicate PHICH (physical hybrid ARQ (automatic repeat request) indicator channel) related information, 8 bits may be used to indicate SFN, 10 bits may be set as reserved bits, and 16 bits may be used for CRC (cyclic redundancy check).

[0084] The SFN that separates radio frames may consist of a total of 10 bits (B9 to B0), of which the 8 most significant bits (MSBs) (B9 to B2) may be indicated by the PBCH (i.e., the MIB). The 8 most significant bits (B9 to B2) of the SFN indicated by the PBCH (i.e., the MIB) may be the same for four consecutive radio frames (i.e., the PBCH TTIs). The 2 least significant bits (LSBs) (B1 to B0) of the SFN may change for four consecutive radio frames (i.e., the PBCH TTIs) and may not be explicitly indicated by the PBCH (i.e., the MIB). The 2 least significant bits (LSBs) (B1 to B0) of the SFN may be implicitly indicated by the scrambling sequence for the PBCH (hereinafter referred to as the "PBCH scrambling sequence").

[0085] A gold sequence generated by initializing with a cell ID may be used as the PBCH scrambling sequence, and the PBCH scrambling sequence may be initialized every four consecutive radio frames (i.e., PBCH TTI) by mod(SFN, 4). PBCHs transmitted in radio frames corresponding to SFNs whose two least significant bits (B1-B0) are set to '00' may be scrambled by the gold sequence generated by initializing with a cell ID. Thereafter, the gold sequence generated by mod(SFN, 4) may be used to scramble PBCHs transmitted in radio frames whose two least significant bits (B1-B0) of SFN are '01', '10', and '11'.

[0086] Therefore, a terminal that acquires a cell ID during the initial cell search process can implicitly find the value (e.g., "00," "01," "10," or "11") of the SFN's two least significant bits (B1-B0) through the PBCH scrambling sequence during the PBCH (i.e., MIB) decoding process. The terminal can identify the SFN (i.e., all bits (B9-B0) of the SFN) using the two least significant bits (B1-B0) of the SFN identified based on the PBCH scrambling sequence and the eight most significant bits (B9-B2) of the SFN indicated by the PBCH (i.e., MIB).

[0087]

[0088] Evolved mobile communications networks beyond LTE must not only maintain high transmission speeds, which was previously the primary focus, but also meet technical requirements to support a wider variety of service scenarios. The ITU-R recently defined the key performance indicators (KPIs) and requirements for IMT-2020, the official name for 5G mobile communications, which can be summarized as high transmission speeds (eMBB, enhanced Mobile Broadband), low transmission latency (URLLC, Ultra Reliable Low Latency Communication), and massive machine-type communication (mMTC, massive terminal connectivity). According to the ITU-R's estimated timetable, it aims to allocate frequencies for IMT-2020 in 2019 and complete international standard approval by 2020.

[0089] 3GPP is developing 5G standards based on new radio access technology (RAT) that meets the requirements of IMT-2020. According to the 3GPP definition, new radio access technology is a radio access technology that does not have backward compatibility with existing 3GPP radio access technology, and new wireless communication systems after LTE that adopt such radio access technology are referred to as New Radio (NR) in this specification.

[0090] One of the features that distinguishes NR from the existing 3GPP systems, CDMA and LTE, is that it utilizes a wide range of frequency bands to increase transmission capacity. In relation to this, the ITU-sponsored WRC-15 decided to consider the 24.25 to 86 GHz band as a candidate frequency band for IMT-2020 as an agenda item for the next WRC-19. 3GPP is considering the sub-1 GHz to 100 GHz band as NR candidate bands.

[0091] Waveform technologies being discussed for NR include orthogonal frequency division multiplexing (OFDM), filtered OFDM, generalized frequency division multiplexing (GFDM), filter bank multi-carrier (FBMC), and universal filtered multi-carrier (UFMC). While each has its own advantages and disadvantages, cyclic prefix (CP)-based OFDM and single carrier-frequency division multiple access (SC-FDMA) remain effective methods for 5G systems due to their relatively low implementation complexity at the transmitter and receiver ends and their multiple-input multiple-output (MIMO) scalability. However, to flexibly support various 5G usage scenarios, it may be possible to simultaneously accommodate different waveform parameters on a single carrier without a guard band. Filtered OFDM and GFDM, which have a frequency spectrum with low out-of-band emissions (OOB), may be suitable for this purpose.

[0092] For convenience of explanation, the present invention assumes that CP-based OFDM is used as a waveform technology for wireless access. However, this is merely for convenience of explanation, and various embodiments of the present invention are not limited to a specific waveform technology. In general, the category of CP-based OFDM technology also includes Filtered OFDM and Spread Spectrum OFDM (e.g., DFT-spread OFDM).

[0093]

[0094] The subcarrier spacing of a communication system (e.g., an OFDM-based communication system) may be determined based on factors such as carrier frequency offset (CFO). CFO may be caused by factors such as the Doppler effect and phase drift, and may increase in proportion to the operating frequency. Therefore, to prevent degradation of communication system performance due to CFO, the subcarrier spacing may increase in proportion to the operating frequency. However, as the subcarrier spacing increases, CP overhead may increase. Therefore, the subcarrier spacing may be set based on channel characteristics according to the frequency band, radio frequency (RF) characteristics, etc.

[0095] Various numerologies are considered in the NR system. For example, the subcarrier spacing of a communication system can be set to 15 kHz, 30 kHz, 60 kHz, or 120 kHz. The subcarrier spacing of an LTE system can be 15 kHz, and the subcarrier spacing of an NR system can be 1, 2, 4, or 8 times the existing subcarrier spacing of 15 kHz. If the subcarrier spacing increases in increments of an exponential multiple of 2 of the existing subcarrier spacing, the frame structure can be easily designed.

[0096] A communication system can support a wide frequency band (e.g., hundreds of MHz to tens of GHz). Because the diffraction and reflection characteristics of radio waves are poor in high frequency bands, propagation loss (e.g., path loss, reflection loss, etc.) in high frequency bands may be greater than propagation loss in low frequency bands. Therefore, the cell coverage of a communication system supporting a high frequency band may be smaller than that of a communication system supporting a low frequency band. To address this issue, a beamforming scheme based on multiple antenna elements may be used to increase cell coverage in communication systems supporting high frequency bands.

[0097] Beamforming methods can include digital beamforming, analog beamforming, hybrid beamforming, etc. In a communication system using digital beamforming, beamforming gain can be obtained using multiple RF paths based on a digital precoder or codebook. In a communication system using analog beamforming, beamforming gain can be obtained through analog RF devices (e.g., phase shifters, power amplifiers (PAs), variable gain amplifiers (VGAs), etc.) and antenna arrays.

[0098] Digital beamforming requires a high-performance digital-to-analog converter (DAC) or analog-to-digital converter (ADC) and a transceiver unit corresponding to the number of antenna elements, which can increase the complexity of antenna implementation in order to increase beamforming gain. In a communication system using analog beamforming, multiple antenna elements are connected to a single transceiver unit via a phase shifter, so increasing the beamforming gain does not significantly increase the complexity of antenna implementation. However, the beamforming performance of a communication system using analog beamforming may be lower than that of a communication system using digital beamforming. Furthermore, in a communication system using analog beamforming, the phase shifter is adjusted in the time domain, which can result in inefficient use of frequency resources. Therefore, a hybrid beamforming method, which combines digital and analog methods, may be used.

[0099] When cell coverage is increased by using beamforming, not only the control channels and data channels of each terminal but also common control channels and common signals (e.g., reference signals, synchronization signals) for all terminals belonging to the cell coverage can be transmitted based on the beamforming scheme. When transmitting common control channels and signals to all terminals while increasing cell coverage by applying beamforming, it is difficult to transmit common control channels and signals to the entire cell coverage in a single transmission, and the common control channels and signals must be transmitted through multiple beams over a certain period of time. This transmission over several hours while changing multiple beams is called beam sweeping. When transmitting common control channels and signals using beamforming, such a beam sweeping operation is necessary.

[0100]

[0101] A terminal connecting to the system can acquire downlink frequency / time synchronization and cell ID information using a synchronization signal, and then acquire uplink synchronization through a random access procedure to form a radio link. In an NR system, the synchronization block / physical broadcast channel (SS / PBCH) block can also be transmitted using a beam sweeping method. The SS / PBCH block can be composed of PSS, SSS, PBCH, etc., and within the SS / PBCH block, the PSS, SSS, and PBCH can be composed using a time division multiplexing (TDM) method. The SS / PBCH block can also be referred to as an "SS block (SSB)." One SS / PBCH block can be transmitted using N consecutive OFDM symbols, where N can be an integer greater than or equal to 4. The base station can periodically transmit the SS / PBCH block, and the terminal can acquire frequency / time synchronization, cell ID, system information, etc. based on the SS / PBCH block received from the base station. The SS / PBCH block can be transmitted as follows:

[0102] FIG. 5 is a conceptual diagram illustrating a first embodiment of a method for transmitting SS / PBCH blocks in a communication system.

[0103] Referring to FIG. 5, one or more SS / PBCH blocks within an SS / PBCH block burst set may be transmitted using a beam sweeping scheme. Up to L SS / PBCH blocks may be transmitted within one SS / PBCH block burst set. L may be an integer greater than or equal to 2 and may be defined in the 3GPP standard. L may vary depending on the system frequency domain. Within an SS / PBCH block burst set, SS / PBCH blocks may be positioned contiguously or dispersedly. Contiguous SS / PBCH blocks may be referred to as an "SS / PBCH block burst." The SS / PBCH block burst set may be repeated periodically, and the system information (e.g., MIB) transmitted over the PBCH of the SS / PBCH blocks within the SS / PBCH block burst set may be identical. The SS / PBCH block index, SS / PBCH block burst index, OFDM symbol index, slot index, etc. may be indicated explicitly or implicitly by the PBCH.

[0104] FIG. 6 is a conceptual diagram illustrating a first embodiment of an SS / PBCH block in a communication system.

[0105] Referring to FIG. 6, the arrangement order within an SS / PBCH block may be "PSS → PBCH → SSS → PBCH." Within an SS / PBCH block, the PSS, SSS, and PBCH may be configured in a TDM manner. In a symbol where the SSS is located, the PBCH may be arranged in a frequency resource higher than the SSS and a frequency resource lower than the SSS. When the maximum number of SS / PBCH blocks is 8 in a frequency band below 6 GHz, the index of the SS / PBCH block may be determined based on a demodulation reference signal (DMRS) (hereinafter referred to as "PBCH DMRS") used for PBCH demodulation. When the maximum number of SS / PBCH blocks is 64 in a frequency band above 6 GHz, the 3 least significant bits of the 6 bits indicating the index of the SS / PBCH block may be determined based on the PBCH DMRS, and the remaining 3 most significant bits may be determined based on the PBCH payload.

