Method and apparatus by which user equipment having wake-up receiver transmits and receives signal in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. A user equipment (UE) according to an embodiment of the present disclosure may: receive, from a base station, configuration information about radio resource management (RRM) in a wake-up receiver; determine the length of a paging time window (PTW) on the basis of the number of discontinuous receptions (DRXs) for serving cell evaluation in the wake-up receiver; and perform, within the PTW having the determined length, RRM on a serving cell by using the wake-up receiver.

Description

Method and device for transmitting and receiving signals by a terminal having a wake-up receiver in a wireless communication system

[0001] The present disclosure relates to a wireless communication system. Specifically, the present disclosure relates to a method and device for a terminal having a wake-up receiver to perform measurements within a paging transmission window (PTW) 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 the sub-6GHz frequency band such as 3.5 gigahertz (3.5GHz), but also in the ultra-high frequency band called millimeter wave (mmWave) such as 28GHz and 39GHz ('Above 6GHz'). In addition, for 6G mobile communication technology, which is called the system after 5G communication (Beyond 5G), implementation in the terahertz band (for example, the 3 terahertz (3THz) band at 95GHz) is being considered to achieve a transmission speed that is 50 times faster than 5G mobile communication technology and an ultra-low latency time that is reduced to one-tenth.

[0003] In the early stages of 5G mobile communication technology, the goal is to support services and satisfy performance requirements for enhanced Mobile Broadband (eMBB), Ultra-Reliable Low-Latency Communications (URLLC), and massive Machine-Type Communications (mMTC). These include beamforming and massive MIMO to mitigate path loss of radio waves in ultra-high frequency bands and increase the transmission distance of radio waves, support for various numerologies (such as operation of multiple subcarrier intervals) and dynamic operation of slot formats for efficient use of ultra-high frequency resources, initial access technology to support multi-beam transmission and wideband, definition and operation of BWP (Bidth Part), new channel coding methods such as LDPC (Low Density Parity Check) codes for large-capacity data transmission and Polar Code for reliable transmission of control information, and L2 pre-processing (L2). Standardization has been made for network slicing, which provides dedicated networks specialized for specific services, and pre-processing.

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

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

[0006] Once these 5G mobile communication systems are commercialized, an explosive increase in connected devices will be connected to the communication network, necessitating enhanced functionality and performance of 5G mobile communication systems and integrated operation of these connected devices. To this end, new research will be conducted on improving 5G performance and reducing complexity, supporting AI services, supporting metaverse services, and drone communications by utilizing eXtended Reality (XR), Artificial Intelligence (AI), and Machine Learning (ML) to efficiently support Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR).

[0007] In addition, the development of these 5G mobile communication systems includes new waveforms to ensure coverage in the terahertz band of 6G mobile communication technology, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), Array Antenna, and Large Scale Antenna, metamaterial-based lenses and antennas to improve the coverage of terahertz band signals, high-dimensional spatial multiplexing technology using Orbital Angular Momentum (OAM), Reconfigurable Intelligent Surface (RIS) technology, as well as full duplex technology to improve the frequency efficiency and system network of 6G mobile communication technology, satellite, AI (Artificial Intelligence) from the design stage and AI-based communication technology that realizes system optimization by internalizing end-to-end AI support functions, and ultra-high-performance communication and computing resources to provide services with complexity that exceeds the limits of terminal computing capabilities. It can serve as a basis for the development of next-generation distributed computing technologies that can be realized by utilizing them.

[0008] As described above, as wireless communication systems develop, a method for signal transmission of terminals having wake-up receivers is required to solve the problem of excessive terminal power consumption and achieve high energy efficiency.

[0009] In order to solve the problem of excessive terminal power consumption and achieve high energy efficiency, a method for signal transmission of terminals with wake-up receivers is required.

[0010] The present disclosure relates to a 5G or 6G communication system for supporting higher data rates. According to one embodiment of the present disclosure, a UE (user equipment) receives configuration information regarding radio resource management (RRM) in a wake-up receiver from a base station, determines a length of a PTW (paging time window) based on the number of discontinuous receptions (DRXs) for serving cell evaluation in the wake-up receiver, and performs RRM for a serving cell using the wake-up receiver within the PTW of the determined length.

[0011] FIG. 1 illustrates the basic structure of a time-frequency resource domain in a wireless communication system according to one embodiment of the present disclosure.

[0012] FIG. 2 illustrates a time domain mapping structure and beam sweeping operation of a synchronization signal according to one embodiment of the present disclosure.

[0013] FIG. 3 illustrates a signal flow for random access (RA) according to one embodiment of the present disclosure.

[0014] FIG. 4 illustrates a signal flow for a terminal to report terminal capability information to a base station according to one embodiment of the present disclosure.

[0015] FIG. 5 illustrates an example of state transitions between a base station and a terminal and a state of a terminal according to a base station state according to an embodiment of the present disclosure.

[0016] FIG. 6 illustrates an example of a terminal searching for a paging message in a PTW according to one embodiment of the present disclosure when eDRX is set.

[0017] FIG. 7 is a flowchart illustrating a process in which a terminal equipped with a wake-up receiver applies enhanced PTW requirements according to an embodiment of the present disclosure when eDRX is set.

[0018] FIG. 8 is a flowchart of a method for applying an enhanced paging interruption maximum time requirement when a terminal equipped with a wake-up receiver performs cell reselection according to one embodiment of the present disclosure.

[0019] FIG. 9 is a block diagram illustrating the functional structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0020] FIG. 10 is a block diagram illustrating the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0021] The present disclosure provides a method and device for setting a paging transmission window and measuring a serving cell within the window when an eDRX of a terminal having a wake-up receiver is set in a wireless communication system.

[0022] A method performed by a UE (user equipment) in a wireless communication system according to one embodiment comprises the steps of: receiving configuration information regarding radio resource management (RRM) in a wake-up receiver from a base station; and determining the number of DRX (discontinuous reception) for serving cell evaluation in the wake-up receiver. Based on this, the step of determining the length of a PTW (paging time window) may include; and the step of performing RRM for a serving cell using a wake-up receiver within the PTW of the determined length.

[0023] In a method performed by a UE in a wireless communication system according to one embodiment, the step of performing RRM may perform RRM for at least one of a low-power synchronization signal (LP-SS), a wake-up signal, a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) included in an SS / PBCH (synchronization signal / physical broadcast channel) block.

[0024] In a method performed by a UE in a wireless communication system according to one embodiment, the step of determining the length of a PTW comprises: when a wake-up signal is detected: transmitting an uplink signal to a base station for notifying detection of a wake-up signal based on a higher layer configuration; and determining a minimum length of the PTW. Including a step of determining a minimum length of PTW greater than the DRX cycle of the dog, and if no wake-up signal is detected: Including a step of determining a DRX cycle greater than the number of DRX cycles, is the number of DRXs for serving cell evaluation on the main radio.

[0025] In a method performed by a UE in a wireless communication system according to one embodiment, the step of determining the length of a PTW comprises: determining a minimum length of the PTW; It may include a step of determining a larger than DRX cycle of the dog.

[0026] In a method performed by a UE in a wireless communication system according to one embodiment, the step of determining the length of a PTW comprises: and the number of DRXs for serving cell evaluation on the main radio. It may include a step of determining the minimum length of the PTW based on a larger value.

[0027] In a method performed by a UE in a wireless communication system according to one embodiment, the step of determining the length of a PTW comprises: The number of DRXs for serving cell evaluation on the main radio If it is larger than The method further includes a step of performing RRM for a serving cell from a preset time before the PTW, wherein the preset time is can be determined based on.

[0028] In a wireless communication system according to one embodiment, a method performed by a UE is provided, wherein, when cell reselection is determined by comparing an RRM for a serving cell with an RRM for a neighboring cell, the maximum interruption time of receiving a paging message is determined. , and Further comprising a step of determining based on

[0029] is the time required to receive a SIB (system information block),

[0030] is the time required for the main radio to switch from off to on.

[0031] is the SMTC (SSB-based measurement timing configuration) cycle of the target cell,

[0032] may represent the number of SMTC cycles required to adjust the synchronization and AGC (adaptive gain control) of the above main radio.

[0033] In a method performed by a UE in a wireless communication system according to one embodiment, is at least one of a predefined value, a value determined by the UE, and a value reported through a UE capability report.

[0034] In a wireless communication system according to one embodiment, a UE includes a transceiver including a wake-up receiver; and at least one processor communicatively coupled to the transceiver; and a memory communicatively coupled to the at least one processor and storing one or more commands, wherein the one or more commands, when individually or in combination executed by the at least one processor, cause the UE to: receive configuration information about RRM in the wake-up receiver from a base station, and the number of DRXs for serving cell evaluation in the wake-up receiver. Based on this, the length of the PTW is determined, and within the PTW of the determined length, RRM for the serving cell can be performed using the wake-up receiver.

[0035] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the attached drawings. It should be noted that, where possible, identical components are represented by identical reference numerals throughout the attached drawings. Furthermore, detailed descriptions of well-known functions and configurations that may obscure the gist of the present disclosure will be omitted.

[0036] In describing the embodiments of this disclosure, descriptions of technical details that are well known in the technical field to which this disclosure pertains and are not directly related to this disclosure will be omitted. This is to more clearly convey the gist of this disclosure without obscuring it by omitting unnecessary explanations.

[0037] For the same reason, some components in the attached drawings are exaggerated, omitted, or schematically depicted. Furthermore, the dimensions of each component do not entirely reflect its actual size. Identical or corresponding components in each drawing are assigned the same reference numbers.

[0038] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided solely to ensure that the present disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the present disclosure is defined only by the scope of the claims. Like reference numerals designate like elements throughout the specification.

[0039] At this time, it will be understood that each block of the processing flowchart drawings and combinations of the flowchart drawings can be performed by computer program instructions. These computer program instructions can be installed in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment create a means for performing the functions described in the flowchart block(s). These computer program instructions can also be stored in a computer-available or computer-readable memory that can direct a computer or other programmable data processing equipment to implement the functions in a specific manner, so that the instructions stored in the computer-available or computer-readable memory can also produce a manufactured item that includes an instruction means for performing the functions described in the flowchart block(s). Since the computer program instructions may be installed on a computer or other programmable data processing device, a series of operational steps may be performed on the computer or other programmable data processing device to create a computer-executable process, and the instructions that cause the computer or other programmable data processing device to perform the steps for performing the functions described in the flowchart block(s) may also provide steps for performing the functions described in the flowchart block(s).

