Method and apparatus for transmitting / receiving system information for cell (RE)selection in wireless communication system

Abstract

The present disclosure relates to a method and an apparatus for efficiently transmitting / receiving system information for cell (re)selection in a wireless communication system. The method by which a terminal receives system information in a wireless communication system, according to an embodiment of the disclosure, comprises steps in which the terminal being in an RRC connection with a first base station of a first cell: transmits, to the first base station, terminal capability information for reception of the system information; and, on the basis of the terminal capability information, receives, from the first base station, an RRC connection release message including configuration information for cell selection or cell reselection of the terminal, wherein the configuration information includes at least a part of the system information about a second cell, which is a candidate target cell for the cell selection or the cell reselection, and / or information for the reception of the system information.

Description

Method and device for transmitting and receiving system information for cell (re)selection in a wireless communication system

[0001] The present disclosure relates to a method and device for transmitting and receiving system information 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] The present disclosure provides a method and device for efficiently transmitting and receiving system information for cell (re)selection in a wireless communication system.

[0009] Additionally, the present disclosure provides a method and device for a terminal to efficiently perform cell (re)selection in a wireless communication system.

[0010] Additionally, the present disclosure provides a method and device for a terminal to efficiently report information related to cell (re)selection in a wireless communication system.

[0011] According to an embodiment of the present disclosure, a method for a terminal to receive system information in a wireless communication system includes a process in which the terminal, which is in an RRC (radio resource control) connection state with a first base station of a first cell, transmits terminal capability information for receiving the system information to the first base station, and a process in which the terminal receives an RRC connection release message including configuration information for cell selection or cell reselection of the terminal from the first base station based on the terminal capability information, wherein the configuration information may include at least one of at least a part of the system information for a second cell which is a candidate target cell for the cell selection or the cell reselection and information for receiving the system information.

[0012] In one embodiment, the system information includes a system information block 1 (SIB1) of the second cell, and the terminal capability information may include at least one of capability information capable of transmitting a wake-up signal (WUS) for requesting provision of the SIB1 on-demand to a second base station of the second cell that transmits the SIB1, capability information capable of receiving SIB1 per cell or per cell list through the RRC connection release message, and capability information capable of receiving some SIB1 per cell or per cell list through the RRC connection release message.

[0013] In one embodiment, the system information includes SIB1 of the second cell, and the configuration information may include at least one of SIB1 per cell, SIB1 per cell list, SIB1 per frequency, and measurement-related parameters for the candidate target cell.

[0014] In one embodiment, the method may further include a process in which the terminal, having received the RRC connection release message, transitions from the RRC connection state to an RRC idle state or an RRC inactive state, and a process in which a cell selection or cell reselection procedure for the second cell is performed based on the configuration information included in the RRC connection release message.

[0015] In one embodiment, the RRC connection release message may further include timer information indicating the applicable period of the configuration information.

[0016] In addition, according to an embodiment of the present disclosure, in a wireless communication system, a terminal includes a transceiver, and a processor configured to transmit terminal capability information for receiving the system information to the first base station through the transceiver in an RRC connection state with a first base station of a first cell, and to receive, based on the terminal capability information, an RRC connection release message including configuration information for cell selection or cell reselection of the terminal from the first base station through the transceiver, wherein the configuration information includes at least one of at least a part of the system information for a second cell which is a candidate target cell for the cell selection or the cell reselection and information for receiving the system information.

[0017] In addition, according to an embodiment of the present disclosure, in a wireless communication system, a base station includes a transceiver, and a processor configured to transmit, through the transceiver, terminal capability information related to transmission of system information from a terminal in an RRC connection state with the base station of a first cell, and to transmit, through the transceiver, an RRC connection release message including configuration information for cell selection or cell reselection of the terminal to the terminal based on the terminal capability information, wherein the configuration information may include at least one of at least a part of the system information for a second cell which is a candidate target cell for the cell selection or the cell reselection and information for transmission of the system information.

[0018] FIG. 1 is a diagram illustrating the structure of an LTE system according to one embodiment of the present disclosure.

[0019] FIG. 2 is a diagram illustrating a wireless protocol structure in an LTE system according to an embodiment of the present disclosure.

[0020] FIG. 3 is a diagram illustrating the structure of a wireless communication system according to an embodiment of the present disclosure.

[0021] FIG. 4 is a diagram illustrating a wireless protocol structure of a wireless communication system according to an embodiment of the present disclosure.

[0022] FIG. 5 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for periodically transmitting essential system information in a wireless communication system according to an embodiment of the present disclosure.

[0023] FIG. 6 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for transmitting System Information Block 1 (SIB1) on-demand in a wireless communication system according to an embodiment of the present disclosure.

[0024] FIG. 7 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for transmitting System Information Block 1 (SIB1) on-demand in a wireless communication system according to an embodiment of the present disclosure.

[0025] FIG. 8 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for transmitting System Information Block 1 (SIB1) on-demand in a wireless communication system according to an embodiment of the present disclosure.

[0026] FIG. 9 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for transmitting System Information Block 1 (SIB1) on-demand in a wireless communication system according to an embodiment of the present disclosure.

[0027] FIG. 10 is a diagram illustrating a procedure in which a terminal performs a random access procedure with a base station to request System Information Block 1 (SIB1) and reports information related thereto to the base station in a wireless communication system according to an embodiment of the present disclosure.

[0028] FIG. 11 is a diagram illustrating a procedure in which a terminal performs a random access procedure with a base station to request System Information Block 1 (SIB1) and reports information related thereto to the base station in a wireless communication system according to an embodiment of the present disclosure.

[0029] FIG. 12 is a diagram illustrating a terminal operation in a wireless communication system according to an embodiment of the present disclosure in which the terminal stores mobility history information and reports it to a base station.

[0030] FIG. 13 is a block diagram illustrating the internal structure of a terminal according to an embodiment of the present disclosure.

[0031] FIG. 14 is a block diagram showing the configuration of an NR base station according to one embodiment of the present disclosure.

[0032] The operating principles of the present disclosure are described in detail below with reference to the attached drawings. 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. Furthermore, the terms described below are defined based on the functions of the present disclosure and may vary depending on the intent or custom of the user or operator. Therefore, their definitions should be based on the overall content of this specification.

[0033] 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.

[0034] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described in detail below 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 disclosure of the present disclosure is complete and to fully inform those skilled in the art of the scope of the invention, and the present disclosure is defined only by the scope of the claims. Like reference numerals designate like elements throughout the specification.

[0035] At this time, it will be understood that each block of the processing flow diagrams and combinations of the flow diagrams can be performed by computer program instructions.

[0036] 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.

[0037] 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.

[0038] In this disclosure, phrases such as "A and / or B", "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", and "at least one of A, B, or C" can each include any one of the items listed together in that phrase, or all possible combinations thereof. Terms such as "first", "second", or "first" or "second" may be used merely to distinguish the corresponding component from other corresponding components and do not limit the corresponding components in any other respect (e.g., importance or order).

[0039] The terms used in the description of this disclosure 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, and the like are provided 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.

[0040] For convenience of explanation, this disclosure uses terms and names defined in the 5GS and NR standards defined by the 3rd Generation Partnership Project (3GPP), among the existing communication standards. However, this disclosure is not limited to the above terms and names and can be equally applied to wireless communication systems that comply with other standards. This disclosure can be applied to 3GPP 5GS / NR (5th generation mobile communication standards).

[0041] In the present disclosure, a base station is an entity that performs resource allocation of a terminal, and may be at least one of an eNode B, a Node B, a BS (Base Station), a RAN (Radio Access Network), an AN (Access Network), a RAN node, a wireless access unit, a base station controller, or a node on a network. A user equipment (UE) may be at least one of a terminal, an MS (Mobile Station), a cellular phone, a smartphone, a computer, or an electronic device capable of performing a communication function. In the present disclosure, a downlink (DL) refers to a wireless transmission path of a signal transmitted from a base station to a terminal, and an uplink (UL) refers to a wireless transmission path of a signal transmitted from a terminal to a base station. In addition, although the embodiments of the present disclosure are described below using an LTE or LTE-A system as an example, the embodiments of the present disclosure may be applied to other communication systems having a similar technical background or channel type. In addition, the embodiments of the present disclosure may be applied to other communication systems with some modifications without significantly departing from the scope of the present disclosure at the discretion of a person having skilled technical knowledge.

[0042] Meanwhile, the 3rd Generation Partnership Project (3GPP), which is responsible for cellular mobile communication standards, is naming a new core network structure 5G Core (5GC) and standardizing it to facilitate the evolution from the existing 4G LTE system to the 5G system. 5GC supports the following differentiated functions compared to the Evolved Packet Core (EPC), the network core for the existing 4G.

[0043] 5GC introduces the Network Slice feature. As a requirement of the 5G system, 5GC can support various types of terminal types and services (e.g., enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency Communications (URLLC), massive Machine Type Communications (mMTC)). Each of these terminals / services has different requirements for the core network. For example, eMBB service requires a high data rate, while URLLC service requires high stability and low latency. The technology proposed to satisfy these various service requirements is Network Slice (or network slicing).

[0044] 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, and terms referring to various identification information 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.