[0106] The maximum system bandwidth that can be supported in an NR system may be 400 MHz. The size of the maximum bandwidth that can be supported by a terminal may vary depending on the terminal's capability. Therefore, a terminal can perform an initial access procedure (e.g., an initial connection procedure) using a portion of the system bandwidth of an NR system that supports wideband. To support access procedures for terminals that support various sizes of bandwidth, SS / PBCH blocks can be multiplexed on the frequency axis within the system bandwidth of an NR system that supports wideband. In this case, the SS / PBCH blocks can be transmitted as follows:

[0107] FIG. 7 is a conceptual diagram illustrating a second embodiment of a method for transmitting SS / PBCH blocks in a communication system.

[0108] Referring to FIG. 7, a wideband component carrier (CC) can include multiple bandwidth parts (BWPs). For example, a wideband CC can include four BWPs. A base station can transmit SS / PBCH blocks through each of BWPs #0 to #3 belonging to the wideband CC. A terminal can receive SS / PBCH blocks through one or more BWPs among BWPs #0 to #3 and perform initial access procedures using the received SS / PBCH blocks.

[0109] After detecting the SS / PBCH block, the UE can acquire system information (e.g., remaining minimum system information (RMSI)) and perform a cell access procedure based on the system information. The RMSI may be transmitted through a PDSCH scheduled by a PDCCH. Configuration information of a control resource set (CORESET) on which a PDCCH, including scheduling information for a PDSCH on which the RMSI is transmitted, may be transmitted through a PBCH within an SS / PBCH block. Multiple SS / PBCH blocks may be transmitted across the entire system bandwidth, and one or more of the multiple SS / PBCH blocks may be SS / PBCH blocks associated with the RMSI. The remaining SS / PBCH blocks may not be associated with the RMSI. The SS / PBCH block associated with the RMSI may be defined as a "cell-defining SS / PBCH block." The UE can perform a cell search procedure and an initial access procedure using the cell-defining SS / PBCH block. SS / PBCH blocks not associated with the RMSI may be used for synchronization and / or measurement procedures in a corresponding BWP. The BWP in which an SS / PBCH block is transmitted may be limited to one or more BWPs within a wide bandwidth.

[0110] The RMSI can be obtained by performing the following steps: acquire CORESET configuration information from the SS / PBCH block (e.g., PBCH) → detect PDCCH based on CORESET configuration information → acquire PDSCH scheduling information from PDCCH → receive RMSI through PDSCH. The PDCCH transmission resource can be configured according to the CORESET configuration information. The RMSI CORESET mapping pattern can be defined as follows: RMSI CORESET can be a CORESET used for transmitting and receiving RMSI.

[0111] FIG. 8 is a conceptual diagram for explaining the time domain transmission position of SSBs according to the subcarrier spacing and L.

[0112] The time domain position where SSB is transmitted can be defined differently depending on the subcarrier spacing and the L value. In symbols within a slot where no SSB is transmitted, short UL transmission such as UCI (Uplink control information) can be performed. In SSB transmission with a large subcarrier spacing (e.g., 120 kHz or 240 kHz SCS), a gap can be set in the middle of consecutive slots containing SSB so that long UL transmission such as URLLC traffic can be performed at least every 1 ms.

[0113] As shown in the example of Figure 8, a gap for UL transmission can be set after 8 slots including SSBs with 120 kHz subcarrier spacing, and a gap for UL transmission can be set after 16 slots including SSBs with 240 kHz subcarrier spacing.

[0114] As mentioned above, transmission locations are defined so that up to L SSBs can be transmitted within an SSB burst set, with the value of L varying depending on the frequency domain. For example, in FR1, up to four SSBs can be transmitted between 0 and 3 GHz, and up to eight SSBs above that frequency. In FR2, up to 64 SSBs can be transmitted. Depending on the environment, the system can transmit actual SSBs at all L locations, or only a portion of the L locations can be used for actual SSB transmission. When a terminal receiving data receives data at a location where SSBs can be transmitted, it determines whether to perform rate matching for the received data depending on whether actual SSB transmissions are occurring at that location. Information about the location where the SSBs are actually transmitted can be transmitted to the terminal via RMSI and / or UE-specific RRC signaling. When transmitted via RMSI, if L=4 or 8, the positions where actual SSBs are transmitted through bitmap information are represented by '1' and positions where no SSBs are transmitted are represented by '0'. If L=64, 64 pieces of position information are transmitted in a 16-bit compressed form. More specifically, L=64 SSBs are divided into 8 groups of 8, and the 8 SSBs within a group are represented by an 8-bit bitmap, and each of the 8 groups is represented by an 8-bit bitmap, with each bitmap consisting of 16 bits. Therefore, all groups have the same SSB transmission pattern within the group.

[0115] FIG. 9 is a conceptual diagram illustrating an example of notifying the actual transmission position of an SSB through RMSI in the FR2 band.

[0116] The parameter ssb-PositionsInBurst, which indicates the transmission position, consists of two parameters, inOneGroup and groupPresence, each of which consists of 8 bits. Of these, inOneGroup indicates the presence or absence of transmission for each SSB within the group using an 8-bit bitmap, and groupPresence indicates the presence or absence of transmission for each group. In this case, all groups signaled as being transmitted via groupPresence (indicated as "1" in the 8-bit bitmap) have the same SSB transmission position pattern signaled by inOneGroup. Signaling in this manner reduces signaling overhead by signaling the transmission position using 16 bits for 64 possible SSB transmission positions, but the signaled transmission position may differ from the actual transmission position. For example, in Figure 9, even if the patterns for the first and third groups are actually operated separately, this cannot be signaled. Therefore, to solve this problem, the actual transmission position of the SSB is additionally signaled in a 64-bit bitmap through UE-specific RRC signaling. When this information is transmitted through UE-specific RRC signaling, everything is transmitted in the full bitmap regardless of the L value.

[0117] As described above, RMSI reception is performed through a series of processes, including detecting the PDCCH through the CORESET configuration information transmitted through the PBCH, acquiring RMSI scheduling information through the PDCCH, and then receiving the PDSCH accordingly. At this time, a control channel resource region in which the PDCCH can be transmitted is set through the RMSI CORESET configuration information, which can be broadly divided into three patterns as follows:

[0118] FIG. 10a is a conceptual diagram illustrating RMSI CORESET mapping pattern #1 in a communication system, FIG. 10b is a conceptual diagram illustrating RMSI CORESET mapping pattern #2 in a communication system, and FIG. 10c is a conceptual diagram illustrating RMSI CORESET mapping pattern #3 in a communication system.

[0119] 10a to 10c, one of RMSI CORESET mapping patterns #1-3 may be used, and detailed configuration may be completed according to one RMSI CORESET mapping pattern. In RMSI CORESET mapping pattern #1, the SS / PBCH block, CORESET (e.g., RMSI CORESET), and PDSCH (e.g., RMSI PDSCH) may be configured in a TDM manner. RMSI PDSCH may refer to a PDSCH through which RMSI is transmitted. In RMSI CORESET mapping pattern #2, the CORESET (e.g., RMSI CORESET) and PDSCH (e.g., RMSI PDSCH) may be configured in a TDM manner, and the PDSCH (e.g., RMSI PDSCH) may be configured with the SS / PBCH block in a frequency division multiplexing (FDM) manner. In RMSI CORESET mapping pattern #3, the CORESET (e.g., RMSI CORESET) and PDSCH (e.g., RMSI PDSCH) may be configured in a TDM manner, and the CORESET (e.g., RMSI CORESET) and PDSCH (e.g., RMSI PDSCH) may be configured with the SS / PBCH block in an FDM manner.

[0120] In frequency bands below 6 GHz, only RMSI CORESET mapping pattern #1 can be used. In frequency bands above 6 GHz, RMSI CORESET mapping patterns #1, #2, and #3 can all be used. The numerology of the SS / PBCH block can be different from the numerology of "RMSI CORESET and RMSI PDSCH." Here, the numerology can be the subcarrier spacing. In RMSI CORESET mapping pattern #1, all numerology combinations can be used. In RMSI CORESET mapping pattern #2, the combination of "SS / PBCH block, RMSI CORESET / PDSCH = 120 kHz, 60 kHz or 240 kHz, 120 kHz" can be used. In RMSI CORESET mapping pattern #3, the combination of "SS / PBCH block, RMSI CORESET / PDSCH = 120 kHz, 120 kHz" can be used.

[0121] One of RMSI CORESET mapping patterns #1-3 can be selected by combining the numerology of the SS / PBCH block and the numerology of the RMSI CORESET / PDSCH. RMSI CORESET configuration information can include Table A and Table B. Table A can indicate the number of RBs (resource blocks) of the RMSI CORESET, the number of symbols of the RMSI CORESET, and the offset between the RBs (e.g., start RB or end RB) of the SS / PBCH block and the RBs (e.g., start RB or end RB) of the RMSI CORESET. Table B can indicate the number of search space sets per slot, the offset of the RMSI CORESET, and the OFDM symbol index for each RMSI CORESET mapping pattern. Table B can indicate information for configuring the RMSI PDCCH monitoring occasion. Table A and Table B can each consist of multiple tables. For example, Table A may include Tables 13-1 to 13-8 specified in TS 38.213, and Table B may include Tables 13-9 to 13-13 specified in TS 38.213. The size of each of Table A and Table B may be 4 bits.

[0122] JPEG2026504903000002.jpg30163

[0123]

number

[0124]

[0125] JPEG2026504903000004.jpg155163

[0126] 11a to 11c are diagrams illustrating various examples of setting Type0 CSS slots corresponding to SSB indices.

[0127] JPEG2026504903000005.jpg39161

[0128] JPEG2026504903000006.jpg21161

[0129] JPEG2026504903000007.jpg22161

[0130]

[0131] In an NR system, the PDSCH may be mapped to the time domain using PDSCH mapping type A or B. PDSCH mapping types A and B may be defined as shown in Table 1 below.

[0132] [Table 1]

[0133]

[0134] Type A (i.e., PDSCH mapping type A) can be slot-based transmission. When Type A is used, the position of the starting symbol of the PDSCH can be set to one of {0, 1, 2, 3}. When Type A and a normal CP are used, the number of symbols constituting the PDSCH (e.g., the PDSCH duration) can be set to one of 3 to 14 within a symbol boundary. Type B (i.e., PDSCH mapping type B) can be non-slot-based transmission. When Type B is used, the position of the starting symbol of the PDSCH can be set to one of 0 to 12. When Type B and a normal CP are used, the number of symbols constituting the PDSCH (e.g., the PDSCH duration) can be set to one of {2, 4, 7} within a symbol boundary. A DMRS (hereinafter referred to as "PDSCH DMRS") for demodulating a PDSCH (e.g., data) may be determined based on an ID indicating a PDSCH mapping type (e.g., Type A or Type B) and length. The ID may be defined differently depending on the PDSCH mapping type.

