Radio link monitoring method and device for variable ssb in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. The present disclosure provides a method and a device for energy saving in a wireless communication system.

Description

Radio link monitoring method and device for variable SSB in a wireless communication system

[0001] The present disclosure relates to the operation of a terminal and a base station in a wireless communication system. Specifically, the present disclosure relates to a method and apparatus for energy saving in a wireless communication system.

[0002] 5G mobile communication technology defines a wide frequency band to enable fast transmission speeds and new services, and can be implemented not only in frequency bands below 6 GHz ('Sub 6 GHz'), such as 3.5 gigahertz (3.5 GHz), but also in ultra-high frequency bands called millimeter waves (mmWave), such as 28 GHz and 39 GHz ('Above 6 GHz'). In addition, for 6G mobile communication technology, which is referred to as a system beyond 5G, implementation in the terahertz band (e.g., the 3 terahertz (3 THz) band at 95 GHz) is being considered to achieve transmission speeds 50 times faster and ultra-low latency reduced to one-tenth compared to 5G mobile communication technology.

[0003] In the early stages of 5G mobile communication technology, aiming to satisfy service support and performance requirements for enhanced Mobile BroadBand (eMBB), Ultra-Reliable Low-Latency Communications (URLLC), and massive Machine-Type Communications (mMTC), technologies such as beamforming and Massive MIMO to mitigate path loss and increase transmission distance in ultra-high frequency bands, support for various numerologies (such as the operation of multiple subcarrier spacings) and dynamic operation of slot formats for the efficient utilization of ultra-high frequency resources, initial access techniques to support multi-beam transmission and broadband, definition and operation of Band-Width Parts (BWP), Low Density Parity Check (LDPC) codes for high-volume data transmission, new channel coding methods such as Polar Codes for the reliable transmission of control information, and L2 pre-processing (L2 Standardization has been carried out for pre-processing, network slicing which provides a dedicated network specialized for specific services, and other methods.

[0004] Currently, discussions are underway to improve and enhance the performance of the initial 5G mobile communication technology, taking into account the services that the 5G mobile communication technology was intended to support. Additionally, standardization of the physical layer is in progress for technologies such as V2X (Vehicle-to-Everything), which helps autonomous vehicles make driving decisions and enhance user convenience based on their own location and status information transmitted by the vehicle; NR-U (New Radio Unlicensed), which aims for system operation in unlicensed bands to comply with various regulatory requirements; NR terminal low power consumption technology (UE Power Saving); Non-Terrestrial Network (NTN), which is direct terminal-satellite communication for securing coverage in areas where communication with the terrestrial network is impossible; and positioning.

[0005] In addition, standardization is underway in the field of wireless interface architecture / protocols for technologies such as the Industrial Internet of Things (IIoT) for supporting new services through linkage and convergence with other industries, Integrated Access and Backhaul (IAB) which provides nodes for expanding network service areas by integrating wireless backhaul links and access links, Mobility Enhancement including Conditional Handover and Dual Active Protocol Stack (DAPS) Handover, and 2-step Random Access (2-step RACH for NR) which simplifies random access procedures. Standardization is also underway in the field of system architecture / services for 5G baseline architectures (e.g., Service based Architecture, Service based Interface) for incorporating Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC), which provides services based on the location of the terminal.

[0006] When such 5G mobile communication systems are commercialized, connected devices, which are increasing explosively, will be connected to communication networks. Accordingly, it is expected that there will be a need to enhance the functionality and performance of 5G mobile communication systems and to integrate the operation of connected devices. To this end, new research is planned to be conducted on 5G performance improvement and complexity reduction, support for AI services, support for metaverse services, and drone communication using eXtended Reality (XR), Artificial Intelligence (AI), and Machine Learning (ML) to efficiently support Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR).

[0007] Furthermore, the advancement of these 5G mobile communication systems encompasses multi-antenna transmission technologies such as new waveforms to guarantee coverage in the terahertz band of 6G mobile communication technology, Full Dimensional MIMO (FD-MIMO), array antennas, and large-scale antennas; metamaterial-based lenses and antennas to improve terahertz band signal coverage; high-dimensional spatial multiplexing technology using OAM (Orbital Angular Momentum); and Reconfigurable Intelligent Surface (RIS) technology; as well as Full Duplex technology for enhancing frequency efficiency and system networks in 6G mobile communication technology; AI-based communication technologies that realize system optimization by utilizing satellites and AI from the design stage and internalizing end-to-end AI support functions; and the realization of services of complexity exceeding the limits of terminal computing capabilities by utilizing ultra-high-performance communication and computing resources. It could serve as a foundation for the development of next-generation distributed computing technologies.

[0008] With the recent development of 5G / 6G communication systems that take the environment into account, there is a growing need for methods to reduce energy consumption or save energy in communication systems (e.g., terminals, base stations, networks, etc.).

[0009] Embodiments of the present disclosure aim to provide an apparatus and method capable of effectively providing mobile communication services. Specifically, a method for monitoring a radio link for an SSB when adjusting the SSB transmission cycle is provided.

[0010] The technical problems to be solved in the disclosed embodiments are not limited to those mentioned above, and other unmentioned technical problems may be considered by those skilled in the art from the various embodiments of the present disclosure described below.

[0011] The present disclosure, for solving the above-mentioned problems, comprises a method performed by a terminal in a wireless communication system, the method comprising: receiving an SSB setting including a plurality of periods for changing an SSB (synchronization signal block) from a base station; receiving information from the base station instructing the change of the SSB, wherein the information instructing the change of the SSB includes a field instructing one of the plurality of periods; and, when the period instructed by the field is greater than or equal to a threshold value, performing radio link monitoring based on the SSB received according to the instructed period.

[0012] In addition, the present disclosure for solving the above-mentioned problems comprises a method performed by a base station in a wireless communication system, comprising: transmitting an SSB setting including a plurality of periods for changing an SSB (synchronization signal block) to a terminal; transmitting information instructing the terminal to change the SSB, wherein the information instructing the change the SSB includes a field instructing one of the plurality of periods; and transmitting an SSB based on the period instructed by the field, wherein radio link monitoring is performed based on the SSB when the instructed period is greater than or equal to a threshold value.

[0013] In addition, the present disclosure for solving the above-mentioned problems comprises, in a terminal of a wireless communication system, at least one transceiver; at least one processor connected to communicate with the at least one transceiver; and a memory connected to communicate with the at least one processor and executable individually or in any combination thereof, wherein the terminal receives an SSB setting including a plurality of periods for changing an SSB (synchronization signal block) from a base station, receives information from the base station instructing the SSB change, wherein the information instructing the SSB change includes a field indicating one of the plurality of periods, and, when the period indicated by the field is greater than or equal to a threshold value, stores a command to perform radio link monitoring based on the SSB received according to the indicated period.

[0014] Furthermore, the present disclosure for solving the above-mentioned problems comprises, in a base station of a wireless communication system, at least one transceiver; at least one processor connected to the at least one transceiver so as to be able to communicate with the at least one transceiver; and a memory connected to the at least one processor so as to be able to communicate with the at least one processor and capable of executing the at least one processor individually or in any combination thereof, wherein the base station transmits an SSB setting including a plurality of periods for changing an SSB (synchronization signal block) to a terminal, transmits information instructing the terminal to change the SSB, and the information instructing the change the SSB includes a field indicating one of the plurality of periods; and a memory storing an instruction to transmit an SSB based on the period indicated by the field, wherein radio link monitoring is performed based on the SSB when the indicated period is greater than or equal to a threshold value.

[0015] An embodiment of the present disclosure provides a method for monitoring a radio link when adjusting the SSB transmission cycle in a mobile communication system. Specifically, according to at least one embodiment of the present disclosure, a terminal can efficiently monitor a radio link even when a base station adjusts the SSB transmission cycle.

[0016] The effects obtainable from the disclosed embodiments are not limited to those mentioned above, and other unmentioned effects can be clearly derived and understood by a person skilled in the art based on the following detailed description.

[0017] FIG. 1 illustrates the basic structure of the time-frequency domain, which is a wireless resource domain in a wireless communication system according to one embodiment of the present disclosure.

[0018] FIG. 2 illustrates a slot structure considered in a wireless communication system according to one embodiment of the present disclosure.

[0019] FIG. 3 illustrates an example of a time domain mapping structure of a synchronization signal and a beam sweeping operation according to one embodiment of the present disclosure.

[0020] FIG. 4 illustrates a synchronization signal block considered in a wireless communication system according to one embodiment of the present disclosure.

[0021] FIG. 5 illustrates various transmission cases of a synchronization signal block in a frequency band below 6 GHz considered in a wireless communication system according to one embodiment of the present disclosure.

[0022] FIG. 6 illustrates transmission cases of a synchronization signal block in a frequency band of 6 GHz or higher considered in a wireless communication system according to one embodiment of the present disclosure.

[0023] FIG. 7 illustrates transmission cases of a synchronization signal block according to a subcarrier interval within 5ms in a wireless communication system according to one embodiment of the present disclosure.

[0024] FIG. 8 illustrates an example explaining DMRS patterns (type 1 and type 2) used for communication between a base station and a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0025] FIG. 9 illustrates an example of channel estimation using DMRS received from one PUSCH in the time band of a wireless communication system according to one embodiment of the present disclosure.

[0026] FIG. 10 illustrates a method for resetting SSB transmission through dynamic signaling of a wireless communication system according to one embodiment of the present disclosure.

[0027] FIG. 11 illustrates a method for resetting BWP and BW through dynamic signaling of a wireless communication system according to one embodiment of the present disclosure.

[0028] FIG. 12 illustrates a method for resetting DRX through dynamic signaling of a wireless communication system according to one embodiment of the present disclosure.

[0029] FIG. 13 illustrates an example explaining a DTx method for base station energy saving according to one embodiment of the present disclosure.

[0030] FIG. 14 illustrates an example explaining the operation of a base station according to a gNB wake-up signal according to one embodiment of the present disclosure.

[0031] FIG. 15 illustrates an antenna adaptation method for a base station for energy saving of a wireless communication system according to one embodiment of the present disclosure.

[0032] FIG. 16 is a diagram illustrating an example of on-demand SSB operation in a situation where an S-cell (secondary cell, SCell) is set up for a terminal but is not yet activated, according to one embodiment of the present disclosure.

[0033] FIG. 17 is a diagram illustrating an example of on-demand SSB operation in a situation where an activation instruction for an S-cell (secondary cell, SCell) is received according to an embodiment of the present disclosure.

[0034] FIG. 18 is a diagram illustrating an example in which an adaptation of the SSB burst cycle is applied according to one embodiment of the present disclosure.

[0035] FIG. 19 is a flowchart of the operation of a terminal applying an energy saving method of a wireless communication system according to one embodiment of the present disclosure.

[0036] FIG. 20 is a flowchart of the operation of a base station applying an energy saving method of a wireless communication system according to one embodiment of the present disclosure.

[0037] FIG. 21 is a block diagram of a terminal according to one embodiment of the present disclosure.

[0038] FIG. 22 is a block diagram of a base station according to one embodiment of the present disclosure.

[0039] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0040] In describing the embodiments of the present disclosure below, technical details that are well known in the technical field to which the present disclosure belongs and are not directly related to the present disclosure are omitted. This is intended to convey the essence of the present disclosure more clearly without obscuring it by omitting unnecessary explanations.

[0041] For the same reason, some components in the attached drawings have been exaggerated, omitted, or schematically depicted. Additionally, the dimensions of each component do not entirely reflect their actual dimensions. Identical or corresponding components in each drawing have been assigned the same reference numbers.

[0042] The advantages and features of the present disclosure and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments described below but may be implemented in various different forms. These embodiments are provided merely to ensure that the present disclosure is complete and to fully inform those skilled in the art of the scope of the technical concept to which the present disclosure pertains, and the present disclosure is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same components. Furthermore, the terms described below are defined considering their functions in the present disclosure, and these may vary depending on the intentions or conventions of the user or operator. Therefore, their definitions should be based on the content throughout the present specification.

[0043] Hereinafter, the base station is an entity that performs resource allocation for terminals and may be at least one of gNode B, eNode B, Node B, BS (Base Station), wireless access unit, base station controller, or a node on a network. The terminal may include UE (user equipment), MS (mobile station), cellular phone, smartphone, computer, or a multimedia system capable of performing communication functions. In this disclosure, the downlink (DL) refers to the wireless transmission path of a signal transmitted by the base station to the terminal, and the uplink (UL) refers to the wireless transmission path of a signal transmitted by the terminal to the base station.

[0044] In addition, while LTE or LTE-A systems may be described below as examples, embodiments of the present disclosure may also be applied to other communication systems having similar technical backgrounds or channel types. For example, 5th generation mobile communication technologies (5G, new radio, NR) developed after LTE-A may be included, and the 5G below may be a concept that includes existing LTE, LTE-A, and other similar services. Furthermore, the present disclosure may be applied to other communication systems with some modifications made at the discretion of a person with skilled technical knowledge, without significantly departing from the scope of the present disclosure.

[0045] At this point, it will be understood that each block of the process flow diagrams and combinations of the flow diagrams can be executed by computer program instructions. Since these computer program instructions can be loaded into the processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, the instructions executed through the processor of the computer or other programmable data processing equipment create means to perform the functions described in the flow diagram block(s). Since these computer program instructions can also be stored in computer-available or computer-readable memory that can be directed toward the computer or other programmable data processing equipment to implement the function in a specific way, the instructions stored in computer-available or computer-readable memory can also produce a manufactured item containing instruction means to perform the function described in the flow diagram block(s). Since computer program instructions can be loaded onto a computer or other programmable data processing equipment, instructions that perform a series of operation steps on the computer or other programmable data processing equipment to create a process executed by the computer can also provide steps for executing the functions described in the flowchart block(s).

[0046] Additionally, each block may represent a module, segment, or part of code containing one or more executable instructions for executing a specific logical function(s). It should also be noted that in some alternative execution examples, the functions mentioned in the blocks may occur out of order. For example, two blocks described in succession may actually be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order according to their corresponding functions.

[0047] As used in this disclosure, the term “part” refers to a software or hardware component, such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC), and the “part” performs certain roles. However, the “part” is not limited to software or hardware. The “part” may be configured to reside in an addressable storage medium or configured to run one or more processors. Thus, by example, the “part” includes components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and “parts” may be combined into a smaller number of components and “parts” or further separated into additional components and “parts.” In addition, the components and '~parts' may be implemented to utilize one or more CPUs within the device or secure multimedia card. Also, in the embodiment, the '~part' may include one or more processors.

[0048] The methods and devices proposed in the embodiments of the present disclosure below are not limited to each specific embodiment, and may also be utilized as a combination of all or part of one or more embodiments proposed in the disclosure. Accordingly, the embodiments of the present disclosure may be applied with some modifications within the scope of the present disclosure without significantly departing from the scope of the present disclosure, at the judgment of a person skilled in the art.

[0049] Wireless communication systems are evolving from providing early voice-oriented services to broadband wireless communication systems that provide high-speed, high-quality packet data services, such as 3GPP’s HSPA (high speed packet access), LTE (long term evolution or E-UTRA (evolved universal terrestrial radio access)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2’s HRPD (high rate packet data), UMB (ultra mobile broadband), and IEEE’s 802.17e communication standards.

[0050] In the LTE system, a representative example of a broadband wireless communication system, the downlink (DL) employs the orthogonal frequency division multiplexing (OFDM) method, and the uplink (UL) employs the single carrier frequency division multiple access (SC-FDMA) method. The uplink refers to a wireless link through which a terminal (hereinafter referred to as user equipment (UE) or terminal) (or mobile station (MS)) transmits data or control signals to a base station (eNode B (eNB) or base station (BS)), and the downlink refers to a wireless link through which a base station transmits data or control signals to a terminal (UE). Furthermore, the aforementioned multiple access method typically ensures that the time-frequency resources to be used to transmit data or control information for each user do not overlap, that is, that orthogonality is established, thereby allowing the data or control information of each user to be distinguished.

[0051] 5G communication systems, which are communication systems following LTE, must support services that simultaneously satisfy various requirements so as to freely reflect the diverse needs of users and service providers. Services considered for 5G communication systems include enhanced mobile broadband (eMBB), massive machine type communication (mMTC), or ultra reliability low latency communication (URLC).