[0045] For convenience of explanation, this disclosure uses terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP) LTE / NR standard. However, this disclosure is not limited to the above terms and names and can be equally applied to systems conforming to other standards. In this disclosure, eNB may be used interchangeably with gNB for convenience of explanation. That is, a base station described as an eNB may also represent a gNB.

[0046] FIG. 1 is a diagram illustrating the structure of an LTE system according to one embodiment of the present disclosure.

[0047] Referring to FIG. 1, as illustrated, an LTE system may include a base station (e.g., Evolved Node B, hereinafter ENB or Node B) (105, 110, 115, 120), an MME (125, Mobility Management Entity), and an S-GW (130, Serving-Gateway). A user equipment (UE or terminal) (135) connects to an external network through the ENB (105 to 120) and the S-GW (130).

[0048] In Fig. 1, ENBs (105 to 120) correspond to existing Node Bs of the UMTS (Universal Mobile Telecommunication System) system. ENBs are connected to UEs (135) via a wireless channel and perform a more complex role than existing Node Bs. In the LTE system, all user traffic, including real-time services such as VoIP (Voice over IP) via the Internet Protocol, is serviced through a shared channel. Therefore, a device that collects status information such as buffer status, available transmission power status, and channel status of UEs and performs scheduling is required, and ENBs (105 to 120) are in charge of this. One ENB typically controls multiple cells. For example, in order to implement a transmission speed of 100 Mbps, the LTE system uses, for example, orthogonal frequency division multiplexing (OFDM) as a wireless access technology in a 20 MHz bandwidth. In addition, an adaptive modulation and coding (AMC) method is applied, which determines the modulation scheme and channel coding rate according to the channel condition of the terminal. The S-GW (130) is a device that provides data bearers and creates or removes data bearers according to the control of the MME (125). The MME is a device that is responsible for various control functions as well as mobility management functions for the terminal and is connected to multiple base stations.

[0049] FIG. 2 is a diagram illustrating a wireless protocol structure in an LTE system according to an embodiment of the present disclosure.

[0050] Referring to Figure 2, the wireless protocol stack of the LTE system includes PDCP (Packet Data Convergence Protocol 205, 240), RLC (Radio Link Control 210, 235), and MAC (Medium Access Control 215, 230) in the terminal and ENB, respectively. PDCP (Packet Data Convergence Protocol) (205, 240) is responsible for operations such as IP header compression / decompression. The main functions of PDCP are summarized as follows.

[0051] - Header compression and decompression (ROHC (robust header compression) only)

[0052] - User data transfer function

[0053] - In-sequence delivery of upper layer PDUs (packet data units) at PDCP re-establishment procedure for RLC AM

[0054] - Order reordering function (For split bearers in DC(dual connectivity) (only support for RLC AM): PDCP PDU routing for transmission and PDCP PDU reordering for reception)

[0055] - Duplicate detection function (Duplicate detection of lower layer SDUs (service data units) at PDCP re-establishment procedure for RLC AM (acknowledge mode))

[0056] - Retransmission function (Retransmission of PDCP SDUs at handover and, for split bearers in DC, of ​​PDCP PDUs at PDCP data-recovery procedure, for RLC AM)

[0057] - Encryption and decryption functions (Ciphering and deciphering)

[0058] - Timer-based SDU discard in uplink.

[0059] Radio Link Control (RLC) (210, 235) reconfigures PDCP PDUs into an appropriate size and performs ARQ operations, etc. The main functions of RLC are summarized as follows.

[0060] - Data transfer function (Transfer of upper layer PDUs)

[0061] - ARQ function (Error Correction through ARQ (only for AM data transfer))

[0062] - Concatenation, segmentation and reassembly of RLC SDUs (only for UM (unacknowledge mode) and AM data transfer)

[0063] - Re-segmentation of RLC data PDUs (only for AM data transfer)

[0064] - Reordering of RLC data PDUs (only for UM and AM data transfer)

[0065] - Duplicate detection (only for UM and AM data transfer)

[0066] - Error detection function (Protocol error detection (only for AM data transfer))

[0067] - RLC SDU discard function (RLC SDU discard (only for UM and AM data transfer))

[0068] - RLC re-establishment function

[0069] MAC (215, 230) connects to multiple RLC layer devices configured in a single terminal, and multiplexes RLC PDUs into MAC PDUs and demultiplexes RLC PDUs from MAC PDUs. The main functions of MAC are summarized as follows.

[0070] - Mapping function (Mapping between logical channels and transport channels)

[0071] - Multiplexing and demultiplexing function (Multiplexing / demultiplexing of MAC SDUs belonging to one or different logical channels into / from transport blocks (TB) delivered to / from the physical layer on transport channels)

[0072] - Scheduling information reporting function

[0073] - HARQ (hybrid automatic repeat request) function (Error correction through HARQ)

[0074] - Priority handling between logical channels of one UE

[0075] - Priority handling between UEs by means of dynamic scheduling

[0076] - MBMS (multimedia broadcast multicast service) service identification function

[0077] - Transport format selection function

[0078] - Padding function

[0079] The physical layer (220, 225) performs an operation of channel coding and modulating upper layer data, converting it into OFDM symbols and transmitting it through a wireless channel, or demodulating and channel decoding OFDM symbols received through a wireless channel and transmitting them to a higher layer.

[0080] FIG. 3 is a diagram illustrating the structure of a wireless communication system according to an embodiment of the present disclosure.

[0081] Referring to FIG. 3, as illustrated, a wireless communication system (or NR system) includes a base station (New Radio Node B, hereinafter NR gNB or NR base station) (310) and an NR CN (305, New Radio Core Network). A user terminal (New Radio User Equipment, hereinafter NR UE or terminal (UE)) (315) connects to an external network through the NR gNB (310) and the NR CN (305).

[0082] In Fig. 3, the NR gNB (310) corresponds to the eNB (Evolved Node B) of the existing LTE system. The NR gNB is connected to the NR UE (315) via a wireless channel and can provide a communication service that is superior to the eNB (330). In a wireless communication system, all user traffic is serviced through a shared channel, so a device that collects status information such as the buffer status of UEs, available transmission power status, and channel status and performs scheduling is required, and the NR gNB (310) is in charge of this. One NR gNB typically controls multiple cells. The NR gNB (310) can have a bandwidth greater than the existing maximum bandwidth in order to implement ultra-high-speed data transmission compared to the current LTE, and uses orthogonal frequency division multiplexing (OFDM) as a wireless access technology, and additionally, beamforming technology can be used. In addition, an adaptive modulation and coding (AMC) method that determines a modulation scheme and a channel coding rate according to the channel status of the terminal (315) may be applied. The NR CN (305) performs functions such as mobility support, bearer setup, and QoS (Quality of Service) setup. The NR CN (305) is a device that is responsible for various control functions as well as mobility management functions for the terminal (315) and is connected to a number of base stations. In addition, the wireless communication system can also be linked with the existing LTE system, and the NR CN (305) is connected to the MME (325) through a network interface. The MME (325) is connected to the existing base station, the eNB (330).

[0083] FIG. 4 is a diagram showing a wireless protocol structure of a wireless communication system according to an embodiment of the present disclosure, and FIG. 4 is a diagram showing an example of a wireless protocol structure of a wireless communication system to which the present disclosure can be applied.

[0084] Referring to FIG. 4, the wireless protocol stack of the wireless communication system includes NR SDAP (service data adaptation protocol) (401, 445), NR PDCP (405, 440), NR RLC (410, 435), and NR MAC (415, 430) in the terminal and NR base station, respectively.

[0085] The main functions of NR SDAP (401, 445) may include at least some of the following functions:

[0086] - Transfer of user plane data

[0087] - Mapping function between QoS flow and data bearer for both DL (downlink) and UL (uplink)

[0088] - QoS flow ID marking function for uplink and downlink (marking QoS flow ID in both DL and UL packets)

[0089] - Ability to map reflective QoS flow to data bearer for the uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

[0090] For the above SDAP layer device, the terminal can be configured with an RRC (radio resource control) message for each PDCP layer device, each bearer, or each logical channel to use the header of the SDAP layer device or to use the function of the SDAP layer device, and when the SDAP header is configured, the terminal can be instructed to update or reset the mapping information for the QoS flow and data bearer of the uplink and downlink with a 1-bit indicator (NAS reflective QoS) for reflecting NAS (non-access stratum) QoS and a 1-bit indicator (AS reflective QoS) for reflecting AS QoS in the SDAP header. The SDAP header can include QoS flow ID information indicating QoS. The QoS information can be used as data processing priority, scheduling information, etc. to support a smooth service.

[0091] The main functions of NR PDCP (405, 440) may include at least some of the following functions:

[0092] - Header compression and decompression (ROHC only)

[0093] - User data transfer function

[0094] - In-sequence delivery of upper layer PDUs

[0095] - Out-of-sequence delivery of upper layer PDUs

[0096] - PDCP PDU reordering for reception

[0097] - Duplicate detection of lower layer SDUs

[0098] - Retransmission function (Retransmission of PDCP SDUs)

[0099] - Encryption and decryption functions (Ciphering and deciphering)

[0100] - Timer-based SDU discard in uplink.