[0135]

[0136] With NR Phase 1 standardization completed in Rel-15 and Phase 2 standardization beginning in Rel-16, new features for the NR system are being discussed. One of the most prominent is NR-U (Unlicensed). NR-U is a technology that supports operation in unlicensed spectrum used for applications such as Wi-Fi to improve the utilization of limited frequency resources and increase network capacity. Standardization began in Rel-13 as LTE-LAA (Licensed-Assisted Access) technology and continued to evolve through Rel-14 LTE-eLAA (Enhanced LAA) and Rel-15 LTE-feLAA (Further Enhanced LAA). Following the SI for NR-U, standardization work is also underway through WI in Rel-16.

[0137] In an NR-U system, a terminal can determine whether or not a base station transmits a signal based on a discovery reference signal (DRS) received from the base station, just like in a general NR system. In an NR-U system in stand-alone (SA) mode, a terminal can acquire synchronization and / or system information based on the DRS. In an NR-U system, the DRS can be transmitted in accordance with unlicensed band regulations (e.g., transmission band, transmission power, transmission time, etc.). For example, in accordance with the occupied channel bandwidth (OCB) regulations, a signal can be configured and / or transmitted to occupy 80% of the entire channel bandwidth (e.g., 20 MHz).

[0138] In an NR-U system, a communication node (e.g., a base station or a terminal) can perform Listen Before Talk (LBT) before transmitting a signal and / or channel to coexist with other systems. The signal can be a synchronization signal, a reference signal (e.g., DRS, DMRS, channel state information (CSI)-RS, phase tracking (PT)-RS, sounding reference signal (SRS)), etc. The channel can be a downlink channel, an uplink channel, a sidelink channel, etc. In the embodiments, a signal can refer to a "signal," a "channel," or a "signal and channel." LBT can be an operation to check whether a signal is being transmitted by another communication node. If the LBT determines that there is no transmission signal (e.g., if the LBT is successful), the communication node can transmit a signal in an unlicensed spectrum. If the LBT determines that there is a transmission signal (e.g., if the LBT is unsuccessful), the communication node may not be able to transmit a signal in an unlicensed spectrum. A communication node can perform LBT according to various categories before transmitting a signal. The LBT category can vary depending on the type of transmission signal.

[0139]

[0140] Meanwhile, NR V2X (vehicular to everything) communication technology is being discussed at the NR standardization conference. NR V2X communication technology is based on D2D (device to device) communication technology and can support communication between vehicles, between vehicles and infrastructure, and between vehicles and pedestrians. Technologies to reduce power consumption and improve reliability for NR V2X communication are being discussed.

[0141] NR V2X communication (e.g., sidelink communication) can be performed using three transmission methods (e.g., unicast, broadcast, and groupcast). When the unicast method is used, a PC5-RRC connection can be established between a first terminal (e.g., a transmitting terminal transmitting data) and a second terminal (e.g., a receiving terminal receiving data). The PC5-RRC connection can refer to a logical connection between a source ID of the first terminal and a destination ID of the second terminal. The first terminal can transmit data (e.g., sidelink data) to the second terminal. When the broadcast method is used, the first terminal can transmit data to all terminals. When the groupcast method is used, the first terminal can transmit data to a group (e.g., a groupcast group) consisting of multiple terminals. In SL communication (e.g., SL-U communication), the transmitting terminal can refer to a terminal transmitting data, and the receiving terminal can refer to a terminal receiving data.

[0142] When a unicast scheme is used, the second terminal may transmit feedback information (e.g., an acknowledgement (ACK) or a negative ACK (NACK)) for data received from the first terminal to the first terminal. In the following embodiments, the feedback information may be referred to as a "HARQ-ACK," a "feedback signal," a "physical sidelink feedback channel (PSFCH) signal," or the like. If an ACK is received from the second terminal, the first terminal may determine that the data has been successfully received by the second terminal. If a NACK is received from the second terminal, the first terminal may determine that the second terminal has failed to receive the data. In this case, the first terminal may transmit additional information to the second terminal based on a hybrid automatic repeat request (HARQ) scheme. Alternatively, the first terminal may retransmit the same data to the second terminal, thereby improving the probability of data reception by the second terminal.

[0143] When the broadcast method is used, the transmission procedure of feedback information for data may not be performed. For example, system information may be transmitted in a broadcast manner, and the terminal may not transmit feedback information for the system information to the base station. Therefore, the base station may not know whether the terminal has successfully received the system information. To solve this problem, the base station may periodically broadcast system information.

[0144] When a groupcast method is used, a feedback information transmission procedure for data may not be performed. For example, necessary information may be periodically transmitted in a groupcast manner without a feedback information transmission procedure. However, if the target and / or number of terminals participating in groupcast-based communication are limited and the data transmitted in the groupcast manner must be received within a predetermined time (e.g., delay-sensitive data), a feedback information transmission procedure may be required even in groupcast sidelink communication. Groupcast sidelink communication may refer to sidelink communication performed in a groupcast manner. When a feedback information transmission procedure is performed in groupcast sidelink communication, data can be transmitted and received efficiently and stably.

[0145] Two HARQ-ACK feedback methods (e.g., feedback information transmission procedures) may be supported in groupcast sidelink communication. When there are many receiving terminals in a sidelink group and service scenario 1 is supported, some receiving terminals within a specific range in the sidelink group may transmit a NACK over the PSFCH if data reception fails. This method may be "groupcast HARQ-ACK feedback option 1." In service scenario 1, some receiving terminals within a specific range may be allowed to receive in a best-effort manner instead of all receiving terminals in the sidelink group. Service scenario 1 may be an extended sensor scenario in which some receiving terminals within a specific range need to receive the same sensor information from the transmitting terminal. In this embodiment, a transmitting terminal may refer to a terminal transmitting data, and a receiving terminal may refer to a terminal receiving data.

[0146] When the number of receiving terminals in a sidelink group is limited and service scenario 2 is supported, all receiving terminals in the sidelink group can individually report HARQ-ACK for data through a separate PSFCH. This method may be referred to as "groupcast HARQ-ACK feedback option 2." Since PSFCH resources are sufficient in service scenario 2, the transmitting terminal can monitor HARQ-ACK feedback for all receiving terminals in the sidelink group, and data reception can be guaranteed for all receiving terminals in the sidelink group.

[0147] Like broadcast sidelink communication, data can be transmitted and received in unicast and groupcast sidelink communication without the HARQ-ACK feedback procedure. In this case, the transmitting terminal can retransmit data a predetermined number of times to increase the probability of data reception.

[0148] In all transmission methods (e.g., unicast transmission, groupcast transmission, broadcast transmission), whether or not to apply the HARQ-ACK feedback procedure can be configured by the UE(s) permanently or semi-permanently through signaling (e.g., system information signaling, PC5-RRC signaling, UE-specific RRC signaling, control information signaling). In sidelink communication, HARQ-ACK feedback information can be transmitted on the PSFCH. If PSSCH reception is successful, the receiving UE can transmit an ACK for the PSSCH (e.g., data) on the PSFCH. If PSSCH reception is unsuccessful, the receiving UE can transmit a NACK for the PSSCH (e.g., data) on the PSFCH. The PSFCH can be a channel for reporting ACK / NACK information (e.g., HARQ-ACK feedback) to the transmitting UE. A resource region (e.g., a PSFCH resource region) for PSFCH transmission (e.g., HARQ-ACK feedback transmission) can be pre-configured within a specific resource pool. The PSFCH (e.g., PSFCH resource, PSFH resource region) may be configured periodically. The PSFCH period for the PSFCH resource may be k slots (e.g., logical sidelink (SL) slots). k may be a natural number. For example, k may be 1, 2, or 4.

[0149] FIG. 12 is a conceptual diagram illustrating a first embodiment of slot configuration in which a PSFCH is configured.

[0150] 12, within a slot (e.g., an SL slot), a PSFCH (e.g., HARQ-ACK feedback) may be repeatedly transmitted using two symbols (e.g., two OFDM symbols). The first symbol of the two symbols in which the PSFCH is transmitted may be used for automatic gain control (AGC) to adjust the correct PSFCH reception power level.

[0151] The PSFCH may be transmitted within a frequency resource region preset by system information. In this case, the frequency resource region for PSFCH transmission may be indicated (e.g., signaled) in the form of a bitmap within a resource pool. The receiving terminal may implicitly select the location of the frequency resource region for PSFCH transmission based on the slot and subchannel index in which the PSFCH is received. The receiving terminal may determine the number of PSFCH resources that can be multiplexed within the frequency resource region based on the resource block (RB) and the cyclic shift of the PSFCH sequence. The receiving terminal may implicitly select a PSFCH index for the PSFCH resource(s) based on a source ID and a member ID. The source ID may be a physical layer source ID. The source ID may be the ID of the transmitting terminal that transmitted the PSSCH.

[0152] The member ID may be used in groupcast HARQ-ACK feedback option 2. When groupcast HARQ-ACK feedback option 2 is applied, all receiving terminals in the group may individually transmit HARQ-ACK feedback for SL data through a separate PSFCH (e.g., PSFCH resource). Different from the above embodiment, the member ID may be set to 0.

[0153] FIG. 13 is a conceptual diagram illustrating a first embodiment of a PSFCH for ACK / NACK transmission.

[0154] Referring to FIG. 13, the transmission time of the PSFCH may be the first slot (e.g., PSFCH slot) in which PSFCH transmission is possible after a preset time (e.g., sl-MinTimeGapPSFCH) from the reception time of the PSSCH. The PSFCH slot may be a slot in which PSFCH transmission is possible and / or a slot in which PSFCH is configured. The sl-MinTimeGapPSFCH may be configured taking into consideration "the time for processing the PSSCH after receiving the PSSCH" and "the time for preparing an ACK / NACK (e.g., HARQ-ACK feedback) depending on whether the PSSCH is successfully received." The sl-MinTimeGapPSFCH may be configured as two or three slots. A terminal (e.g., a receiving terminal) may transmit the PSFCH in slot #n+12, which is a slot in which PSFCH transmission is possible after the sl-MinTimeGapPSFCH (e.g., three slots) from the reception time of the PSSCH. n may be an integer greater than or equal to 0. In the present disclosure, a reception time may refer to a reception start time and / or reception end time, a transmission time may refer to a transmission start time and / or transmission end time, and a time may refer to time and / or duration.

[0155]

[0156] The reliability of transmission at the receiving terminal can be improved by appropriately adjusting the power of the transmitting terminal according to the transmission environment. Interference to other terminals can be mitigated by appropriately adjusting the power of the transmitting terminal. Energy efficiency can be improved by reducing unnecessary transmission power. Power control methods can be classified into open-loop power control and closed-loop power control. In the open-loop power control method, the transmitting terminal can determine the transmission power taking into account the configured and measured environment, etc. In the closed-loop power control method, the transmitting terminal can determine the transmission power based on the transmit power control (TPC) command received from the receiving terminal.