[0052] eMBB aims to provide data transmission speeds that are superior to those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must be able to provide a peak data rate of 20 Gbps in the downlink and 10 Gbps in the uplink from the perspective of a single base station. Furthermore, while providing the peak data rates, the 5G communication system must also provide an increased user-perceived data rate. To satisfy these requirements, improvements in various transmission and reception technologies, including enhanced multi-input multi-output (MIMO) transmission technology, may be required. Additionally, while LTE systems transmit signals using a maximum transmission bandwidth of 20 MHz in the 2 GHz band, 5G communication systems can meet the data transmission speeds required by the 5G communication system by using a frequency bandwidth wider than 20 MHz in frequency bands of 3 to 6 GHz or above 6 GHz.

[0053] At the same time, mMTC is being considered to support application services such as the Internet of Things (IoT) in 5G communication systems. To efficiently provide IoT, mMTC requires support for the connection of a large number of terminals within a cell, improved terminal coverage, enhanced battery life, and reduced terminal costs. Since IoT provides communication functions by attaching various sensors and diverse devices, a large number of terminals (e.g., 1,000,000 terminals / km²) are required within a cell. 2 It must be able to support mMTC. In addition, terminals supporting mMTC require wider coverage compared to other services provided by the 5G communication system, as they are likely to be located in dead zones where cells cannot cover, such as building basements, due to the nature of the service. Terminals supporting mMTC must be low-cost devices, and because it is difficult to frequently replace the device's battery, they require a very long battery life of 10 to 16 years.

[0054] Finally, URLLC is a mission-critical cellular-based wireless communication service. For example, consider services used for remote control of robots or machinery, industrial automation, unmanned aerial vehicles, remote health care, or emergency alerts. Therefore, the communication provided by URLLC must offer very low latency and very high reliability. For example, services supporting URLLC must satisfy air interface latency of less than 0.5 milliseconds, and simultaneously 10 -5The following packet error rate requirements must be satisfied. Therefore, for services supporting URLLC, 5G systems must provide a transmit time interval (TTI) smaller than other services, and at the same time, allocate a wide resource in the frequency band to ensure the reliability of the communication link.

[0055] Three services of a 5G communication system (hereinafter interchangeable with 5G systems), namely eMBB, URLLC, and mMTC, can be multiplexed and transmitted within a single system. To satisfy the different requirements of each service, different transmission and reception techniques and transmission and reception parameters may be used between the services.

[0056] The frame structure of a 5G system will be described in more detail below with reference to the drawings. For convenience of explanation, the wireless communication system to which the present disclosure applies will be described below using the configuration of a 5G system as an example; however, the embodiments of the present disclosure may be applied in the same or similar manner to systems of 5G or higher or other communication systems to which the present disclosure is applicable.

[0057] FIG. 1 illustrates the basic structure of the time-frequency domain, which is a wireless resource domain in a wireless communication system according to one embodiment of the present disclosure.

[0058] In FIG. 1, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. In the time and frequency domains, the basic unit of a resource is a resource element (RE, 101), which can be defined as one Orthogonal Frequency Division Multiplexing (OFDM) symbol (or Discrete Fourier Transform Spread OFDM) symbol) (102) on the time axis and one subcarrier (103) on the frequency axis. In the frequency domain, the number of subcarriers per resource block (RB) is indicated. (For example, 12) consecutive REs can constitute a single resource block (RB, 104). Additionally, representing the number of symbols per subframe according to the set value μ for subcarrier spacing in the time domain. A number of consecutive OFDM symbols can form a subframe (110).

[0059] FIG. 2 illustrates a slot structure considered in a wireless communication system according to one embodiment of the present disclosure.

[0060] FIG. 2 illustrates an example of a slot structure comprising a frame (200), a subframe (201), and slots (202, 203). One frame (200) may be defined as 10 ms. One subframe (201) may be defined as 1 ms, and thus one frame (200) may consist of a total of 10 subframes (201). One slot (202, 203) may be defined as 14 OFDM symbols (i.e., the number of symbols per slot ( ))=14). One subframe (201) may be composed of one or more slots (202, 203), and the number of slots (202, 203) per one subframe (201) may vary depending on μ (204 or 205), which is a setting value for the subcarrier space (SCS).

[0061] The slot structure for cases where the subcarrier spacing setting value is μ=0 (204) and μ=1 (205) is illustrated. When μ=0 (204), one subframe (201) may be composed of one slot (202), and when μ=1 (205), one subframe (201) may be composed of two slots (e.g., including slot (203)). That is, depending on the setting value μ for the subcarrier spacing, the number of slots per subframe ( )) may vary, and accordingly, the number of slots per frame ( ) may vary. For example, depending on the setting μ for each subcarrier interval. and It can be defined by the following [Table 1].

[0062] 014101114202214404314808414160165143203261464064

[0063] In a 5G wireless communication system, a synchronization signal block (SSB, which may be used interchangeably with SS block or SS / PBCH block) may be transmitted for the initial connection of a terminal, and the synchronization signal block may include a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a physical broadcast channel (PBCH). In the initial access phase where the terminal connects to the system, the terminal can first obtain downlink time and frequency domain synchronization from the synchronization signal through a cell search and obtain a cell ID. The synchronization signal may include the PSS and SSS. Furthermore, the terminal can receive a PBCH transmitting a master information block (MIB) from the base station to obtain system information related to transmission and reception, such as system bandwidth or related control information, as well as basic parameter values. Based on this information, the terminal can use the physical downlink control channel (PDCCH) and the physical downlink shared channel (PDSCH). The System Information Block (SIB) can be obtained by performing decoding on the Channel. Subsequently, the terminal can exchange identification information with the base station through a random access step and establish an initial connection to the network after going through registration and authentication steps. Additionally, the terminal can obtain cell-common transmission and reception control information by receiving the System Information Block (SIB) transmitted by the base station.The above cell-common transmission and reception control information may include random access-related control information, paging-related control information, and common control information for various physical channels. The synchronization signal is a signal serving as a reference for cell search, and a subcarrier spacing may be applied for each frequency band to suit channel environments such as phase noise. In the case of data channels or control channels, as described above, a different subcarrier spacing may be applied depending on the service type to support various services.

[0064] FIG. 3 illustrates an example of a time domain mapping structure of a synchronization signal and a beam sweeping operation according to one embodiment of the present disclosure.

[0065] For the purpose of explanation, the following components may be defined.

[0066] - PSS (Primary Synchronization Signal): A signal that serves as the reference for DL ​​time / frequency synchronization and provides some cell ID information.

[0067] - SSS (Secondary Synchronization Signal): Serves as a reference for DL ​​time / frequency synchronization and provides some of the remaining information, including the cell ID. Additionally, it can serve as a reference signal for PBCH demodulation.

[0068] - PBCH (Physical Broadcast Channel): Provides the Master Information Block (MIB), which is essential system information required for the transmission and reception of the terminal's data and control channels. The said essential system information may include control information related to the search space representing wireless resource mapping information of the control channel, scheduling control information for a separate data channel transmitting system information, and information such as the System Frame Number (SFN), which is a frame-unit index serving as a timing reference.

[0069] - SS / PBCH Block (Synchronization Signal / PBCH Block or SSB): An SS / PBCH block consists of N OFDM symbols and is formed by a combination of PSS, SSS, PBCH, etc. In systems where beam sweeping technology is applied, the SS / PBCH block is the minimum unit to which beam sweeping is applied. In a 5G system, N can be 4. A base station can transmit up to L SS / PBCH blocks, and the L SS / PBCH blocks are mapped within a half frame (0.5ms). The L SS / PBCH blocks are repeated periodically in units of a predetermined period P. The base station can notify the terminal of the period P through signaling. If there is no separate signaling for the period P, the terminal applies a pre-agreed default value.

[0070] Referring to FIG. 3, beam sweeping can be applied in units of SS / PBCH blocks over time. In the case of Terminal 1 (305), at time t1 (301), it receives an SS / PBCH block using a beam radiated in the direction of #d0 (303) by beamforming applied to SS / PBCH block #0. Then, at time t2 (302), Terminal 2 (306) receives an SS / PBCH block using a beam radiated in the direction of #d4 (304) by beamforming applied to SS / PBCH block #4. The terminal can obtain an optimal synchronization signal through a beam radiated from the base station in the direction where the terminal is located. For example, it may be difficult for Terminal 1 (305) to obtain time / frequency synchronization and essential system information from an SS / PBCH block through a beam radiated in the direction of #d4 (304), which is far from the location of Terminal 1 (305).

[0071] In addition to the initial connection procedure, the terminal may also receive SS / PBCH blocks to determine whether the radio link quality of the current cell is maintained above a certain level. Furthermore, during the handover procedure in which the terminal moves the connection from the current cell to an adjacent cell, the terminal may receive SS / PBCH blocks of the adjacent cell to determine the radio link quality of the adjacent cell and to obtain time / frequency synchronization with the adjacent cell.

[0072] Below, the cell initial connection operation procedure of a 5G wireless communication system will be explained in more detail with reference to the drawings.

[0073] Synchronization signals serve as reference signals for cell search and can be transmitted with subcarrier spacing applied to suit the channel environment (e.g., phase noise) for each frequency band. 5G base stations can transmit multiple synchronization signal blocks depending on the number of analog beams to be operated. For example, PSS and SSS can be mapped and transmitted across 12 RBs, while PBCH can be mapped and transmitted across 24 RBs. The structure of synchronization signal and PBCH transmission in a 5G communication system is described below.

[0074] FIG. 4 illustrates a synchronization signal block considered in a wireless communication system according to one embodiment of the present disclosure.

[0075] Referring to FIG. 4, the synchronization signal block (SS block, SSB) (400) may include PSS (401), SSS (403), and PBCH (Physical Broadcast Channel) (402).

[0076] The synchronization signal block (400) can be mapped to four OFDM symbols (404) in the time axis. The PSS (401) and SSS (403) can be transmitted at 12 RB (405) in the frequency axis and at the first and third OFDM symbols in the time axis, respectively. In a 5G system, for example, a total of 1008 different cell IDs can be defined. Depending on the physical cell ID (PCI) of the cell, the PSS (401) can have three different values, and the SSS (403) can have 336 different values. The terminal can obtain one of the 1008 cell IDs (336 x 3 = 1008) as a combination through detection of the PSS (401) and SSS (403). This can be expressed by the following [Equation 1].

[0077]

[0078] Here can be estimated from SSS(403) and can have a value between 0 and 335. can be estimated from PSS (401) and can have a value between 0 and 2. The terminal class The cell ID is a combination of The value can be estimated.

[0079] PBCH (402) can be transmitted from a resource containing 6 RBs (407, 408) on each side excluding 12 RBs (405), with 24 RBs (406) in the frequency axis and SSS (403) in the 2nd to 4th OFDM symbols of the SS block in the time axis being transmitted. PBCH (402) may include a PBCH payload and a PBCH DMRS (demodulation reference signal), and various system information called MIB may be transmitted in the PBCH payload. For example, the MIB may include information such as that shown in [Table 2] below.

[0080] [Table 2]

[0081]

[0082] - Synchronization signal block information: The frequency domain offset of the synchronization signal block can be indicated through the 4-bit ssb-SubcarrierOffset within the MIB. The index of the synchronization signal block containing the PBCH can be obtained indirectly through PBCH DMRS and decoding of the PBCH. In one embodiment, in a frequency band below 6 GHz, 3 bits obtained through decoding of the PBCH DMRS indicate the synchronization signal block index, and in a frequency band above 6 GHz, a total of 6 bits, including 3 bits obtained through decoding of the PBCH DMRS and 3 bits included in the PBCH payload obtained from PBCH decoding, can indicate the synchronization signal block index containing the PBCH.

[0083] - PDCCH (physical downlink control channel) configuration information: The subcarrier spacing of the common downlink control channel can be indicated via a 1-bit (subCarrierSpacingCommon) within the MIB, and the time-frequency resource configuration information of the CORESET (control resource set) and search space (SS) of Identifier (ID) 0 can be indicated via an 8-bit (pdcch-ConfigSIB1). The CORESET of Identifier 0 can be referred to as controlResourceSetZero, and the search space of Identifier 0 can be referred to as searchspaceZero. In this disclosure, for convenience, the CORESET of Identifier 0 will be referred to as CORESET#0 or control space#0, and the search space of Identifier 0 will be referred to as search space#0. During the initial connection of the cell, the terminal can receive frequency resources indicating the number of RBs of CORESET#0, which includes the common search space set of Type0-PDCCH CSS set, and time resources indicating the number of OFDM symbols, etc., from the pdcch-ConfigSIB1.

[0084] - SFN (system frame number): Within the MIB, 6 bits (systemFrameNumber) can be used to indicate part of the SFN. The 4 bits of the SFN's LSB (Least Significant Bit) are included in the PBCH payload, and the terminal can obtain them indirectly through PBCH decoding.

[0085] - Timing information within a radio frame: With the synchronization signal block index described above and the 1-bit (half frame) obtained through PBCH decoding included in the PBCH payload, the terminal can indirectly check whether the synchronization signal block was transmitted in the first or second half frame of the radio frame.

[0086] Since the transmission bandwidth (12 RB (405)) of PSS (401) and SSS (403) and the transmission bandwidth (24 RB (406)) of PBCH (402) are different, in the first OFDM symbol where PSS (401) is transmitted within the transmission bandwidth of PBCH (402), there are 6 RBs (407, 408) on both sides excluding the 12 RB in the middle where PSS (401) is transmitted, and the area may be used to transmit other signals or be empty.

[0087] - Cell connection permission information: A 1-bit (cellBarred) within the MIB may indicate whether camping to a cell is permitted. Additionally, if camping to the cell with the best reception quality is prohibited (barred), a 1-bit (intraFreqReselection) within the MIB may indicate whether cell reselection to an intra-frequency cell is permitted.

[0088] Synchronization signal blocks can be transmitted using the same analog beam. For example, PSS (401), SSS (403), and PBCH (402) can all be transmitted on the same beam. Since analog beams have the characteristic that they cannot be applied differently in the frequency axis, the same analog beam can be applied to all frequency axis RBs within a specific OFDM symbol to which a specific analog beam is applied. For example, four OFDM symbols in which PSS (401), SSS (403), and PBCH (402) are transmitted can all be transmitted on the same analog beam.

[0089] FIG. 5 illustrates various transmission cases of a synchronization signal block in a frequency band below 6 GHz considered in a wireless communication system according to one embodiment of the present disclosure.

[0090] Referring to FIG. 5, in a 5G communication system, in a frequency band of 6 GHz or lower (or FR1 (frequency range 1), e.g., 410 MHz-7125 MHz), a subcarrier spacing (SCS) of 15 kHz (520) and a subcarrier spacing (SCS) of 30 kHz (530, 540) may be used for the transmission of a synchronization signal block. In the 15 kHz subcarrier spacing (520), there is one transmission case for the synchronization signal block (e.g., Case #1 (501)), and in the 30 kHz subcarrier spacing (530, 540), there may be two transmission cases for the synchronization signal block (e.g., Case #2 (502) and Case #3 (503)).

[0091] In case #1 (501) at a subcarrier interval of 15 kHz (520) in FIG. 5, up to two synchronization signal blocks can be transmitted within a time of 1 ms (504) (or corresponding to the length of one slot if one slot consists of 14 OFDM symbols). In an example of FIG. 5, synchronization signal block #0 (507) and synchronization signal block #1 (508) are shown. For example, synchronization signal block #0 (507) can be mapped to four consecutive symbols starting from the 3rd OFDM symbol, and synchronization signal block #1 (508) can be mapped to four consecutive symbols starting from the 9th OFDM symbol.

[0092] Different analog beams may be applied to synchronization signal block #0 (507) and synchronization signal block #1 (508). Also, the same beam may be applied to all 3rd to 6th OFDM symbols mapped to synchronization signal block #0 (507), and the same beam may be applied to all 9th ​​to 12th OFDM symbols mapped to synchronization signal block #1 (508). For the 7th, 8th, 13th, and 14th OFDM symbols that are not mapped to synchronization signal blocks, the analog beam to be used may be freely determined at the discretion of the base station.