[0040] Additionally, each block may represent a module, segment, or portion of code that contains one or more executable instructions for performing a specific logical function(s). It should also be noted that in some alternative implementation examples, the functions described in the blocks may occur out of order. For example, two blocks depicted in succession may actually be executed substantially concurrently, or the blocks may sometimes be executed in reverse order, depending on their respective functions.

[0041] Here, the term '~ part' used in this embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and the '~ part' performs certain roles. However, the '~ part' is not limited to software or hardware. The '~ part' may be configured to be on an addressable storage medium or may be configured to play one or more processors. Therefore, as an example, the '~ part' includes components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, 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'. Additionally, the components and '~parts' may be implemented to activate one or more CPUs within a device or secure multimedia card. In addition, in an embodiment, the '~parts' may include one or more processors.

[0042] In the following description of the present disclosure, detailed descriptions of related known functions or configurations will be omitted if they are deemed to unnecessarily obscure the gist of the present disclosure. Hereinafter, embodiments of the present disclosure will be described with reference to the attached drawings.

[0043] The terms used in the following description to identify connection nodes, terms referring to network entities, terms referring to messages, terms referring to interfaces between network entities, terms referring to various identification information, etc. are provided as examples for convenience of explanation. Therefore, the present disclosure is not limited to the terms described below, and other terms referring to objects with equivalent technical meanings may be used.

[0044] In the following description, the terms "physical channel" and "signal" may be used interchangeably with data or control signals. For example, while PDSCH (physical downlink shared channel) refers to a physical channel through which data is transmitted, PDSCH may also be used to refer to data. That is, in the present disclosure, the expression "transmitting a physical channel" may be interpreted equivalently to the expression "transmitting data or a signal through a physical channel."

[0045] Hereinafter, in the present disclosure, upper signaling refers to a signal transmission method in which a base station transmits a signal to a terminal using a downlink data channel of the physical layer, or a terminal transmits a signal to a base station using an uplink data channel of the physical layer. Upper signaling can be understood as radio resource control (RRC) signaling or a media access control (MAC) control element (CE).

[0046] Furthermore, while this disclosure describes various embodiments using terminology used in certain communication standards (e.g., 3rd Generation Partnership Project (3GPP)), these are merely illustrative examples. The various embodiments of this disclosure can be easily modified and applied to other communication systems. Furthermore, the term "terminal" can refer to not only cell phones, smartphones, IoT devices, and sensors, but also other wireless communication devices.

[0047] Hereinafter, a base station is an entity that performs resource allocation of a terminal, and may be at least one of a gNode B, a gNB, an eNode B, an eNB, a Node B, a BS (Base Station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (user equipment), an MS (mobile station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. Of course, the present invention is not limited to the above examples. In addition, although various embodiments of the present invention are described below using a system based on LTE, LTE-A, or NR as an example, various embodiments of the present invention may be applied to other communication systems having a similar technical background or channel type. In addition, various embodiments of the present invention may be applied to other communication systems through some modifications without significantly departing from the scope thereof at the discretion of a person having skilled technical knowledge.

[0048] To handle the explosive growth in mobile data traffic, the initial standards for the 5G (5th generation) system, or NR (new radio access technology), the next-generation communication system following LTE (long term evolution or E-UTRA (evolved universal terrestrial radio access)) and LTE-A (LTE-advanced or E-UTRA Evolution), have been completed. While existing mobile communication systems have focused on conventional voice / data communications, the 5G system aims to satisfy various services and requirements, such as enhanced Mobile BroadBand (eMBB) services to improve existing voice / data communications, ultra-reliable and low latency communication (URLLC) services, and massive machine type communication (MTC) services that support large-scale machine-type communication.

[0049] While the transmission bandwidth of existing LTE and LTE-A systems per single carrier is limited to a maximum of 20 MHz, the 5G system aims to utilize a much wider ultra-wide bandwidth to provide ultra-high-speed data services of up to several Gbps. Accordingly, the 5G system is considering ultra-high frequency bands ranging from several GHz up to 100 GHz as candidate frequencies, where securing ultra-wide bandwidth frequencies is relatively easy. Additionally, wide bandwidth frequencies for the 5G system can be secured through frequency reallocation or allocation within frequency bands ranging from several hundred MHz to several GHz used in existing mobile communication systems.

[0050] Ultra-high frequency radio waves, sometimes called millimeter waves (mmWave), have wavelengths on the order of millimeters. However, in ultra-high frequency bands, path loss increases proportionally to the frequency band, reducing the coverage of mobile communication systems.

[0051] To overcome the drawback of reduced coverage in ultra-high frequency bands, beamforming technology is applied, which uses multiple antennas to focus radio wave energy toward a predetermined target point and thereby increase the transmission range. In other words, a signal using beamforming technology has a relatively narrow beam width, and the radiation energy is concentrated within this narrowed beam width, increasing the transmission range. Beamforming technology can be applied to both the transmitter and receiver. In addition to increasing coverage, beamforming technology also reduces interference in areas outside the beamforming direction. For beamforming technology to function properly, accurate measurement and feedback methods for the transmission and reception beams are required. Beamforming technology can be applied to control channels or data channels that correspond one-to-one between a given terminal and a base station. Furthermore, beamforming can also be applied to common signals transmitted by a base station to multiple terminals within a system, such as synchronization signals, physical broadcast channels (PBCHs), and control and data channels for transmitting system information, to increase coverage. When applying beamforming technology to a common signal, beam sweeping technology, which transmits a signal by changing the beam direction, is additionally applied so that the common signal can reach terminals located at any location within the cell.

[0052] Another requirement for 5G systems is ultra-low latency services, with transmission delays of approximately 1ms between transmitters and receivers. One way to reduce transmission delay is to design a frame structure based on a short transmission time interval (TTI) compared to LTE and LTE-A. A TTI is the basic unit of time for scheduling, and the TTI of existing LTE and LTE-A systems is 1ms, which corresponds to the length of one subframe. For example, to meet the ultra-low latency requirements of 5G systems, possible short TTIs include 0.5ms, 0.25ms, and 0.125ms, which are shorter than those of existing LTE and LTE-A systems.

[0053] FIG. 1 illustrates the basic structure of a time-frequency resource domain in a wireless communication system according to one embodiment of the present disclosure. Specifically, FIG. 1 is a diagram illustrating the basic structure of a time-frequency resource domain, which is a wireless resource domain in which data or control channels of a 5G system are transmitted.

[0054] Referring to Figure 1, the horizontal axis in Figure 1 represents the time domain and the vertical axis represents the frequency domain. The minimum transmission unit in the time domain of a wireless communication system is an OFDM (orthogonal frequency division multiplexing) symbol. The dog symbols (102) come together to form one slot (106), A plurality of slots can be combined to form a subframe (105). The length of the subframe is 1.0 ms, and 10 subframes can be combined to form a 10 ms frame (114). The minimum transmission unit in the frequency domain is a subcarrier, and the bandwidth of the entire system transmission bandwidth is a total of N BW It can be composed of (104) subcarriers.

[0055] The basic unit of resources in the time-frequency domain is a resource element (RE) (112), which can be represented by an OFDM symbol index and a subcarrier index. A resource block (RB or physical resource block, PRB) is a resource block in the frequency domain. can be defined as a series of consecutive subcarriers (110). In the 5G system =12, and the data rate can increase in proportion to the number of RBs scheduled to the terminal.

[0056] In wireless communication systems, a base station can map data in RB units and perform scheduling on RBs, which typically constitute a slot for a given terminal. That is, in a 5G system, the basic time unit for scheduling may be a slot, and the basic frequency unit for scheduling may be an RB.

[0057] Number of OFDM symbols It is determined by the length of the cyclic prefix (CP) added to each symbol to prevent interference between symbols. For example, if the normal CP is applied, =14, when Extended CP is applied =12. Extended CP is applied to systems with relatively long transmission distances compared to regular CP, allowing for maintaining orthogonality between symbols. In the case of regular CP, the ratio of CP length to symbol length is maintained at a constant value, so the overhead due to CP can be maintained constant regardless of the subcarrier spacing. That is, if the subcarrier spacing is small, the symbol length becomes longer, and thus the CP length can also become longer. Conversely, if the subcarrier spacing is large, the symbol length becomes shorter, and thus the CP length can be reduced. The symbol length and CP length can be inversely proportional to the subcarrier spacing.

[0058] In wireless communication systems, various frame structures can be supported by adjusting the subcarrier spacing to satisfy various services and requirements. For example, from the perspective of operating frequency band, a larger subcarrier spacing is advantageous for recovering phase noise in high-frequency bands. From the perspective of transmission time, a larger subcarrier spacing shortens the symbol length in the time domain, which in turn shortens the slot length, making it advantageous for supporting ultra-low-latency services such as URLLC. From the perspective of cell size, a longer CP length allows for larger cells, so a smaller subcarrier spacing allows for relatively larger cells. In mobile communications, a cell is a concept referring to the area covered by a single base station.

[0059] Subcarrier spacing, CP length, etc. are essential information for OFDM transmission and reception. For smooth transmission and reception, the base station and terminal must recognize the subcarrier spacing, CP length, etc. as common values.

[0060] [Table 1] below shows the relationship between the subcarrier spacing configuration (μ), subcarrier spacing (f), and CP length supported in the 5G system.

[0061] [Table 1]

[0062]

[0063] [Table 2] below shows the number of symbols per slot for each subcarrier spacing setting (μ) for the general CP. ), number of slots per frame ( ), number of slots per subframe ( ) is indicated.

[0064] [Table 2]

[0065]

[0066] [Table 3] below shows the number of symbols per slot (μ) for each subcarrier spacing setting for extended CP. ), number of slots per frame ( ), number of slots per subframe ( ) is indicated.

[0067] [Table 3]

[0068]

[0069] In the early stages of 5G system deployment, coexistence or dual-mode operation with existing LTE and / or LTE-A (hereinafter referred to as LTE / LTE-A) systems was anticipated. This would allow existing LTE / LTE-A systems to provide stable system operation to terminals, while the 5G system would provide enhanced services to terminals. Therefore, the 5G system's frame structure must at least include the LTE / LTE-A frame structure or essential parameter set (e.g., subcarrier spacing = 15 kHz).

[0070] For example, comparing a frame structure with a subcarrier spacing setting μ=0 (hereinafter referred to as frame structure A) and a frame structure with a subcarrier spacing setting μ=1 (hereinafter referred to as frame structure B), compared to frame structure A, frame structure B shows that the subcarrier spacing and RB size are twice as large, and the slot length and symbol length are twice as small. In the case of frame structure B, two slots can constitute one subframe, and 20 subframes can constitute one frame.