[0157] It can be difficult for a receiving terminal to predict the strength of a received signal due to various factors, including multipath fading channels and interference. Therefore, the receiving terminal can adjust the received power level (e.g., received power range) by performing automatic gain control (AGC) to prevent quantization errors in the received signal and maintain appropriate received power. In a communication system, a terminal can perform AGC using a reference signal received from a base station. However, in sidelink communication (e.g., V2X communication), the reference signal may not be transmitted from the base station. In other words, communication between terminals can be performed without a base station in sidelink communication. Therefore, performing AGC in sidelink communication can be difficult. In sidelink communication, a transmitting terminal can transmit a signal (e.g., a reference signal) to a receiving terminal before transmitting data. The receiving terminal can then adjust the received power range (e.g., received power level) by performing AGC based on the signal received from the transmitting terminal. The transmitting terminal can then transmit sidelink data to the receiving terminal. The signal used for AGC may be a duplicated signal of a subsequently transmitted signal or a signal previously set between terminals.

[0158] The time interval required for AGC operation may be 15 μs. When the subcarrier spacing is 15 kHz in an NR system, the time interval (e.g., length) of one symbol (e.g., OFDM symbol) may be 66.7 μs. When the subcarrier spacing is 30 kHz in an NR system, the time interval (e.g., OFDM symbol) may be 33.3 μs. In the following examples, a symbol may refer to an OFDM symbol. In other words, the time interval of one symbol may be more than twice the time interval required for AGC operation.

[0159] For sidelink communication, transmission of a data channel for data transmission and a control channel including scheduling information for data resource allocation may be required. In sidelink communication, the data channel may be a Physical Sidelink Shared Channel (PSSCH), and the control channel may be a Physical Sidelink Control Channel (PSCCH). The data channel and the control channel may be multiplexed in a resource domain (e.g., a time and frequency resource domain).

[0160] FIG. 14 is a conceptual diagram illustrating an embodiment of a method for multiplexing a control channel and a data channel in sidelink communication.

[0161] Referring to FIG. 14, sidelink communication can support Option 1A, Option 1B, Option 2, and Option 3. If Option 1A and / or Option 1B are supported, the control channel and the data channel can be multiplexed in the time domain. If Option 2 is supported, the control channel and the data channel can be multiplexed in the frequency domain. If Option 3 is supported, the control channel and the data channel can be multiplexed in both the time and frequency domains. Sidelink communication can basically support Option 3.

[0162] The basic unit of resource configuration in sidelink communication (e.g., NR-V2X sidelink communication) may be a subchannel. A subchannel may be defined as a time and frequency resource. For example, a subchannel may consist of multiple symbols (e.g., OFDM symbols) in the time domain and multiple resource blocks (RBs) in the frequency domain. A subchannel may be referred to as an RB set. Within a subchannel, a data channel and a control channel may be multiplexed based on Option 3.

[0163] In sidelink communication (e.g., NR-V2X sidelink communication), transmission resources may be allocated based on Mode 1 or Mode 2. When Mode 1 is used, the base station may allocate sidelink resources for data transmission within a resource pool to a transmitting terminal, and the transmitting terminal may transmit data to a receiving terminal using the sidelink resources allocated by the base station. Here, the transmitting terminal may be a terminal that transmits data in sidelink communication, and the receiving terminal may be a terminal that receives data in sidelink communication.

[0164] When Mode 2 is used, the transmitting terminal can autonomously select sidelink resources to use for data transmission by performing a resource sensing operation (e.g., a resource sensing procedure) and / or a resource selection operation (e.g., a resource selection procedure) within a resource pool. The base station can configure a resource pool for Mode 1 and a resource pool for Mode 2 to the terminal(s). The resource pool for Mode 1 can be defined independently of the resource pool for Mode 2, or a common resource pool can be configured for Mode 1 and Mode 2.

[0165] When Mode 1 is used, the base station can schedule resources to be used for sidelink data transmission to the transmitting terminal, and the transmitting terminal can transmit sidelink data to the receiving terminal using the resources scheduled by the base station. Therefore, resource collisions between terminals can be prevented. When Mode 2 is used, the transmitting terminal can select any resource by performing resource sensing and / or resource selection, and can transmit sidelink data using any selected resource. Since the above procedures are performed based on the individual resource sensing and / or resource selection operations of each transmitting terminal, collisions between selected resources may occur.

[0166] FIG. 15 is a conceptual diagram illustrating a first embodiment of the resource selection operation.

[0167] 15, a terminal (e.g., a transmitting terminal) may perform a resource sensing operation within a sensing window and may perform a resource selection operation on the sensed resource(s) (e.g., candidate resource(s)) within a selection window. If the resource selection operation is triggered at n, the terminal may select suitable resource(s) within the selection window (e.g., the interval from n+T1 to n+T2) based on the sensing result (e.g., the resource(s) sensed by the resource sensing operation) within the sensing window (e.g., the interval from n-T0 to n-Tproc,0).

[0168] The UE may eliminate candidate resource(s) within the selection window that do not satisfy the conditions based on the result of the resource sensing operation. In other words, the UE may determine the remaining candidate resources after eliminating unsuitable candidate resource(s) from the total candidate resources. If the ratio of the remaining candidate resources to the total resources within the selection window is less than a reference ratio, the UE may relax the conditions for excluding the candidate resource(s). For example, the UE may increase the reference signal received power (RSRP) threshold, which is a condition for excluding the candidate resource(s), by 3 dB. The UE may then perform the resource selection operation again. The reference ratio may be preset to one of 20%, 35%, or 50% according to priority. If the ratio of the remaining candidate resources is equal to or greater than the reference ratio, the UE may randomly select the final resource(s) to be used for SL transmission from the remaining candidate resources. The UE may perform SL transmission using the final resource(s).

[0169] FIG. 16 is a conceptual diagram illustrating a first embodiment of a resource re-selection operation.

[0170] Referring to FIG. 16, after the resource selection operation, the UE may perform a resource reselection operation taking into consideration aperiodic data transmission, etc. After performing the operation shown in FIG. 13, the UE may perform a resource reselection operation by additionally considering the sensing result before the actual SL transmission (m-T3). The resource reselection operation may be performed within a reselection window. The UE may additionally determine the suitability of the resource(s) reserved in m. If the resource(s) reserved in m are determined to be suitable, the UE may perform SL transmission using the reserved resource(s). If the resource(s) reserved in m are determined to be unsuitable, the UE may reselect the resource(s) for SL transmission and perform SL transmission using the reselected resource(s).

[0171] If an independent SL carrier is not configured for SL communication, some UL resources among UL resources may be configured as SL resources through the SL resource pool configuration procedure. A bitmap may be repeatedly applied to the remaining slots within a specific period, excluding slots in which at least X UL symbols are not configured and slots in which S(sidelink)-SSB is transmitted. X may be a natural number. The bitmap may indicate the slots to be used as SL resources. For example, slots corresponding to bits set to 1 in the bitmap may be used as SL resources.

[0172] This can be assumed to be the case when 15 kHz SCS (subcarrier spacing) is applied and X or more UL symbols are configured in all slots. If there are 10,240 available slots in a DFN (direct frame number), the S-SSB transmission period is 160 ms, and there are two slots used for S-SSB transmission in each S-SSB transmission period, the number of slots used for S-SSB transmission in the DFN can be 128. The bitmap for SL time resource configuration can include 10 bits. If the bitmap (e.g., a bitmap including 10 bits) is repeatedly applied to the remaining 10,112 slots, excluding the 128 slots used for S-SSB transmission, there may be two slots (e.g., reserved slots) to which the bitmap does not apply. It may be necessary to exclude two reserved slots. If the two reserved slots are excluded from the 10,112 slots, 10,110 slots remain. The bitmap (e.g., a bitmap including 10 bits) can be applied 1011 times to 10110 slots. If the bitmap is 1111000000 and slots corresponding to bits set to 1 are used as SL resources, 4044 slots can be configured as SL resources in the DFN. In other words, 4044 slots out of 10240 slots can be used for SL communication depending on the configuration of the SL resource pool.

[0173] A sidelink communication system supporting Rel-16 may be designed for terminals with no significant battery capacity constraints (e.g., terminals mounted on automobiles, V-UEs (vehicle UEs)). Therefore, power reduction issues may not be a major consideration in the resource sensing / selection operations of terminals. In a sidelink communication system supporting Rel-17, a power reduction method may be necessary for sidelink communication with terminals with battery capacity constraints (e.g., terminals carried by pedestrians, terminals mounted on bicycles, terminals mounted on motorcycles, P-UEs (pedestrian UEs)). In this disclosure, V-UE may refer to a terminal with no significant battery capacity constraints, P-UE may refer to a terminal with battery capacity constraints, and "resource sensing / selection operations" may include "resource sensing operations and / or resource selection operations." A resource sensing operation may refer to a partial sensing operation or a full sensing operation. A resource selection operation may refer to a random selection operation. Also, in this disclosure, "operations of the terminal" may be interpreted as "operations of the V-UE" and / or "operations of the P-UE."

[0174] In LTE V2X, partial sensing and / or random selection can be introduced to reduce power consumption. If partial sensing is supported, the UE can perform resource sensing for a portion of the sensing window instead of the entire window, and can select resources based on the results of the partial sensing. This can reduce the UE's power consumption.

[0175] In Rel-14 LTE V2X, only periodic data transmission and reception may be possible. In Rel-14 LTE V2X, a terminal may arbitrarily select candidate slots considering a preset minimum number in a resource selection interval (e.g., a selection window) and perform partial sensing operations considering a period of k × 100 ms. k may be signaled using a bitmap (e.g., a bitmap including 10 bits). k may be determined based on the position of the bitmap (e.g., the bits included in the bitmap). For example, the 10 bits included in the bitmap may correspond to 1 to 10 starting from the MSB, and the period may be determined based on the value corresponding to the bit set to 1. The value corresponding to the bit set to 1 may be k.

[0176] If the MSB in the bitmap is set to 1, k may be 1. In this case, the terminal can perform partial sensing operations considering a 100 ms (= 1 x 100 ms) period. If the bit next to the MSB in the bitmap is set to 1, k may be 2. In this case, the terminal can perform partial sensing operations considering a 200 ms (= 2 x 100 ms) period. If the LSB in the bitmap is set to 1, k may be 10. In this case, the terminal can perform partial sensing operations considering a 1000 ms (= 10 x 100 ms) period.