[0101] The reordering function of the NR PDCP device above refers to a function of reordering PDCP PDUs received from a lower layer in order based on the PDCP SN (sequence number), and may include a function of transmitting data to an upper layer in the reordered order, or may include a function of transmitting data directly without considering the order, may include a function of recording lost PDCP PDUs by reordering the order, may include a function of reporting the status of lost PDCP PDUs to the transmitting side, and may include a function of requesting retransmission of lost PDCP PDUs.

[0102] The main functions of NR RLC (410, 435) may include at least some of the following functions:

[0103] - Data transfer function (Transfer of upper layer PDUs)

[0104] - In-sequence delivery of upper layer PDUs

[0105] - Out-of-sequence delivery of upper layer PDUs

[0106] - ARQ function (Error Correction through ARQ)

[0107] - Concatenation, segmentation and reassembly of RLC SDUs

[0108] - Re-segmentation of RLC data PDUs

[0109] - Reordering of RLC data PDUs

[0110] - Duplicate detection function

[0111] - Protocol error detection

[0112] - RLC SDU discard function

[0113] - RLC re-establishment function

[0114] The in-sequence delivery function of the NR RLC device above refers to the function of sequentially transmitting RLC SDUs received from a lower layer to an upper layer, and may include a function of reassembling and transmitting RLC SDUs when an RLC SDU is originally received divided into multiple RLC SDUs, may include a function of reordering received RLC PDUs based on RLC SN (sequence number) or PDCP SN (sequence number), may include a function of recording lost RLC PDUs by reordering the sequence, may include a function of reporting the status of lost RLC PDUs to the transmitting side, may include a function of requesting retransmission of lost RLC PDUs, may include a function of sequentially transmitting only RLC SDUs up to the lost RLC SDU to an upper layer when there is a lost RLC SDU, or may include a function of sequentially transmitting all RLC SDUs received before the timer starts when a predetermined timer expires even when there is a lost RLC SDU. Or, even if there are lost RLC SDUs, if a predetermined timer has expired, it may include a function to sequentially deliver all RLC SDUs received up to the upper layer. In addition, the RLC PDUs may be processed in the order they are received (in the order of arrival, regardless of the order of the sequence number) and delivered to the PDCP device out of sequence (out-of-sequence delivery). In the case of segments, the segments stored in the buffer or to be received later may be received, reconstructed into a single complete RLC PDU, processed, and then delivered to the PDCP device.The above NR RLC layer may not include a concatenation function, and the above function may be performed in the NR MAC layer or replaced with a multiplexing function of the NR MAC layer.

[0115] The out-of-sequence delivery function of the NR RLC device above refers to the function of directly delivering RLC SDUs received from a lower layer to an upper layer regardless of the order, and may include a function of reassembling and delivering RLC SDUs when an original RLC SDU is received divided into multiple RLC SDUs, and may include a function of storing the RLC SN or PDCP SN of received RLC PDUs and arranging the order to record lost RLC PDUs.

[0116] NR MAC (415, 430) can be connected to multiple NR RLC layer devices configured in one terminal, and the main function of NR MAC can include at least some of the following functions.

[0117] - Mapping function (Mapping between logical channels and transport channels)

[0118] - Multiplexing / demultiplexing of MAC SDUs

[0119] - Scheduling information reporting function

[0120] - HARQ function (Error correction through HARQ)

[0121] - Priority handling between logical channels of one UE

[0122] - Priority handling between UEs by means of dynamic scheduling

[0123] - MBMS service identification function

[0124] - Transport format selection function

[0125] - Padding function

[0126] The NR PHY layer (420, 425) can perform operations of channel coding and modulating upper layer data, converting it into OFDM symbols and transmitting it through a wireless channel, or demodulating and channel decoding OFDM symbols received through a wireless channel and transmitting them to a higher layer.

[0127] FIG. 5 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for periodically transmitting (required) system information in a wireless communication system according to an embodiment of the present disclosure.

[0128] A base station of a cell according to the present disclosure may periodically transmit (essential) system information, which means at least one of a Master Information Block (MIB) and a System Information Block 1 (SIB1). The essential system information includes configuration information required for a terminal to select or camp on a cell. Hereinafter, the essential system information may be simply referred to as system information.

[0129] The cell reselection evaluation procedure may refer to a procedure for determining whether to maintain the current serving cell or reselect a cell to a neighbor cell when the service quality of the serving cell on which the terminal is currently camping becomes lower than the service quality of the neighbor cell due to a predetermined reason or movement, while in the RRC idle state (RRC_IDLE) or RRC inactive state (RRC_INACTIVE).

[0130] In the case of handover, whether or not to perform a handover is determined by the network (AMF (Access and Mobility management Function) or source gNB), whereas in the case of cell reselection, a terminal in an RRC idle state or an RRC inactive state can determine whether or not to perform a cell reselection on its own based on a cell measurement value. The cell that the terminal reselects may refer to a cell using the same NR frequency (NR intra-frequency or serving NR frequency) as the serving cell on which the terminal is currently camping, a cell using a different NR frequency (NR inter-frequency) from the serving cell, or a cell in a frequency (inter-RAT frequency) using a different radio access technology (RAT). In the embodiments of the present disclosure, transmitting and receiving data between a terminal and an NR cell may refer to transmitting and receiving data between the terminal and a base station of the NR cell.

[0131] Referring to FIG. 5, a terminal (501) may establish an RRC connection with an NR cell (502) and be in an RRC connected state (RRC_CONNECTED) (503). In the embodiments of the present disclosure, the RRC connected state, the RRC idle state, and the RRC deactivated state may be referred to as an RRC connected mode, an RRC idle mode, and an RRC deactivated mode, respectively.

[0132] The NR cell (502) may transmit (504) an RRC connection release message (RRCRelease) to release the RRC connection with the terminal (501) in the RRC connection state. If the RRC connection release message includes, for example, suspension configuration information (suspendConfig), the terminal may transition (505) to an RRC inactive state (RRC_INACTIVE). If the RRC connection release message does not include the suspension configuration information, the terminal may transition (505) to an RRC idle state (RRC_IDLE). The RRC connection release message may include information indicating a priority for the terminal to perform cell reselection (e.g., cellReselectionPriorities). The cellReselectionPriorities may include at least one value among freqPriorityListEUTRA, freqPriorityListNR, and t320 defined in the 3GPP standard. The above terminal may operate the T320 timer defined in the 3GPP standard with the timer value of t320 included. Specifically, the configuration information included in the RRCRelease message may be as shown in [Table 1] below.

[0133] [Table 1]

[0134]

[0135]

[0136]

[0137]

[0138]

[0139] In step 513, a terminal (501) in an RRC idle state or an RRC inactive state can obtain essential system information from an NR cell (502). In the present disclosure, at least one of a Master Information Block (MIB) and a System Information Block 1 (SIB1) may be referred to as essential system information.

[0140] In step 515, the terminal (501) in the RRC idle state or RRC inactive state can perform a cell selection procedure based on the essential system information acquired in step 513. That is, the terminal can find an NR suitable cell belonging to the selected Public Land Mobile Network (PLMN) or Standalone Non-Public Network (SNPN) and camp on the cell. The cell on which the terminal (501) camps on can be referred to as a serving cell. In the present disclosure, a suitable cell can be defined if the conditions of [Table 2] below are satisfied based on the 3GPP standard document "TS 38.304: User Equipment (UE) procedures in Idle mode and RRC Inactive state."

[0141] [Table 2]

[0142]

[0143] For reference, the above terminal can be judged to fulfill the cell selection criteria if the following [Mathematical Formula 1] is satisfied.

[0144] [Mathematical Formula 1]

[0145] Srxlev > 0 AND Squal > 0

[0146] where

[0147] Srxlev = Q rxlevmeas - (Q rxlevmin + Q rxlevminoffset ) - P compensation - Qoffset temp,

[0148] Squal = Q qualmeas - (Q qualmin + Q qualminoffset ) - Qoffset temp

[0149] In the above [Mathematical Formula 1], the variables can be defined as shown in [Table 3] below.

[0150] [Table 3]

[0151]

[0152]

[0153] At step 520, the UE (501) in the RRC idle state or RRC deactivated state can obtain system information (e.g., SIB2, SIB3, SIB4, SIB5) including cell reselection information from the serving cell (502) to perform a cell reselection evaluation procedure. SIB2 may include at least one of information / parameters commonly applied to reselecting NR intra-frequency, NR inter-frequency, and inter-RAT frequency cells by the UE (501) in the RRC idle state or RRC deactivated state, and NR intra-frequency cell reselection information excluding information related to NR intra-frequency neighboring cells. For example, SIB2 may include one cell reselection priority setting information for a serving NR frequency (the frequency to which the currently camped-on cell belongs). The cell reselection priority setting information may indicate a priority value for cell reselection, for example, using cellReselectionPriority and cellReselectionSubPriority. Specifically, cellReselectionPriority can store an integer value (for example, an integer value from 0 to 7), and cellReselectionSubPriority can store a decimal value (for example, a decimal value from 0.2, 0.4, 0.6, 0.8). If both cellReselectionPriority and cellReselectionSubPriority are signaled, the terminal (501) can derive a cell reselection priority value by adding the two values. For reference, a larger cell reselection priority value indicates a higher priority. For example, cell reselection configuration information broadcast in SIB2 can include information as shown in [Table 4] below.