[0093] In case #2 (502) at a subcarrier interval of 30 kHz (530) in FIG. 5, up to two synchronization signal blocks can be transmitted within a time of 0.5 ms (505) (or corresponding to the length of one slot if one slot consists of 14 OFDM symbols), and accordingly, up to four synchronization signal blocks can be transmitted within a time of 1 ms (or corresponding to the length of two slots if one slot consists of 14 OFDM symbols). In one example of FIG. 5, a case is illustrated in which synchronization signal block #0 (509), synchronization signal block #1 (510), synchronization signal block #2 (511), and synchronization signal block #3 (512) are transmitted within a time of 1 ms (i.e., two slots). Synchronization signal block #0 (509) and synchronization signal block #1 (510) can be mapped starting from the 5th OFDM symbol and 9th OFDM symbol of the first slot, respectively, and synchronization signal block #2 (511) and synchronization signal block #3 (512) can be mapped starting from the 3rd OFDM symbol and 7th OFDM symbol of the second slot, respectively.

[0094] Different analog beams may be applied to each of the synchronization signal block #0 (509), synchronization signal block #1 (510), synchronization signal block #2 (511), and synchronization signal block #3 (512). Additionally, the same analog beam may be applied to each of the 5th to 8th OFDM symbols in the first slot where synchronization signal block #0 (509) is transmitted, the 9th to 12th OFDM symbols in the first slot where synchronization signal block #1 (510) is transmitted, the 3rd to 6th symbols in the second slot where synchronization signal block #2 (511) is transmitted, and the 7th to 10th symbols in the second slot where synchronization signal block #3 (512) is transmitted. For OFDM symbols where the synchronization signal block is not mapped, the analog beam to be used may be freely determined at the discretion of the base station.

[0095] In case #3 (503) at a subcarrier interval of 30 kHz (540) in FIG. 5, up to two synchronization signal blocks can be transmitted within a time of 0.5 ms (506) (or corresponding to the length of one slot if one slot consists of 14 OFDM symbols), and accordingly, up to four synchronization signal blocks can be transmitted within a time of 1 ms (or corresponding to the length of two slots if one slot consists of 14 OFDM symbols). In one example of FIG. 5, synchronization signal block #0 (513), synchronization signal block #1 (514), synchronization signal block #2 (515), and synchronization signal block #3 (516) are shown being transmitted within a time of 1 ms (i.e., two slots). Synchronization signal block #0 (513) and synchronization signal block #1 (514) can be mapped starting from the 3rd OFDM symbol and 9th OFDM symbol of the first slot, respectively, and synchronization signal block #2 (515) and synchronization signal block #3 (516) can be mapped starting from the 3rd OFDM symbol and 9th OFDM symbol of the second slot, respectively.

[0096] Different analog beams may be used for each of the synchronization signal block #0 (513), synchronization signal block #1 (514), synchronization signal block #2 (515), and synchronization signal block #3 (516). As described in the examples above, the same analog beam may be used for all four OFDM symbols in which each synchronization signal block is transmitted, and for OFDM symbols in which the synchronization signal block is not mapped, the choice of which beam to use may be freely determined by the base station.

[0097] FIG. 6 illustrates transmission cases of a synchronization signal block in a frequency band of 6 GHz or higher considered in a wireless communication system according to one embodiment of the present disclosure.

[0098] Referring to FIG. 6, in a wireless communication system, in a frequency band of 6 GHz or higher (or FR2, e.g., 24250 MHz-52000 MHz), a subcarrier spacing of 120 kHz (630), as in the example of Case #4 (610), and a subcarrier spacing of 240 kHz (640), as in the example of Case #5 (620), can be used for the transmission of synchronization signal blocks.

[0099] In case #4 (610) of a subcarrier interval of 120 kHz (630), up to four synchronization signal blocks can be transmitted within a time of 0.25 ms (601) (or, if one slot consists of 14 OFDM symbols, the length of two slots). In an example of FIG. 6, a case is illustrated in which synchronization signal block #0 (603), synchronization signal block #1 (604), synchronization signal block #2 (605), and synchronization signal block #3 (606) are transmitted within 0.25 ms (i.e., two slots). Synchronization signal block #0 (603) and synchronization signal block #1 (604) can each be mapped to four consecutive symbols starting from the 5th OFDM symbol of the first slot and to four consecutive symbols starting from the 9th OFDM symbol, and synchronization signal block #2 (605) and synchronization signal block #3 (606) can each be mapped to four consecutive symbols starting from the 3rd OFDM symbol of the second slot and to four consecutive symbols starting from the 7th OFDM symbol.

[0100] As described in the above embodiment, different analog beams may be used for each of the synchronization signal block #0 (603), synchronization signal block #1 (604), synchronization signal block #2 (605), and synchronization signal block #3 (606). In addition, the same analog beam may be used for all four OFDM symbols transmitted by each synchronization signal block, and for OFDM symbols that are not mapped to the synchronization signal block, the choice of which beam to use may be freely determined by the base station.

[0101] In case #5 (620) at a subcarrier interval of 240 kHz (640), up to 8 synchronization signal blocks can be transmitted within a time of 0.25 ms (602) (or corresponding to a length of 4 slots if 1 slot consists of 14 OFDM symbols). In an example of FIG. 6, a case is illustrated in which synchronization signal block #0 (607), synchronization signal block #1 (608), synchronization signal block #2 (609), synchronization signal block #3 (610), synchronization signal block #4 (611), synchronization signal block #5 (612), synchronization signal block #6 (613), and synchronization signal block #7 (614) are transmitted within 0.25 ms (i.e., 4 slots).

[0102] Synchronization signal block #0 (607) and synchronization signal block #1 (608) can each be mapped to four consecutive symbols starting from the 9th OFDM symbol of the first slot and to four consecutive symbols starting from the 13th OFDM symbol, and synchronization signal block #2 (609) and synchronization signal block #3 (610) can each be mapped to four consecutive symbols starting from the 3rd OFDM symbol of the second slot and to four consecutive symbols starting from the 7th OFDM symbol, and synchronization signal block #4 (611), synchronization signal block #5 (612), and synchronization signal block #6 (613) can each be mapped to four consecutive symbols starting from the 5th OFDM symbol of the third slot, to four consecutive symbols starting from the 9th OFDM symbol and to four consecutive symbols starting from the 13th OFDM symbol, and synchronization signal block #7 (614) can be mapped to the 3rd OFDM symbol of the fourth slot It can be mapped to four consecutive symbols starting from the symbol.

[0103] As described in the above embodiment, different analog beams may be used for each of the synchronization signal block #0 (607), synchronization signal block #1 (608), synchronization signal block #2 (609), synchronization signal block #3 (610), synchronization signal block #4 (611), synchronization signal block #5 (612), synchronization signal block #6 (613), and synchronization signal block #7 (614). In addition, the same analog beam may be used for all four OFDM symbols transmitted by each synchronization signal block, and for OFDM symbols that are not mapped to the synchronization signal block, the choice of which beam to use may be freely determined by the base station.

[0104] FIG. 7 illustrates transmission cases of a synchronization signal block according to a subcarrier interval within 5ms in a wireless communication system according to one embodiment of the present disclosure.

[0105] Referring to FIG. 7, in a 5G communication system, a synchronization signal block can be transmitted periodically in units of, for example, a time interval (710) of 5 ms (corresponding to 5 subframes or half frames).

[0106] In the frequency band below 3 GHz, up to 4 synchronization signal blocks can be transmitted within a time of 5 ms (710). In the frequency band between 3 GHz and 6 GHz, up to 8 synchronization signal blocks can be transmitted. In the frequency band above 6 GHz, up to 64 synchronization signal blocks can be transmitted. As described above, subcarrier spacings of 15 kHz and 30 kHz can be used in frequencies below 6 GHz.

[0107] In the example of FIG. 7, in case #1 (501) with a subcarrier interval of 15 kHz consisting of one slot of FIG. 5, a synchronization signal block can be mapped to the first and second slots in the frequency band below 3 GHz, allowing up to 4 (721) to be transmitted, and in the frequency band above 3 GHz and below 6 GHz, a synchronization signal block can be mapped to the first, second, third, and fourth slots, allowing up to 8 (722) to be transmitted. In case #2 (502) or case #3 (503) with a subcarrier interval of 30 kHz consisting of two slots of FIG. 5, a synchronization signal block can be mapped starting from the first slot in the frequency band below 3 GHz, allowing up to 4 (731, 741) to be transmitted, and in the frequency band above 3 GHz and below 6 GHz, a synchronization signal block can be mapped starting from the first and third slots, allowing up to 8 (732, 742) to be transmitted.

[0108] Subcarrier spacing of 120 kHz and 240 kHz can be used at frequencies above 6 GHz. In the example of FIG. 7, in case #4 (610) at a subcarrier spacing of 120 kHz consisting of two slots of FIG. 6, synchronization signal blocks in the frequency band above 6 GHz can be mapped starting from the 1st, 3rd, 5th, 7th, 11th, 13th, 15th, 17th, 21st, 23rd, 25th, 27th, 31st, 33rd, 35th, and 37th slots, so that up to 64 (751) can be transmitted. In the example of FIG. 7, in case #5 (620) at a subcarrier interval of 240 kHz consisting of 4 slots of FIG. 6, synchronization signal blocks in the over 6 GHz frequency band can be mapped starting from the 1st, 5th, 9th, 13th, 21st, 25th, 29th, and 33rd slots, so that up to 64 (761) can be transmitted.

[0109] Next, we will explain in detail the Bandwidth Part (BWP) settings in the 5G communication system.

[0110] In a 5G communication system, the base station can set one or more bandwidth portions for the terminal, and for each bandwidth portion, it can set the information included in [Table 3] below.

[0111] BWP ::= SEQUENCE {bwp-Id BWP-Id,(Bandwidth Identifier)locationAndBandwidth INTEGER (1..65536),(Bandwidth Location)subcarrierSpacing ENUMERATED {n0, n1, n2, n3, n4, n5},(Subcarrier Spacing)cyclicPrefix ENUMERATED { extended}(Cyclical Prefix)}

[0112] In addition to the above configuration information, various parameters related to bandwidth portions may be configured for the terminal. These information may be transmitted by the base station to the terminal via upper-layer signaling, such as RRC signaling. Among the one or more configured bandwidth portions, at least one bandwidth portion may be activated. Whether a configured bandwidth portion is activated may be transmitted quasi-statically from the base station to the terminal via RRC signaling or dynamically via DCI (downlink control information).

[0113] Before RRC connection, the terminal can receive an Initial Bandwidth Part (Initial BWP) for initial connection from the base station via the Master Information Block (MIB) or System Information Block 1 (SIB1).

[0114] To explain specifically regarding the configuration of Control Area #0, Search Area #0, and the initial bandwidth portion, the terminal can receive configuration information for Control Area #0 and Search Area #0 through the MIB during the initial connection phase, through which a PDCCH can be transmitted to receive system information required for initial connection (Remaining System Information; which may correspond to RMSI or System Information Block 1; SIB1). The Control Area and Search Area configured by the MIB can each be considered as Identifier (ID) 0. The base station can notify the terminal of configuration information, such as frequency allocation information, time allocation information, and numerology, for Control Area #0 through the MIB. Additionally, the base station can notify the terminal of configuration information regarding the monitoring period and occasion for Control Area #0, that is, configuration information for Search Area #0, through the MIB.

[0115] In the method for setting the initial bandwidth part described above, terminals prior to RRC connection (Connected) can receive configuration information for the initial bandwidth part through the Master Information Block (MIB) during the initial connection phase. More specifically, the terminal can receive a Control Resource Set (CORESET) for a downlink control channel through which Downlink Control Information (DCI) scheduling System Information Blocks (SIB) can be transmitted from the MIB of the Physical Broadcast Channel (PBCH). The bandwidth of the control resource set by the MIB can be considered as the initial bandwidth part, and through the configured initial bandwidth part, the terminal can receive the PDSCH through which the SIB is transmitted. In addition to receiving the SIB, the initial bandwidth part may also be utilized for other system information (OSI), paging, and random access.

[0116] The terminal can obtain SIB1 or SIBx (all SIBs excluding SIB1) after performing decoding of PDCCH and PDSCH based on system information contained in the received MIB. SIB1 may include at least one of uplink cell bandwidth-related information, random access parameters, paging parameters, or parameters related to uplink power control.

[0117] Generally, a terminal can establish a wireless link with a network through a random access procedure based on network synchronization and system information acquired during the cell's cell search process. Random access may utilize contention-based or contention-free methods. When a terminal performs cell selection and re-selection during the initial connection phase of a cell, a contention-based random access method may be used, for example, to transition from the RRC_IDLE state to the RRC_CONNECTED state. Contention-free random access may be used to reset uplink synchronization when downlink data arrives, in the case of a handover, or for location measurement. Table 4 below illustrates the conditions (events) under which the random access procedure is triggered in a 5G system.

[0118] - Initial access from RRC_IDLE;- RRC Connection Re-establishment procedure;- DL or UL data arrival during RRC_CONNECTED when UL synchronisation status is "non-synchronised";- UL data arrival during RRC_CONNECTED when there are no PUCCH resources for SR available;- SR failure;- Request by RRC upon synchronous reconfiguration (e.g. handover);- RRC Connection Resume procedure from RRC_INACTIVE;- To establish time alignment for a secondary TAG;- Request for Other SI;- Beam failure recovery;- Consistent UL LBT failure on SpCell.

[0119] When a terminal successfully completes the random access procedure, the terminal transitions to a connected state (or RRC_CONNECTED state), enabling one-to-one communication between the base station and the terminal. The base station receives UE capability information from the terminal in the connected state (or RRC_CONNECTED state) and can adjust scheduling by referring to the terminal's UE capability information. Through the UE capability information, the terminal can inform the base station whether it supports a specific function, the maximum allowable value of the function supported by the terminal, etc. Therefore, the UE capability information reported by each terminal to the base station may be different for each terminal. For example, a terminal may report UE capability information to the base station that includes at least one of the following control information.

[0120] - Control information related to frequency bands supported by the terminal

[0121] - Control information related to channel bandwidth supported by the terminal

[0122] - Control information regarding the maximum modulation scheme supported by the terminal

[0123] - Control information regarding the maximum number of beams supported by the terminal

[0124] - Control information regarding the maximum number of layers supported by the terminal

[0125] - Control information related to CSI reporting supported by the terminal

[0126] - Control information on whether the terminal supports frequency hopping

[0127] - Bandwidth-related control information when Carrier Aggregation (CA) is supported

[0128] - Control information on whether cross-carrier scheduling is supported when carrier bundling is supported

[0129] Based on the transmission and reception process of terminal capability information, a terminal connected to a base station can communicate one-to-one with the base station as a terminal in the RRC_CONNECTED state. A terminal in the RRC_CONNECTED state can perform the following operations.

[0130] - Monitoring of the Physical Downlink Control Channel (PDCCH)

[0131] - Radio Link Monitoring

[0132] - Beam failure detection and beam failure recovery

[0133] First, the monitoring of the downlink control channel of a terminal in the RRC_CONNECTED state is described in detail. If Discontinuous Reception (DRX) is not established from the base station, the terminal's Medium Access Control (MAC) entity can continuously monitor the PDCCH. If DRX is established to the terminal's MAC entity by an upline signal from the base station, the terminal's MAC entity can monitor the PDCCH discontinuously using the DRX operation for all activated serving cells. The terminal receives DRX operation-related parameters (e.g., including at least one of DRX cycle, drx-onDurationTimer, drx-InactivityTimer, or drx-SlotOffset) by an upline signal from the base station and can discontinuously monitor the PDCCH based on said parameters. In the present disclosure, monitoring the PDCCH with DRX by the RRC_CONNECTED terminal above may be described as performing a C-DRX (CONNECTED-DRX) operation or performing C-DRX.

[0134] Next, radio link monitoring by a terminal in the RRC_CONNECTED state is described in detail. The terminal performs radio link monitoring for a serving cell (or a primary serving cell (primary cell), i.e., a P-cell) using CSI-RS (channel state information-reference signal) or SS / PBCH signals. Performing radio link monitoring can be explained as measuring the quality of the radio link using the aforementioned signals to determine whether the radio link is in-sync or out-of-sync. Which signal, CSI-RS or SS / PBCH, is used for radio link monitoring can be configured by receiving a higher-level signal from the base station.