[0071] Generalizing the frame structure of a 5G system provides high scalability by ensuring that essential parameters—subcarrier spacing, CP length, and slot length—have integer multiple relationships for each frame structure. A fixed-length subframe of 1 ms can be defined to represent a reference time unit independent of the frame structure.

[0072] The frame structure can be applied to various scenarios. From the perspective of cell size, the longer the CP length, the larger the cell can be supported, so frame structure A can support relatively larger cells than frame structure B. From the perspective of operating frequency band, the larger the subcarrier spacing, the more advantageous it is for recovering phase noise in the high-frequency band, so frame structure B can support relatively higher operating frequencies than frame structure A. From the perspective of service, the shorter the slot length, which is the basic time unit of scheduling, the more advantageous it is for supporting ultra-low-latency services such as URLLC, so frame structure B can be relatively more suitable for URLLC services than frame structure A.

[0073] In the following description of the present disclosure, uplink (UL) may refer to a wireless link through which a terminal transmits data or a control signal to a base station, and downlink (DL) may refer to a wireless link through which a base station transmits data or a control signal to a terminal.

[0074] In the initial access stage where a terminal first accesses the system, the terminal can synchronize downlink time and frequency from a synchronization signal transmitted by a base station through cell search, and obtain a cell identifier (cell ID). The terminal can receive a physical broadcast channel (PBCH) using the obtained cell ID, and obtain a master information block (MIB), which is essential system information, from the PBCH. Additionally, the terminal can obtain cell-common transmission and reception-related control information by receiving system information (system information block, SIB) transmitted by the base station. The cell-common transmission and reception-related control information may include random access (RA)-related control information, paging-related control information, and common control information for various physical channels.

[0075] The synchronization signal serves as a reference for cell search, and the subcarrier spacing can be applied to suit channel conditions such as phase noise for each frequency band. In the case of data channels or control channels, the subcarrier spacing can be adaptively applied depending on the service type to support various services as described above.

[0076] FIG. 2 illustrates a time domain mapping structure and beam sweeping operation of a synchronization signal according to one embodiment of the present disclosure.

[0077] Hereinafter, the following components may be predefined for the purpose of explaining the present disclosure.

[0078] - PSS (primary synchronization signal): A signal that serves as the basis for DL ​​time / frequency synchronization and can provide some cell ID information.

[0079] - SSS (secondary synchronization signal): It serves as a reference for DL ​​time / frequency synchronization and can provide some remaining information, including the cell ID. Additionally, it can serve as a reference signal (RS) for PBCH demodulation.

[0080] - PBCH (physical broadcast channel): It can provide MIB (master information block), which is essential system information required for transmission and reception of data channels and control channels of the terminal. Essential system information can include control information related to the search space indicating radio resource mapping information of the control channel, scheduling control information for a separate data channel that transmits system information, and SFN (system frame number), which is a frame-unit index that serves as a timing reference.

[0081] - SS / PBCH block (synchronization signal / PBCH block or SSB): An SS / PBCH block can be composed of N OFDM symbols and can include a combination of PSS, SSS, PBCH, etc. In a system where beam sweeping technology is applied, an SS / PBCH block can be the minimum unit to which beam sweeping is applied. In a 5G system, N can be 4. The base station can transmit up to L SS / PBCH blocks, and the L SS / PBCH blocks can be mapped within a half frame (0.5 ms). The L SS / PBCH blocks can be periodically repeated in units of a predetermined period P. The period P can be notified to the terminal by signaling from the base station. If there is no separate signaling for the period P, the terminal can apply a pre-agreed default value.

[0082] FIG. 2 illustrates an example in which beam sweeping is applied to SS / PBCH block units over time. In the example of FIG. 2, terminal 1 (205) can receive an SS / PBCH block using a beam radiated in the direction of #d0 (203) by beamforming applied to SS / PBCH block #0 at time t1 (201). Terminal 2 (206) can receive an SS / PBCH block using a beam radiated in the direction of #d4 (204) by beamforming applied to SS / PBCH block #4 at time t2 (202). 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, terminal 1 (205) may have difficulty in obtaining time / frequency synchronization and essential system information from an SS / PBCH block through a beam radiated in the direction of #d4 (204) which is far from the location of terminal 1 (205).

[0083] In addition to the initial connection procedure, the terminal may receive SS / PBCH blocks to determine whether the radio link quality of the current cell is maintained at a certain level. Furthermore, during a handover procedure, in which the terminal moves from the current cell to a neighboring cell, the terminal may receive SS / PBCH blocks from the neighboring cell to determine the radio link quality of the neighboring cell and obtain time / frequency synchronization with the neighboring cell.

[0084] After the terminal acquires MIB and system information from the base station through the initial access procedure, the terminal can perform a random access procedure to transition the link with the base station to the connected state (or RRC_CONNECTED state). Upon completion of the random access procedure, the terminal transitions to the connected state (or RRC_CONNECTED state), enabling one-to-one communication between the base station and the terminal. The random access procedure is described in detail below with reference to FIG. 3.

[0085] Figure 3 illustrates the flow of signals for random access (RA).

[0086] Referring to FIG. 3, in step 310, a terminal may transmit a random access preamble to a base station. The random access preamble, which is the first transmission message of the terminal in the random access procedure, may be referred to as message 1. The base station may measure a transmission delay value between the terminal and the base station from the random access preamble and synchronize uplink. At this time, the terminal may arbitrarily select which random access preamble to use within a random access preamble set given in advance by system information. The initial transmission power of the random access preamble may be determined according to the path loss measured by the terminal between the base station and the terminal. In addition, the terminal may determine the transmission beam direction of the random access preamble from the synchronization signal received from the base station and transmit the random access preamble.

[0087] In step 320, the base station may transmit a random access response (RAR) (or message 2) for the random access preamble received in step 310. The base station may transmit an uplink transmission timing adjustment command to the terminal based on a transmission delay value measured from the random access preamble. The base station may transmit to the terminal uplink resources to be used and a power control command as scheduling information. The scheduling information transmitted by the base station may include control information for the uplink transmission beam of the terminal.

[0088] If the terminal does not receive the random access response (RAR) (or message 2), which is scheduling information for message 3, from the base station within a predetermined time in step 320, step 310 may be performed again. If step 310 is performed again, the terminal may increase the probability of the base station receiving the random access preamble by transmitting the random access preamble with a transmission power increased by a predetermined step (e.g., power ramping).

[0089] In step 330, the terminal can transmit uplink data including its terminal ID (i.e., message 3) to the base station using the uplink resources allocated in step 320. The terminal can transmit the uplink data including the terminal ID to the base station through an uplink data channel (physical uplink shared channel, PUSCH). The transmission timing of the uplink data channel for transmitting Message 3 may follow the timing control command received from the base station in step 320. The transmission power of the uplink data channel for transmitting Message 3 may be determined by considering the power control command received from the base station in step 320 and the power ramping value of the random access preamble. The uplink data channel for transmitting Message 3 may mean the first uplink data signal that the terminal transmits to the base station after transmitting the random access preamble.

[0090] In step 340, if the base station determines that the terminal has performed random access without collision with other terminals, it can transmit data (i.e., message 4) including the ID of the terminal that transmitted uplink data in step 330 to the terminal. If the terminal receives the signal transmitted by the base station in step 340 from the base station, it can determine that the random access has been successful. The terminal can transmit HARQ-ACK (hybrid automatic repeat request acknowledgment) information indicating whether message 4 was successfully received to the base station through the uplink control channel (physical uplink control channel, PUCCH).

[0091] If the data transmitted by the terminal in step 330 collides with data from another terminal, causing the base station to fail to receive a data signal from the terminal, the base station may not transmit any more data to the terminal. If the terminal fails to receive the data transmitted from the base station in step 340 within a certain period of time, it may determine that the random access procedure has failed and may proceed again from step 310.

[0092] When a terminal successfully completes a random access procedure, the terminal transitions to a connected state (or RRC_CONNECTED state), and one-to-one communication can be enabled between the base station and the terminal. The base station can receive terminal capability (UE capability) information from the terminal in the connected state (or RRC_CONNECTED state) and adjust scheduling by referring to the terminal capability (UE capability) information of the corresponding terminal. Through the terminal capability (UE capability) information, the terminal can inform the base station whether it supports a certain function, the maximum allowable value of the function supported by the terminal, etc. Therefore, the terminal capability (UE capability) information reported by each terminal to the base station can have different values ​​for each terminal.

[0093] For example, a terminal may report terminal capability information including at least one of the following control information to a base station.

[0094] - Control information related to frequency bands supported by the terminal

[0095] - Control information related to channel bandwidth supported by the terminal

[0096] - Control information related to the maximum modulation method supported by the terminal

[0097] - Control information related to the maximum number of beams supported by the terminal

[0098] - Control information related to the maximum number of layers supported by the terminal

[0099] - Control information related to CSI reporting supported by the terminal

[0100] - Control information on whether the terminal supports frequency hopping

[0101] - Bandwidth-related control information when supporting carrier aggregation (CA)

[0102] - Control information on whether cross carrier scheduling is supported when carrier aggregation is supported.

[0103] Figure 4 illustrates the flow of signals for a terminal to report terminal capability information to a base station.

[0104] Referring to FIG. 4, at step 410, the base station (402) may transmit a UE capability information request message to the terminal (401). Based on the UE capability information request from the base station (402), the terminal (401) may transmit UE capability information to the base station at step 420. According to one embodiment, the terminal (401) may transmit UE capability information to the base station (402) regardless of the UE capability information request from the base station (402).

[0105] 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. Conversely, a terminal that is not connected can be in the RRC_IDLE state, and a terminal in the RRC_IDLE state can perform the following processes.

[0106] - Performs terminal-specific DRX (discontinuous reception) cycles set by the upper layer.

[0107] - Receive paging messages from the core network

[0108] - Obtain system information

[0109] - Measurement actions related to serving cells (or camping cells) and cell selection / reselection

[0110] - Measurement operations related to surrounding cells and cell reselection

[0111] In more detail with respect to the measurement operation and cell selection / reselection related to the serving cell (or the cell on which the UE is camping) (referred to as MR (main radio) RRM (radio resource management) measurement / evaluation in this disclosure), the UE can measure the SS-RSRP (synchronization signal - reference signal received power) and SS-RSRQ (synchronization signal - reference signal received quality) levels for the serving cell (or the cell on which the UE is camping) at least every M1*N1 DRX cycle, and evaluate the cell selection decision criterion S based on the measured values. Here, when the SMTC (SSB-based measurement timing configuration) period is greater than 20ms and the DRX cycle is less than or equal to 0.64s, M1=2, and in other cases, M1=1.