[0154] [Table 4]

[0155]

[0156]

[0157]

[0158] SIB3 may include neighboring cell information / parameters for a UE in an RRC idle state or an RRC inactive state to reselect an NR intra-frequency cell. For example, SIB3 may broadcast at least one of an NR intra-frequency cell list for reselecting an NR intra-frequency cell (intraFreqNeighCellList), a list of cells for which NR intra-frequency cell reselection is allowed (intraFreqAllowedCellList), and a list of cells for which NR intra-frequency cell reselection is not allowed (intraFreqExcludedCellList). For example, SIB3 may include information as shown in [Table 5] below.

[0159] [Table 5]

[0160]

[0161]

[0162] SIB4 may include information / parameters for a UE in RRC idle or RRC inactive state to reselect an NR inter-frequency cell. For example, SIB4 may broadcast one or more NR inter-frequencies, and may broadcast one cell reselection priority setting information for each NR inter-frequency. The cell reselection priority setting information for each NR inter-frequency means the above-described contents (e.g., cellReselectionPriority and / or cellReselectionSubPriority mapped to each NR inter-frequency), but has the characteristic that one cell reselection priority setting information for each inter-frequency is optionally broadcast. For example, SIB4 may include the information in [Table 6] below.

[0163] [Table 6]

[0164]

[0165]

[0166]

[0167]

[0168] SIB5 may include information / parameters for a UE in RRC idle or RRC inactive state to reselect an inter-RAT frequency cell. For example, SIB5 may be broadcast including one or more EUTRA frequencies, and may include one cell reselection priority setting information for each EUTRA frequency. The cell reselection priority setting information for each EUTRA frequency refers to the above-described contents (e.g., cellReselectionPriority and / or cellReselectionSubPriority mapped to each EUTRA frequency), but one cell reselection priority setting information for each EUTRA frequency may optionally be included and broadcast. For example, SIB5 may include the information in [Table 7] below.

[0169] [Table 7]

[0170]

[0171]

[0172] A terminal in an RRC idle state or an RRC inactive state can perform a cell reselection evaluation process. The cell reselection evaluation process may refer to a series of processes for determining reselection priorities, performing frequency measurements by applying measurement rules for cell reselection, and evaluating cell reselection criteria to reselect a cell.

[0173] In step 525, the terminal (501) in the RRC idle state or RRC inactive state can determine the reselection priority based on the RRC release message received in step 504 or the system information received in step 520. If the RRC connection release message received in step 504 includes cellReselectionPriorities and there is no t320 timer value in cellReselectionPriorities or the t320 timer value is set and the T320 timer is running, the terminal (501) can determine the reselection priority according to the RRC connection release message. That is, if celllReselectionPriorities included in the RRC connection release message can be applied, the terminal (501) can determine the reselection priority according to the RRC connection release message. If the RRC connection release message does not include cellReselectionPriorities or cellReselectionPriorities is released, the terminal (501) can determine the reselection priority based on the system information received in step 520. The terminal (501) according to the present disclosure can determine, based on the cell reselection priority value mapped to the NR frequency to which the serving cell currently camped-on belongs, whether the cell reselection priority for each NR inter-frequency or inter-RAT frequency has the same cell reselection priority as the NR frequency to which the serving cell belongs, has a cell reselection priority higher than the NR frequency to which the serving cell belongs, or has a cell reselection priority lower than the NR frequency to which the serving cell belongs.For example, in step 520, if the terminal (501) has a cell reselection priority value mapped to the NR frequency to which the serving cell currently camped on belongs in the acquired system information as 3, a cell reselection priority value of inter NR frequency 1 as 2, a cell reselection priority value of inter NR frequency 2 as 3, a cell reselection priority value of inter NR frequency 3 as 4, and a cell reselection priority value of EUTRA frequency 1 as 2, the terminal (501) may determine inter NR frequency 1 and EUTRA frequency 1 as having lower reselection priorities, determine the cell reselection priorities of inter NR frequency 2 as being equal (equal reselection priority), and determine the cell reselection priority of inter NR frequency 3 as having higher reselection priorities.

[0174] In step 530, a terminal (501) in an RRC idle state or an RRC inactive state may perform frequency measurement for cell reselection. At this time, the terminal (501) may perform frequency measurement using the following measurement rule according to the cell reselection priority determined in step 525 to minimize battery consumption.

[0175] - The terminal (501) may not perform NR intra-frequency measurement if the following condition 1 is satisfied. Otherwise (for example, if the following condition 1 is not satisfied), the terminal (501) performs NR intra-frequency measurement:

[0176] - Condition 1: The reception level (Srxlev) of the serving cell is greater than the SIntraSearchP threshold and the reception quality (Squal) of the serving cell is greater than the SIntraSearchQ threshold (Serving cell fulfils Srxlev > SIntraSearchP and Squal > SIntraSearchQ).

[0177] - The terminal (501) can perform measurements according to the 3GPP TS 38.133 standard for an NR inter-frequency or inter-RAT frequency having a higher reselection priority than the NR frequency of the current serving cell.

[0178] - For an NR inter-frequency having a reselection priority lower than or equal to the NR frequency of the current serving cell and an inter-RAT frequency having a reselection priority lower than the NR frequency of the current serving cell, the terminal (501) may not perform measurement if the following condition 2 is satisfied. Otherwise, (for example, if the following condition 2 is not satisfied), the terminal (501) measures cells in an NR inter-frequency having a reselection priority lower than or equal to the NR frequency or measures cells in an inter-RAT frequency having a reselection priority lower than the NR frequency:

[0179] - Condition 2: The reception level (Srxlev) of the serving cell is greater than the SnonIntraSearchP threshold and the reception quality (Squal) of the serving cell is greater than the SnonIntraSearchQ threshold (Serving cell fulfils Srxlev > SnonIntraSearchP and Squal > SnonIntraSearchQ).

[0180] For reference, the aforementioned threshold values ​​(SintraSearchP, SintraSearchQ, SnonIntraSearchP SnonintraSearchQ) may be included in the system information acquired by the terminal (501) in step 520.

[0181] In step 535, the terminal (501) in the RRC idle state or RRC deactivation state may decide to reselect a cell that satisfies the cell reselection criteria based on the measurement value performed in step 530. Different criteria may be applied to the cell reselection criteria depending on the cell reselection priority. If multiple cells that satisfy the cell reselection criteria have different cell reselection priorities, reselecting a frequency / RAT cell with a higher cell reselection priority is given priority over reselecting a frequency / RAT cell with a lower priority. Specifically, the operation of the terminal (501) with respect to the reselection criteria of an inter-frequency / inter-RAT cell having a higher priority than the frequency of the current serving cell is the same as the first to fifth operations below.

[0182] - First movement:

[0183] - If SIB2 includes a threshold for threshServingLowQ and is broadcast, and if, for example, 1 second has passed since the terminal (501) camped on the current serving cell, and if the signal quality (Squal) of the inter-frequency / inter-RAT cell is greater than the threshold ThreshX,HighQ during a specific time interval TreselectionRAT (Squal > ThreshX,HighQ during a time interval TreselectionRAT), the terminal performs reselection to the inter-frequency / inter-RAT cell.

[0184] - Second movement:

[0185] - If the terminal (501) above cannot perform the first operation, it performs the second operation.

[0186] - If, for example, 1 second has passed since the terminal camped on the current serving cell and the reception level (Srxlev) of the inter-frequency / inter-RAT cell is greater than the threshold ThreshX,HighP during a specific time interval TreselectionRAT (Srxlev > ThreshX,HighP during a time interval Treselection-RAT-), the terminal performs reselection to the inter-frequency / inter-RAT cell.

[0187] Here, the terminal (501) is configured to measure the signal quality (Squal), reception level (Srxlev), and threshold values ​​(Threh) of the inter-frequency cell. X, HighQ , Thresh X, HighP ), Treselection RAT The values ​​perform the first or second operation based on the information contained in SIB4 broadcast from the serving cell, and the signal quality (Squal), reception level (Srxlev), and threshold (Thresh) of the inter-RAT cell. X,HighQ, Thresh X, HighP), Treselection RAT The terminal (501) performs the first or second operation based on the information contained in SIB5 broadcast from the serving cell. For example, SIB4 includes Q qualmin value or Q rxlevmin The values ​​are included, and based on this, the terminal (501) derives the signal quality (Squal) or reception level (Srxlev) of the inter-frequency cell. If there are multiple cells in the NR frequency that satisfy the high cell reselection priority, the terminal (501) can reselect the highest-ranked cell among the cells that satisfy the reselection criteria of the intra-frequency / inter-frequency cell that has the same priority as the frequency of the current serving cell described below.

[0188] In addition, the operation of the terminal (501) for the reselection criteria of the intra-frequency / inter-frequency cell having the same priority as the frequency of the current serving cell is as follows.

[0189] - Third movement:

[0190] - If the signal quality (Squal) and reception level (Srxlev) of an intra-frequency / inter-frequency cell are greater than 0, the UE (501) derives a rank for each cell based on the measured value (RSRP) (The UE shall perform ranking of all cells that fulfills the cell selection criterion S). The ranks of the serving cell and neighboring cells are each calculated using the following mathematical expression 2.