[0135] When measuring the quality of the above radio link, the evaluation period for measuring and evaluating whether it is in-sync or out-of-sync is described. The in-sync evaluation period and the out-of-sync evaluation period may be determined differently depending on whether a DRX is configured for PDCCH monitoring from the base station, and if a DRX is configured, the DRX period value. Next, the indication period is described, during which the terminal's physical layer sends the evaluated in-sync or out-of-sync status to the terminal's upper layer as a result of the measurement and evaluation. If a DRX is not configured, the indication period is determined as the maximum value between the shortest period of the resource for radio link monitoring and Xms. X can be 2 or 10. Conversely, if a DRX is configured, the indication period is determined as the maximum value between the shortest period of the resource for radio link monitoring and the DRX period.

[0136] The above in-sync is explained. When the radio link quality is better than the threshold Q_in received from the base station configuration for any resources in the resource set for radio link monitoring, the physical layer of the terminal transmits an in-sync to the upper layer of the terminal in the frame where the radio link quality is evaluated. To determine the in-sync of the radio link quality, the terminal determines whether the block error rate (BLER) when performing PDCCH decoding from hypothetical downlink control channel (hypothetical PDCCH) parameters is smaller than a predefined value. The predefined value may be, for example, 2%. The above downlink control channel parameters may be determined differently depending on which signal is used to perform radio link monitoring.

[0137] The above out-of-sync is explained. If, for any resources in the resource set for radio link monitoring, the radio link quality is worse than the threshold Q_out received from the base station configuration, the physical layer of the terminal transmits out-of-sync to the upper layer of the terminal in the frame where the radio link quality is evaluated. To determine the out-of-sync of the radio link quality, the terminal determines whether the block error rate when performing PDCCH decoding from virtual downlink control channel parameters is greater than a predefined value. The predefined value may be, for example, 10%. The above downlink control channel parameters may be determined differently depending on which signal is used to perform radio link monitoring.

[0138] The terminal's upper layer (or the terminal) initiates the T310 timer after receiving N310 consecutive out-of-sink signals. If the terminal receives N311 consecutive in-sink signals, the T310 timer is stopped. Otherwise, the terminal declares a Radio Link Failure (RLF) and initiates the T311 timer. The terminal performs cell selection to find a suitable cell. If no suitable cell is found and the T311 timer expires, the terminal transitions to the RRC_IDLE state. If a suitable cell is found, the T311 timer is stopped, the terminal transmits an RRC Reestablishment Request message to the base station of the cell, and initiates the T301 timer. If the RRC Reestablishment operation is not successfully completed and the T301 timer expires, the terminal transitions to the RRC_IDLE state. If the RRC Reestablishment operation is successfully completed within the T301 timer, the terminal transitions to the normal RRC_CONNECTED state.

[0139] Parameters and timers for performing procedures related to radio link monitoring and radio link failure, such as the above N310, T310 timer, N311, T311 timer, T301 timer, etc., can be set to the terminal by a higher signal from the base station.

[0140] Next, Beam Failure Detection (BFD) and Beam Failure Recovery (BFR) for a terminal in the RRC_CONNECTED state are explained in detail. The terminal performs beam failure detection for the serving cell using CSI-RS or SS / PBCH signals. Performing beam failure detection can be explained as measuring the quality of the beam using the aforementioned signals to determine whether the reception status of the beam is reliable (for example, whether the virtual downlink control channel block error rate for the measured beam quality is smaller than a predefined value).

[0141] If the reception status of the beam is unreliable, that is, if the virtual downlink control channel block error rate for the measured beam quality is equal to or greater than the predefined value, it is defined as a beam failure instance. Whether to use the CSI-RS or SS / PBCH signal to perform beam failure detection can be configured by receiving an upper signal from the base station. To determine the virtual downlink control channel block error rate, the terminal determines whether the block error rate when performing PDCCH decoding from virtual downlink control channel parameters (e.g., a specific DCI format, the number of OFDM symbols of the PDCCH, the PDCCH aggregation level, the PDCCH bandwidth, subcarrier spacing, the REG (resource element group) bundle size, the CP (cyclic prefix) length, etc.) is greater than the predefined value. The predefined value may be, for example, 10%. The downlink control channel parameters may be determined differently depending on which signal is used to perform beam failure detection.

[0142] When the above beam failure instance increases by 1, the timer (beamFailureDetectionTimer) associated with the beam failure instance is restarted, and if the terminal (or the terminal's MAC layer) fails to detect additional beam failure instances until the timer expires, the accumulated beam failure instance (BFI_COUNTER) is reset.

[0143] If the accumulated number of beam failure instances is equal to or greater than the maximum number of beam failure instances (beamFailureInstanceMaxCount) set by the base station as an upper signal, the terminal (or the terminal's MAC layer) may trigger beam failure recovery. When beam failure recovery is triggered, the terminal (or the terminal's MAC layer) may perform beam failure recovery by performing random access to the base station using the resources or random access preamble set on the best candidate beam. For beam failure recovery, the terminal may perform contention-free random access (contention-free random access) (CFRA) using the downlink control channel resources (control resource set, CORESET) set by the base station and the random access preamble. If the above collision-free random access fails, or if there is no best candidate beam allocated to the above collision-free random access, or if a collision-free random access resource or random access preamble is not set, the terminal can perform beam failure recovery by performing a collision-free random access (contention-based random access, CBRA).

[0144] Next, unlike the RRC_CONNECTED state, a terminal that is not connected to the base station may be in the RRC_IDLE state, and a terminal in the RRC_IDLE state can perform the following process.

[0145] - Performing a terminal-specific DRX (Discontinuous Reception) cycle set by the upper layer, and the fact that a terminal in the RRC_IDLE state performs a DRX cycle can be described as performing an I-DRX (IDLE-DRX) operation or performing I-DRX.

[0146] - Receive paging messages from the core network

[0147] - Obtain system information

[0148] - Measurement actions related to the serving cell (or the cell currently being camped) and cell selection / reselection

[0149] - Measurement operation and cell reselection related to surrounding cells

[0150] - Receive PEI (Paging Early Indication)

[0151] The following describes a method for setting measurement times for Radio Resource Management (RRM) based on synchronization signal blocks (SS blocks or SSB) of 5G wireless communication systems.

[0152] The terminal receives the MeasObjectNR of MeasObjectToAddModList as a setting for SSB-based intra / inter-frequency measurements and CSI-RS (channel state information-reference signal)-based intra / inter-frequency measurements through upper layer signaling. For example, MeasObjectNR can be configured as shown in [Table 4-1] below.

[0153] [Table 4-1]

[0154]

[0155] The terms in [Table 4-1] can perform the following functions, but are not limited thereto.

[0156] - ssbFrequency: Allows you to set the frequency of the synchronization signal associated with MeasObjectNR.

[0157] - ssbSubcarrierSpacing: Sets the subcarrier spacing of the SSB. FR1 can only be applied at 15 kHz or 30 kHz, and FR2 at 120 kHz or 240 kHz.

[0158] - smtc1: Represents the SS / PBCH block measurement timing configuration. It allows you to set the primary measurement timing configuration and configure the timing offset and duration for the SSB.

[0159] - smtc2: Allows setting secondary measurement timing configuration for SSBs associated with MeasObjectNRs having PCIs listed in pci-List.

[0160] In addition to this, it can be configured through other higher-level signaling, for example, SMTC can be configured to the terminal through SIB2 for intra-frequency, inter-frequency, and inter-RAT cell re-selection, or through reconfigurationWithSync for NR PSCell change and NR PCell change, and SMTC can also be configured to the terminal through SCellConfig for NR SCell addition.

[0161] The terminal can set the first SS / PBCH block measurement timing configuration (SMTC) according to periodicityAndOffset (providing Periodicity and Offset) through smtc1 configured via upper layer signaling for SSB measurement. In one embodiment, the first subframe of each SMTC occasion can be started in a subframe of SpCell with a system frame number (SFN) satisfying the conditions of [Table 5] below.

[0162] SFN mod T = (FLOOR (Offset / 10));if the Periodicity is larger than sf5:subframe = Offset mod 10;else:subframe = Offset or (Offset +5);with T = CEIL(Periodicity / 10).

[0163] If smtc2 is configured, for the cells indicated by the pci-List value of smtc2 within the same MeasObjectNR, the terminal may configure additional SMTCs according to the periodicity of the configured smtc2 and the offset and duration of smtc1. In addition, the terminal may configure smtc and measure SSBs through smtc3list for smtc2-LP (with long periodicity) and IAB-MT (integrated access and backhaul - mobile termination) for the same frequency (e.g., frequencies for intra-frequency cell reselection) or different frequencies (e.g., frequencies for inter-frequency cell reselection). In one embodiment, the terminal may not consider SSBs transmitted in subframes other than the SMTC occasion for SSB-based RRM measurement at the configured ssbFrequency. The base station may use various multiple TRP (transmit / receive point or transmission / reception point) operation modes depending on the serving cell configuration and physical cell identifier (PCI) configuration. Among them, when two TRPs located at a physically separated distance have different PCIs, there are two ways to operate the two TRPs.

[0164] [Operation Method 1]

[0165] Two TRPs with different PCIs can be operated in a 2-serving cell configuration.

[0166] The base station can configure channels and signals transmitted from different TRPs to be included within different serving cell configurations through [Operation Method 1]. That is, each TRP has an independent serving cell configuration, and the frequency band values ​​FrequencyInfoDL indicated by DownlinkConfigCommon within each serving cell configuration may indicate at least some overlapping bands. Since the above multiple TRPs operate based on multiple ServCellIndexes (e.g., ServCellIndex #1 and ServCellIndex #2), it is possible for each TRP to use a separate PCI. That is, the base station can allocate one PCI per ServCellIndex.

[0167] In this case, if multiple SSBs are transmitted from TRP 1 and TRP 2, the SSBs have different PCIs (e.g., PCI #1 and PCI #2), and the base station can map the PCI corresponding to each TRP by appropriately selecting the value of ServCellIndex indicated by the cell parameter in QCL-Info, and designate the SSB transmitted from either TRP 1 or TRP 2 as the source reference RS of the QCL configuration information. However, since this configuration applies a single serving cell configuration that can be used for the terminal's carrier aggregation (CA) to multiple TRPs, there is a problem of limiting the degree of freedom of the CA configuration or increasing the signaling burden.

[0168] [Operation Method 2]

[0169] Two TRPs with different PCIs can be operated in a single serving cell configuration.

[0170] The base station can configure channels and signals transmitted from different TRPs through a single serving cell configuration via [Operation Method 2]. Since the terminal operates based on a single ServCellIndex (e.g., ServCellIndex #1), it is impossible for it to recognize the PCI assigned to the second TRP (e.g., PCI #2). [Operation Method 2] may have greater freedom in CA configuration compared to the aforementioned [Operation Method 1], but if multiple SSBs are transmitted from TRP 1 and TRP 2, the SSBs will have different PCIs (e.g., PCI #1 and PCI #2), and the base station may be unable to map the PCI of the second TRP (e.g., PCI #2) through the ServCellIndex indicated by the cell parameter in QCL-Info. The base station may only be able to designate the SSB transmitted from TRP 1 as the source reference RS of the QCL configuration information, and it may be impossible to designate the SSB transmitted from TRP 2.

[0171] As described above, [Operation Method 1] can perform multi-TRP operation for two TRPs with different PCIs through additional serving cell settings without additional specification support, but [Operation Method 2] can operate based on the following additional terminal capability reports and base station configuration information.

[0172] Regarding terminal capability reporting for [Operation Method 2]

[0173] - The terminal can report to the base station via terminal capability that configuration for the serving cell's PCI and other additional PCIs is possible through upper-layer signaling from the base station. Such terminal capability may include two independent numbers, X1 and X2, or each X1 and X2 may be reported as an independent terminal capability.

[0174] - X1 represents the maximum number of additional PCIs that can be configured for the terminal, and the PCI may differ from the PCI of the serving cell; in this case, it refers to a situation where the time domain position and periodicity of the SSB corresponding to the additional PCI are the same as those of the serving cell's SSB.

[0175] - X2 represents the maximum number of additional PCIs that can be configured for the terminal, and in this case, the PCI may differ from the PCI of the serving cell. In this case, the time domain position and periodicity of the SSB corresponding to the additional PCI may differ from the SSB corresponding to the PCI reported as X1.

[0176] - By definition, PCIs corresponding to the values ​​reported as X1 and X2 cannot be set simultaneously.

[0177] - The values ​​reported as X1 and X2 through the terminal capability report can each have one integer value from 0 to 7.

[0178] - The values ​​reported as X1 and X2 may differ from the values ​​reported in FR1 and FR2.

[0179] Regarding upper layer signaling settings for [Operation Method 2]

[0180] - Based on the terminal capability report described above, the terminal may receive an upper layer signaling, SSB-MTCAdditionalPCI-r17, from the base station, and the upper layer signaling may include at least a plurality of additional PCIs having values ​​different from the serving cell, an SSB transmission power corresponding to each additional PCI, and an ssb-PositionInBurst corresponding to each additional PCI, and the maximum number of additional PCIs that can be set may be 7.

[0181] - As an assumption regarding the SSB corresponding to an additional PCI of a different value from the serving cell, the terminal may be assumed to have the same center frequency, subcarrier spacing, and subframe number offset as the SSB of the serving cell.

[0182]

[0183] *160- The terminal may assume that the reference RS (e.g., SSB or CSI-RS) corresponding to the PCI of the serving cell is always connected to an active TCI state, and in the case of additionally configured PCIs having values ​​different from the serving cell, when there is one or more PCIs, it may assume that only one of those PCIs is connected to an active TCI state.

[0184] - If a terminal is configured with two different coresetPoolIndexes, and a reference RS corresponding to a serving cell PCI is connected to one or more active TCI states, and a reference RS corresponding to an additionally configured PCI having a different value from the serving cell is connected to one or more active TCI states, the terminal can expect that the active TCI state(s) connected to the serving cell PCI are connected to one of the two coresetPoolIndexes, and the active TCI state(s) connected to the additionally configured PCI having a different value from the serving cell are connected to the other coresetPoolIndex.

[0185] The terminal capability reporting and upper layer signaling of the base station for the above-described [Operation Method 2] can set an additional PCI with a value different from the PCI of the serving cell. If the above setting does not exist, the SSB corresponding to the additional PCI with a value different from the PCI of the serving cell, which cannot be designated as a source reference RS, can be used to designate it as the source reference RS of the QCL setting information. Furthermore, unlike the SSB that can be set for use in purposes such as RRM, mobility, or handover, such as the setting information for the SSB that can be set within the upper layer signaling smtc1 and smtc2, it can be used to serve as a QCL source RS to support multiple TRP operations having different PCIs.

[0186] Next, we will explain in detail the demodulation reference signal (DMRS), which is one of the reference signals in the 5G system.

[0187] A DMRS may consist of multiple DMRS ports, and each port maintains orthogonality using CDM (code division multiplexing) or FDM (frequency division multiplexing) to prevent interference with one another. However, the term DMRS may be expressed using other terms depending on the user's intent and the purpose of use of the reference signal. The term DMRS is provided merely as a specific example to facilitate the explanation of the technical content of this disclosure and to aid in understanding the disclosure, and is not intended to limit the scope of this disclosure. In other words, it is obvious to those skilled in the art that the technical concept of this disclosure can be implemented with any reference signal.

[0188] FIG. 8 illustrates an example explaining DMRS patterns (type 1 and type 2) used for communication between a base station and a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0189] Two DMRS patterns can be supported in 5G systems.

[0190] Referring to FIG. 8, DMRS type 1 (801, 802) is illustrated, specifically 1 symbol pattern (801) and 2 symbol pattern (802). DMRS type 1 (801, 802) is a DMRS pattern with a comb 2 structure and can be composed of two CDM groups (CDM group 0, CDM group 1), and different CDM groups can be FDM.