[0177] In Rel-14 LTE V2X, the period (e.g., the period of a partial sensing operation) may be configured as 20 ms or 50 ms. The 20 ms or 50 ms period may not be supported in the resource pool for P-UE. In the NR communication system, in addition to the {0, 100 ms, 200 ms, ..., 1000 ms} period, shorter periods may be supported. The shorter periods may be {1 ms, 2 ms, ..., 99 ms}. Up to 16 periods may be selected in the resource pool, and the selected period may be pre-configured in the UE. The UE may perform a resource sensing operation and / or a resource (re)selection operation using one or more of the configured periods. If a random selection operation is supported, the UE may randomly select resources without performing a resource sensing operation. Alternatively, the random selection operation may be performed together with the resource sensing operation. For example, the UE may determine resources by performing a resource sensing operation and select resource(s) by performing a random selection operation within the determined resources.

[0178] In LTE V2X supporting Rel-14, resource pools capable of performing partial sensing and / or random selection operations can be configured independently of resource pools capable of performing complete sensing operations. Resource pools capable of performing random selection operations, partial sensing operations, and random selection and partial sensing operations can be configured independently. In other words, random selection operations, partial sensing operations, or "random selection and partial sensing operations" can be configured in each resource pool. When both random selection operations and partial sensing operations are configured in a resource pool, the UE can select one of the random selection operations and partial sensing operations, select resources by performing the selected operation, and perform sidelink communication using the selected resources.

[0179] In LTE V2X supporting Rel-14, SL data may be transmitted periodically based on a broadcast scheme. In an NR communication system, SL data may be transmitted based on at least one of a broadcast scheme, a multicast scheme, a groupcast scheme, or a unicast scheme. In addition, in an NR communication system, SL data may be transmitted periodically or aperiodically. A transmitting terminal may transmit SL data to a receiving terminal, and the receiving terminal may transmit HARQ-ACK feedback (e.g., ACK or NACK) for the SL data to the transmitting terminal via a PSFCH. In this disclosure, a transmitting terminal may refer to a terminal that transmits SL data, and a receiving terminal may refer to a terminal that receives SL data.

[0180] A terminal with reduced capabilities (hereinafter referred to as a "RedCap terminal") can operate in a specific usage environment. The capabilities of a RedCap terminal may be lower than those of a normal new radio (NR) terminal, but higher than those of an LTE-MTC (machine type communication) terminal, a narrow band (NB)-IoT (Internet of Things) terminal, and a low power wide area (LPWA) terminal. For example, there may be terminals requiring high data rates and low latency (e.g., surveillance cameras) and / or terminals requiring low data rates, high latency, and high reliability (e.g., wearable devices). To support these terminals, the maximum carrier bandwidth may be reduced from 100 MHz to 20 MHz in FR1 and from 400 MHz to 100 MHz in FR2. The number of receive antennas in a RedCap terminal may be smaller than that of a normal NR terminal. If the carrier bandwidth and the number of receiving antennas are reduced, the receiving performance of the RedCap terminal may decrease, and the coverage of the RedCap terminal may decrease accordingly.

[0181] A communication system (e.g., an NR system) can operate in a frequency band higher than the 52.6 GHz frequency band. As the frequency band in which a communication system operates increases, frequency offset error and phase noise may increase. For robust operation in such an environment, the use of a large SCS may be necessary. In the FR2 band, 60 kHz SCS and / or 120 kHz SCS may be supported, and 480 kHz SCS and / or 960 kHz SCS may additionally be supported. Furthermore, a "physical layer signal and channel design" and "physical layer procedure" based on a new SCS may be required. In connection with the initial access procedure, 120 kHz SSB and / or 240 kHz SSB may be supported in the FR2 band, and 480 kHz SSB and / or 960 kHz SSB may additionally be supported. Here, 120 kHz SSB may refer to SSB transmitted over radio resources to which 120 kHz SCS is applied, and 240 kHz SSB may refer to SSB transmitted over radio resources to which 240 kHz SCS is applied. To support the new SCS, an "initial BWP configuration method" and "SSB burst aggregation pattern" may be necessary.

[0182]

[0183] Two-way communication (duplex) between communication nodes (e.g., a base station and a terminal) can be performed based on half-duplex or full-duplex. In half-duplex, a communication node can perform either a signal transmission operation or a signal reception operation at a given time. In other words, a communication node can perform transmission and reception operations only at different times. In full-duplex, a communication node can perform transmission and reception operations simultaneously or at different times. Full-duplex communication can be easily performed in a frequency division duplex (FDD) system (e.g., a system using FDD carriers, paired spectrum, etc.). Communication nodes can perform transmission and reception operations in separate frequency domains (e.g., uplink carrier and downlink carrier), respectively. Therefore, interference between signals in the separate frequency domains can be very small. On the other hand, even in TDD systems (e.g., systems using TDD carriers, unpaired spectrum, etc.), communication nodes can perform transmission and reception within a common frequency domain (e.g., a carrier commonly used for uplink and downlink transmission), and when transmission and reception are performed simultaneously, the transmission signal may interfere with the reception signal. Therefore, self-interference cancellation technology may be required to perform full-duplex communication in a TDD system. Full-duplex communication in a TDD system may be referred to as in-band full-duplex communication. On the other hand, half-duplex communication can be easily performed in both FDD and TDD systems because it does not have the aforementioned interference issues.

[0184] FIG. 17 is a conceptual diagram for explaining full-duplex communication in the same band.

[0185] Referring to FIG. 17, a base station 1701 can perform bidirectional communication with terminals 1702 and 1703 based on a full-duplex scheme. That is, the base station 1701 can perform both transmission and reception at the same time. Conversely, the terminals 1702 and 1703 can perform only one of transmission and reception at a time. For example, the base station 1701 can transmit a downlink signal to a first terminal 1702 at time t1 and simultaneously receive an uplink signal from a second terminal 1703 at time t1. The downlink signal and the uplink signal can be transmitted in the same band (e.g., within the same carrier). In this case, the downlink signal can act as self-interference in the base station's reception of the uplink signal. The base station can improve the reception performance of the uplink signal by removing or mitigating the self-interference before detecting the uplink signal from the received signal.

[0186] Furthermore, an uplink signal transmitted by the second terminal 1703 may interfere with the reception of a downlink signal by the first terminal 1702. Interference between an uplink signal and a downlink signal (e.g., an uplink signal and a downlink signal transmitted and received from different nodes (i.e., the first terminal and the second terminal)) may be referred to as cross-link interference. When the distance between the first terminal 1702 and the second terminal 1703 is short, or when the receiving beam direction of the first terminal 1702 is similar to the transmitting beam direction of the second terminal 1703, the strength of the cross-link interference that the uplink signal exerts on the downlink transmission may be large. Therefore, the reception performance of the downlink signal by the first terminal 1702 may be degraded. In particular, if the first terminal 1702 does not have the ability to remove cross-link interference, the degradation of performance may be even more severe.

[0187] To solve the above-mentioned cross-link interference problem between UEs, uplink and downlink signals in same-band full-duplex communication may be transmitted in different resource regions (e.g., time-frequency resource regions). For example, uplink and downlink signals transmitted in the same band (e.g., the same carrier) may be transmitted in different time resource regions. Alternatively, uplink and downlink signals transmitted in the same band (e.g., the same carrier) may be transmitted simultaneously (e.g., at the same time), and in this case, the uplink and downlink signals may be transmitted in different frequency regions.

[0188] FIG. 18 is a conceptual diagram showing an embodiment for explaining a method of multiplexing uplink and downlink signals in full-duplex communication.

[0189] 18, uplink signals and downlink signals within one serving cell (or carrier) may be multiplexed and transmitted using different resources (e.g., different time-frequency resources). For example, a first downlink signal 1801, a second downlink signal 1802 (or a first uplink signal 1803), and a second uplink signal 1804 may be transmitted using different time resources (i.e., time division multiplexing (TDM)). As another example, the first uplink signal 1803 and the second downlink signal 1802 may be transmitted using the same time resource but different frequency resources (i.e., frequency division multiplexing (FDM)).

[0190] The base station can receive the uplink signal and transmit a downlink signal. For example, the base station can transmit the second downlink signal to a terminal (e.g., a first terminal) and simultaneously receive the first uplink signal from another terminal (e.g., a second terminal). In this case, the second downlink signal can act as self-interference (or cross-link interference) in the base station's reception of the first uplink signal. Also, the first uplink signal can act as cross-link interference in the first terminal's reception of the second downlink signal. However, according to this embodiment, the frequency domains in which the first uplink signal is transmitted and the frequency domains in which the second downlink signal is transmitted can be separated from each other, and if the frequency domains are sufficiently far apart, the cross-link interference can be mitigated. Here, the first terminal and the second terminal can be the first terminal 1702 and the second terminal 1703 illustrated in FIG. 17, respectively.

[0191] In the embodiment of FIG. 18, the time interval during which simultaneous transmission of uplink and downlink signals is permitted as described above may be referred to as a sub-band full-duplex (SBFD) interval hereinafter.

[0192] In Rel-18, the start of 5G-Advanced, research is underway on full-duplex communication methods to increase frequency efficiency, improve uplink performance, and reduce latency. More specifically, a base station can perform transmission and reception simultaneously, while a mobile station can only perform either transmission or reception at a given time. Research is also underway on sub-band full-duplex (SBFD) communication methods, in which the frequency resources for uplink and downlink resources are separated from each other during the time period during which simultaneous transmission of uplink and downlink signals between a mobile station and a base station is permitted.

[0193] As illustrated in Figure 18, even when communication is performed using the SBFD scheme, the UE may lack or have insufficient capabilities to remove cross-link interference compared to the base station. Furthermore, in the case of a previous release UE (legacy UE) that does not support the SBFD scheme, the UE may not have the capability to remove cross-link interference from the start. Therefore, the present invention proposes an SBFD communication method that takes into consideration the UE's cross-link interference removal capabilities and coexistence with legacy UEs. More specifically, the present invention proposes an SBFD communication method for a time interval in which an SSB (synchronization signal block), one of downlink important signals, is transmitted (hereinafter referred to as "SSB time interval").

[0194] SSB is an important downlink signal that is measured during the initial connection process to perform cell search, time / frequency synchronization acquisition, cell reselection, and / or handover procedures. Therefore, not only legacy UEs but also UEs supporting SBFD communication need to receive SSB to perform the above-mentioned operations. Therefore, considering cross-link interference, it is preferable that the frequency domain for SBFD communication (hereinafter referred to as the SBFD frequency domain) be configured so as not to overlap with the frequency domain for SSB transmission (hereinafter referred to as the SSB frequency domain). However, considering resource efficiency, the time interval for SBFD communication (hereinafter referred to as the SBFD time interval) may be configured to overlap with the SSB transmission and reception interval (hereinafter referred to as the SSB time interval). Therefore, SBFD operation is required that takes into account the case where the SBFD time interval is configured to overlap with the SSB time interval.