[0191] [Equation 2]

[0192] R s = Q meas,s + Q hyst - Qoffsettemp

[0193] R n = Q meas,n - Qoffset - Qoffset temp

[0194] - Here, Qmeas,s is the RSRP measurement value of the serving cell, Qmeas,n is the RSRP measurement value of the neighboring cell, Qhyst is the hysteresis value of the serving cell, and Qoffset is the offset between the serving cell and the neighboring cells. The Qhyst value is included in SIB2, and the value is commonly used for intra-frequency / inter-frequency cell reselection. In case of intra-frequency cell reselection, Qoffset is signaled per cell, applied only to the indicated cell, and included in SIB3. In case of inter-frequency cell reselection, Qoffset is signaled per cell, applied only to the indicated cell, and included in SIB4. When the Rank of the neighboring cell obtained from the above mathematical expression 2 is greater than the Rank of the serving cell (Rn > Rs), the terminal reselects the cell as the optimal cell among the neighboring cells.

[0195] - Qoffset here - temp- - may mean connEstFailOffset included in ConnEstFailureControld broadcast in SIB1 as an offset temporarily applied to the cell, and may be applied when an RRC connection fails (e.g., when the T300 timer expires).

[0196] Additionally, the operation of the terminal (501) for the reselection criteria of an inter-frequency / inter-RAT cell having a lower priority than the frequency of the current serving cell is as follows.

[0197] - 4th movement:

[0198] - If SIB2 is broadcast with a threshold for threshServingLowQ and 1 second has passed since the terminal (501) camped on the current serving cell, if the signal quality (Sqaul) of the current serving cell is lower than the threshold ThreshServing, LowQ (Squal < ThreshServing, LowQ) and the signal quality (Squal) of the inter-frequency / inter-RAT cell is higher than the threshold ThreshX, LowQ- during a specific time TreselectionRAT (Squal > ThreshX,LowQ during a time interval TreselectionRAT), the terminal (501) performs reselection to the inter-frequency / inter-RAT cell.

[0199] - Movement 5:

[0200] - If the terminal (501) above cannot perform the fourth operation, it performs the fifth operation.

[0201] - If 1 second has passed since the terminal (501) camped on the current serving cell, and the reception level (Srxlev) of the current serving cell is less than the threshold ThreshServing, LowP (Srxlev < ThreshServing, LowP) and the reception level (Srxlev) of the inter-frequency / inter-RAT cell is greater than the threshold ThreshX, LowQ- during a specific time interval TreselectionRAT (Srxlev > ThreshX,LowP during a time interval TreselectionRAT), the terminal performs reselection to the inter-frequency / inter-RAT cell.

[0202] Here, the fourth or fifth operation for the inter-frequency cell of the terminal (501) is the thresholds (ThreshServing, LowQ, ThreshServing, LowP) included in SIB2 broadcasted in the serving cell and the signal quality (Squal), reception level (Srxlev), and thresholds (Threh) of the inter-frequency cell included in SIB4 broadcasted in the serving cell. X, LowQ, Thresh X, LowP ), Treselection RAT , and the fourth or fifth operation for the inter-RAT cell of the terminal (501) is performed based on the thresholds (ThreshServing, LowQ, ThreshServing, LowP) included in SIB2 broadcasted in the serving cell and the signal quality (Squal), reception level (Srxlev), and thresholds (Thresh) of the inter-RAT cell included in SIB5 broadcasted in the serving cell. X,LowQ , Thresh X, LowP ), Treselection RAT It is performed based on. For example, in SIB4, Q qualmin value or Q rxlevmin The values ​​are included, and the terminal derives the signal quality (Squal) or reception level (Srxlev) of the inter-frequency cell based on these. If there are multiple cells in the NR frequency that satisfy the high cell reselection priority, the terminal (501) can reselect the highest-ranked cell among the cells that satisfy the reselection criteria of the intra-frequency / inter-frequency cell that has the same priority as the frequency of the current serving cell described below.

[0203] At step 540, the terminal (501) in the RRC idle state or RRC inactive state receives system information (e.g., MIB or SIB1) broadcast from the candidate target cell before finally reselecting the candidate target cell, and determines based on the received system information whether the reception level (Srxlev) and reception quality (Squal) of the candidate target cell satisfy the cell selection criterion called S-criterion (see the above mathematical expression 1) (Srxlev > 0 AND Squal > 0). If the above mathematical expression 1 is satisfied and the candidate target cell is suitable, the terminal (501) can reselect the candidate target cell.

[0204] FIG. 6 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for transmitting System Information Block 1 (SIB1) on-demand in a wireless communication system according to an embodiment of the present disclosure.

[0205] A given cell according to the present disclosure may periodically transmit essential system information, which means at least one of a Master Information Block (MIB) and a System Information Block 1 (SIB1). The (essential) system information includes configuration information required for a terminal to select or camp on a cell. In the embodiments of the present disclosure below, the essential system information may be simply referred to as system information. Additionally, a given cell according to the present disclosure may transmit the MIB periodically, but may transmit the SIB1 in an on-demand manner, unlike the above-described embodiment (FIG. 5). This is because network energy can be saved by transmitting the SIB1 when a terminal requests it.

[0206] In the embodiments of the present disclosure, the terminal transmitting and receiving data with an NR cell may mean that the terminal transmits and receives data with a base station of the NR cell. In addition, in the embodiments of the present disclosure, the NR cell from which the terminal receives an RRC connection release message may be referred to as a first cell (or a first base station), and the NR cell from which the terminal receives an on-demand SIB1 may be referred to as a second cell (or a second base station).

[0207] Referring to FIG. 6, the terminal (601) may be in an RRC connected state (RRC_CONNECTED) by establishing an RRC connection with an NR cell (605) (610).

[0208] At step 615, the terminal (601) may transmit terminal capability information (UECapabilityInformation) to the NR cell (605). The terminal capability information may include at least one of the following capability information.

[0209] - Capability information to transmit a wake-up signal (WUS), which is a signal to request a cell transmitting SIB1 on-demand to transmit SIB1.

[0210] - Ability to receive SIB1 per cell or per cell list via RRC disconnection message

[0211] - Ability to receive some SIB1 information per cell or per cell list via RRC disconnection message.

[0212] In step 620, the NR cell (605) may transmit an RRC connection release message (RRCRelease) to release the RRC connection with the terminal (601) in the RRC connection state. The information included in the RRC connection release message may follow at least the aforementioned embodiment (Fig. 5). Additionally, the RRC connection release message may include at least one of the following information 1-1) to 1-4).

[0213] 1-1) SIB1 per cell:

[0214] - A cell may be expressed by a physical cell identity (PCI) or by a PCI and a carrier frequency.

[0215] - In general, a cell can transmit SIB1 on-demand, and in the present disclosure, by providing SIB1 (or at least a part of SIB1) to the terminal (601) in advance, the process of requesting the terminal (601) to transmit SIB1 to the cell (i.e., on-demand SIB1 request) is omitted, and the terminal (601) can select or reselect the cell based on the SIB1 received in advance.

[0216] 1-2) SIB1 per cell list:

[0217] - If one or more cells apply the same SIB1, the cell list and the SIB1 applied thereto may be included in the RRC connection release message.

[0218] 1-3) SIB1 by frequency:

[0219] - If all cells in a frequency apply the same SIB1, the frequency and the SIB1 applied thereto may be included in the RRC connection release message. Here, the frequency means the Absolute Radio-Frequency Channel Number (AFRCN) (or carrier frequency).

[0220] 1-4) Some essential information in SIB1 per cell or cell list or per frequency:

[0221] - Some of the parameters included in SIB1 may be referred to as some essential information. For example, the above-mentioned some essential information may include at least one of the information a) to c) below.

[0222] a) At least one of the parameters (e.g., parameters in cellSelectionInfo) required for the terminal (601) to determine the S criterion according to the above-described embodiment may be the essential information in SIB1.

[0223] b) At least one of the parameters (e.g., parameters in cellSelectionInfo and cellAccessRelatedInfo) required for the terminal (601) to determine a suitable cell according to the above-described embodiment may be the above-described essential information in SIB1.

[0224] c) At least one of the parameters required for the terminal (601) to access a cell (e.g., cellSelectionInfo, cellAccessRelatedInfo, onnEstFailureControl, servingCellConfigCommon, ue-TimersAndConstants, uac-BarringInfo, useFullResumeId) may be some essential information in SIB1.

[0225] For example, SIB1 may include at least one of the information in [Table 8] below.

[0226] [Table 8]

[0227]

[0228]

[0229]

[0230]

[0231]

[0232]

[0233] The terminal (601) in the RRC connection state may apply / confirm the information included in the RRC connection release message, and then, as in the embodiment described above, the terminal (601) may transition from the RRC connection state to the RRC idle state (RRC_IDLE) or the RRC inactive state (RRC_INACTIVE) at step 625.

[0234] At step 630, the terminal (601) in the RRC idle state or RRC inactive state can obtain MIB and SIB1, which are essential system information, from the NR cell (605).

[0235] In step 635, the terminal (601) may perform a cell selection procedure based on step 630. The basic operation of the cell selection procedure may follow the embodiment of FIG. 5 described above.