[0112] N1 can be determined by the following table.

[0113] [Table 4]

[0114]

[0115] The cell selection criterion S corresponds to SS-RSRP rxlev > 0 and S corresponding to SS-RSRQ qual > 0 can be satisfied.

[0116] S rxlev = Q rxlevmeas - (Q rxlevmin+ Q rxlevminoffset )- P compensation - Q offsettemp

[0117] S qual = Q qualmeas - (Q qualmin + Q qualminoffset ) - Q offsettemp

[0118] Here, Q rxlevmeas is the measured SS-RSRP, and Q qualmeas is the measured SS-RSRQ, and Q rxlevmin is the minimum required reception signal level in the serving cell and can be received by the terminal as system information, and Q qualmin is the quality level of the received signal required at the minimum limit in the serving cell and can be received by the terminal as system information. The remaining parameters are presented in 3GPP TS 38.304. The terminal can determine the SS-RSRP of the serving cell by filtering from at least two measurement values ​​that are spaced apart by at least half a DRX cycle in determining the measured SS-RSRP. In addition, the terminal can determine the SS-RSRQ of the serving cell by filtering from at least two measurement values ​​that are spaced apart by at least half a DRX cycle in determining the measured SS-RSRQ.

[0119] More specifically, regarding the measurement behavior and cell reselection related to surrounding cells, the terminal is N serv If the UE determines that the serving cell does not satisfy the cell selection criterion S during consecutive DRX cycles, the UE may initiate measurements of all surrounding cells other than the serving cell. If the UE fails to find a new suitable cell for 10 s, the UE may initiate a cell selection procedure for the selected public land mobile network (PLMN).

[0120] The terminal starts measuring the surrounding cells every T measureMeasure the SS-RSRP and SS-RSRQ levels every T and the surrounding cells evaluate It can be evaluated whether the cell reselection criteria are satisfied within the terminal. When the terminal detects a new cell, the terminal can detect the newly detected cell after T detect It can be evaluated whether the cell reselection criteria are satisfied. T reselection During the cell reselection, if a neighboring cell or a newly detected cell is better than the serving cell based on the cell reselection judgment criteria, and at the same time, if more than 1 second has passed since the terminal camped on the current serving cell, the terminal may reselect the neighboring cell or the newly detected cell as the new serving cell. Here, the T measure , T evaluate , T reselection Parameters such as may be determined in the specification according to the DRX cycle or may be set by upper layer signals. The terminal may determine the measured SS-RSRP by at least T in the time domain. measure The SS-RSRP of a neighboring cell can be determined by filtering at least two SS-RSRP or SS-RSRQ measurements that are half a distance apart.

[0121] The above cell reselection judgment criteria are calculated by the following parameters: R per cell s , R n The cell selection order can be determined based on R per cell. s , R n You can determine the cell ranking in order of highest value among them.

[0122] R s = Q meas,s + Q hyst - Qoffset temp

[0123] R n = Q meas,n - Qoffset - Qoffset temp

[0124] Here, Q meas,s , Q meas,nrepresents the RSRP measurement values ​​of the serving cell and surrounding cells, respectively, and Q hyst , Qoffset, Qoffset temp The back can be set by a higher signal.

[0125] With regard to the measurement of surrounding cells, the measurement of surrounding cells is stopped when a certain condition is satisfied or the above T measure It is possible to perform neighboring cell measurements by a longer period. In one embodiment, if the terminal is moving slowly or stopped within the cell, or if it is determined that the terminal is not at the cell edge, the terminal may perform T measure You can measure surrounding cells at longer intervals by multiplying the scaling factor, or stop measuring surrounding cells for up to 1 hour.

[0126] In 5G systems, a new terminal state called RRC_INACTIVE has been defined to reduce the energy and time consumed during initial access. In addition to the actions performed by RRC_IDLE terminals, RRC_INACTIVE terminals can perform the following processes:

[0127] - Storage of AS (access stratum) information required for cell access

[0128] - Terminal-specific DRX cycle operation set by the RRC layer

[0129] - Setting up and periodically updating RNA (RAN (radio access network)-based notification area) that can be utilized during handover by the RRC layer

[0130] - Monitoring of RAN-based paging messages transmitted via I-RNTI (inactive-radio network temporary identifier)

[0131] A terminal in RRC_CONNECTED state can change from RRC_CONNECTED to RRC_INACTIVE or RRC_IDLE state by receiving an RRC Release instruction from the base station.

[0132] A terminal in RRC_INACITVE or RRC_IDLE state can change from RRC_INACTIVE or RRC_IDLE to RRC_CONNECTED state by performing random access and completing all random access procedures.

[0133] Below, a scheduling method for a base station to transmit downlink data to a terminal or instruct the terminal to transmit uplink data is described.

[0134] Downlink control information (DCI) may be control information transmitted from a base station to a terminal via the downlink. Downlink control information may include downlink data scheduling information or uplink data scheduling information for a given terminal. Typically, the base station independently performs channel coding on DCI for each terminal and then transmits it to each terminal via a physical downlink control channel (PDCCH).

[0135] The base station can operate by applying a DCI format determined for the purpose of scheduling, such as whether it is scheduling information for downlink data (downlink assignment), scheduling information for uplink data (uplink grant), or DCI for power control.

[0136] A base station can transmit downlink data to a terminal via the physical downlink shared channel (PDSCH), a physical channel for downlink data transmission. The base station can inform the terminal of scheduling information, such as the specific mapping location in the time and frequency domains of the PDSCH, modulation scheme, HARQ-related control information, and power control information, through DCI related to downlink data scheduling information among the DCIs transmitted via the PDCCH.

[0137] A terminal can transmit uplink data to a base station via the physical uplink shared channel (PUSCH), a physical channel for uplink data transmission. The base station can inform the terminal of scheduling information, such as the specific mapping location in the time and frequency domains of the PUSCH, modulation method, HARQ-related control information, and power control information, through DCI related to uplink data scheduling information among the DCI transmitted via the PDCCH.

[0138] The time-frequency resources to which the PDCCH is mapped may be referred to as a control resource set (CORESET). A CORESET may be configured for all or part of the frequency resources of the bandwidth supported by the terminal in the frequency domain. In the time domain, it may be configured with one or more OFDM symbols, which may be defined as the CORESET length (control resource set duration). The base station may configure one or more CORESETs to the terminal through higher layer signaling (e.g., system information, master information block (MIB), radio resource control (RRC) signaling). When the base station configures a CORESET to the terminal, this may mean that the base station provides the terminal with information such as a CORESET identifier, the frequency location of the CORESET, and the symbol length of the CORESET. The information that the base station provides to the terminal to configure the CORESET may include at least some of the information included in [Table 5] below.

[0139] [Table 5]

[0140]

[0141] CORESET is in the frequency domain It can be composed of RBs and in the time domain It can be composed of {1, 2, 3} symbols. The NR PDCCH can be composed of one or more control channel elements (CCEs). One CCE can be composed of six resource element groups (REGs), and a REG can be defined as one RB during one OFDM symbol. Within one CORESET, REGs can be indexed in time-first order, starting with REG index 0 from the first OFDM symbol of the CORESET, the lowest RB.

[0142] Interleaved and non-interleaved transmission methods for PDCCH can be supported. The base station can configure whether to use interleaved or non-interleaved transmission for each CORESET to the terminal through upper layer signaling. Interleaving can be performed on a per REG bundle basis. A REG bundle can be defined as a set of one or more REGs. The terminal can determine the CCE-to-REG mapping method for the corresponding CORESET based on whether to use interleaved or non-interleaved transmission as configured by the base station, as shown in [Table 6] below.

[0143] [Table 6]

[0144]

[0145] The base station can provide the terminal with configuration information, such as information about the symbol to which the PDCCH is mapped within the slot and the transmission period, through signaling.

[0146] The search space of the PDCCH is described as follows. The number of CCEs required to transmit the PDCCH can be 1, 2, 4, 8, or 16 depending on the aggregation level (AL), and different numbers of CCEs can be used for link adaptation of the downlink control channel. For example, when AL=L, a single downlink control channel can be transmitted through L CCEs. The UE performs blind decoding, which detects a signal without knowing information about the downlink control channel. For this purpose, a search space representing a set of CCEs can be defined. The search space is a set of downlink control channel candidates consisting of CCEs that the UE should attempt to decode at a given aggregation level. Since there are various aggregation levels that create a single group with 1, 2, 4, 8, or 16 CCEs, the UE can have multiple search spaces. A search space set can be defined as the set of search spaces at all established aggregation levels.

[0147] Search spaces can be classified into a common search space (CSS) and a UE-specific search space (USS). A certain group of UEs, or all UEs, can scan the common search space of the PDCCH to receive cell-common control information, such as dynamic scheduling for system information blocks (SIBs) or paging messages. For example, a UE can receive scheduling allocation information for a PDSCH for system information reception by scanning the common search space of the PDCCH. In the case of the common search space, since a certain group of UEs, or all UEs, must receive the PDCCH, it can be defined as a set of pre-arranged CCEs. UE-specific scheduling allocation information for a PDSCH or PUSCH can be received by scanning the UE-specific search space of the PDCCH. The UE-specific search space can be defined UE-specifically as a function of the UE ID and various system parameters.

[0148] The base station can configure the search space configuration information of the PDCCH to the terminal through higher layer signaling (e.g., SIB, MIB, RRC signaling). For example, the base station can configure the number of PDCCH candidates at each aggregation level L, the monitoring period for the search space, the monitoring occasion for each symbol within the slot for the search space, the search space type (common search space or terminal-specific search space), the combination of DCI format and RNTI to be monitored in the corresponding search space, the CORESET index to be monitored for the search space, etc. to the terminal. For example, the parameters for the search space for the PDCCH may include information such as the information in [Table 7] below.

[0149] [Table 7]

[0150]

[0151] Based on the configuration information transmitted to the terminal, the base station may configure one or more search space sets for the terminal. According to one embodiment, the base station may configure search space set 1 and search space set 2 for the terminal. In search space set 1, the terminal may be configured to monitor DCI format A scrambled with X-RNTI in a common search space, and in search space set 2, the terminal may be configured to monitor DCI format B scrambled with Y-RNTI in a terminal-specific search space.