[0195] As described above, SSB is used for various measurements not only during the initial connection procedure but also thereafter, so the UE must continuously monitor and measure SSB. Therefore, for accurate UE measurements, it is preferable that cross-link interference does not occur during the SSB time interval. To this end, if the SBFD time interval overlaps with the SSB time interval, SBFD operation may not be performed during the overlapping time interval. More specifically, even if uplink transmission within the SBFD frequency domain is scheduled for a UE supporting SBFD operation during the SBFD time interval, if the time interval for the corresponding uplink transmission overlaps with the SSB time interval, the UE may drop the corresponding uplink transmission without performing the corresponding uplink transmission. In this case, since cross-link interference due to SBFD operation does not occur during the SSB time interval, measurements for SSB may be performed more accurately. As described above, it is generally preferable that the SBFD frequency domain does not overlap with the SSB frequency domain. However, the embodiments proposed in the present invention may also be applied to cases where the SBFD frequency domain is configured to overlap with the SSB frequency domain.

[0196] Even when SBFD operation is not performed in an SSB time interval, whether to perform SBFD operation can be determined depending on whether SSBs are actually transmitted within the SSB time interval. As described with reference to Figures 8 and 9 in an NR communication system, some SSBs may not actually be transmitted within an SSB time interval (e.g., an SSB burst set), so the UE can determine whether to perform SBFD operation depending on whether SSBs are actually transmitted within an SSB time interval that overlaps with the SBFD time interval. More specifically, when an SSB time interval overlaps with an SBFD time interval, the UE does not perform SBFD operation if an SSB is actually transmitted within the overlapping time interval, and can perform SBFD operation if an SSB is not actually transmitted within the overlapping time interval.

[0197] In the present disclosure, the term "SSB time interval" is basically described with reference to Figures 8 and 9 and may refer to an SSB time interval (e.g., an SSB burst set) defined in a technical standard. For example, the SSB time interval may be understood as a concept corresponding to a half frame or a time interval within a half frame in which SSB(s) are transmitted, as defined in a 3GPP technical standard (e.g., TS38.213). Furthermore, if information regarding the position or interval in which SSB(s) are actually transmitted within the SSB time interval is indicated, the term "SSB time interval" in the present disclosure may be interpreted as the position or interval in which SSB(s) are actually transmitted within the SSB burst set.

[0198] Referring to Figures 8 and 9, information regarding the position(s) or period(s) at which the SSB(s) are actually transmitted at the SSB transmission possible positions within the aforementioned SSB time interval (e.g., SSB burst set) may be indicated to the terminal via RMSI and / or UE-specific RRC signaling (ssb-PositionsInBurst in ServingCellConfigCommonSIB or ServingCellConfigCommon), and in some frequency bands (e.g., FR2), the signaling method via RMSI and UE-specific RRC signaling may vary (e.g., 16 bits for RMSI, 64 bits for UE-specific RRC signaling).

[0199] Therefore, the UE can determine whether the corresponding information is applicable depending on whether information is acquired through RMSI or UE-specific RRC signaling. More specifically, if information on whether an SSB is actually transmitted is acquired only through RMSI, the UE can determine whether an SSB is actually transmitted within the SSB time interval based on the information through RMSI. If information on whether an SSB is actually transmitted is acquired only through UE-specific RRC signaling, the UE can determine whether an SSB is actually transmitted within the SSB time interval based on the information through UE-specific RRC signaling. On the other hand, if information on whether an SSB is actually transmitted is received through RMSI and UE-specific RRC signaling, and the information received through RMSI and the information received through UE-specific RRC signaling are identical, the UE can follow either of the two pieces of information. On the other hand, if the information received through RMSI and the information received through UE-specific RRC signaling are different, the UE preferably follows the information through UE-specific RRC signaling, which includes more detailed information.

[0200] In addition, SSB transmission period information can be additionally considered. Generally, SSBs for initial connection are transmitted with a basic period of 20 ms, but the base station can set the SSB transmission period within a range of 5 to 160 ms taking into account various environments. If a specific SSB transmission period is additionally set, the base station can determine whether to perform SBFD operation in the SSB transmission section by additionally considering the corresponding SSB transmission period. More specifically, if no additional SSB transmission period is set, the base station can determine whether to perform SBFD operation by assuming that SSBs are transmitted with a period of 20 ms and taking the corresponding period into account. If an SSB transmission period other than 20 ms is set, the base station can determine whether to perform SBFD operation by taking the set SSB transmission period into account.

[0201] As described above, the UE may not always perform SBFD operation during the SSB time interval. Alternatively, the UE may determine whether to perform SBFD operation depending on whether SSB is actually transmitted during the SSB time interval. The above-described operation can be selectively applied taking into account various system environments and can be set for each CC or BWP through system information or UE-specific RRC signaling, etc.

[0202] Meanwhile, in the present disclosure, the "SSB time interval" may be determined based on the configuration information of an SSB measurement window (e.g., an SSB-based RRM Measurement Timing Configuration (SMTC) window) received from the base station. In this case, the position or interval where the SSB(s) are actually transmitted may be interpreted as the "SSB time interval" based on information on the position or interval where the SSB(s) are actually transmitted, which is indicated to the terminal through RMSI and / or UE-specific RRC signaling.

[0203] As mentioned above, if SBFD operation is not performed in all SSB time intervals or is only performed in some SSB time intervals depending on the settings (SSB measurement window and whether or not actual SSB transmission is present), the benefits that can be obtained from supporting SBFD operation, such as improved uplink coverage and reduced latency, may not be significant due to frequent restrictions on SBFD operation depending on the SSB time interval.

[0204] Therefore, even if the SSB time interval and the SBFD time interval overlap, it may be preferable to support SBFD operation in the overlapping time interval in terms of resource efficiency. In this case, it is preferable to minimize cross-link interference that may affect other terminals performing measurements on SSB. Hereinafter, a method for reducing cross-link interference caused by SBFD operation will be described as another embodiment of the present invention.

[0205] Generally, in order to reduce cross-link interference caused by SBFD operation, a guard band may be set when configuring frequency domain resources for SBFD operation.

[0206] FIG. 19 is a conceptual diagram for explaining the setting of a frequency domain for SBFD operation according to one embodiment of the present invention.

[0207] 19, in order to reduce cross-link interference between frequency resources for the downlink and frequency resources for the uplink configured in a frequency domain 1901 for SBFD operation, a guard band may be configured around the frequency resources for the uplink. In the embodiment of FIG. 19, SBFD frequency domain 1901 is illustrated as including only uplink resources 1903 and guard bands 1904 and 1905, but the SBFD frequency domain may be defined as a domain including downlink resources, guard bands, and uplink resources. When configuring an SBFD frequency domain, cross-link interference caused by uplink transmissions of an SBFD-supporting terminal through uplink resources belonging to the SBFD frequency domain to downlink reception of other terminals may be reduced by configuring appropriate guard bands.

[0208] As described above, even when SBFD operation is performed in the SSB time interval, the impact on the SSB measurement performance of other terminals can be reduced through the use of guard bands. However, since reception of SSB is more important than reception of other downlink signals, in order to further reduce cross-link interference, the guard band set in the SBFD frequency domain in the SBFD time interval that overlaps with the SSB time interval can have a wider bandwidth than the guard band set in the SBFD frequency domain in the SBFD time interval that does not overlap with the SSB time interval.

[0209] Each guard band may be configured with a start resource block (RB) index and the number of RBs (or a start RB index and an end RB index) included in each guard band. Therefore, if a general guard band (e.g., a guard band configured in the SBFD frequency domain within an SBFD time interval that does not overlap with the SSB time interval) is configured to include M RBs, a guard band configured in the SBFD frequency domain within an SBFD time interval that overlaps with the SSB time interval may be configured to include N (>M) RBs.

[0210] FIG. 20 is a conceptual diagram illustrating a case where guard bands of different widths are set in the SSB time period and the general time period according to an embodiment of the present invention.

[0211] 20, a guard band (e.g., guard band #1) set in a time interval 2001 where the SBFD time interval and the SSB time interval overlap may be set to have a wider bandwidth than a guard band (e.g., guard band #2) set in a general time interval 2002. Therefore, a guard band set when the SSB time interval and the SBFD time interval overlap may relatively further reduce the impact of cross-link interference on downlink reception. As described above, a guard band taking into account the SSB time interval may be set and applied based on the slot in which the SSB is transmitted, or based on the symbol in which the SSB is transmitted, as shown in FIG.

[0212]

[0213] As described above, when different guard bands for SBFD operation are set for the SSB time period and the general time period, it is preferable that the base station performs appropriate uplink scheduling taking this into consideration. However, even in the case of configured grant (CG) scheduling or dynamic grant (DG) scheduling performed without considering the different guard bands, a UE uplink transmission method that takes this into consideration is required.

[0214] More specifically, if the uplink resources scheduled (allocated) to a terminal for uplink transmission belong to the uplink resources of the SBFD frequency domain during the general time interval but belong to the guard band of the SBFD frequency domain during the SSB time interval, the terminal can perform uplink transmission using the scheduled uplink resources during the general time interval. Conversely, the terminal can drop the corresponding uplink transmission during the SSB time interval or perform uplink transmission using only the remaining uplink resources of the assigned uplink resources excluding the frequency resources belonging to the guard band. In the latter case, the terminal can perform puncturing or rate matching on data mapped to the uplink resources belonging to the guard band. If the uplink resources scheduled (allocated) to a terminal for uplink transmission belong to the guard band of the SBFD frequency domain during the general time interval, the terminal can drop the corresponding uplink transmission even during the general time interval or perform uplink transmission using only the remaining uplink resources of the assigned uplink resources excluding the frequency resources belonging to the guard band. In the latter case, the terminal can perform puncturing or rate-matching on data mapped to uplink resources belonging to the guard band.

[0215] On the other hand, if the guard band(s) are set only to the symbol(s) where the SSB is transmitted, the width of the guard band may vary even within one slot. In this case, the UE may perform uplink transmission by considering only the larger guard band (i.e., the guard band set to the symbol(s) where the SSB is transmitted), or may perform uplink transmission by scheduling but perform puncturing or rate matching on data mapped to uplink resources belonging to the larger guard band area.

[0216]

[0217] In another embodiment, in addition to setting different guard band sizes for SBFD operation in the SSB time interval and the general time interval (the time interval in which downlink signals excluding SSB are received or uplink signals are transmitted), a method of applying different UL transmit powers to SBFD operation in the SSB time interval and the general time interval may be used. More specifically, in order to reduce the impact of cross-link interference on SSB measurements, it is preferable that the UL transmit power for SBFD operation performed in the SSB time interval be set lower than the UL transmit power for SBFD operation in the general time interval (including existing time intervals that do not support SBFD operation and / or positions where SSB is actually transmitted within the SSB time interval and intervals where SBFD operation is not performed).