[0236] At step 640, the terminal (601) can obtain system information (e.g., SIB2, SIB3, SIB4, SIB5, new SIB) including cell reselection information from the serving cell (605) to perform a cell reselection evaluation procedure. This can follow the embodiment of FIG. 5 described above. Additionally, the serving cell (605) according to the present disclosure can broadcast system information including WUS configuration information. The serving cell (605) can include WUS configuration information in at least one of SIB2, SIB3, SIB4, and SIB5, or can transmit WUS configuration information to the terminal (601) through new system information (new SIB). Specifically, the WUS configuration information can be included in the system information and provided to the terminal using one of the following methods 1 and 2.

[0237] - Method 1: WUS configuration per frequency:

[0238] - The serving cell (605) can provide the terminal (601) with WUS configuration information for the serving frequency (NR intra-frequency) through SIB2 or SIB3, and with WUS configuration information for each adjacent NR frequency (NR inter-frequency) through SIB4. Of course, by defining new system information (new SIB), the serving cell (605) can also provide the terminal (601) with WUS configuration information for each frequency through the new system information.

[0239] - Method 2: WUS configuration per cell (or per cell list) per frequency:

[0240] - The serving cell (605) can provide the terminal (601) with WUS configuration information per cell or per cell list in the serving frequency (NR intra-frequency) through SIB2 or SIB3, and with WUS configuration information per cell per adjacent NR frequency (NR inter-frequency) or per cell list per NR inter-frequency through SIB4. Here, the WUS configuration information per cell list may mean that cells composed of one or more cells share WUS configuration information. Of course, by defining new system information (new SIB), the serving cell (605) can also provide the terminal (601) with WUS configuration information per cell (or per cell list) frequency through the new system information.

[0241] The above WUS configuration information may include configuration information required for the terminal (601) to transmit a random access preamble as random access parameters. For example, the WUS configuration information may include at least one of a random access preamble index (or index range), information on the number of SSBs (synchronization signal / PBCH (physical broadcast channel) blocks) per PRACH (physical random access channel) Occasion, an RSRP (reference signal received power) threshold (rsrp-ThresholdSSB), and PRACH Occasion location information (information on which a preamble, which is a physical signal specifically designed for uplink synchronization, can be transmitted).

[0242] At step 645, the terminal (601) may determine a reselection priority for cell reselection. This may follow the embodiment described above (Fig. 5).

[0243] At step 647, the cell (607) transmitting SIB1 in an on-demand manner can transmit SSB, which is a synchronization signal.

[0244] At step 650, the terminal (601) may perform frequency measurement for cell reselection. This may follow the embodiment described above (Fig. 5).

[0245] In step 655, the terminal (601) may determine a candidate target cell that satisfies the cell reselection criteria based on the measurement values ​​performed in step 650. This may follow the aforementioned embodiment (Fig. 5). Accordingly, the terminal according to the present disclosure may determine the final candidate target cell as the NR cell (607). That is, the NR cell (607) may be the best cell or the highest-ranked cell for the terminal (601).

[0246] At step 660, the terminal (601) can determine / confirm whether it has received SIB1 or some essential information in SIB1, which is configuration information required to reselect the NR cell (607), through the RRC connection release message at step 620. For reference, the NR cell (607) may be a cell that transmits SIB1 on-demand.

[0247] In step 665, the terminal (601) determines whether the reception level (Srxlev) and reception quality (Squal) of the candidate target cell (607) satisfy a cell selection criterion (Srxlev > 0 AND Squal > 0) called S-criterion (see the embodiment of FIG. 5 described above) based on the MIB received from the candidate target cell (607) and the SIB1 information (or some essential information in SIB1) about the cell (607) received through the RRC disconnection message in step 620. If the S-criterion is satisfied and the candidate target cell (607) is suitable, the terminal (601) can reselect the candidate target cell (607). As an optional embodiment, the terminal (601) may transmit a WUS to the candidate target cell (607) to obtain SIB1 from the candidate target cell (607) in order to connect to the candidate target cell (607) (i.e., to transition to an RRC connection state).

[0248] As in the embodiment of FIG. 6, the terminal (601) can receive configuration information for selecting or reselecting a cell that transmits SIB1 on-demand via an RRC connection release message. Accordingly, the terminal can select or reselect a cell that transmits SIB1 on-demand even if the cell does not transmit WUS to the cell. As an optional embodiment, the terminal (601) can also delete SIB1 (or some essential information in SIB1) per cell (or per cell list or per frequency) received via the RRC connection release message if at least one of the following conditions 2-1) to 2-4) is satisfied.

[0249] 2-1) If the selected or reselected cell is not the cell set in the RRC connection release message.

[0250] 2-2) When the RRC status of the terminal changes or transitions to the RRC connection status

[0251] 2-3) When Inter-RAT cell selection or reselection occurs

[0252] 2-4) If a Public Land Mobile Network (PLMN) or Standalone Non-Public Network (SNPN) is selected due to a Non-Access Stratum (NAS) request.

[0253] Of course, the terminal (601) may maintain the SIB1 (or some essential information in the SIB1) per cell (or per cell list or per frequency) received through the RRC connection release message even if at least one of the conditions 2-1) to 2-4) is satisfied. This is because, when maintained, the terminal (601) can select or reselect the cell transmitting the SIB1 on-demand even if it does not transmit a WUS to the cell.

[0254] FIG. 7 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for transmitting System Information Block 1 (SIB1) on-demand in a wireless communication system according to an embodiment of the present disclosure.

[0255] A given cell according to the present disclosure may periodically transmit essential system information, which means at least one of a Master Information Block (MIB) and a System Information Block 1 (SIB1). The essential system information includes configuration information required for a terminal to select or camp on a cell. Additionally, a given cell according to the present disclosure may transmit the MIB periodically, but may transmit the SIB1 on-demand, unlike the above-described embodiment (Fig. 5). This is because network energy can be saved by transmitting the SIB1 when a terminal requests it.

[0256] Referring to FIG. 7, the terminal (701) may be in an RRC connected state (RRC_CONNECTED) by establishing an RRC connection with an NR cell (705) (710).

[0257] At step 715, the terminal (701) may transmit terminal capability information (UECapabilityInformation) to the NR cell (705). The terminal capability information may include at least one of the following capability information.

[0258] - Capability information to transmit a wake-up signal (WUS), which is a signal to request a cell transmitting SIB1 on-demand to transmit SIB1.

[0259] - Ability to receive SIB1 per cell or per cell list via RRC disconnection message

[0260] - Ability to receive some SIB1 information per cell or per cell list via RRC disconnection message.

[0261] In step 720, the NR cell (705) may transmit an RRC connection release message (RRCRelease) to release the RRC connection with the terminal (701) in the RRC connection state. The RRC connection release message may include at least one of the information of 1-1) to 1-4) described in the embodiment of FIG. 6 and information on the next new timer value.

[0262] - New timer value:

[0263] The new timer value may refer to a timer value that controls until when the terminal applies (i.e., the applicable period) some essential information in the per-cell (or per-cell list or per-frequency) SIB1 or the per-cell (or per-cell list or per-frequency) SIB1 received in the RRC connection release message. For example, the terminal that has received the new timer value may start the new timer with the timer value after receiving the RRC connection release message. While the new timer is running, the terminal (701) may use some essential information in the per-cell (or per-cell list or per-frequency) SIB1 or the per-cell (or per-cell list or per-frequency) SIB1 received through the RRC connection release message. When the timer is stopped or expired, the terminal (701) may release some essential information in the per-cell (or per-cell list or per-frequency) SIB1 or the per-cell (or per-cell list or per-frequency) SIB1 received through the RRC connection release message.

[0264] The terminal (701) in the RRC connection state may apply / confirm the information included in the RRC connection release message, and then, as in the embodiment described above, the terminal (701) may transition from the RRC connection state to the RRC idle state (RRC_IDLE) or the RRC inactive state (RRC_INACTIVE) at step 725.

[0265] At step 730, the terminal (701) in the RRC idle state or RRC inactive state can obtain essential system information, MIB and SIB1, from the NR cell (705).

[0266] In step 735, the terminal (701) may perform a cell selection procedure based on step 730. The basic operation of the cell selection procedure may follow the embodiment of FIG. 5 described above.

[0267] At step 740, the terminal (701) may obtain system information (e.g., SIB2, SIB3, SIB4, SIB5, new SIB) including cell reselection information from the serving cell (705) to perform a cell reselection evaluation procedure. This may follow at least one of the embodiments of FIGS. 5 and 6 described above.

[0268] At step 745, the terminal (701) may determine a reselection priority for cell reselection. This may follow the embodiment described above (Fig. 5).

[0269] At step 747, a cell (707) transmitting SIB1 in an on-demand manner can transmit a synchronization signal, SSB (Synchronization Signal / PBCH block, hereinafter referred to as SSB).

[0270] At step 750, the terminal (701) may perform frequency measurement for cell reselection. This may follow the embodiment described above (Fig. 5).

[0271] In step 755, the terminal (701) may determine a candidate target cell that satisfies the cell reselection criteria based on the measurement values ​​performed in step 750. This may follow the aforementioned embodiment (Fig. 5). Accordingly, the terminal according to the present disclosure may determine the final candidate target cell as the NR cell (707). That is, the NR cell (707) may be the best cell or the highest-ranked cell for the terminal (701).