[0152] According to the configuration information transmitted by the base station, one or more search space sets may exist in the common search space or the terminal-specific search space. For example, search space set #1 and search space set #2 may be configured as the common search space, and search space set #3 and search space set #4 may be configured as the terminal-specific search space.

[0153] In a common search space, a terminal may monitor the following combinations of DCI formats and RNTIs. Various embodiments of the present disclosure, of course, are not limited to the examples below.

[0154] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI, SI-RNTI

[0155] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0156] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0157] - DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0158] - DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0159] In a terminal-specific search space, a terminal may monitor the following combinations of DCI formats and RNTIs. Various embodiments of the present disclosure, of course, are not limited to the examples below.

[0160] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0161] - DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0162] RNTIs may follow the following definitions and uses. According to various embodiments of the present disclosure, of course, they are not limited to the examples below.

[0163] - C-RNTI (cell RNTI): For terminal-specific PDSCH or PUSCH scheduling purposes.

[0164] - TC-RNTI (temporary Cell RNTI): For terminal-specific PDSCH scheduling purposes

[0165] - CS-RNTI (configured scheduling RNTI): Used for terminal-specific PDSCH scheduling that is set semi-statically.

[0166] - RA-RNTI (random access RNTI): Used for PDSCH scheduling in the random access phase.

[0167] - P-RNTI (paging RNTI): Used for scheduling PDSCH where paging is transmitted.

[0168] - SI-RNTI (system information RNTI): Used for scheduling PDSCH where system information is transmitted.

[0169] - INT-RNTI (interruption RNTI): Used to indicate whether puncturing is performed on the PDSCH.

[0170] - TPC-PUSCH-RNTI (transmit power control for PUSCH RNTI): Used to indicate power control commands for PUSCH.

[0171] - TPC-PUCCH-RNTI (transmit power control for PUCCH RNTI): Used to indicate power control commands for PUCCH.

[0172] - TPC-SRS-RNTI (transmit power control for SRS RNTI): Used to indicate power control commands for SRS.

[0173] The DCI formats described above can follow the definitions shown in [Table 8] below.

[0174] [Table 8]

[0175]

[0176] [Mathematical Formula 1]

[0177]

[0178] - L: Integration level

[0179] - n CI : Carrier Index

[0180] - N CCE,p : Total number of CCEs existing within the control resource set p

[0181] - n μ s,f : slot index

[0182] - M (L) p,s,max : Number of PDCCH candidates for aggregation level L

[0183] - m snCI = 0, ..., M (L) p,s,max-1: PDCCH candidate index of aggregation level L

[0184] - i = 0, ..., L-1

[0185] - = , , =39827, , ,

[0186] - n RNTI : Terminal identifier

[0187] The value can be 0 for a common search space.

[0188] In the case of a terminal-specific search space, the value may correspond to a value that changes according to the terminal's ID (C-RNTI or ID set to the terminal by the base station) and time index.

[0189] As described above, to achieve ultra-high-speed data services reaching several Gbps in 5G systems, ultra-wide bandwidth signal transmission and reception of tens to hundreds of MHz or even several GHz may be supported. Ultra-wide bandwidth signal transmission and reception may be supported through a single component carrier (CC) or through carrier aggregation (CA) technology that combines multiple component carriers. When a mobile communication service provider cannot secure a frequency with sufficient bandwidth for ultra-high-speed data services through a single component carrier, carrier aggregation technology can increase the total frequency bandwidth by combining individual component carriers with relatively small bandwidths, thereby enabling ultra-high-speed data services.

[0190] 5G systems are designed and developed to address a wide range of use cases. In addition to standby time, reliability, and availability, device energy efficiency is crucial in 5G systems. 5G devices typically consume tens of milliwatts (mW) in RRC_IDLE / RRC_INACTIVE states and hundreds of mW in RRC_CONNECTED states, requiring weekly or daily charging depending on individual usage. Designing for extended battery life can be essential not only for a better user experience but also for improving energy efficiency. Energy efficiency can be even more critical for devices without a continuous power source (e.g., devices using small rechargeable or single coin-cell batteries). Sensors and actuators are widely deployed in 5G use cases for monitoring, measurement, and charging. Typically, these devices require batteries that are non-rechargeable and can last for at least several years. Wearables, including smartwatches, rings, eHealth devices, and medical monitoring devices, typically struggle to last more than one to two weeks, depending on usage.

[0191] In one embodiment, the power consumption of a 5G terminal depends on the set length of wake-up periods (e.g., paging cycles), and a large extended discontinuous reception (eDRX) cycle may be used to meet battery life requirements. However, the eDRX approach relies on high latency to maintain long battery life, making it unsuitable for low-latency services. For example, in a fire detection and extinguishing use case, fire shutters may need to be closed and sprinklers turned on by actuators within 1-2 seconds of a fire being detected by a sensor. In this case, latency may be critical, and a long eDRX cycle, as in the past, is not suitable because it cannot meet the latency requirements.

[0192] By providing a method and device for setting a paging transmission window and measuring cell signal quality within the window in an eDRX setting situation of a terminal having a wake-up receiver in the present disclosure, it is possible to align different paging message transmission and reception understanding between a network and a terminal.

[0193] [Example 1: LP-WUS / WUR Description]

[0194] As mentioned above, existing terminals are not suitable for simultaneously satisfying both high energy efficiency and low latency requirements. Therefore, the introduction of a low-power wake-up receiver (LP-WUR), a separate receiver that reduces power consumption and latency when there is no traffic, is being discussed. Below, a terminal that includes a wake-up receiver is described in detail.

[0195] FIG. 5 illustrates an example of state transitions between a base station and a terminal, and a state of a terminal depending on the base station state, according to an embodiment of the present disclosure. Specifically, FIG. 5 illustrates state transitions between a base station and a terminal to address the aforementioned issues.

[0196] In one embodiment, a 5G terminal may require one wake-up per DRX cycle, and when the terminal wakes up once per eDRX cycle, the power consumption resulting from this may account for most of the terminal power consumption during periods without signaling or data traffic. Therefore, if the terminal can wake up only when triggered, such as by paging, the power consumption of the terminal can be drastically reduced. According to one embodiment of the present disclosure, a method for reducing power consumption may be achieved by triggering a main radio (main radio or main receiver, for example, a legacy NR radio) using a low-power wake-up signal (LP-WUS), as shown in FIG. 5. Specifically, the method may include turning on the main radio only when data transmission and reception are required, using a wake-up receiver (WUR or LR (LP-WUR, Low Power Wake-Up Receiver), which is a separate receiver capable of monitoring the wake-up signal at ultra-low power. In the present disclosure, the main radio (504) may mean a receiver that receives the main radio, and the wake-up receiver (502) may mean a receiver that receives a wake-up signal.

[0197] According to one embodiment of the present disclosure, in step 501, the base station may transmit a wake-up signal (WUS) to the terminal.

[0198] At step 502, the terminal can receive a wake-up signal using a wake-up receiver.

[0199] At step 503, the terminal can trigger the main radio to turn on (turn on) if it is in an off state based on the received signal.

[0200] In step 504, the terminal may set its main radio to awake. If there is no data traffic from the base station to transmit to the terminal and the conditions for the terminal to monitor a wake-up signal are met, the terminal may keep its main radio turned off and enter a sleep state. In one embodiment, the terminal may be set to a deep sleep (DS) or ultra-deep sleep (UDS) state rather than completely turned off. A terminal in a UDS state may consume less power than a terminal in a DS state.

[0201] In step 505, when data traffic to be transmitted from the base station to the terminal occurs and the terminal detects a wake-up signal transmitted by the base station in step 501, the main radio can be turned on in step 504, and in step 506, the terminal can receive the data transmitted by the base station through the main radio rather than the wake-up receiver.

[0202] In one embodiment, the power consumption for monitoring a wake-up signal depends on the wake-up signal design, the hardware module of the wake-up receiver used for signal detection and processing, so that the power consumption savings can be maximized for power-sensitive and small form factor devices including IoT use cases (such as industrial sensors and controllers) and wearable devices.

[0203] In one embodiment, a terminal including a wake-up receiver may report to a base station that it has the capability to wake up the main radio using the wake-up receiver or may report capability information indicating that the terminal includes a wake-up receiver to the base station. According to one embodiment of the present disclosure, the capability of the terminal to wake up the main radio using the wake-up receiver or the capability of the terminal including the wake-up receiver may be included in terminal capability information.

[0204] According to one embodiment, a terminal may report capability information about a wake-up receiver to a base station through the terminal capability information reporting procedure of FIG. 4.

[0205] In one embodiment, when a base station supports a terminal including a wake-up receiver (e.g., when the base station has hardware capable of transmitting a wake-up signal), the base station may determine whether to use the wake-up receiver after receiving capability information about the wake-up receiver from the terminal. In one embodiment, the base station may transmit a signal to the terminal indicating whether to use the wake-up receiver or configuration information for receiving the wake-up signal. In one embodiment, the base station may transmit to the terminal at least one of instruction information for activating the wake-up receiver of the terminal or instruction information for notifying that the base station transmits the wake-up signal. The terminal may turn off the main radio after a slot (e.g., a slot offset) configured (or defined in the standard) by the base station from a slot in which the signal indicating whether to use the wake-up receiver or configuration information for receiving the wake-up signal is received, and turn on the wake-up receiver for monitoring the wake-up signal. In one embodiment, if the serving cell measurement value remains above a specified threshold for a predetermined period of time, the terminal may turn off the main radio and turn on the wake-up receiver for monitoring the wake-up signal. In one embodiment, if the serving cell measurement value remains below a specified threshold for a predetermined period of time, the terminal may turn on the main radio. In this case, the serving cell measurement may use at least one of the measurement values ​​of the wake-up receiver or the main radio.

[0206] In one embodiment, when a base station does not support a terminal having a wake-up receiver, the base station may receive capability information about the wake-up receiver from the terminal and then transmit a signal to the terminal indicating that the wake-up receiver is unusable. The terminal may transmit feedback to the base station indicating that it has received a signal indicating that the wake-up receiver is unusable. In one embodiment, the terminal may perform an operation according to parameters of the existing power saving method set by the base station using an existing power saving method (C-DRX or I-DRX such as paging).