[0191] In 1 symbol pattern (801), frequency-phase CDM is applied to the same CDM group to distinguish two DMRS ports, thus allowing a total of four orthogonal DMRS ports to be configured. 1 symbol pattern (801) may include DMRS port IDs mapped to each CDM group (DMRS port IDs for the downlink may be indicated by the illustrated number + 1000). In 2 symbol pattern (802), time / frequency-phase CDM is applied to the same CDM group to distinguish four DMRS ports, thus allowing a total of eight orthogonal DMRS ports to be configured. 2 symbol pattern (802) may include DMRS port IDs mapped to each CDM group (DMRS port IDs for the downlink may be indicated by the illustrated number + 1000).

[0192] Referring to FIG. 8, DMRS type 2 (803, 804) is illustrated, and as a DMRS pattern structure in which FD-OCC (frequency domain orthogonal cover codes) is applied to frequency-adjacent subcarriers, it can be composed of three CDM groups (CDM group 0, CDM group 1, CDM group 2), and different CDM groups can be FDM.

[0193] In 1 symbol pattern (803), frequency-phase CDM is applied to the same CDM group to distinguish two DMRS ports, thus allowing a total of six orthogonal DMRS ports to be configured. 1 symbol pattern (803) may include DMRS port IDs mapped to each CDM group (DMRS port IDs for the downlink may be indicated as the illustrated number + 1000). In 2 symbol pattern (704), time / frequency-phase CDM is applied to the same CDM group to distinguish four DMRS ports, thus allowing a total of twelve orthogonal DMRS ports to be configured. 2 symbol pattern (804) may include DMRS port IDs mapped to each CDM group (DMRS port IDs for the downlink may be indicated as the illustrated number + 1000).

[0194] As described above, in an NR system, two different DMRS patterns (e.g., DMRS type 1 (801, 802) or DMRS type 2 (803, 804)) can be configured, and each DMRS pattern can be configured to be either a one-symbol pattern (801, 803) or an adjacent two-symbol pattern (802, 804). Additionally, in an NR system, not only are DMRS port numbers scheduled, but the number of CDM groups scheduled together for PDSCH rate matching can also be configured and signaled. Furthermore, in the case of CP-OFDM (cyclic prefix based orthogonal frequency division multiplex), both of the two DMRS patterns described above may be supported in DL and UL, while in the case of DFT-S-OFDM (discrete Fourier transform spread OFDM), only DMRS type 1 (801, 802) among the DMRS patterns described above may be supported in UL.

[0195] Additionally, support may be provided to configure additional DMRS. Front-loaded DMRS refers to the first DMRS transmitted and received at the earliest symbol in the time domain among the DMRS, and additional DMRS refers to the DMRS transmitted and received at a symbol later than the front-loaded DMRS in the time domain. In an NR system, the number of additional DMRS can be configured from a minimum of 0 to a maximum of 3. Additionally, when additional DMRS is configured, the same pattern as the front-loaded DMRS may be assumed. In one embodiment, regarding the front-loaded DMRS, if information is provided on whether the aforementioned DMRS pattern type is type 1 or type 2, whether the DMRS pattern is a one-symbol pattern or an adjacent two-symbol pattern, and information on the number of DMRS ports and CDM groups used, then when additional DMRS is configured, it may be assumed that the additional DMRS has the same DMRS information as the front-loaded DMRS.

[0196] In one embodiment, the aforementioned downlink DMRS setting can be set through RRC signaling as shown in [Table 6] below.

[0197] [Table 6]

[0198]

[0199] Here, dmrs-Type can set the DMRS type, dmrs-AdditionalPosition can set additional DMRS OFDM symbols, maxLength can set a 1-symbol DMRS pattern or a 2-symbol DMRS pattern, scramblingID0 and scramblingID1 can set scrambling IDs, and phaseTrackingRS can set the PTRS (phase tracking reference signal).

[0200] In addition, the aforementioned uplink DMRS settings can be configured through RRC signaling as shown in [Table 7] below.

[0201] [Table 7]

[0202]

[0203] Here, dmrs-Type can set the DMRS type, dmrs-AdditionalPosition (additional DMRS OFDM symbols) can be set, phaseTrackingRS can set PTRS, and maxLength can set a 1-symbol DMRS pattern or a 2-symbol DMRS pattern. scramblingID0 and scramblingID1 can set scrambling IDs, nPUSCH-Identity can set the cell ID for DFT-s-OFDM, sequenceGroupHopping can disable sequence group hopping, and sequenceHopping can enable sequence hopping.

[0204] FIG. 9 illustrates an example of channel estimation using DMRS received from one PUSCH in the time band of a wireless communication system according to one embodiment of the present disclosure.

[0205] Referring to Fig. 9, when performing channel estimation for data decoding using DMRS, in the frequency band, channel estimation can be performed within the precoding resource block group (PRG), which is the bundling unit, by using physical resource blocks (PRB) bundling linked to the system band. In addition, in the time unit, the channel can be estimated by assuming that only DMRS received from a single PUSCH has the same precoding.

[0206] The following describes the time domain resource allocation (TDRA) method for data channels in a 5G communication system. A base station can set a time domain resource allocation information table for a physical downlink shared channel (PDSCH) and a physical uplink shared channel (PUSCH) for a terminal using upper layer signaling (e.g., RRC signaling).

[0207] The base station may set up a table for PDSCH consisting of a maximum of maxNrofDL-Allocations = 17 entries, and for PUSCH, a table consisting of a maximum of maxNrofUL-Allocations = 17 entries. Time domain resource allocation information may include, for example, PDCCH-to-PDSCH slot timing (corresponding to a slot-unit time interval between the time when PDCCH is received and the time when the PDSCH scheduled by the received PDCCH is transmitted, denoted as K0) or PDCCH-to-PUSCH slot timing (corresponding to a slot-unit time interval between the time when PDCCH is received and the time when the PUSCH scheduled by the received PDCCH is transmitted, denoted as K2), information on the position and length of the starting symbol for which PDSCH or PUSCH is scheduled within the slot, and at least one of the mapping type of PDSCH or PUSCH.

[0208] In one embodiment, time domain resource allocation information for PDSCH can be set to the terminal through RRC signaling as shown in [Table 8] below.

[0209] [Table 8]

[0210]

[0211] Here, k0 represents the PDCCH-to-PDSCH timing (i.e., the slot offset between DCI and its scheduled PDSCH) in slots, mappingType represents the PDSCH mapping type, startSymbolAndLength represents the starting symbol and length of the PDSCH, and repetitionNumber represents the number of PDSCH transmission occasions according to the slot-based repetition method.

[0212] In one embodiment, time domain resource allocation information for PUSCH can be set to the terminal through RRC signaling as shown in [Table 9] below.

[0213] [Table 9]

[0214]

[0215] Here, k2 represents the PDCCH-to-PUSCH timing (i.e., the slot offset between DCI and the scheduled PUSCH) in slots, mappingType represents the PUSCH mapping type, startSymbolAndLength or StartSymbol and length represents the starting symbol and length of the PUSCH, and numberOfRepetitions represents the number of repetitions applied to the PUSCH transmission.

[0216] A base station may indicate to a terminal at least one of the entries in a table for time domain resource allocation information via L1 signaling (e.g., downlink control information (DCI)) (e.g., by indicating the 'time domain resource allocation' field within the DCI). Based on the DCI received from the base station, the terminal may obtain time domain resource allocation information for PDSCH or PUSCH.

[0217] The following describes the transmission of the physical uplink shared channel (PUSCH) in a 5G system. PUSCH transmission can be dynamically scheduled by a UL grant within the DCI (e.g., referred to as DG (dynamic grant)-PUSCH) or by a configured grant Type 1 or configured grant Type 2 (e.g., referred to as CG (configured grant)-PUSCH). Dynamic scheduling for PUSCH transmission can be indicated, for example, by DCI format 0_0 or 0_1.

[0218] A PUSCH transmission of a Configured grant Type 1 can be configured semi-statically by receiving a configuredGrantConfig containing the rrc-ConfiguredUplinkGrant of [Table 10] via upper-layer signaling, without receiving a UL grant within the DCI. A PUSCH transmission of a Configured grant Type 2 can be scheduled semi-persistently by a UL grant within the DCI after receiving a configuredGrantConfig that does not contain the rrc-ConfiguredUplinkGrant of [Table 10] via upper-layer signaling.

[0219] In one embodiment, when a PUSCH transmission is scheduled by a configured grant, the parameters applied to the PUSCH transmission may be set through the configuredGrantConfig, an upper-layer signaling of [Table 10], excluding specific parameters provided by the pusch-Config of [Table 11], an upper-layer signaling (e.g., dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, or scaling of UCI-OnPUSCH). For example, if a terminal is provided with a transformPrecoder within the configuredGrantConfig, an upper-layer signaling of [Table 10], the terminal may apply tp-pi2BPSK within the pusch-Config of [Table 11] to the PUSCH transmission operated by the configured grant.

[0220] [Table 10]

[0221]

[0222] Next, the PUSCH transmission method is described. The DMRS antenna port for PUSCH transmission may be the same as the antenna port for SRS transmission. PUSCH transmission may follow a codebook-based transmission method and a non-codebook-based transmission method, respectively, depending on whether the value of txConfig in pusch-Config in [Table 11], the upper signaling, is 'codebook' or 'nonCodebook'. As described above, PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1 and can be semi-statically configured by a configured grant.

[0223] If the terminal is instructed to schedule a PUSCH transmission via DCI format 0_0, the terminal may perform beam configuration for the PUSCH transmission using a pucch-spatialRelationInfoID corresponding to a terminal-specific (UE-specific, dedicated) PUCCH resource having the lowest ID within an active uplink bandwidth part (BWP) in the serving cell. In one embodiment, the PUSCH transmission may be performed based on a single antenna port. The terminal may not expect to schedule a PUSCH transmission via DCI format 0_0 within a BWP where a PUCCH resource containing pucch-spatialRelationInfo is not configured. If the terminal is not configured with txConfig in pusch-Config of [Table 11], the terminal may not expect to be scheduled via DCI format 0_1.

[0224] [Table 11]

[0225]

[0226] Next, codebook-based PUSCH transmission is described. Codebook-based PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1 and can operate semi-statically via a configured grant. When Codebook-based PUSCH is dynamically scheduled via DCI format 0_1 ​​or semi-statically configured via a configured grant, the terminal can determine a precoder for PUSCH transmission based on the SRS resource indicator (SRI), TPMI (transmission precoding matrix indicator), and transmission rank (number of PUSCH transmission layers).

[0227] According to one embodiment of the present disclosure, the SRI may be provided through the field SRS resource indicator within the DCI or set through the higher-level signaling srs-ResourceIndicator. The terminal may receive at least one SRS resource during codebook-based PUSCH transmission, and, for example, may receive up to two. When the terminal receives the SRI through the DCI, the SRS resource indicated by the said SRI may refer to the SRS resource corresponding to the SRI among the SRS resources transmitted prior to the PDCCH containing the said SRI. Additionally, the TPMI and transmission rank may be provided through the field precoding information and number of layers within the DCI or set through the higher-level signaling precodingAndNumberOfLayers. The TPMI may be used to indicate the precoder applied to the PUSCH transmission.

[0228] A precoder to be used for PUSCH transmission may be selected from an uplink codebook having the same number of antenna ports as the nrofSRS-Ports value in the upper signaling SRS-Config. In codebook-based PUSCH transmission, the terminal may determine the codebook subset based on TPMI and the codebookSubset in the upper signaling pusch-Config. In one embodiment, the codebookSubset in the upper signaling pusch-Config may be set to one of 'fullyAndPartialAndNonCoherent', 'partialAndNonCoherent', or 'nonCoherent' based on the UE capability reported by the terminal to the base station.

[0229] If the terminal reports 'partialAndNonCoherent' as a UE capability, the terminal may not expect the value of the parent signaling codebookSubset to be set to 'fullyAndPartialAndNonCoherent'. Additionally, if the terminal reports 'nonCoherent' as a UE capability, the terminal may not expect the value of the parent signaling codebookSubset to be set to 'fullyAndPartialAndNonCoherent' or 'partialAndNonCoherent'. If nrofSRS-Ports within the parent signaling SRS-ResourceSet points to two SRS antenna ports, the terminal may not expect the value of the parent signaling codebookSubset to be set to 'partialAndNonCoherent'.

[0230] A terminal can receive one SRS resource set in which the value of usage within the upper signaling SRS-ResourceSet is set to 'codebook', and one SRS resource within that SRS resource set can be indicated via SRI. If multiple SRS resources are configured within the SRS resource set in which the value of usage within the upper signaling SRS-ResourceSet is set to 'codebook', the terminal can expect that the value of nrofSRS-Ports within the upper signaling SRS-Resource will be set to the same value for all SRS resources.

[0231] A terminal transmits one or more SRS resources included in an SRS resource set in which the value of usage is set to 'codebook' according to upper signaling to a base station, and the base station may select one of the SRS resources transmitted by the terminal and instruct the terminal to perform PUSCH transmission using the transmit beam information of the corresponding SRS resource. In one embodiment, in codebook-based PUSCH transmission, an SRI is used as information to select the index of one SRS resource and may be included in a DCI. Additionally, the base station may include information in the DCI that instructs the terminal to use for PUSCH transmission, such as the TPMI and rank, and transmit it. The terminal may perform PUSCH transmission by using the SRS resource instructed by the SRI, applying a precoder instructed by the instructed TPMI and rank based on the transmit beam of the corresponding SRS resource.

[0232] Next, non-codebook-based PUSCH transmission is described. Non-codebook-based PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1, or can operate semi-statically via a configured grant. If at least one SRS resource is configured within an SRS resource set in which the value of usage within the upper signaling SRS-ResourceSet is set to 'nonCodebook', the terminal can receive a non-codebook-based PUSCH transmission scheduled via DCI format 0_1.

[0233] For an SRS resource set in which the value of usage within the upper signaling SRS-ResourceSet is set to 'nonCodebook', the terminal can receive an NZP (non-zero power) CSI-RS resource associated with one SRS resource set. The terminal can perform calculations for a precoder for SRS transmission by measuring the NZP CSI-RS resource associated with the SRS resource set. If the difference between the last received symbol of the aperiodic NZP CSI-RS resource associated with the SRS resource set and the first symbol of the aperiodic SRS transmission at the terminal is less than a specific number of symbols (e.g., 42 symbols), the terminal may not expect the information for the precoder for SRS transmission to be updated.

[0234] If the value of resourceType within the upper signaling SRS-ResourceSet is set to 'aperiodic', the NZP CSI-RS associated with said SRS-ResourceSet may be indicated by the SRS request field within DCI format 0_1 ​​or 1_1. In one embodiment, if the NZP CSI-RS resource associated with the SRS-ResourceSet is an aperiodic NZP CSI resource and the value of the SRS request field within DCI format 0_1 ​​or 1_1 is not '00', it may indicate the existence of the NZP CSI-RS associated with the SRS-ResourceSet. The said DCI may not indicate cross-carrier or cross-BWP scheduling. If the value of the SRS request indicates the existence of the NZP CSI-RS, said NZP CSI-RS may be located in the slot where the PDCCH containing the SRS request field was transmitted. The TCI states set on the scheduled subcarrier may not be set to QCL-TypeD.

[0235] If a periodic or semi-continuous SRS resource set is configured, the NZP CSI-RS associated with said SRS resource set may be indicated through the associated CSI-RS within the parent signaling SRS-ResourceSet. For non-codebook-based transmission, the terminal may not expect the parent signaling spatialRelationInfo for the SRS resource and the associated CSI-RS within the parent signaling SRS-ResourceSet to be configured together.

[0236] When a terminal is configured with multiple SRS resources, it can determine the precoder and transmission rank to be applied to PUSCH transmission based on the SRI indicated by the base station. In one embodiment, the SRI may be indicated via a field SRS resource indicator within the DCI or configured via the srs-ResourceIndicator, which is a higher-level signaling. Similar to the codebook-based PUSCH transmission described above, when the terminal receives the SRI via the DCI, the SRS resource indicated by the SRI may refer to the SRS resource corresponding to the SRI among the SRS resources transmitted prior to the PDCCH containing the SRI. The terminal may use one or multiple SRS resources for SRS transmission, and the maximum number of SRS resources that can be transmitted simultaneously in the same symbol within a single SRS resource set and the maximum number of SRS resources may be determined by the UE capability reported by the terminal to the base station. SRS resources transmitted simultaneously by the terminal may occupy the same RB. The terminal may configure one SRS port for each SRS resource. Only one SRS resource set can be configured with the value of usage in the upper signaling SRS-ResourceSet set set to 'nonCodebook', and up to four SRS resources can be configured for non-codebook-based PUSCH transmission.