[0272] At step 760, the terminal (701) can determine / confirm whether the new timer driven at step 720 has been started and whether SIB1 or some essential information included in SIB1, which is the configuration information required to reselect the NR cell (707), has been received through an RRC connection release message at step 720. For reference, the NR cell (707) may be a cell that transmits SIB1 on-demand.

[0273] In step 765, the terminal (701) determines whether the reception level (Srxlev) and reception quality (Squal) of the candidate target cell (707) satisfy a cell selection criterion (Srxlev > 0 AND Squal > 0) called S-criterion (see the embodiment of FIG. 5 described above) based on the MIB received from the candidate target cell (707) and the SIB1 information (or some essential information in SIB1) about the cell (707) received through the RRC disconnection message in step 720. If the S-criterion is satisfied and the candidate target cell (707) is suitable, the terminal (701) can reselect the candidate target cell (707). As an optional embodiment, the terminal (701) may transmit a WUS to the candidate target cell (607) to obtain SIB1 from the candidate target cell (607) in order to connect to the candidate target cell (707) (i.e., to transition to an RRC connection state).

[0274] As in the embodiment of Fig. 7, the terminal (701) can receive configuration information for selecting or reselecting a cell transmitting SIB1 on-demand via an RRC connection release message. The effective application period for the configuration information may be while the new timer is running. Therefore, the terminal can select or reselect a cell transmitting SIB1 on-demand even if it does not transmit WUS to the cell. As an optional embodiment, the terminal (701) can stop the running new timer if at least one of the following conditions 3-1) to 3-5) is satisfied.

[0275] 3-1) If the selected or reselected cell is not the cell set in the RRC connection release message.

[0276] 3-2) When the RRC state changes or transitions to the RRC connected state

[0277] 3-3) When Inter-RAT cell selection or reselection occurs

[0278] 3-4) When selecting Public Land Mobile Network (PLMN) or Standalone Non-Public Network (SNPN) due to Non-Access Stratum (NAS) request

[0279] 3-5) If the received RRC connection release message does not have the SIB1 (or some essential information in SIB1) set for each cell (or per cell list or per frequency) or a new timer value is not set.

[0280] Of course, the terminal (701) may continue to run the running new timer even if at least one of the conditions 3-1) to 3-5) is satisfied. This is because the terminal (701) can select or reselect a cell transmitting SIB1 on-demand even if it does not transmit WUS to the cell. As an optional embodiment, the terminal (701) may stop the running new timer or, when the running new timer expires, delete the SIB1 (or some essential information in the SIB1) received per cell (or per cell list or per frequency) via an RRC connection release message.

[0281] FIG. 8 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for transmitting System Information Block 1 (SIB1) on-demand in a wireless communication system according to an embodiment of the present disclosure.

[0282] A given cell according to the present disclosure may periodically transmit essential system information, which means at least one of a Master Information Block (MIB) and a System Information Block 1 (SIB1). The essential system information includes configuration information required for a terminal to select or camp on a cell. Additionally, a given cell according to the present disclosure may transmit the MIB periodically, but may transmit the SIB1 on-demand, unlike the above-described embodiment (Fig. 5). This is because network energy can be saved by transmitting the SIB1 when a terminal requests it.

[0283] Referring to FIG. 8, at step 810, the terminal (801) may establish an RRC connection with an NR cell (805) and be in an RRC connected state (RRC_CONNECTED).

[0284] At step 815, the terminal (801) may transmit terminal capability information (UECapabilityInformation) to the NR cell (805). The terminal capability information may include at least one of the following capability information.

[0285] - Capability information to transmit a wake-up signal (WUS), which is a signal to request a cell transmitting SIB1 on-demand to transmit SIB1.

[0286] - Ability to receive SIB1 per cell or per cell list via RRC disconnection message

[0287] - Ability to receive some SIB1 information per cell or per cell list via RRC disconnection message.

[0288] Additionally, the terminal capability information may include capability information that can be used by applying configuration information for a wake-up signal (hereinafter referred to as WUS), which is a signal for requesting a cell that transmits SIB1 on-demand via an RRC connection release message (and / or system information) to transmit SIB1.

[0289] In step 820, the NR cell (805) may transmit an RRC connection release message (RRCRelease) to release the RRC connection with the terminal (801) in the RRC connection state. The RRC connection release message may include at least one of the information of 1-1) to 1-4) described in the embodiment of FIG. 6, the new timer value in the embodiment of FIG. 7, and the information of 4-1) and 4-2).

[0290] 4-1) An indicator indicating whether the terminal (801) can transmit WUS.

[0291] 4-2) Setting information required when the above terminal (801) transmits WUS:

[0292] - The above setting information can be set by frequency, by cell per frequency, or by cell list per frequency.

[0293] - The above configuration information may indicate one or more random access preambles. For example, it may refer to a preamble indicating the first message (Msg1) transmitted by the terminal to the base station during a random access procedure.

[0294] - The above configuration information may indicate one or more random access opportunities (PRACH occasions) during which the terminal may transmit a preamble. For example, a RACH occasion may indicate the frequency / time at which the preamble will be transmitted during a random access procedure.

[0295] The terminal (801) in the RRC connection state may apply / confirm the information included in the RRC connection release message, and then, as in the embodiment described above, the terminal (801) may transition from the RRC connection state to the RRC idle state (RRC_IDLE) or the RRC inactive state (RRC_INACTIVE) at step 825.

[0296] At step 830, a terminal (801) in an RRC idle state or an RRC inactive state can obtain essential system information, MIB and SIB1, from an NR cell (805).

[0297] In step 835, the terminal (801) may perform a cell selection procedure based on step 830. The basic operation of the cell selection procedure may follow the embodiment of FIG. 5 described above.

[0298] At step 840, the terminal (801) may obtain system information (e.g., SIB2, SIB3, SIB4, SIB5, new SIB) including cell reselection information from the serving cell (805) to perform a cell reselection evaluation procedure. This may follow at least one of the embodiments of FIGS. 5 to 7 described above.

[0299] At step 845, the terminal (801) may determine a reselection priority for cell reselection. This may follow the embodiment described above (Fig. 5).

[0300] At step 847, a cell (807) transmitting SIB1 in an on-demand manner can transmit a synchronization signal, SSB (Synchronization Signal / PBCH block, hereinafter referred to as SSB).

[0301] At step 850, the terminal (801) may perform frequency measurement for cell reselection. This may follow the embodiment described above (Fig. 5).

[0302] In step 855, the terminal (801) may determine a candidate target cell that satisfies the cell reselection criteria based on the measurement values ​​performed in step 850. This may follow the aforementioned embodiment (Fig. 5). Accordingly, the terminal according to the present disclosure may determine the final candidate target cell as the NR cell (807). That is, the NR cell (807) may be the best cell or the highest-ranked cell for the terminal (801).

[0303] At step 860, the terminal (801) can confirm that the NR cell (807) transmits SIB1 on-demand. For example, the terminal can confirm whether the NR cell (807) transmits SIB1 on-demand through an RRC connection release message (step 820) or through system information (step 840). In the following embodiment, it is assumed that the candidate target NR cell (807) can transmit SIB1 on-demand.

[0304] At step 865, the terminal (801) may transmit a WUS to the candidate target NR cell (807) in order to receive SIB1 from the candidate target NR cell (807). For example, if the WUS configuration information for the candidate target NR cell (807) can be applied through the RRC connection release message (step 820), the terminal (801) may transmit a WUS to the candidate target NR cell (807) in order to receive SIB1 from the candidate target NR cell (807) based on the WUS configuration information. In an optional embodiment, if the terminal (801) cannot apply the WUS configuration information for the candidate target NR cell (807) through the RRC connection release message and can apply the WUS configuration information for the candidate target NR cell (807) through the system information (step 840), the terminal (801) may transmit a WUS to the candidate target NR cell (807) to receive SIB1 from the candidate target NR cell (807) based on the WUS configuration information received through the system information (step 840). That is, the terminal (801) may give priority to the WUS configuration information set in the RRC connection release message over the WUS configuration information broadcast in the system information.

[0305] At step 870, the NR cell (807) can transmit SIB1 and the terminal (801) can receive it. The terminal (801) can receive the MIB transmitted by the NR cell (807) at step 870 or at a previous step (e.g., step 847, step 855, or step 860).

[0306] At step 875, the terminal (801) determines whether the reception level (Srxlev) and reception quality (Squal) of the candidate target NR cell (807) satisfy a cell selection criterion (Srxlev > 0 AND Squal > 0) called S-criterion (see Equation 1, the embodiment of FIG. 5 described above) based on the essential system information (MIB and / or SIB1) received from the candidate target NR cell (807). If the S-criterion is satisfied and the candidate target NR cell (807) is suitable, the terminal (801) can reselect the candidate target NR cell (807).

[0307] The terminal (801) according to the present disclosure can transmit WUS to a candidate target NR cell (807) to receive SIB1 from the candidate target NR cell (807) transmitting SIB1 on-demand. The configuration information for transmitting the WUS by the terminal (801) can be obtained through an RRC connection release message or through system information. As an optional embodiment, the terminal (801) can delete / ignore the WUS configuration information received through the RRC connection release message if at least one of the following conditions 5-1) to 5-4) is satisfied.