[0207] According to various embodiments of the present disclosure, after a capability report of a terminal having a wake-up receiver and a procedure for determining whether the wake-up receiver is supported (or permitted) by a base station, the wake-up receiver of the terminal may perform an operation for turning on the main radio of the terminal by receiving a wake-up signal. In one embodiment, the terminal may independently perform the operation for turning on the main radio, the operation for reporting the capability of the terminal having the wake-up receiver, or the operation for determining whether the wake-up receiver is supported by the base station. For example, even if the capability report operation and the permission procedure of the terminal are not performed, the base station may transmit a signal indicating whether to use the wake-up receiver or setting information for receiving the wake-up signal to the terminal. Accordingly, among terminals receiving a wake-up signal from a base station, a terminal having a wake-up receiver may perform an operation for turning on the main radio based on the wake-up signal received through the wake-up receiver.

[0208] According to one embodiment, after the capability report operation of the terminal and the base station authorization procedure are performed, the operation of the terminal turning on / off the main radio through the wake-up receiver may be applied to all terminals within the cell supported by the base station (e.g., RRC_CONNECTED terminals, RRC_IDLE / RRC_INACTIVE terminals, or terminals accessing the cell (e.g., RRC_CONNECTED terminals)). If the capability report operation of the terminal and the base station authorization procedure are not performed, the operation of turning on / off the main radio through the wake-up receiver may be applied to RRC_IDLE / RRC_INACTIVE terminals camping within the cell supported by the base station. Hereinafter, an operation of turning on the main radio of a terminal having a wake-up receiver according to embodiments of the present disclosure is described. Embodiments of the present disclosure may include at least one of all, some, or a combination of some of various operations of a terminal and a base station including a wake-up receiver as disclosed below.

[0209] According to one embodiment, when the main radio of the terminal is on, the terminal can receive a downlink signal (or data) from the base station via the main radio. According to various embodiments of the present disclosure, the main radio being 'on' may be expressed as the main radio being 'turned on' or the main radio being 'activated', and may have a similar or substantially equivalent meaning thereto. According to one embodiment, the main radio being activated may mean that specific components of the main radio (e.g., radio frequency (RF) or baseband (BB), etc.) are turned on or activated, or may be defined by a standard (e.g., 3GPP TS document). However, according to various embodiments of the present disclosure, without being limited to the above, the main radio being activated may include performing an operation by a parameter or parameter having equivalent or substantially similar content thereto.

[0210] Alternatively, it may include the main radio performing reception operations of specific channels or signals (e.g., SS / PBCH blocks containing synchronization signals or PDCCHs containing downlink control channels) defined in the 3GPP TS document.

[0211] In one embodiment, when the main radio of the terminal is off, the terminal may be considered to be in a sleep period or may not receive a downlink signal (or data) from the base station. In various embodiments of the present disclosure, the main radio being 'off' may be expressed as the main radio being 'turned off' or the main radio being 'deactivated', and may have a similar or substantially equivalent meaning thereto. In one embodiment, the main radio being deactivated may mean that specific components of the main radio (e.g., radio frequency (RF) or baseband (BB), etc.) are turned off or deactivated, or may be defined by a standard (e.g., 3GPP TS document). However, in various embodiments of the present disclosure, without being limited to the above, the main radio being deactivated may include performing an operation by a parameter or parameter having equivalent or substantially similar content thereto. Alternatively, it may include the main radio no longer performing reception operations on specific channels or signals (e.g., SS / PBCH blocks containing synchronization signals or PDCCHs containing downlink control channels) as defined in the 3GPP TS document.

[0212] According to one embodiment, a terminal having a wake-up receiver can receive a low-power synchronization signal (LP-SS) dedicated to the wake-up receiver or a PSS / SSS of an SS / PBCH block through the wake-up receiver. A terminal having a wake-up receiver capable of receiving the signal can obtain time / frequency synchronization required for receiving the wake-up signal not only through the main radio but also through the wake-up receiver. The wake-up receiver can receive at least one of the LP-SS and the PSS / SSS, or neither, depending on the terminal capability.

[0213] In describing the following embodiments, operations or procedures expressed as being performed by the main radio or wake-up receiver for a terminal equipped with a wake-up receiver (i.e., a terminal having the capability of wake-up reception) may also be understood as being performed by the terminal equipped with the wake-up receiver (i.e., a terminal having the capability of wake-up reception).

[0214] In one embodiment, the wake-up receiver of the terminal (or the terminal equipped with the wake-up receiver) can perform RRM measurement / evaluation instead of the existing RRM measurement / evaluation that the main radio of the terminal should perform when the wake-up receiver is configured or activated and turned on to detect a wake-up signal and the main radio is off. In this way, the RRM measurement / evaluation performed by the wake-up receiver of the terminal is referred to as LR (LP-WUR, Lower Power Wake-Up Receiver) RRM measurement / evaluation. The RRM measurement / evaluation performed by the existing main radio is referred to as MR (main radio, main receiver) RRM measurement / evaluation.

[0215] In one embodiment, if the main radio is off for every DRX cycle in which MR RRM measurement / evaluation is to be performed, LR RRM measurement / evaluation may be performed instead. Alternatively, a cycle for LR RRM measurement / evaluation may be separately defined in the specification. When the wake-up receiver of the terminal performs LR RRM measurement, the signal to be measured may be at least one of the PSS / SSS, LP-SS, and wake-up signal included in the existing SS / PBCH block.

[0216] In describing the following embodiments, the measurement of a neighboring cell may be understood as a measurement including at least one of an intra-frequency cell, an inter-frequency cell, or an inter-RAT (Radio Access Technology) cell, depending on a triggering condition. In this case, an intra-frequency cell is a cell among adjacent cells whose center frequency is the same as that of the serving cell, an inter-frequency cell is a cell whose center frequency is different from that of the serving cell, and an inter-RAT cell may refer to a cell of a different communication technology generation, such as E-UTRAN or NR.

[0217] [Example 2: LP-WUS / WUR PTW in eDRX]

[0218] The terminal receives an eDRX (extended DRX) cycle T from the upper layer (or RRC). eDRX,CN or T eDRX,RAN can be set. If eDRX is configured from a higher layer or eDRX-AllowedIdle is signaled in SIB1 for a terminal in RRC_IDLE / RRC_INACTIVE state, the terminal can receive CN paging messages. If ran-ExtendedPagingCycle and eDRX-AllowedInactive are configured in RRC_INACTIVE state, the terminal can receive RAN paging messages. The terminal can search for paging messages in a periodically configured PTW (paging time window). PTW can be configured specifically for the terminal, and the start and end H-SFN (hyper system frame number) can be set by PH (paging hyperframe). H-SFN is a bundle of SFN (system frame numbers) and can set PH in a longer time unit.

[0219] According to one embodiment, FIG. 6 illustrates an example of a terminal searching for a paging message in PTW when eDRX is configured.

[0220] When eDRX is configured, the terminal can detect a paging message at a paging occasion (602) within the PTW (601). The PTW is repeated every eDRX cycle (603), and the paging message can be detected every DRX cycle (604). The length of the PTW can be configured in seconds, and can be increased or decreased in units of 1.28 seconds. When the terminal is configured with eDRX, the terminal can detect a paging message at a paging occasion (602) within a single PTW. serv During the DRX cycle, it is evaluated whether the serving cell satisfies the cell selection / reselection criterion S, and if the serving cell does not satisfy the cell selection / reselection criterion S, the terminal can initiate measurements of all neighboring cells indicated from the serving cell regardless of the measurement rules that are currently limiting the measurement activities of the terminal.

[0221] At this time, the minimum length of PTW is ceil(N serv *DRX_cycle / 1.28)*1.28s (DRX_cycle is the DRX cycle period). The minimum requirement for the terminal as above is to give the terminal enough time to evaluate the serving cell within the PTW. If the link condition of the terminal is not good and the serving cell evaluation is not performed properly within the PTW, the terminal may not perform cell reselection and may miss the paging message within the PTW. Since the network has to wait a long time until the next PTW to wake up the terminal, the delay time may be long. Therefore, the minimum length of the PTW must ensure sufficient time for the terminal to evaluate and reselect the serving cell. In other words, the minimum length of the PTW is N consecutive periods to evaluate the serving cell. serv It should be decided in relation to the DRX cycle.

[0222] In one embodiment, when a terminal equipped with a wake-up receiver turns on the wake-up receiver, detects a wake-up signal, and turns off the main radio, the terminal can perform serving cell RRM measurement / detection using the wake-up receiver. The terminal can measure / detect the serving cell by detecting an LP-SS or PSS / SSS using the wake-up receiver. Since the performance of the wake-up receiver is typically worse than that of the main radio, the serving cell measurement time of the wake-up receiver may take longer than the serving cell measurement time of the main radio.

[0223] For example, when a wake-up receiver detects an LP-SS, since the waveform of the LP-SS does not follow the orthogonal frequency division multiplexing (OFDM) scheme but the on-off keying (OOK) scheme, the signal can be detected through simpler energy detection or envelope detection. Since the signal detection method above incurs performance degradation compared to the OFDM scheme that can use phase information, it may need to receive and process signals of relatively more symbols, slots, or periods. On the other hand, when the wake-up receiver detects a PSS / SSS, it may also need to receive more periods of PSS / SSS due to degraded reception performance (e.g., large noise figure). Therefore, the minimum requirements for serving cell measurement / detection of the wake-up receiver may be different from those of the main radio.

[0224] For example, N of the wake-up receiver serv_LP_WUR is the main radio N serv It can be greater than N consecutive DRX cycles required for the wakeup receiver to evaluate the serving cell. serv_LP_WURmay be applied to at least one of the requirements of LP-SS or PSS / SSS measured / detected by the wake-up receiver. In the following disclosure, N serv_LP_WUR is applied regardless of whether the wake-up receiver measures / detects LP-SS or PSS / SSS, but different values ​​may be applied depending on the signal that the wake-up receiver can measure / detect.

[0225] In one embodiment, when a UE equipped with a wake-up receiver in RRC IDLE or RRC INACTIVE state is configured for eDRX, it is required to perform serving cell evaluation within the PTW. When the main radio is off, the wake-up receiver is on, and the wake-up signal is detected, the wake-up receiver is required to perform RRM measurement / detection at every DRX cycle set in the PTW for serving cell (or camping cell) related measurements. In this case, the length of the PTW is N of the main radio. serv If the minimum length is required based on the value, and the N of the wakeup receiver serv_LP_WUR If has a larger value, it may be difficult for the wake-up receiver to evaluate the serving cell within the PTW. The minimum size of the PTW when the wake-up receiver measures / detects the serving cell is N serv_LP_WUR One way to consider it is to have a value that is larger than that.