[0237] The base station transmits one NZP CSI-RS associated with an SRS resource set to the terminal, and the terminal can calculate a precoder to be used when transmitting one or more SRS resources within the SRS resource set based on the results measured upon receiving the NZP CSI-RS. When the terminal transmits one or more SRS resources within an SRS resource set where usage is set to 'nonCodebook' to the base station, it applies the calculated precoder, and the base station can select one or more SRS resources from among the received one or more SRS resources. In non-codebook-based PUSCH transmission, the SRI may represent an index capable of expressing a combination of one or more SRS resources, and the SRI may be included within the DCI. The number of SRS resources indicated by the SRI transmitted by the base station may be the number of transmission layers of the PUSCH, and the terminal can transmit the PUSCH by applying the precoder applied for SRS resource transmission to each layer.

[0238] The following describes the repetitive transmission of the uplink data channel (PUSCH) and the single TB transmission method through multiple slots in a 5G system. A 5G system can support two types of repetitive transmission methods for the uplink data channel (e.g., PUSCH repetitive transmission type A, PUSCH repetitive transmission type B) and TBoMS (TB processing over multi-slot PUSCH), which transmits a single TB across multiple slots using multiple PUSCHs. Additionally, the terminal can receive a setting for either PUSCH repetitive transmission type A or B through upper-layer signaling. Furthermore, the terminal can transmit TBoMS by receiving 'numberOfSlotsTBoMS' through a resource allocation table.

[0239] PUSCH Repeated Transmission Type A

[0240] - As described above, within a single slot, the start symbol and length of the uplink data channel are determined by the time domain resource allocation method, and the base station can transmit the number of repeated transmissions to the terminal via upper layer signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI). To determine the TBS, the number of slots N set by numberOfSlotsTBoMS is 1.

[0241] - Based on the number of repeated transmissions received from the base station, the terminal may repeatedly transmit an uplink data channel in consecutive slots that has the same starting symbol and length as the uplink data channel set above. In one embodiment, in a slot set as downlink by the base station to the terminal, or if at least one of the symbols within the slot for repeated uplink data channel transmission set by the terminal is set as downlink, the terminal may omit the transmission of the uplink data channel in that slot. For example, the terminal may not transmit the uplink data channel within the number of repeated uplink data channel transmissions. On the other hand, a terminal supporting Rel-17 repeated uplink data transmission determines a slot capable of repeated uplink data transmission as an available slot, and can count the number of transmissions when repeating the uplink data channel in a slot determined to be an available slot. If repeated uplink data channel transmission determined to be an available slot is omitted, it may be repeated through a slot capable of transmission after postponement. Using the following [Table 12], a redundancy version can be applied according to the redundancy version pattern set for each nth PUSCH transmission occasion.

[0242] PUSCH Repeated Transmission Type B

[0243] - As described above, within a single slot, the start symbol and length of the uplink data channel are determined by the time domain resource allocation method, and the base station can transmit the number of repetitions (number of repetitions) to the terminal via upper signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI). In one embodiment, the number of slots N set as numberOfSlotsTBoMS to determine the TBS is 1.

[0244] - First, based on the starting symbol and length of the uplink data channel set above, the nominal repetition of the uplink data channel can be determined as follows. Here, nominal repetition may refer to the symbol resources set by the base station for repeated PUSCH transmission, and the terminal can determine the resources available for uplink use from the set nominal repetition. In this case, the slot where the nth nominal repetition starts is The symbol given by and where nominal repetition starts in the above start slot is It can be given by. The slot where the nth nominal repetition ends is The symbol given by and where the nominal repetition ends in the last slot above is It can be given by, where n=0,…, numberofrepetitions-1, S represents the starting symbol of the configured uplink data channel, and L represents the symbol length of the configured uplink data channel. indicates the slot where the PUSCH transmission starts. can represent the number of symbols per slot.

[0245] - The terminal can determine invalid symbols for PUSCH repeat transmission type B. Symbols configured for the downlink by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated can be determined as invalid symbols for PUSCH repeat transmission type B. Additionally, invalid symbols can be set based on upper layer parameters (e.g., InvalidSymbolPattern). As an example, invalid symbols can be set by the upper layer parameters (e.g., InvalidSymbolPattern) providing a symbol-level bitmap spanning one or two slots. In one embodiment, a value marked as 1 in the bitmap may represent an invalid symbol. Additionally, the period and pattern of the bitmap can be set through upper layer parameters (e.g., periodicityAndPattern). If an upper layer parameter (e.g., InvalidSymbolPattern) is set and the InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 parameter indicates 1, the terminal may apply the invalid symbol pattern, and if it indicates 0, it may not apply the invalid symbol pattern. Alternatively, if an upper layer parameter (e.g., InvalidSymbolPattern) is set and the InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 parameter is not set, the terminal may apply the invalid symbol pattern.

[0246] - After an invalid symbol is determined in each nominal repetition, the terminal may consider the symbols excluding the determined invalid symbol as valid symbols. If one or more valid symbols are included in each nominal repetition, the nominal repetition may include one or more actual repetitions. Here, each actual repetition may refer to a symbol actually used for PUSCH repeat transmission among the symbols set in the above-mentioned nominal repetition, and may include a continuous set of valid symbols that can be used for PUSCH repeat transmission type B within a single slot. Except when the symbol length L of the configured uplink data channel is 1, the terminal may omit the transmission of the actual repetition if an actual repetition having one symbol is set as valid. Using [Table 12] below, a redundancy version may be applied according to the redundancy version pattern configured for each n-th actual repetition.

[0247] TB processing over multiple slots (TBoMS)

[0248] - As described above, the start symbol and length of the uplink data channel are determined by a time domain resource allocation method within a single slot, and the base station can transmit the number of repeated transmissions to the terminal via upper layer signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI). In one embodiment, TBS can be determined using a value of N, which is greater than or equal to 1, the number of slots set by numberOfSlotsTBoMS.

[0249] - Based on the number of slots and the number of repeated transmissions for determining the TBS received from the base station, the terminal may transmit an uplink data channel in consecutive slots that has the same starting symbol and length as the uplink data channel set above. In one embodiment, in a slot set as a downlink by the base station to the terminal, or if at least one of the symbols within the slot for repeated transmission of the uplink data channel set by the terminal is set as a downlink, the terminal may omit the transmission of the uplink data channel in that slot. For example, it may be included in the number of repeated transmissions of the uplink data channel but may not be transmitted.

[0250] On the other hand, a terminal supporting Rel-17 uplink data repeat transmission determines that a slot capable of uplink data repeat transmission is an available slot, and the number of transmissions for the slot determined to be an available slot can be counted during uplink data channel repeat transmission. If the uplink data channel repeat transmission determined to be an available slot is omitted, it can be repeated through a slot that is available for transmission after postponement. In one embodiment, using [Table 12] below, a redundancy version may be applied according to the redundancy version pattern set for each nth PUSCH transmission occasion.

[0251] rv id indicated by the DCI scheduling the PUSCHrv id to be applied to n th transmission occasion (repetition Type A) or TB processing over multiple slots) or n thactual repetition (repetition Type B)((n-(n mod N)) / N) mod 4 = 0((n-(n mod N)) / N) mod 4 = 0((n-(n mod N)) / N) mod 4 = 0((n-(n mod N)) / N) mod 4 = 000231223103310211023

[0252] The following describes a method for determining an uplink available slot for a single or multiple PUSCH transmission in a 5G system. According to one embodiment of the present disclosure, when a terminal is configured to enable AvailableSlotCounting, the terminal can determine an available slot for Type A PUSCH repeated transmission and TBoMS PUSCH transmission based on the tdd-UL-DL-ConfigurationCommon, tdd-UL-DL-ConfigurationDedicated, ssb-PositionsInBurst, and TDRA (time domain resource allocation) information field value. That is, if at least one symbol configured as TDRA for PUSCH in a slot for PUSCH transmission overlaps with at least one symbol for a purpose other than uplink transmission, the slot may be determined as an unavailable slot.

[0253] The following describes a method to reduce SSB density through dynamic signaling for base station energy saving in 5G systems.

[0254] FIG. 10 illustrates a method for resetting SSB transmission through dynamic signaling of a wireless communication system according to one embodiment of the present disclosure.

[0255] Referring to FIG. 10, the terminal can receive ssb-PositionsInBurst = '11110000' (1002) from the base station through upper layer signaling (SIB1 or ServingCellConfigCommon). At a subcarrier interval of 30 kHz, up to two synchronization signal blocks can be transmitted within a time of 0.5 ms (or corresponding to the length of one slot if one slot consists of 14 OFDM symbols), and accordingly, the terminal can receive four synchronization signal blocks (SSB) within a time of 1 ms (or corresponding to the length of two slots if one slot consists of 14 OFDM symbols). At this time, the base station can reset the SSB transmission setting information by broadcasting the bitmap '1010xxxx' (1004) through the Group / Cell common DCI (1003) having the nwes-RNTI (network energy saving-Radio Network Temporary Identifier) ​​(or es-RNTI) to reduce the density of SSB transmission for energy saving. At this time, the transmission of SS block #1 (1005) and SS block #3 (1006) can be canceled based on the bitmap (1004) set by the Group / Cell common DCI. FIG. 10 illustrates a method (1001) for resetting SSB transmission through the bitmap-based group / Cell common DCI.

[0256] Additionally, the base station can reset the SSB-periodicity set via upper-layer signaling through the Group / Cell common DCI. Furthermore, by additionally setting Timer information to indicate the application time of the Group / Cell common DCI, the base station can transmit SSBs using the SSB transmission information reset via the Group / Cell common DCI during the set timer. After the timer ends, the base station can operate using the SSB transmission information set via the existing upper-layer signaling. This allows the setting to be switched from normal mode to energy-saving mode via the timer, thereby resetting the SSB configuration information. Alternatively, the base station can set the application time and duration of the SSB configuration information reset via the Group / Cell common DCI to the terminal using Offset and Duration information. In this case, the terminal may not monitor SSBs for the Duration period, starting from the moment the Group / Cell common DCI is received and the moment the Offset is applied.

[0257] The following describes BWP or BW adaptation methods through dynamic signaling for base station energy saving in 5G systems.

[0258] FIG. 11 illustrates a method for resetting BWP and BW through dynamic signaling of a wireless communication system according to one embodiment of the present disclosure.

[0259] Referring to FIG. 11, the terminal can operate as an activated BWP or BW through upper layer signaling and L1 signaling from the base station (1101). For example, a fixed power PSD B It can operate via a full 100MHz bandwidth. In this case, the base station uses an equal power PSD for energy saving. BWith this, the BW and BWP can be adjusted to enable a narrower BW of 40 MHz for the terminal (1102). At this time, the adjustment operation of the BW or BWP for energy saving of the base station can be set to match the BWP and BW settings specifically set for the UE through the Group common DCI and Cell specific DCI (1103). For example, UE#0 and UE#1 may have different BWP configurations and locations. At this time, the BW and BWP of all terminals can be set to one identically to save energy by reducing the BW used by the base station. At this time, the BWP or BW in the operation for energy saving can be set to one or more, and this can be used to set the BWP per UE Group.

[0260] In describing the present disclosure, the term "upper layer signaling" may refer to a signaling corresponding to at least one or a combination of at least one of the following signalings.

[0261] - MIB (Master Information Block)

[0262] - SIB (System Information Block) or SIB

[0263] - RRC (Radio Resource Control)

[0264] - MAC (Medium Access Control) CE (Control Element)

[0265] In addition, L1 signaling may be a signaling corresponding to at least one or a combination of at least one of the following physical layer channels or signaling methods using signaling.

[0266] - PDCCH (Physical Downlink Control Channel)

[0267] - DCI (Downlink Control Information)

[0268] - Terminal-specific (UE-specific) DCI

[0269] - Group common DCI

[0270] - Common DCI

[0271] - Scheduling DCI (e.g., DCI used for the purpose of scheduling downlink or uplink data)

[0272] - Non-scheduling DCI (e.g., DCI not intended for scheduling downlink or uplink data)

[0273] - PUCCH (Physical Uplink Control Channel)

[0274] - UCI (Uplink Control Information)

[0275] In the following disclosure, the examples are described through a plurality of embodiments, but these are not independent, and one or more embodiments may be applied simultaneously or in combination.

[0276] The following describes a DRX alignment method using dynamic signaling for base station energy saving in 5G systems.

[0277] FIG. 12 illustrates a method for resetting DRX through dynamic signaling of a wireless communication system according to one embodiment of the present disclosure.

[0278] Referring to FIG. 12, the base station can set the DRX specifically for the UE through upper layer signaling. For example, different drx-LongCycle (1202) or drx-ShortCycle, drx-onDurationTimer (1203) and drx-InactivityTimer (1204) can be set for each terminal. Subsequently, for energy saving, the base station can set the UE-specific DRX settings specifically for the UE group or cell through L1 signaling (1201). Through this, the base station can obtain the same effect for energy saving as the terminal saves power through the DRX.

[0279] The following illustrates an example describing Discontinuous transmission (DTx, DTX) operations to reduce energy consumption of base stations in a 5G system.

[0280] FIG. 13 is a diagram illustrating a DTx method for base station energy saving according to one embodiment of the present disclosure.

[0281] Referring to FIG. 13, the base station can set DTx for energy saving through upper layer signaling (e.g., new system information block (SIB) for DTx or RRC signaling) and L1 signaling (e.g., DCI). At this time, the base station may set a dtx-onDurationTimer (1305) for transmitting a reference signal for measuring RRM measurement, beam management, path loss, etc., for scheduling a DL SCH (shared channel) for DTx operation, a dtx-InactivityTimer (1306) for receiving a PDSCH after receiving a PDCCH for scheduling a DL SCH, a synchronization signal (SS) (1303) for synchronization before the dtx-onDurationTimer, a dtx-offset (1304) for setting an offset between the dtx-onDurationTimer and the dtx-onDurationTimer after the setting information, and a dtx-(Long)Cycle (1302) for DTx to operate periodically based on the setting information. At this time, the dtx-cycle (1302) may be set to multiple long cycles and short cycles. During DTx operation, the base station considers the transmitter to be off (or inactive) and therefore may not transmit DL CCH, SCH, and DL RS. That is, during DTx operation, the base station may transmit downlink (e.g., PDCCH, PDSCH, RS, etc.) only during SS, dtx-onDurationTimer, and dtx-InactivityTimer. At this time, as additional information for the configured SS, SS-gapbetweenBurst (the gap between SS bursts in the time domain) or the number of SS bursts may be additionally configured.

[0282] The following describes a method for activating a base station via a gNB wake-up signal (WUS) during the base station's inactive mode to reduce energy consumption in a 5G system.

[0283] FIG. 14 illustrates an example explaining the operation of a base station according to a gNB WUS according to one embodiment of the present disclosure.

[0284] Referring to FIG. 14, the base station may keep the transmitter in an Off (or inactive) state during the base station's inactive state (or sleep mode) for energy saving. Subsequently, the base station may receive a gNB WUS (1402) from the terminal to activate the base station's sleep mode. Subsequently, when the base station receives a WUS from the terminal via the Rx terminal, it may change the Tx terminal to an On (or active) state (1403). Subsequently, the base station may perform downlink transmission to the terminal. At this time, the base station may perform synchronization after Tx is turned on and perform Control and Data transmission. In addition, various uplink signals, such as PRACH (physical random access channel), scheduling request (SR PUCCH), PUCCH including Ack, etc., may be considered as gNB WUS. Through the above method, the base station can save energy, and at the same time, the terminal can improve latency.