[0218] JPEG2026504903000009.jpg72162

[0219]

[0220] SBFD operation (i.e., UL transmission operation) in the SSB time interval can be applied dynamically or semi-statically. The base station can dynamically or semi-statically signal to the terminal whether or not it supports SBFD operation based on cross-link interference, uplink beam(s), terminal location information, etc. acquired through the measurement process. DCI (e.g., 1-bit indication) can be used as dynamic signaling, and MAC CE or RRC signaling can be used as semi-static signaling.

[0221] As another alternative, the UE can determine whether to support SBFD operation based on the priority of the SSB reception operation without any additional signaling. For example, even if SBFD operation is configured to be supported during the SSB time interval, in the case of a high-priority SSB reception operation (e.g., measurement for initial connection or cell reselection), uplink transmission through SBFD operation can be dropped and only SSB reception operation can be performed. Alternatively, in the case of a high-priority uplink transmission (e.g., URLLC transmission), uplink transmission through SBFD operation can be performed regardless of the SSB transmission interval.

[0222] Alternatively, a list of Transmission Configuration Indicators (TCIs) or SRS resource indicators (SRIs) prohibited in the SSB time interval may be signaled to the UE. The UE may consider the remaining TCIs (or SRIs) in the UL TCI pool (or SRI pool) that are not included in the list of TCIs or SRIs prohibited in the SSB transmission interval as valid TCIs (or SRIs), and may perform only uplink transmissions to which valid TCIs (or SRIs) are applied in the SSB time interval. More specifically, if the uplink scheduling information received by the UE includes indication information for a TCI (or SRI), or if the CG configuration information for a configured grant (CG)-scheduled uplink transmission includes indication information for a TCI (or SRI), the UE may perform scheduled uplink transmissions in the SSB time interval if the corresponding indication information indicates a valid TCI (or SRI).

[0223]

[0224] As described above, in order to eliminate or reduce the effects of cross-link interference during various procedures and measurement processes via SSB, it may be preferable to not support SBFD operation in the SSB time interval, or to set a larger guard band for SBFD operation performed in the SSB time interval even if SBFD operation is supported in the SSB time interval. Additionally or alternatively, separate power control may be applied for SBFD operation performed in the SSB time interval. Furthermore, whether SBFD operation is supported may be dynamically or semi-statically configured through signaling.

[0225] SSBs can be divided into cell-defining (CD)-SSBs, which are used in the cell search and initial connection processes, and non-cell-defining (NCD)-SSBs, which are primarily used for time / frequency synchronization and measurement. Because CD-SSBs are essential for the cell search and initial connection processes, receiving and measuring CD-SSBs may be more important than NCD-SSBs. Therefore, as described above, it may be undesirable from the perspective of resource efficiency to not support SBFD operation for all SSB time intervals without distinguishing between CD-SSBs and NCD-SSBs, to configure a guard band with a different size (e.g., a larger guard band) than the guard band for general time intervals, to apply separate power control, or to dynamically or semi-statically configure whether or not SBFD operation is supported. Therefore, it may be preferable to apply different SBFD resource configurations and whether or not SBFD operation is supported depending on the CD-SSB time interval and the NCD-SSB time interval.

[0226] More specifically, SBFD operation may not be supported in the CD-SSB time interval, but may be supported only in the NCD-SSB time interval. For SBFD operation performed in the NCD-SSB time interval, it may be configured whether or not a large guard band is set, whether or not separate power control is applied, and / or whether or not dynamic or semi-static SBFD operation is supported. For example, the same guard band as in the general time interval may be applied to the NCD-SSB time interval, the same power control as in the general time interval may be applied, or dynamic or semi-static SBFD operation may not be supported.

[0227] The above-described embodiments have described an SBFD communication method taking SSB into consideration, but the SBFD communication method described in the above-described embodiments may also be applied to a PDCCH transmitted in a Type 0 PDCCH CSS that is one-to-one mapped to CD-SSB and transmitted, and an RMSI PDSCH scheduled through the PDCCH CSS.

[0228]

[0229] Hereinafter, an embodiment of the present invention will be described in more detail. Figure 21, which will be described later, corresponds to an embodiment of SBFD operation taking into account SSB transmission during an initial connection process, and Figure 22, which will be described later, corresponds to an embodiment of SBFD operation taking into account SSB transmission during an SSB measurement process.

[0230] FIG. 21 is a flowchart illustrating a method for performing SBFD operation taking into account SSB transmission according to one embodiment of the present invention.

[0231] 21, the terminal 2102 may identify an SSB time interval for SSB reception or measurement and a general time interval other than the SSB time interval (S2110). Here, the SSB time interval may be predefined by a technical standard (e.g., the SSB burst set described with reference to FIGS. 8 and 9) or may be determined as the position(s) or interval(s) where the actual SSB(s) are transmitted within the SMTC window or SSB burst set identified based on RMSI (remaining system information) and / or UE-specific RRC signaling received from the base station 2101.

[0232] Next, the terminal can receive or measure at least one SSB from the base station 2101 during the SSB time interval (S2120), and can transmit at least one uplink signal or receive at least one downlink signal during the general time interval (S2130).

[0233] 21 shows that the terminal 2102 receives an SSB from the base station 2101 after performing step S2110 of identifying the SSB time interval and the general time interval. However, the terminal 2102 may attempt to receive an SSB during the initial connection process and identify the SSB time interval based on the received SSB. That is, since the terminal 2102 is unaware of the existence of an SSB before performing the initial connection, the terminal 2102 can identify the SSB time interval through reception of the SSB and can identify the time interval excluding the identified SSB time interval as the general time interval.

[0234] The terminal 2102 and the base station 2101 can perform SBFD operations in the SSB time interval and the general time interval, or can perform SBFD operations only in the general time interval without performing SBFD operations in the SSB time interval (S2140).

[0235] Meanwhile, when SBFD operation is performed in the SSB time interval, a first guard band for the SBFD operation applied to the SSB time interval and a second guard band for the SBFD operation applied to the general time interval may be set separately. That is, the first guard band and the second guard band may be defined by separate parameters (or formulas), or may be defined by either the first guard band or the second guard band and an offset between the first and second guard bands. For example, the first guard band for the SBFD operation applied to the SSB time interval may be set to have a wider bandwidth than the second guard band for the SBFD operation applied to the general time interval.

[0236] Meanwhile, when SBFD operation is performed in the SSB time interval, the uplink transmission power for the SBFD operation applied to the SSB time interval (first transmission power) and the uplink transmission power for the SBFD operation applied to the general time interval (second transmission power) can be set separately. That is, the first transmission power and the second transmission power can be defined by separate parameters (or equations), or can be defined by either one of the first transmission power and the second transmission power and an offset between the first transmission power and the second transmission power. For example, the first transmission power can be set to have a lower value than the second transmission power.

[0237] In addition, the terminal 2102 may additionally receive a list including at least one Transmission Configuration Indicator (TCI) or SRS resource indicator (SRI) prohibited in the SSB time interval from the base station 2101. In this case, if SBFD operation is performed in the SSB time interval, the terminal 2102 may not perform uplink transmission to which the at least one TCI or SRI is applied during the SSB time interval.

[0238] The SSB time interval may be divided into a CD-SSB time interval in which cell-defining (CD)-SSB(s) are transmitted and / or an NCD-SSB time interval in which non-cell-defining (NCD)-SSB(s) are transmitted. When SBFD operation is performed in the SSB time interval, a first guard band for the SBFD operation applied to the CD-SSB time interval and a second guard band for the SBFD operation applied to the NCD-SSB time interval may be set separately. Additionally or alternatively, an uplink transmit power (first transmit power) for the SBFD operation applied to the CD-SSB time interval and an uplink transmit power (second transmit power) for the SBFD operation applied to the NCD-SSB time interval may be set separately. In this case, the first and second guard bands and the first and second transmit powers may be set as described above.

[0239] FIG. 22 is a flowchart illustrating a method for performing SBFD operation taking into account SSB transmission according to another embodiment of the present invention.

[0240] 22, the terminal 2202 may receive configuration information for an SSB time interval for performing SSB reception or measurement from the base station 2201 (S2210). In this case, the configuration information for the SSB time interval may be received as SSB measurement window configuration information, or may be received based on the SSB measurement window configuration information and remaining system information (RMSI) and / or UE-specific RRC signaling. The SSB time interval may be determined by the SSB measurement window indicated by the SSB measurement window configuration information, or may be determined as the position(s) or interval(s) where the SSB(s) are actually transmitted within the SSB measurement window indicated by the RMSI and / or UE-specific RRC signaling.

[0241] In addition, the terminal 2202 may receive configuration information for the terminal's SBFD operation from the base station 2201 (S2220). For example, the configuration information regarding the SBFD operation may include resource configuration for the SBFD operation (described below with reference to FIGS. 19 and 20) and / or information indicating whether or not to perform the SBFD operation. Meanwhile, if the configuration information regarding the SBFD operation is predefined by a technical standard or has already been transmitted to the terminal in a different form of information, step S2220 may be omitted. Also, prior to step S2220, the terminal 2202 may perform a procedure of reporting capability information to the base station 2201 indicating that the terminal 2202 has the capability to support the SBFD operation; however, this procedure is omitted in FIG. 22 for convenience of explanation. Also, although FIG. 22 illustrates the step S2220 being performed after the step S2210, the step S2220 may be performed before or simultaneously with the step S2210.

[0242] Next, the terminal 2202 determines whether to perform SBFD operation in the SSB time interval (S2230), and if it is determined to perform the SBFD operation in the SSB time interval, it can perform the SBFD operation together with the base station 2201 in the SSB time interval (S2240).

[0243] When the SBFD operation is performed in the SSB time interval, first guard band(s) may be configured around uplink resources belonging to a frequency domain for performing the SBFD operation within the SSB time interval. The bandwidth of the first guard band(s) and the bandwidth of second guard band(s) configured around uplink resources belonging to a frequency domain for performing the SBFD operation in a general time interval that does not overlap with the SSB time interval may be configured separately. That is, the first and second guard bands may be defined by separate parameters (or equations), or may be defined by one of the first and second guard bands and an offset between the first and second guard bands. For example, the first guard band for the SBFD operation applied to the SSB time interval may be configured to have a wider bandwidth than the second guard band for the SBFD operation applied to the general time interval.

[0244] When uplink transmission is scheduled through uplink resources including the first guard band(s), the terminal can either abandon the uplink transmission or perform the uplink transmission using resources other than the resources belonging to the first guard band(s).When the uplink transmission is performed using resources other than the resources belonging to the first guard band(s), the terminal can perform puncturing or rate-matching on uplink transmission data mapped to resources belonging to the first guard band(s).