[0226] However, if the PTW length is changed based on whether the wake-up receiver is activated, a mismatch may occur between the network and the terminal's understanding of the PTW length. Since the terminal detects the wake-up signal with the wake-up receiver and does not report to the network whether it performs LR RRM measurement / detection, the network cannot determine when the terminal's wake-up receiver is activated. Therefore, a mismatch in the network and terminal's understanding of the PTW length may occur, resulting in problems with correctly transmitting and receiving paging messages. The following describes a method to resolve this issue.

[0227] FIG. 7 is a flowchart illustrating a method for a terminal equipped with a wake-up receiver to apply PTW requirements according to an embodiment of the present disclosure when eDRX is configured. In this case, the PTW requirements may be enhanced PTW requirements.

[0228] Referring to FIG. 7, in step 701, a terminal equipped with a wake-up receiver may receive settings for a wake-up signal from a higher layer and may receive eDRX settings. In addition, the terminal may perform LR RRM measurement / detection and may receive settings related to LR RRM measurement / detection from a higher layer. Upon receiving the above settings, the terminal may perform step 702 regardless of wake-up signal detection.

[0229] At step 702, the terminal may apply enhanced PTW requirements or settings. The enhanced PTW requirements or settings may include at least one of the methods described below.

[0230] - The terminal may transmit an uplink signal or channel to the base station to notify the detection of the wakeup signal at the latest before starting the wakeup signal detection. The terminal may transmit an uplink signal or channel to the base station to notify the detection of the wakeup signal at the latest before stopping the wakeup signal detection. The terminal may receive settings for the related signal or channel from the upper layer. The terminal may perform the wakeup signal detection while the minimum length of the PTW is at least N consecutive serv_LP_WUR may be required to be greater than the DRX cycle. For example, the minimum length of PTW is ceil (N serv_LP_WUR *DRX_cycle / 1.28)*1.28s may be requested. If the terminal does not perform wake-up signal detection, the minimum length of the main radio PTW may be applied.

[0231] - The terminal must have a minimum length of PTW of at least N consecutive serv_LP_WUR may be required to be greater than the DRX cycle. For example, the minimum length of PTW is ceil (N serv_LP_WUR *DRX_cycle / 1.28)*1.28s may be requested.

[0232] - The terminal has a PTW minimum length of N consecutive serv Wow N serv_LP_WUR It may be required to be determined according to the larger value during the DRX cycle. For example, the minimum length of PTW is ceil (max(N serv , N serv_LP_WUR )*DRX_cycle / 1.28)*1.28s may be requested.

[0233] - N serv_LP_WUR this N serv If greater than N, the terminal is limited to the minimum length of PTW. servConsecutive DRX cycles may be applied. If the terminal performs wake-up signal detection, the terminal may be requested to measure the serving cell at least a certain time before the PTW starts. The terminal may perform serving cell measurement / detection and evaluation for at least a certain time before the PTW starts and for the length of the PTW. If the terminal does not perform wake-up signal detection, the terminal may not be requested to measure the serving cell at least a certain time before the PTW starts. The certain time may be determined by at least one of the following methods.

[0234] The terminal must be started by PTW at the latest (N serv_LP_WUR - N serv ) may be required to measure the serving cell before the DRX cycle.

[0235] The terminal must be at least as late as PTW starts (ceil(N serv_LP_WUR *DRX_cycle / 1.28)*1.28s - ceil(N serv *DRX_cycle / 1.28)*1.28s) seconds ago may be requested to measure the serving cell.

[0236] The terminal is N at the latest when PTW starts serv_LP_WUR You may be asked to measure the serving cell before the DRX cycle.

[0237] The terminal must be at least ceil(N) before PTW starts. serv_LP_WUR *DRX_cycle / 1.28)*1.28s may be requested to measure the serving cell.

[0238] [Example 3: LP-WUS / WUR maximum interruption in paging reception]

[0239] The following description describes the maximum interruption in paging reception requirement. The maximum interruption in paging reception refers to the time allowed for the UE to drop paging when acquiring system information of a neighboring cell when cell reselection occurs. The UE shall perform cell reselection with the minimum interruption time to search the downlink channel for receiving paging messages. In addition, if the UE is set to an eDRX_IDLE cycle, the UE shall not miss the paging message provided within the PTW at least 2 DRX cycles before the PTW ends. In intra-frequency cell reselection and inter-frequency cell reselection, the UE shall search the downlink of the serving cell for receiving paging messages until it can start the downlink channel search for intra-frequency cell reselection and inter-frequency cell reselection for receiving paging messages. The interruption time is T SI-NR It must not exceed +2*Ttarget_cell_SMTC_periodms, where Ttarget_cell_SMTC_period is the SMTC period of the target NR cell. If the target cell is in the PCI list of smtc2-LP, the SMTC period must follow smtc2-LP; otherwise, the SMTC period follows smtc.

[0240] In inter-RAT (radio access technology) cell reselection, the UE must search the downlink of the serving cell for paging message reception until it can start searching the downlink channel for target inter-RAT cell reselection for paging message reception. In case of E-UTRAN cell reselection from NR, the downlink time is T SI-EUTRA + Must not exceed 55 ms. T SI-NRis the time required to receive all related system information data according to the reception procedure of the system information block defined in TS38.331 for the NR cell and the RRC processing delay time. T SI-EUTRA is the time required to receive all relevant system information data according to the reception procedure of the system information block defined in TS36.331 for an E-UTRAN cell and the RRC processing delay time. The above requirement assumes sufficient radio environment conditions, and therefore, the decoding of the system information must be performed without errors and does not consider cell reselection failure.

[0241] According to one embodiment, when a terminal equipped with a wake-up receiver, detects a wake-up signal, performs LR RRM measurement / detection, and the main radio is off and performs cell reselection, the terminal can turn on the main radio, receive a system information block according to required conditions, and perform cell reselection. More specifically, the terminal can determine cell reselection by comparing the RSRP or RSRQ of the serving cell measured by the wake-up receiver or the main radio with the RSRP or RSRQ of the neighboring cells. According to one embodiment of the present disclosure, when a terminal equipped with a wake-up receiver determines cell reselection, the terminal can switch the main radio from off to on, synchronize with the serving cell so that the main radio can normally search for a downlink control channel while the main radio is on, and perform AGC (adaptive gain control). The terminal, which has completed synchronization with the serving cell and adjustment of the AGC, can perform a system information reception procedure and an operation of synchronizing with the target cell in time / frequency.

[0242] At this time, according to the maximum paging interruption time requirement described above, the operation of the main radio to receive system information and synchronize time / frequency with the target cell is included, but the operation of the main radio switching from off to on and adjusting the synchronization and AGC of the serving cell is not included. The time for the main radio to switch on from the UDS state is known to require a long time of at least 400 ms, depending on the terminal capability. In addition, it is known that up to 10 SMTC cycles are required to adjust the synchronization and AGC of the main radio. Since the terminal cannot receive the paging message during the operation of the main radio switching from off to on and adjusting the synchronization and AGC of the serving cell, it may be difficult for the terminal equipped with the wake-up receiver to satisfy the maximum paging interruption time requirement. The present disclosure describes a method to solve this problem.

[0243] According to one embodiment, FIG. 8 illustrates a block diagram illustrating an example of applying a maximum paging interruption time requirement when a terminal equipped with a wake-up receiver performs cell reselection. In this case, the maximum paging interruption time requirement may be an enhanced page interruption maximum time requirement.

[0244] Referring to FIG. 8, in step 801, the terminal is equipped with a wake-up receiver, detects a wake-up signal, and can perform LR RRM measurement / detection, while the main radio may be in an off state. At this time, the terminal can trigger neighboring cell measurement / detection and compare and evaluate the serving cell measurement values ​​with neighboring measurement values. If cell reselection is performed based on the cell reselection decision, the terminal can perform step 802.

[0245] In step 802, the terminal must search the downlink of the serving cell for receiving paging messages until it can start searching the downlink channel for cell reselection within the target frequency and cell reselection between frequencies for cell reselection within the target frequency for receiving paging messages. At this time, the interruption time is T SI-NR + 2*Ttarget_cell_SMTC_period+ T transition_MR + X*Tserving_cell_SMTC_periodms must not be exceeded. In this case, the interruption time may include at least one of the following information:

[0246] - T transition_MR is the time required for the main radio to transition from an off state to an on state. This value can be either a value provided by the terminal implementation or a value reported to the network through the terminal capability report.

[0247] - Tserving_cell_SMTC_period is the SMTC period of the serving cell. The SMTC period can follow smtc.

[0248] - X represents the number of SMTC cycles required to adjust the synchronization and AGC of the main radio. X can use any value required depending on the RF components of the radio and the wake-up receiver. When using any value required depending on the RF components of the main radio and the wake-up receiver, X can include at least one of the following values.

[0249] o When X=0, the main radio and the wake-up receiver share RF components, so they can share synchronization and AGC information. In this case, the synchronization and AGC information of the wake-up receiver can be used to align the synchronization and AGC of the main radio.

[0250] o If X is less than or equal to 2 or 3, the main radio and the wake-up receiver may partially share RF components, and thus partially share synchronization and AGC information. In this case, the synchronization and AGC information of the wake-up receiver may be partially used to align the synchronization and AGC of the main radio.

[0251] o If X is greater than 4, the main radio and wakeup receiver do not share RF components and may not share sync and AGC information. In this case, the sync and AGC information of the wakeup receiver is not used and may be used to align the sync and AGC of the main radio.

[0252] The above X value may include at least one of a fixed value defined in the standard, a value determined by the terminal through implementation, and a value reported to the network as a terminal capability report.

[0253] In step 802, in inter-RAT (radio access technology) cell reselection, the UE must search the downlink of the serving cell for receiving paging messages until it can start searching the downlink channel for target inter-RAT cell reselection for receiving paging messages. In case of E-UTRAN cell reselection from NR, the downlink time is T SI-EUTRA + 55 + T transition_MR + X*Tserving_cell_SMTC_periodms must not be exceeded. In this case, the interruption time may include at least one of the following information:

[0254] - T transition_MR is the time required for the main radio to transition from an off state to an on state. This value can be either a value provided by the terminal implementation or a value reported to the network through the terminal capability report.

[0255] - Tserving_cell_SMTC_period is the SMTC period of the serving cell. The SMTC period can follow smtc.

[0256] - X represents the number of SMTC cycles required to adjust the synchronization and AGC of the main radio. X can use any value required depending on the RF components of the radio and the wake-up receiver. When using any value required depending on the RF components of the main radio and the wake-up receiver, X can include at least one of the following values.