[0285] At this time, the base station may set a WUS occasion for receiving the gNB WUS and a Sync RS for synchronization before the terminal transmits the gNB WUS. At this time, the Sync RS may be considered as an SSB, TRS (tracking reference signal), Light SSB (PSS+SSS), consecutive SSBs, or new RS (continuous PSS + SSS), and the WUS may be considered as a PRACH, PUCCH with SR, or sequence-based signal. The Sync RS (1404) for the terminal to activate the base station's energy-saving disable mode and the WUS occasion for receiving the WUS may be transmitted repeatedly with WUS-RS periodicity (1405). In the case of FIG. 14, one embodiment is described with an example of a 1-to-1 mapping between the Sync RS and the WUS occasion, but the present disclosure is not limited thereto. For example, the Sync and WUS occasion may be N-to-1 mapped, 1-to-N mapped, or N-to-M mapped.

[0286] The following describes a method for dynamically turning on / off the Spatial domain elements (i.e., Antenna, power amplifier (PA), or TxRUs (transceiver units or transmission radio units)) of a base station to save base station energy in a 5G system.

[0287] FIG. 15 is a diagram illustrating an antenna adaptation method for a base station for energy saving of a wireless communication system according to one embodiment of the present disclosure.

[0288] Referring to FIG. 15, the base station can adjust the number of Tx antenna ports per RU (radio unit) for network energy savings (NWES) (1501). For example, since the power amplifier (PA) of the base station accounts for most of the base station's energy consumption, the base station can turn off the Tx antenna to save energy. At this time, the base station may refer to / use the terminal's RSRP (reference signal received power), CQI (channel quality indicator), and RSRQ (reference signal received quality) to determine whether the Tx antenna can be turned off. The base station can transmit Tx by adjusting the number of activated Tx antennas per UE group or per UE. At this time, the base station may set information including one or more of beam information or Reference Signal information (e.g., one or more of CSI resource, CSI resource set, or CSI report) according to the antenna on / off to the terminal through upper layer signaling (e.g., RRC signaling) or DCI signaling. In addition, the base station can set different antenna information for each BWP and reset the antenna information in response to changes in the BWP. Furthermore, the base station can receive CSI feedback from the terminal to determine the feasibility of spatial domain (SD) adaptation. The base station can determine SD adaptation (based on the CSI feedback). The base station can receive multiple feedback from the terminal through antenna structure hypotheses of various antenna patterns for SD adaptation.

[0289] More specifically, the base station may apply multiple types of SD adaptation (e.g., two types) for energy saving (1502). For example, the multiple types may include Type 1 SD adaptation (1503) and Type 2 SD adaptation (1504).

[0290] When Type 1 SD adaptation (1503) is applied, the base station can adapt the number of antenna ports while maintaining the number of physical antenna elements per antenna port (i.e., logical port). At this time, the RF characteristics (e.g., tx power, beam) per port can be the same. Therefore, the terminal can combine the CSI-RS of the same port during CSI measurements (e.g., L1-RSRP (layer 1-RSRP), L3-RSRP (layer 3-RSRP), etc.).

[0291] In another way, when Type 2 SD adaptation (1504) is applied, the base station can turn on / off physical antenna elements per port with the same number of antenna ports (i.e., logical ports) (1504). In this case, the RF characteristics per port may differ. During CSI measurement, the terminal can distinguish the CSI-RS of the same port and perform measurements for each. The base station can save energy through one or more of a plurality of types of SD adaptation methods, including the two types of SD adaptation methods mentioned above.

[0292] The following describes a method for a base station to vary SSB transmission for energy saving in a 5G system. The first method involves the base station instructing the terminal that an on-demand SSB is being transmitted to activate the S-cell in situations where there is no periodic SSB transmission or there is a long-period SSB transmission in the S-cell, and then transmitting the on-demand SSB. In the first method, since on-demand SSB transmission can be performed only when necessary, the base station's energy can be saved. The second method involves changing the period (or SSB adaptation) for the SSB that is periodically transmitted in a cell (P-cell, PS-cell, or S-cell). For example, the period for the SSB can be changed by setting candidate values ​​for changing the SSB transmission period via an upper signal and instructing the terminal to specify one of the candidate values. Alternatively, the period for the SSB can be changed by setting multiple SSB configuration information, including the transmission period, via an upper signal and instructing the terminal to specify one of the settings. In the second method above, the energy of the base station can be saved by changing the period to a small value to transmit SSB frequently when SSB transmission is required, and changing the period to a long value to transmit SSB infrequently when SSB transmission is not required.

[0293] Unless otherwise specifically noted, the on-demand SSB described below may be received by a terminal capable of receiving on-demand SSB settings and instructions and receiving the on-demand SSB, and the on-demand SSB may be transmitted by a base station capable of transmitting settings and instructions for the on-demand SSB and transmitting the on-demand SSB.

[0294] In addition, the SSB adaptation described below may be received by a terminal having the ability to receive SSB adaptation settings and instructions and to receive an SSB of a changed period, and the said SSB may be transmitted by a base station having the ability to transmit settings and instructions for the SSB adaptation and to transmit an SSB of a changed period.

[0295] First, using FIGS. 16 and 17, a method for setting up and receiving instructions for on-demand SSB transmission for energy saving of the base station and on-demand SSB reception of the terminal in the first method above will be explained.

[0296] FIG. 16 is a diagram illustrating an example of on-demand SSB operation in a situation where an S-cell (secondary cell, SCell) is set up for a terminal but is not yet activated, according to one embodiment of the present disclosure.

[0297] FIG. 16 illustrates the transmission of an on-demand SSB in a situation where, after a terminal has connected to a primary cell (PCell), the terminal possessing carrier aggregation (CA) capability receives a configuration for an S-cell (or information related to the configuration) from a base station and before receiving an activation instruction for the S-cell from the base station. Information regarding the transmission of the on-demand SSB (e.g., a set of information for a single on-demand SSB transmission), such as the transmission frequency position, transmission position in the time domain, transmission period, number of transmissions, transmission interval, and transmission power, can be configured for the terminal by a higher layer signaling (e.g., an RRC message). For example, when the S-cell is configured by the higher layer signal, the information regarding the on-demand SSB transmission may be configured together (i.e., the terminal may receive a higher layer signal containing information about the S-cell and information about the on-demand SSB), or it may be configured by a separate higher layer signal, distinct from the S-cell configuration.

[0298] According to one embodiment, the upper signal may include a set of information for one on-demand SSB transmission or a set of information for multiple on-demand SSB transmissions. The upper signal for setting the on-demand SSB itself may indicate on-demand SSB transmission, and a signal (or information) for indicating on-demand SSB transmission may be transmitted from the base station to the terminal separately from the upper signal for setting the on-demand SSB. Hereinafter, the signal for indicating on-demand SSB transmission may correspond to information indicating that the base station transmits the on-demand SSB to the terminal, and may correspond to a signal indicating that transmission has started (or is performed) or information indicating or activating the reception of the on-demand SSB. The signal for indicating on-demand SSB transmission may be another upper signal, a MAC signal, or a physical signal. In the above, when a set of information for multiple on-demand SSB transmissions is set as a higher signal, the signal indicating an on-demand SSB transmission may indicate a specific on-demand SSB transmission by indicating one of the one or more sets or information.

[0299] According to one embodiment, the always-on SSB may correspond to an SSB defined to always be transmitted in the cell (e.g., cell defining SSB, CD-SSB), and may be configured to be transmitted at a specific frequency location (e.g., a frequency location corresponding to an on-sync raster), a specific period, or a specific time. Alternatively, depending on the configuration, the always-on SSB may not correspond to an SSB defined to always be transmitted in the cell. According to one embodiment, the on-demand SSB may correspond to an SSB that is not defined to always be transmitted in the cell (e.g., CD-SSB) (e.g., NCD-SSB or an NCD-SSB transmitted in an off-sync raster, etc.). Alternatively, depending on the configuration, the on-demand SSB may correspond to an SSB defined to be transmitted in the cell (e.g., CD-SSB or a CD-SSB transmitted in an on-sync raster).

[0300] In FIGS. 16 and 17, the downward arrow may indicate a downlink transmitted from the base station to the terminal, and the upward arrow may indicate an uplink transmitted from the terminal to the base station.

[0301] According to FIG. 16, Case #1 illustrates a situation where an always-on SSB, which is always transmitted periodically, is not transmitted from the S-cell or another reference cell for the S-cell (for the purpose of energy saving at the base station, etc.). In Case #1, rapid S-cell activation may not be possible because there is no always-on SSB, which is always transmitted periodically for the S-cell (which may refer to the synchronization signal blocks described in FIG. 4 to 7, specifically the synchronization signal block that indicates the SIB1 reception resource in the PBCH within the synchronization signal block). In this case, an on-demand SSB may be used to rapidly activate the S-cell. In Case #1, the terminal receives an on-demand SSB setting and / or instruction from the base station and can perform a measurement on the S-cell by receiving the on-demand SSB. By reporting the channel status to the base station through the on-demand SSB measurement, the terminal or the base station can determine that the S-cell is in a known state rather than an unknown state. If an activation instruction for the S-cell is received from the base station, rapid S-cell activation may be possible by receiving a temporary RS or CSI-RS QCLed to the on-demand SSB and reporting the corresponding CSI to the base station.

[0302] According to FIG. 16, Case #2 illustrates a situation in which an always-on SSB, which is transmitted periodically, is transmitted from an S-cell or from another reference cell for the S-cell. In Case #2, although an always-on SSB is always transmitted for the S-cell, it is transmitted at a period too long (e.g., longer than the period for S-cell measurement according to one embodiment) (for the sake of energy saving at the base station, etc.), so rapid S-cell activation may not be possible because it is difficult for the terminal to measure the S-cell based on the always-on SSB. At this time, an on-demand SSB according to one embodiment of the present disclosure may be used to rapidly activate the S-cell. In Case #2, the terminal receives an on-demand SSB setting and / or instruction from the base station and receives the on-demand SSB to perform a measurement of the S-cell. By reporting the channel status to the base station through the on-demand SSB measurement, the terminal or the base station can determine that the S-cell is in a known state from an unknown state. If an activation instruction for the S-cell is received from the base station, rapid S-cell activation may be possible by receiving a temporary RS or CSI-RS QCLed to the on-demand SSB and reporting the corresponding CSI to the base station.

[0303] FIG. 17 is a diagram illustrating an example of on-demand SSB operation in a situation where an activation instruction for an S cell is received according to an embodiment of the present disclosure.

[0304] FIG. 17 illustrates a situation in which, after a terminal has connected to a P-cell, a terminal having carrier aggregation capability receives a configuration for an S-cell from a base station, and then receives an activation instruction for an S-cell from a base station, an instruction that an on-demand SSB is transmitted is transmitted through a time resource (or time position, same OFDM symbol, or same slot) that is the same time resource as the time resource in which the activation instruction was received. Information regarding on-demand SSB transmission, such as the transmission frequency position of the on-demand SSB, the transmission position in the time domain, the transmission period, the number of transmissions, the transmission interval, the transmission power, etc. (e.g., a set of information for a single on-demand SSB transmission), may be configured for the terminal by a higher signal. For example, when the S-cell is configured by a higher signal, the information regarding the on-demand SSB transmission may be configured together (i.e., the terminal may receive a higher signal containing information about the S-cell and information about the on-demand SSB), or it may be configured by a separate higher signal, separated from the S-cell configuration.

[0305] According to one embodiment, the upper signal may include a set of information for one on-demand SSB transmission or a set of information for multiple on-demand SSB transmissions. The upper signal for setting the on-demand SSB itself may indicate on-demand SSB transmission, and a signal indicating on-demand SSB transmission may be transmitted from the base station to the terminal separately from the upper signal for setting the on-demand SSB. The signal indicating on-demand SSB transmission may be another upper signal, a MAC signal, or a physical signal. Alternatively, information indicating on-demand SSB transmission may be included in a signal indicating S-cell activation, and the signal indicating on-demand SSB transmission may be a separate signal from the signal indicating S-cell activation. In the above, when a set of information for multiple on-demand SSB transmissions is set as a higher signal, the signal indicating an on-demand SSB transmission may indicate a specific on-demand SSB transmission by indicating one of the one or more sets or information.

[0306] According to FIG. 17, Case #1 illustrates a situation where the always-on SSB, which is periodically transmitted, is not transmitted from the S-cell or another reference cell for the S-cell (for the purpose of energy saving of the base station, etc.). In Case #1, because there is no always-on SSB that is periodically transmitted for the S-cell (which may refer to the synchronization signal blocks described in FIGs. 4 to 7, specifically the synchronization signal block that indicates the SIB1 reception resource in the PBCH within the synchronization signal block), rapid S-cell activation may not be possible even if an activation instruction for the S-cell is received. In this case, an on-demand SSB may be used to rapidly activate the S-cell. In Case #1, the terminal may simultaneously receive an activation instruction for the S-cell and an on-demand SSB instruction from the base station. The terminal may then receive the on-demand SSB and perform a measurement on the S-cell. The terminal can enable rapid S-cell activation by reporting the channel status to the base station through the above-mentioned on-demand SSB measurement, or by receiving a temporary RS or CSI-RS QCLed to the above-mentioned on-demand SSB and reporting the corresponding CSI to the base station.

[0307] Next, Case #2 illustrates a situation where an always-on SSB, which is transmitted periodically, is transmitted from an S-cell or from another reference cell for the S-cell. In Case #2, although an always-on SSB is always transmitted for the S-cell, it is transmitted at a period that is too long (e.g., longer than the period for S-cell measurement according to one embodiment) (for the purpose of energy saving of the base station, etc.). Consequently, since it is difficult for the terminal to measure the S-cell based on the always-on SSB, rapid S-cell activation may not be possible even if an activation instruction for the S-cell is received. In this case, an on-demand SSB according to one embodiment of the present disclosure may be used to rapidly activate the S-cell. In Case #2, the terminal may simultaneously receive an activation instruction for the S-cell and an on-demand SSB instruction from the base station. The terminal can then receive the on-demand SSB and perform a measurement of the S-cell. The terminal can enable rapid S-cell activation by reporting the channel status to the base station through the above-mentioned on-demand SSB measurement, or by receiving a temporary RS or CSI-RS QCLed to the above-mentioned on-demand SSB and reporting the corresponding CSI to the base station.

[0308] Next, using Fig. 18, the method for setting up SSB adaptation of a terminal for energy saving of a base station in the second method and the method for receiving SSB adaptation instructions will be explained.

[0309] FIG. 18 is a diagram illustrating an example in which an adaptation of the SSB burst cycle is applied according to one embodiment of the present disclosure.

[0310] In the embodiment of FIG. 18, a situation is considered in which a terminal is set to a higher signal so that the base station can change and transmit an SSB burst having a period of 5, 20, or 80 ms.

[0311] Information regarding the transmission frequency position of the SSB burst, the transmission position in the time domain, the transmission period, the number of transmissions, the transmission interval, the transmission power, etc., and information regarding the SSB burst transmission (e.g., the SSB signal actually transmitted within a single SSB burst and the SSB index, etc.) can be set to the terminal by a higher layer signaling (e.g., SIB, RRC message, etc.). According to one embodiment, the higher layer signal may include a set of information for a single SSB burst transmission or a set of information for a plurality of changeable SSB burst transmission candidates. The higher layer signal for setting the SSB burst itself may indicate SSB transmission, and a signal (or information) for indicating SSB transmission separately from the higher layer signal for setting the SSB may be transmitted from the base station to the terminal. Hereinafter, the signal (or information) for indicating SSB transmission may correspond to information indicating that the base station transmits the SSB to the terminal, and may correspond to a signal indicating that transmission has started (or is performed) or information indicating or activating the reception of the SSB. The signal (or information) indicating the above SSB transmission may be another higher-level signal, a MAC signal, or a physical signal. In the above, when a set of information for multiple SSB transmissions is set as a higher-level signal, the signal indicating the SSB transmission may indicate a specific SSB burst transmission by indicating one of the one or more sets or information.

[0312] According to one embodiment, the SSB may correspond to an SSB defined to always be transmitted in the cell (e.g., cell defining SSB, CD-SSB), and may be configured to be transmitted at a specific frequency location (e.g., a frequency location corresponding to an on-sync raster), a specific period, or a specific time. Alternatively, depending on the configuration, the SSB may not correspond to an SSB defined to always be transmitted in the cell. According to one embodiment, the SSB may correspond to an SSB that is not defined to always be transmitted in the cell (e.g., CD-SSB) (e.g., NCD-SSB or NCD-SSB transmitted in an off-sync raster, etc.). Alternatively, depending on the configuration, the SSB may correspond to an SSB defined to be transmitted in the cell (e.g., CD-SSB or CD-SSB transmitted in an on-sync raster).