[0245] When the SBFD operation is performed in the SSB time interval, a transmission power (hereinafter, referred to as a first transmission power) applied to uplink resources belonging to a frequency domain for performing the SBFD operation within the SSB time interval and a transmission power (hereinafter, referred to as a second transmission power) applied to uplink resources belonging to a frequency domain for performing the SBFD operation in a general time interval that does not overlap with the SSB time interval may be set separately. That is, the first transmission power and the second transmission power may be defined by separate parameters (or equations), or may be defined by one of the first transmission power and the second transmission power and an offset between the first transmission power and the second transmission power. For example, the first transmission power may be set to have a lower value than the second transmission power.

[0246] Meanwhile, the terminal 2202 may additionally receive a list including at least one Transmission Configuration Indicator (TCI) or SRS resource indicator (SRI) prohibited in the SSB time interval from the base station 2201. In this case, if SBFD operation is performed in the SSB time interval, the terminal 2202 may not perform uplink transmission to which the at least one TCI or SRI is applied during the SSB time interval.

[0247] The SSB time interval may be divided into a CD-SSB time interval in which cell-defining (CD)-SSB(s) are transmitted and / or an NCD-SSB time interval in which non-cell-defining (NCD)-SSB(s) are transmitted. When SBFD operation is performed in the SSB time interval, a first guard band for the SBFD operation applied to the CD-SSB time interval and a second guard band for the SBFD operation applied to the NCD-SSB time interval may be set separately. Additionally or alternatively, an uplink transmit power (first transmit power) for the SBFD operation applied to the CD-SSB time interval and an uplink transmit power (second transmit power) for the SBFD operation applied to the NCD-SSB time interval may be set separately. In this case, the first and second guard bands and the first and second transmit powers may be set as described above.

[0248] Meanwhile, in another embodiment, a terminal supporting SBFD operation can receive configuration information for a separate SSB measurement window (second SSB measurement window) for determining whether to perform SBFD operation, in addition to configuration information for a general SSB measurement window (first SSB measurement window). For example, a separate SSB measurement window (e.g., SMTC window) for SBFD operation can be configured for the terminal from the base station through SSB-MTC (e.g., SSB-MRC5). In this case, the terminal can perform measurements on SSB(s) only within the separately configured second SSB measurement window.

[0249] In addition, the UE may determine whether to perform SBFD operation depending on whether SSBs are actually transmitted even within a separately set second SSB measurement window, and may perform SBFD operation in time intervals where SSBs are not actually transmitted. In this case, information on the position(s) and interval(s) where SSBs are not actually transmitted may be determined based on the remaining system information (RMSI) received from the base station and / or the ssb-PositionsInBurst parameter received through UE-specific radio resource control (RRC) signaling, as described above.

[0250] In addition, the terminal can perform SBFD operations in other SSB time intervals (i.e., time intervals that belong to the first SSB measurement window but not the second SSB measurement window) regardless of whether SSBs are actually transmitted or not.

[0251]

[0252] The operations of the methods according to the embodiments of the present invention may be embodied as a computer-readable program or code stored in a computer-readable recording medium. The computer-readable recording medium includes all types of storage devices that store information that can be read by a computer system. The computer-readable recording medium may also be distributed across computer systems connected to a network, so that the computer-readable program or code may be stored and executed in a distributed manner.

[0253] Additionally, the computer-readable recording medium may include a hardware device specially configured to store and execute program instructions, such as a ROM, RAM, flash memory, etc. The program instructions may include not only machine language code, such as that produced by a compiler, but also high-level language code that can be executed by a computer using an interpreter, etc.

[0254] Although some aspects of the invention have been described in the context of an apparatus, they may also be described in terms of a corresponding method, where a block or apparatus corresponds to a method step or feature of a method step. Similarly, aspects described in the context of a method may also be described in terms of a corresponding block or item or feature of a corresponding apparatus. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or electronic circuitry. In some embodiments, at least one or more of the most significant method steps may be performed by such a device.

[0255] In some embodiments, a programmable logic device (e.g., a field programmable gate array) may be used to perform some or all of the functions of the methods described herein. In some embodiments, a field programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described herein. In general, it is preferred that the methods be performed by some hardware device.

[0256] Although the present invention has been described above with reference to preferred embodiments, it will be understood by those skilled in the art that various modifications and variations of the present invention may be made without departing from the spirit and scope of the present invention as set forth in the following claims.

Claims

1. 1. A method of a terminal, comprising: Identifying an SSB (synchronization signal block) time interval for receiving or measuring an SSB and a general time interval other than the SSB time interval; receiving or measuring at least one SSB during the SSB time interval; and transmitting at least one uplink signal and receiving at least one downlink signal during the common time interval; A method in which a subband full duplex (SBFD) operation is performed in the SSB time interval and the general time interval, or the SBFD operation is not performed in the SSB time interval but is performed only in the general time interval.

2. 2. The method of claim 1, wherein the SSB time interval is determined by an SSB burst set predefined by a technical standard, or is determined by a position or interval in which SSB(s) are actually transmitted within the SMTC window or the SSB burst set determined based on remaining system information (RMSI) and / or UE-specific RRC signaling received from the base station.

3. 2. The method of claim 1, wherein, when an SBFD operation is performed in the SSB time interval, a first guard band for the SBFD operation applied to the SSB time interval and a second guard band for the SBFD operation applied to the general time interval are separately set.

4. The method of claim 1, wherein when an SBFD operation is performed in the SSB time interval, an uplink transmission power for the SBFD operation applied to the SSB time interval and an uplink transmission power for the SBFD operation applied to the general time interval are set separately.

5. The method may further include receiving a list from a base station, the list including at least one Transmission Configuration Indicator (TCI) or SRS resource indicator (SRI) that is prohibited during the SSB time interval; The method of claim 1, wherein, when an SBFD operation is performed in the SSB time interval, the terminal does not perform uplink transmission to which the at least one TCI or SRI is applied during the SSB time interval.

6. The SSB time interval is divided into a CD-SSB time interval in which cell-defining (CD)-SSB(s) are transmitted and / or an NCD-SSB time interval in which non-cell-defining (NCD)-SSB(s) are transmitted. When an SFBD operation is performed in the SSB time interval, The first guard band for the SBFD operation applied to the CD-SSB time period and the second guard band for the SBFD operation applied to the NCD-SSB time period are set separately or The method of claim 1, wherein an uplink transmit power for the SBFD operation applied to the CD-SSB time interval and an uplink transmit power for the SBFD operation applied to the NCD-SSB time interval are set separately.

7. 1. A method of a terminal, comprising: receiving, from a base station, setting information of an SSB (synchronization signal block) time interval for receiving or measuring an SSB; receiving configuration information regarding a subband full duplex (SBFD) operation from the base station; determining whether to perform the SBFD operation in the SSB time interval; and When it is determined to perform the SBFD operation in the SSB time period, performing the SBFD operation in the SSB time period.

8. The SSB time interval configuration information is received as SSB measurement window configuration information or is received based on the SSB measurement window configuration information and remaining system information (RMSI) and / or UE-specific RRC signaling; The method of claim 7, wherein the SSB time interval is determined by an SSB measurement window indicated by the SSB measurement window setting information, or is determined by a position(s) or interval(s) in which SSB(s) are actually transmitted within the SSB measurement window indicated by the RMSI and / or UE-specific RRC signaling.

9. The method of claim 7, further comprising the step of performing the SBFD operation in a general time interval other than the SSB time interval.

10. 8. The method of claim 7, wherein, when the SBFD operation is performed in the SSB time interval, first guard band(s) are set around uplink resources belonging to a frequency domain for performing the SBFD operation within the SSB time interval.

11. The method of claim 10, wherein the bandwidth of the second guard band(s) is set around uplink resources belonging to a frequency domain for performing the SBFD operation in a general time interval that does not overlap with the bandwidth of the first guard band(s) and the SSB time interval, and the bandwidth of the second guard band(s) is set separately.

12. 11. The method of claim 10, wherein, when uplink transmission through uplink resources including the first guard band(s) is scheduled, the terminal abandons the uplink transmission or performs the uplink transmission using resources excluding resources belonging to the first guard band(s) in the uplink resources.

13. 13. The method of claim 12, wherein, when the uplink transmission is performed using resources other than resources belonging to the first guard band(s) in the uplink resources, the terminal performs puncturing or rate matching on uplink transmission data mapped to resources belonging to the first guard band(s).

14. 8. The method of claim 7, wherein, when the SBFD operation is performed in the SSB time interval, a transmit power applied to uplink resources belonging to a frequency domain for performing the SBFD operation within the SSB time interval and a transmit power applied to uplink resources belonging to a frequency domain for performing the SBFD operation in a general time interval that does not overlap with the SSB time interval are set separately.

15. The method may further include receiving a list from a base station, the list including at least one Transmission Configuration Indicator (TCI) or SRS resource indicator (SRI) that is prohibited during the SSB time interval; The method of claim 7, wherein, when an SBFD operation is performed in the SSB time interval, the terminal does not perform uplink transmission to which the at least one TCI or SRI is applied during the SSB time interval.

16. The SSB time interval is divided into a CD-SSB time interval in which cell-defining (CD)-SSB(s) are transmitted and / or an NCD-SSB time interval in which non-cell-defining (NCD)-SSB(s) are transmitted. When an SFBD operation is performed in the SSB time interval, The first guard band for the SBFD operation applied to the CD-SSB time period and the second guard band for the SBFD operation applied to the NCD-SSB time period are set separately or The method of claim 7, wherein an uplink transmit power for the SBFD operation applied to the CD-SSB time interval and an uplink transmit power for the SBFD operation applied to the NCD-SSB time interval are set separately.

17. 1. A method of a terminal, comprising: receiving setting information of a first SSB measurement window from a base station; receiving configuration information regarding SBFD operation from the base station; receiving second SSB measurement window setting information from the base station; performing a measurement operation on SSB(s) in a first SSB time interval belonging to the second SSB measurement window; and performing the SBFD operation in a time interval that belongs to the first SSB measurement window and does not belong to the second SSB measurement window.

18. The method according to claim 17, wherein the first SSB measurement window setting information and the second SSB measurement window setting information are each SMTC (SSB-based RRM Measurement Timing Configuration) window setting information.

19. The method may further include determining whether to perform the SBFD operation in the first SSB time period, wherein the determining whether to perform the SBFD operation in the first SSB time period comprises: receiving information on the position(s) at which the SSB(s) are actually transmitted from the base station among the SSB transmittable positions within the first SSB time period; determining whether to perform the SBFD operation at positions other than positions where SSB(s) are actually transmitted among SSB transmittable positions within the first SSB time period; and The method of claim 17, further comprising: performing the SBFD operation in the first SSB time period when it is determined to perform the SBFD operation in the first SSB time period.

20. 20. The method of claim 19, wherein information on the position(s) at which the SSB(s) are actually transmitted among the SSB transmittable positions within the first SSB time interval is remaining system information (RMSI) and / or an ssb-PositionsInBurst parameter received from the base station through terminal-specific radio resource control (RRC) signaling.

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