[0257] o When X=0, the main radio and the wake-up receiver share RF components, so they can share synchronization and AGC information. In this case, the synchronization and AGC information of the wake-up receiver can be used to align the synchronization and AGC of the main radio.

[0258] o If X is less than or equal to 2 or 3, the main radio and the wake-up receiver may partially share RF components, and thus partially share synchronization and AGC information. In this case, the synchronization and AGC information of the wake-up receiver may be partially used to align the synchronization and AGC of the main radio.

[0259] o If X is greater than 4, the main radio and wakeup receiver do not share RF components and may not share sync and AGC information. In this case, the sync and AGC information of the wakeup receiver is not used and may be used to align the sync and AGC of the main radio.

[0260] The above X value may include at least one of a fixed value defined in the standard, a value determined by the terminal through implementation, and a value reported to the network as a terminal capability report.

[0261] FIG. 9 is a block diagram illustrating the functional structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0262] Referring to FIG. 9, the terminal may include a terminal receiving unit (900), a terminal transmitting unit (910), and a terminal processing unit (control unit) (905).

[0263] The terminal receiving unit (900) and the terminal transmitting unit (910) may be collectively referred to as a transceiver. Depending on the communication method of the terminal described above, the terminal receiving unit (900), the terminal transmitting unit (910), and the terminal processing unit (905) of the terminal may operate. However, the components of the terminal are not limited to the examples described above. For example, the terminal may include more or fewer components (e.g., memory, etc.) than the components described above. In addition, the terminal receiving unit (900), the terminal transmitting unit (910), and the terminal processing unit (905) may be implemented in the form of a single chip. According to one embodiment, the receiving unit (900) of FIG. 9 may include the main radio (504) and the wake-up receiving unit (502) of FIG. 5.

[0264] The terminal receiving unit (900) and the terminal transmitting unit (910) (or, transceiver) can transmit and receive signals with a base station. Here, the signals can include control information and data. To this end, the transceiver can be configured with an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and frequency-converts a received signal. However, this is only one embodiment of the transceiver, and the components of the transceiver are not limited to the RF transmitter and RF receiver.

[0265] In addition, the transceiver can receive a signal through a wireless channel and output it to the terminal processing unit (905), and transmit a signal output from the terminal processing unit (905) through the wireless channel.

[0266] Memory (not shown) can store programs and data necessary for the operation of the terminal. Furthermore, the memory can store control information or data included in signals acquired from the terminal. The memory may be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media.

[0267] The terminal processing unit (905) can control a series of processes so that the terminal can operate according to the embodiments of the present disclosure described above. The terminal processing unit (905) can be implemented as a control unit or one or more processors.

[0268] FIG. 10 is a block diagram illustrating the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0269] Referring to FIG. 10, the base station may include a base station receiving unit (1000), a base station transmitting unit (1010), and a base station processing unit (control unit) (1005).

[0270] The base station receiving unit (1000) and the base station transmitting unit (1010) may be collectively referred to as a transceiver. Depending on the communication method of the base station described above, the base station receiving unit (1000), the base station transmitting unit (1010), and the base station processing unit (1005) of the base station may operate. However, the components of the base station are not limited to the examples described above. For example, the base station may include more or fewer components (e.g., memory, etc.) than the components described above. In addition, the base station receiving unit (1000), the base station transmitting unit (1010), and the base station processing unit (1005) may be implemented in the form of a single chip.

[0271] The base station receiving unit (1000) and the base station transmitting unit (1010) (or, transmitting and receiving unit) can transmit and receive signals with the terminal. Here, the signals can include control information and data. To this end, the transmitting and receiving unit can be configured with an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and frequency-converts a received signal. However, this is only one embodiment of the transmitting and receiving unit, and the components of the transmitting and receiving unit are not limited to the RF transmitter and RF receiver.

[0272] In addition, the transceiver unit can receive a signal through a wireless channel and output it to the base station processing unit (1005), and transmit the signal output from the base station processing unit (1005) through the wireless channel.

[0273] Memory (not shown) can store programs and data necessary for the operation of the base station. Furthermore, the memory can store control information or data contained in signals acquired from the base station. The memory may be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media.

[0274] The base station processing unit (1005) may control a series of processes so that the base station can operate according to the embodiments of the present disclosure described above. For example, the base station transmitting unit (1010) may be controlled to transmit a wake-up signal to the terminal to instruct the terminal to activate / deactivate the wake-up receiving unit, or to turn the main radio of the terminal ON / OFF, according to the embodiments of the present disclosure. The base station processing unit (1005) may be implemented as a control unit or one or more processors.

[0275] Meanwhile, the order of description in the drawings explaining the method of the present disclosure does not necessarily correspond to the order of execution, and the order of precedence may be changed or executed in parallel.

[0276] Alternatively, the drawings illustrating the method of the present disclosure may omit some components and include only some components without detracting from the essence of the present disclosure.

[0277] In addition, the method of the present disclosure may be implemented by combining some or all of the contents included in each embodiment within a scope that does not harm the essence of the invention.

[0278] Additionally, although not disclosed in the present disclosure, a method in which a separate table or information including at least one component included in the table proposed in the present disclosure is used is also possible.

[0279] Meanwhile, the embodiments of the present disclosure disclosed in this specification and drawings are merely specific examples presented to easily explain the technical content of the present disclosure and aid in understanding of the present disclosure, and are not intended to limit the scope of the present disclosure. In other words, it will be apparent to those skilled in the art to which the present disclosure pertains that other modified examples based on the technical concept of the present disclosure are possible. Furthermore, the above-described embodiments may be combined and operated as needed.

Claims

1. In a method performed by a UE (user equipment) in a wireless communication system, A step of receiving setup information regarding radio resource management (RRM) in a wake-up receiver from a base station; The number of DRX (discontinuous reception) for serving cell evaluation in the wake-up receiver Based on this, a step of determining the length of PTW (paging time window); and A method comprising the step of performing RRM for a serving cell using the wake-up receiver within a PTW of the determined length.

2. In the first paragraph, the step of performing the RRM comprises: A method for performing the RRM for at least one of a LP-SS (low-power synchronization signal), a wake-up signal, a PSS (primary synchronization signal) or an SSS (secondary synchronization signal) included in an SS / PBCH (synchronization signal / physical broadcast channel) block.

3. In the first paragraph, the step of determining the length of the PTW is: If a wake-up signal is detected: A step of transmitting an uplink signal to a base station to notify detection of the wake-up signal based on the upper layer setting; and The minimum length of the above PTW Including a step of determining a DRX cycle greater than the number of DRX cycles, If the above wake-up signal is not detected: The minimum length of the above PTW Including a step of determining a DRX cycle greater than the number of DRX cycles, A method for evaluating a serving cell in a main radio, the number of DRXs.

4. In the first paragraph, the step of determining the length of the PTW is: The minimum length of the above PTW A method comprising the step of determining a DRX cycle greater than the number of cycles.

5. In the first paragraph, the step of determining the length of the PTW is: and the number of DRXs for serving cell evaluation on the main radio. A method comprising the step of determining the minimum length of the PTW based on a larger value.

6. In the first paragraph, the step of determining the length of the PTW is: The number of DRXs for serving cell evaluation on the main radio If it is larger than Including a step of determining the length of the PTW based on the The above method, Further comprising a step of performing RRM for the serving cell from a time set before the PTW, The above preset time is A method determined based on.

7. In paragraph 1, When cell reselection is determined by comparing the RRM for the serving cell with the RRM for the surrounding cells, the maximum interruption time for receiving paging messages is determined. , and Further comprising a step of determining based on is the time required to receive a SIB (system information block), is the time required for the main radio to switch from off to on. is the SMTC (SSB-based measurement timing configuration) cycle of the target cell, A method in which the number of SMTC cycles required to adjust the synchronization and AGC (adaptive gain control) of the main radio is indicated.

8. In paragraph 7, A method wherein at least one of a predefined value, a value determined by the UE, and a value reported through a UE capability report.

9. In a wireless communication system, in the UE (user equipment), A transceiver including a wake-up receiver; and At least one processor communicatively coupled to the transceiver; and A memory communicatively coupled to at least one processor and storing one or more instructions, The one or more instructions, when individually or collectively executed by the at least one processor, cause the UE to: Receive configuration information regarding RRM (radio resource management) in a wake-up receiver from a base station, The number of DRX (discontinuous reception) for serving cell evaluation in the wake-up receiver Based on this, the length of PTW (paging time window) is determined, A UE that performs RRM for a serving cell using the wake-up receiver within a PTW of the determined length.

10. In paragraph 9, the one or more commands, when individually or in combination executed by the at least one processor, cause the UE to further: A UE that performs the RRM for at least one of a LP-SS (low-power synchronization signal), a wake-up signal, a PSS (primary synchronization signal) or an SSS (secondary synchronization signal) included in an SS / PBCH (synchronization signal / physical broadcast channel) block.

11. In paragraph 9, the one or more commands, when individually or in combination executed by the at least one processor, cause the UE to further: If a wake-up signal is detected: Based on the upper layer settings, an uplink signal is transmitted to the base station to notify the detection of the wake-up signal, The minimum length of the above PTW It is decided to be larger than the DRX cycle of the dog, If the above wake-up signal is not detected: The minimum length of the above PTW Let's make a decision bigger than the DRX cycle of the dog, is the number of DRXs for serving cell evaluation on the main radio, UE.

12. In paragraph 9, the one or more commands, when individually or in combination executed by the at least one processor, cause the UE to further: The minimum length of the above PTW The UE decides which DRX cycle is larger than the dog's.

13. In paragraph 9, the one or more commands, when individually or in combination executed by the at least one processor, cause the UE to further: and the number of DRXs for serving cell evaluation on the main radio. UE to determine the minimum length of the PTW based on the larger value.

14. In paragraph 9, the one or more commands, when individually or in combination executed by the at least one processor, cause the UE to further: The number of DRXs for serving cell evaluation on the main radio If it is larger than Determine the length of the PTW based on Perform RRM for the serving cell from a time set before the above PTW, The above preset time is UE, which is determined based on.

15. In paragraph 9, the one or more commands, when individually or in combination executed by the at least one processor, cause the UE to further: When cell reselection is determined by comparing the RRM for the serving cell with the RRM for the surrounding cells, the maximum interruption time for receiving paging messages is determined. , and Further comprising a step of determining based on is the time required to receive a SIB (system information block), is the time required for the main radio to switch from off to on. is the SMTC (SSB-based measurement timing configuration) cycle of the target cell, The UE indicates the number of SMTC cycles required to adjust the synchronization and AGC (adaptive gain control) of the main radio.

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