[0313] In FIG. 18, the terminal can receive an SSB burst with a period of 20ms from the base station. Accordingly, the terminal can receive an SSB burst from the base station according to the above setting. At this time, the transmission period of the SSB burst with a period of 20ms can be adapted (or changed) to a period of 5ms or a period of 80ms by the judgment of the base station.

[0314] Next, a method is proposed in which a terminal performs Radio Link Monitoring (RLM) or Beam Failure Detection (BFD) using the variable SSB when the SSB transmission is variable as shown in FIGS. 16, 17, and 18. Meanwhile, specific procedures or methods for Radio Link Monitoring or Beam Failure Detection may be based on the above description and may be interpreted in combination with the following methods using the variable SSB.

[0315] [First Plan]

[0316] Since radio link monitoring measures and evaluates whether the connection is in-sync or out-of-sync over a long period (evaluation cycle), the terminal can perform radio link monitoring based on an always-on SSB. Therefore, the terminal may not apply radio link monitoring based on an SSB with variable transmission. In this case, a variable SSB may refer to transmitting an on-demand SSB as described above, or an SSB with a changing transmission cycle (an SSB where SSB adaptation can be performed). For example, a variable SSB may include a change in the SSB cycle as a type of SSB adaptation, or, as a type of on-demand SSB, may include the transmission of an always-on SSB with a long cycle or no transmission at all, followed by the transmission of an on-demand SSB. The fact that the above radio link monitoring is not applied can be interpreted as the terminal not performing radio link monitoring based on an SSB with variable transmission, or the terminal not expecting to perform radio link monitoring based on an SSB with variable transmission.

[0317] For example, in the case of an SSB with variable transmission, there may be SSBs with the same SSB index as an always-on SSB within the SSB burst. Therefore, if radio link monitoring is configured to be performed using the SSBs with the said SSB index, the terminal may not apply radio link monitoring based on the SSB with variable transmission that has the same SSB index.

[0318] As another example, when determining the indication period for transmitting in-sync or out-of-sync results evaluated by the physical layer of the terminal to the upper layer of the terminal, SSBs with variable transmission may not be considered or may be excluded. Alternatively, if radio link monitoring is configured to be performed using SSBs with an SSB index such as an always-on SSB, the terminal may not consider or may exclude SSBs with an SSB index such as an always-on SSB and variable transmission when determining the indication period.

[0319] [Second Plan]

[0320] Since radio link monitoring measures and evaluates whether it is in-sink or out-of-sink for a long period of time (evaluation cycle), the terminal may perform radio link monitoring based on an SSB with variable transmission only when the following limitations (or conditions) are satisfied. If the conditions are not satisfied, the terminal may not perform radio link monitoring based on the SSB with variable transmission, or may not expect to perform radio link monitoring.

[0321] For example, if the adaptation of the SSB is instructed by the base station, the transmission interval of the SSB transmission can be set for the terminal by an upper signal. If the terminal determines that the transmission interval is maintained for a certain period (Y) or longer, the terminal can perform radio link monitoring based on the SSB. Y may be determined by the standard or may be set by the base station via an upper signal. Alternatively, Y may be determined as one of the timers set for radio link monitoring. For instance, Y may be a T310 timer value.

[0322] As another example, if the adaptation of the SSB is instructed by the base station, the number of transmissions of the SSB can be set to the terminal by a higher-level signal. If the terminal determines that the number of received transmissions is maintained for a certain number (Z) or longer, the terminal can perform radio link monitoring based on the SSB. Z may be determined by the standard or may be set by the base station via a higher-level signal. Alternatively, Z may be determined as one of the values ​​set for radio link monitoring. For example, Z may be the N310 value.

[0323] As another example, if the adaptation of an SSB is instructed by the base station, candidates for changeable SSB periods can be set to the terminal by a higher-level signal. Accordingly, the terminal can perform radio link monitoring based on the SSB transmitted as the intersection among the SSBs corresponding to the periods. For example, the intersection may be the SSBs determined based on the maximum value among the candidates for the set SSB periods.

[0324] As another example, the above examples can be applied to modified SSBs having an SSB index set when configuring signals for radio link monitoring.

[0325] As another example, the above examples include a setting in the signal settings for radio link monitoring that allows the changed SSBs to be used for radio link monitoring, so the terminal can perform radio link monitoring by applying the changed SSBs only when it is configured to use the changed SSBs for radio link monitoring. If the above setting is not included, the terminal may not apply the changed SSBs to radio link monitoring.

[0326] The above first and second methods may also be applied when the terminal performs Beam Failure Detection (BFD) using the variable SSB.

[0327] As another example, if the adaptation of the SSB is instructed by the base station, the transmission interval of the SSB transmission can be set to the terminal by an upper signal. If the terminal determines that the received transmission interval is maintained for a certain interval (P) or longer, the terminal can perform beam failure detection based on the SSB. P may be determined by the specifications or may be set by the base station via an upper signal. Alternatively, P may be determined as one of the timers set for beam failure detection. For example, P may be the beamFailureDetectionTimer value.

[0328] FIG. 19 is a flowchart of the operation of a terminal applying an energy saving method of a wireless communication system according to one embodiment of the present disclosure.

[0329] Various modifications may be made to the method illustrated in the flowchart of FIG. 19. For example, although illustrated as a series of steps, the various steps in each figure may overlap, occur in parallel, occur in a different order, or occur multiple times. In other examples, steps may be omitted or replaced with other steps.

[0330] Based on FIG. 19, a method is described in which a terminal uses the SSB to perform radio link monitoring or beam failure detection during an SSB transmission operation in accordance with an SSB change for energy saving by a base station.

[0331] Referring to FIG. 19, in step 1901, according to an embodiment of the present invention, the terminal may receive from a base station a setting for changing the SSB, a radio link monitoring setting, or a setting related to beam failure detection. The setting for changing the SSB may include information regarding resources for transmitting the SSB, and may include a plurality of period information, etc., to change the period of the SSB. Specific details are the same as those described above and are therefore omitted below.

[0332] In step 1902, according to an embodiment of the present invention, the terminal may receive an SSB change instruction from the base station.

[0333] In step 1903, according to an embodiment of the present invention, the terminal receives a modified SSB from a base station and can determine whether to perform radio link monitoring or beam failure detection based on the SSB. For example, the terminal may not perform radio link monitoring based on the modified SSB. Alternatively, the terminal may not apply radio link monitoring to the modified SSB while having the SSB index for the SSB index set to perform radio link monitoring. Alternatively, the terminal may perform radio link monitoring based on the modified SSB only when certain conditions are satisfied. Specific details are the same as those described above and are therefore omitted below.

[0334] In step 1904, according to an embodiment of the present invention, the terminal can perform radio link monitoring or beam failure detection with the modified SSB.

[0335] Specific details of the terminal operation according to one embodiment of the present disclosure described above may be referenced to the description of one embodiment of the present disclosure described above.

[0336] FIG. 20 is a flowchart of the operation of a base station applying an energy saving method of a wireless communication system according to one embodiment of the present disclosure.

[0337] Various modifications may be made to the method illustrated in the flowchart of FIG. 20. For example, although it is illustrated as a series of steps, the various steps in each figure may overlap, occur in parallel, occur in a different order, or occur multiple times. In other examples, steps may be omitted or replaced with other steps.

[0338] Referring to FIG. 20, in step 2001, according to an embodiment of the present invention, the base station may transmit to the terminal settings related to SSB change, radio link monitoring, or beam failure detection. The settings for SSB change may include information regarding resources for transmitting SSB, and may include a plurality of period information, etc., to change the period of the SSB. Specific details are the same as those described above and are therefore omitted below.

[0339] In step 2002, according to an embodiment of the present invention, the base station may instruct an SSB change and transmit the SSB in accordance with the instruction.

[0340] Specific details of the base station operation according to one embodiment of the present disclosure described above may be referenced to the description of one embodiment of the present disclosure described above.

[0341] The above-described flowchart illustrates an exemplary method that may be implemented in accordance with the principles of the present disclosure, and various modifications may be made to the method illustrated in the flowchart in this specification. For example, although illustrated as a series of steps, the various steps in each figure may overlap, occur in parallel, occur in a different order, or occur multiple times. In other examples, steps may be omitted or replaced with other steps.

[0342] FIG. 21 is a block diagram of a terminal according to one embodiment of the present disclosure.

[0343] Referring to FIG. 21, the terminal (2100) may include a transceiver (2101), a control unit (e.g., a processor) (2102), and a storage unit (e.g., a memory) (2103). The transceiver (2101), control unit (2102), and storage unit (2103) of the terminal (2100) may operate according to at least one or a combination thereof of the methods corresponding to the above-described embodiments. However, the components of the terminal (2100) are not limited to the illustrated examples. According to other embodiments, the terminal (2100) may include more components or fewer components than the above-described components. Furthermore, in certain cases, the transceiver (2101), control unit (2102), and storage unit (2103) may be implemented in the form of a single chip.

[0344] According to one embodiment, the transceiver (2101) may be composed of a transmitter and a receiver. The transceiver (2101) may transmit and receive signals with a base station. The signals may include control information and data. The transceiver (2101) may be configured to include an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies a received signal and down-converts the frequency. The transceiver (2101) may receive a signal through a wireless channel and output it to a control unit (2102), and transmit the signal output from the control unit (2102) through a wireless channel.

[0345] The control unit (2102) can control a series of procedures that allow the terminal (2100) to operate according to the embodiments of the present disclosure described above. For example, the control unit (2102) can perform or control the operation of the terminal to perform at least one of the methods according to the embodiments of the present disclosure or a combination thereof. The control unit (2102) may include at least one processor. For example, the control unit (2102) may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls an upper layer (e.g., an application).

[0346] The storage unit (2103) can store control information (e.g., information related to channel estimation using DMRSs transmitted from a PUSCH included in a signal obtained from a terminal (2100)) or data, and may have an area for storing data required for control of the control unit (2102) and data generated during control by the control unit (2102).

[0347] FIG. 22 is a block diagram of a base station according to one embodiment of the present disclosure.

[0348] Referring to FIG. 22, a base station (2200) may include a transceiver (2201), a control unit (e.g., a processor) (2202), and a storage unit (e.g., a memory) (2203). The transceiver (2201), control unit (2202), and storage unit (2203) of the base station (2200) may be operated according to at least one or a combination thereof of the methods corresponding to the above-described embodiments. However, the components of the base station (2200) are not limited to the illustrated examples. According to other embodiments, the base station (2200) may include more components or fewer components than the above-described components. Furthermore, in certain cases, the transceiver (2201), control unit (2202), and storage unit (2203) may be implemented in the form of a single chip.

[0349] According to one embodiment, the transceiver (2201) may be composed of a transmitter and a receiver. The transceiver (2201) may transmit and receive signals to and from a terminal. The signals may include control information and data. The transceiver (2201) may be configured to include an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies a received signal and down-converts the frequency. The transceiver (2201) may receive a signal through a wireless channel and output it to a control unit (2202), and transmit the signal output from the control unit (2202) through a wireless channel.

[0350] The control unit (2202) can control a series of procedures to enable the base station (2200) to operate according to the embodiments of the present disclosure described above. For example, the control unit (2202) can perform or control the operation of the base station to perform at least one of the methods according to the embodiments of the present disclosure or a combination thereof. The control unit (2202) may include at least one processor. For example, the control unit (2202) may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls an upper layer (e.g., an application).

[0351] The storage unit (2203) can store control information (e.g., information related to channel estimation generated using DMRSs transmitted in a PUSCH determined by the base station (2200)), data, control information received from a terminal, or data, and may have an area for storing data required for control of the control unit (2202) and data generated during control by the control unit (2202).

[0352] The drawings illustrate different examples of user devices / base stations, but various modifications to the drawings may be made. For example, a user device / base station may include any number of individual components in any suitable arrangement. In general, the drawings do not limit the scope of the disclosure to any specific configuration. Furthermore, while the drawings illustrate operating environments in which various user device / base station features disclosed in this patent document may be used, these features may be used in any other suitable system.

[0353] Although the present disclosure has been described by exemplary embodiments, various changes and modifications may be presented to those skilled in the art. The present disclosure is intended to include such changes and modifications that fall within the scope of the appended claims. The description in this application should not be interpreted as implying that any specific element, step, or function is an essential element to be included in the claims. The scope of the patented subject matter is defined by the claims.

Claims

1. A method performed by a terminal in a wireless communication system, A step of receiving an SSB setting including multiple periods for changing the SSB (synchronization signal block) from a base station; A step of receiving information from the base station instructing the SSB change, wherein the information instructing the SSB change includes a field instructing one of the plurality of periods; and A method characterized by including the step of performing radio link monitoring based on an SSB received according to the indicated period when the period indicated by the field is greater than or equal to a threshold value.

2. In Paragraph 1, A method characterized in that the above threshold value is predetermined or set by the base station.

3. In Paragraph 1, It further includes a step of performing beam failure detection based on the above SSB, A method characterized in that the above threshold value is determined based on a timer value set for beam failure detection.

4. In Paragraph 1, A method characterized in that the above SSB setting is included in an RRC (radio resource control) message.

5. In a method performed by a base station in a wireless communication system, A step of transmitting an SSB setting including multiple periods for changing the SSB (synchronization signal block) to a terminal; A step of transmitting information instructing the SSB change to the terminal, wherein the information instructing the SSB change includes a field instructing one of the plurality of periods; and It includes the step of transmitting an SSB based on a period indicated by the above field, A method characterized by performing radio link monitoring based on the SSB when the above-mentioned period is greater than or equal to a threshold value.

6. In Paragraph 5, A method characterized in that the above threshold value is predetermined or set by the base station.

7. In Paragraph 5, Beam failure detection is performed based on the above SSB, and A method characterized in that the above threshold value is determined based on a timer value set for beam failure detection.

8. In Paragraph 5, A method characterized in that the above SSB setting is included in an RRC (radio resource control) message.

9. In a terminal of a wireless communication system, At least one transceiver; At least one processor connected to the above at least one transceiver so as to be able to communicate; and The terminal is connected to communicate with at least one processor and is capable of executing individually or in any combination of the at least one processor, so that the terminal, Receive an SSB setting including multiple periods for changing the SSB (synchronization signal block) from a base station, and Information instructing the SSB change is received from the base station, and the information instructing the SSB change includes a field instructing one of the plurality of periods, and A terminal characterized by including a memory that stores a command to perform radio link monitoring based on an SSB received according to the indicated period when the period indicated by the above field is greater than or equal to a threshold value.

10. In Paragraph 9, A terminal characterized in that the above threshold value is predetermined or set by the above base station.

11. In Paragraph 9, The instruction executable by at least one processor, individually or in any combination, is such that the terminal performs beam failure detection based on the SSB, and A terminal characterized in that the above threshold value is determined based on a timer value set for beam failure detection.

12. In Paragraph 9, A terminal characterized in that the above SSB setting is included in an RRC (radio resource control) message.

13. In a base station of a wireless communication system, At least one transceiver; At least one processor connected to the above at least one transceiver so as to be able to communicate; and The base station is connected to communicate with at least one processor and is capable of executing individually or in any combination of the at least one processor, and, Transmit an SSB setting including multiple periods for changing the SSB (synchronization signal block) to the terminal, and Information instructing the SSB change is transmitted to the terminal, and the information instructing the SSB change includes a field instructing one of the plurality of periods; and It includes a memory that stores a command to transmit an SSB based on a period indicated by the above field, and A base station characterized by performing radio link monitoring based on the SSB when the above-mentioned period is greater than or equal to a threshold value.

14. In Paragraph 13, The above threshold value is predetermined or set by the base station, and A base station characterized by the above SSB setting being included in an RRC (radio resource control) message.

15. In Paragraph 13, Beam failure detection is performed based on the above SSB, and A base station characterized by the fact that the above threshold value is determined based on a timer value set for beam failure detection.

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