[0308] 5-1) If the selected or reselected cell is not the cell set in the RRC connection release message.

[0309] 5-2) When the RRC state changes or transitions to the RRC connected state

[0310] 5-3) When Inter-RAT cell selection or reselection occurs

[0311] 5-4) If a Public Land Mobile Network (PLMN) or Standalone Non-Public Network (SNPN) is selected due to a Non-Access Stratum (NAS) request.

[0312] Of course, the terminal (801) may also maintain the WUS configuration information received via the RRC connection release message even if at least one of the conditions 5-1) to 5-4) above is satisfied. This is because the terminal (801) may later select or reselect a cell that can use the WUS configuration information received via the RRC connection release message.

[0313] FIG. 9 is a diagram illustrating a procedure for a terminal in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE) to reselect a cell for transmitting System Information Block 1 (SIB1) on-demand in a wireless communication system according to an embodiment of the present disclosure.

[0314] A given cell according to the present disclosure may periodically transmit essential system information, which means at least one of a Master Information Block (MIB) and a System Information Block 1 (SIB1). The essential system information includes configuration information required for a terminal to select or camp on a cell. Additionally, a given cell according to the present disclosure may transmit the MIB periodically, but may transmit the SIB1 on-demand, unlike the above-described embodiment (Fig. 5). This is because network energy can be saved by transmitting the SIB1 when a terminal requests it.

[0315] Referring to FIG. 9, the terminal (901) may be in an RRC connected state (RRC_CONNECTED) by establishing an RRC connection with an NR cell (905) (910).

[0316] At step 915, the terminal (901) may transmit terminal capability information (UECapabilityInformation) to the NR cell (905). The terminal capability information may include at least one of the following capability information.

[0317] - Capability information to transmit a wake-up signal (WUS), which is a signal to request a cell transmitting SIB1 on-demand to transmit SIB1.

[0318] - Ability to receive SIB1 per cell or per cell list via RRC disconnection message

[0319] - Ability to receive some SIB1 information per cell or per cell list via RRC disconnection message.

[0320] - Capability information that can be used by applying configuration information for a wake-up signal (hereinafter referred to as WUS), which is a signal to request a cell that transmits SIB1 on-demand via an RRC disconnection message (and / or system information) to transmit SIB1.

[0321] In step 920, the NR cell (905) may transmit an RRC connection release message (RRCRelease) to release the RRC connection with the terminal (901) in the RRC connection state. The RRC connection release message may include at least one of the information of 1-1) to 1-4) described in the embodiment of FIG. 6, the new timer value (hereinafter, the first timer value) in the embodiment of FIG. 7, the information of 4-1) and 4-2) in the embodiment of FIG. 8, and the new timer value (hereinafter, the second timer value) below.

[0322] - New timer value: The new timer value may refer to a timer value that controls how long the terminal (901) applies the configuration information required when transmitting the WUS received in the RRC connection release message. The terminal (901) that has received the new timer value may run the timer with the corresponding value after receiving the RRC connection release message. While the timer is running, the configuration information required when transmitting the WUS received through the RRC connection release message may be used. When the timer is stopped or expires, the configuration information required when transmitting the WUS received through the RRC connection release message may be released.

[0323] The terminal (901) in the RRC connection state may, after applying / confirming the information included in the RRC connection release message, transition (925) from the RRC connection state to the RRC idle state (RRC_IDLE) or the RRC inactive state (RRC_INACTIVE) at step 925, as in the embodiment described above.

[0324] At step 930, a terminal (901) in an RRC idle state or an RRC inactive state can obtain essential system information, MIB and SIB1, from an NR cell (905).

[0325] In step 935, the terminal (901) may perform a cell selection procedure based on step 930. The basic operation of the cell selection procedure may follow the embodiment of FIG. 5 described above.

[0326] At step 940, the terminal (901) may obtain system information (e.g., SIB2, SIB3, SIB4, SIB5, new SIB) containing cell reselection information from the serving cell (905) to perform a cell reselection evaluation procedure. This may follow at least one of the embodiments of FIGS. 5 to 8 described above.

[0327] At step 945, the terminal (901) may determine a reselection priority for cell reselection. This may follow the embodiment described above (Fig. 5).

[0328] At step 947, a cell (907) transmitting SIB1 in an on-demand manner can transmit a synchronization signal, SSB (Synchronization Signal / PBCH block, hereinafter referred to as SSB).

[0329] At step 950, the terminal (901) may perform frequency measurement for cell reselection. This may follow the embodiment described above (Fig. 5).

[0330] In step 955, the terminal (901) may determine a candidate target cell that satisfies the cell reselection criteria based on the measurement values ​​performed in step 950. This may follow the aforementioned embodiment (Fig. 5). Accordingly, the terminal according to the present disclosure may determine the final candidate target cell as the NR cell (907). That is, the NR cell (907) may be the best cell or the highest-ranked cell for the terminal (901).

[0331] At step 960, the terminal (901) can confirm that the NR cell (907) transmits SIB1 on-demand. For example, the terminal (901) can confirm whether the NR cell will transmit SIB1 on-demand through an RRC connection release message (step 920) or through system information (step 940). In the following embodiment, it is assumed that the candidate target NR cell (907) can transmit SIB1 on-demand.

[0332] At step 965, the terminal (901) can transmit a WUS to the candidate target NR cell (807) to receive SIB1 from the candidate target NR cell (907). For example, if the new timer driven at step 920 is driven and the WUS configuration information for the candidate target NR cell (907) can be applied through the RRC connection release message (step 920), the terminal (901) can transmit a WUS to the candidate target NR cell (807) to receive SIB1 from the candidate target NR cell (907) based on the WUS configuration information. In an optional embodiment, if the terminal (901) cannot apply the WUS configuration information for the candidate target NR cell (907) through the RRC connection release message and can apply the WUS configuration information for the candidate target NR cell (907) through the system information (step 940), the terminal (901) may transmit a WUS to the candidate target NR cell (907) to receive SIB1 from the candidate target NR cell (907) based on the WUS configuration information received through the system information (step 940). That is, the terminal (901) may give priority to the WUS configuration information set in the RRC connection release message over the WUS configuration broadcasted in the system information.

[0333] At step 970, the NR cell (907) can transmit SIB1 and the terminal (901) can receive it. For reference, the terminal (901) can receive the MIB transmitted by the NR cell (907) at step 970 or at a previous step (e.g., step 947, step 955, or step 960).

[0334] At step 975, the terminal (901) determines whether the reception level (Srxlev) and reception quality (Squal) of the candidate target NR cell (907) satisfy a cell selection criterion (Srxlev > 0 AND Squal > 0) called S-criterion (see the embodiment of FIG. 5 described above, mathematical expression 1) based on the essential system information (MIB and / or SIB1) received from the candidate target NR cell. If the S-criterion is satisfied and the candidate target NR cell (907) is suitable, the terminal (901) can reselect the candidate target NR cell (907).

[0335] The terminal (901) according to the present disclosure can transmit a WUS to a candidate target NR cell (907) to receive SIB1 from the candidate target NR cell (907) transmitting SIB1 on-demand. The terminal (901) can obtain the configuration information for transmitting the WUS through an RRC connection release message or through system information. As an optional embodiment, the terminal (901) can stop a running new timer if at least one of the following conditions 6-1) to 6-5) is satisfied.

[0336] 6-1) If the selected or reselected cell is not the cell set in the RRC connection release message.

[0337] 6-2) When the RRC state changes or transitions to the RRC connected state

[0338] 6-3) When Inter-RAT cell selection or reselection occurs

[0339] 6-4) If a Public Land Mobile Network (PLMN) or Standalone Non-Public Network (SNPN) is selected due to a Non-Access Stratum (NAS) request.

[0340] 6-5) When the required configuration information is not set when transmitting WUS in the received RRC connection release message or a new timer value is not set

[0341] Of course, the terminal (901) may continue to run the running new timer even if at least one of the conditions 6-1) to 6-5) is satisfied. This is because the terminal (901) may later select or reselect a cell that can use the WUS configuration information received via the RRC connection release message. As an optional embodiment, the terminal (901) may stop the running new timer or, when the running new timer expires, delete the WUS configuration information received via the RRC connection release message.

[0342] FIG. 10 is a diagram illustrating a procedure in which a terminal performs a random access procedure with a base station to request System Information Block 1 (SIB1) in a wireless communication system according to an embodiment of the present disclosure, and the terminal reports information related thereto to the base station.

[0343] In the present disclosure, a terminal can acquire SIB1 from a cell that transmits SIB1 in an on-demand manner by triggering a random access procedure. Specifically, the terminal can transmit a wake-up signal (hereinafter referred to as WUS) through a PRACH preamble(s) in RACH resource(s), thereby acquiring SIB1 from a base station of the corresponding cell.

[0344] Referring to FIG. 10, at step 1010, the terminal (1001) can transmit a WUS to a cell (1005) that transmits SIB1 in an on-demand manner by triggering a random access procedure according to a predetermined event (e.g., cell selection or cell reselection). The terminal (1001) can obtain WUS configuration information and a method thereof based on at least one of the above-described embodiments. The terminal (1001) can transmit a wake-up signal (hereinafter, WUS) to the cell (1005) through PRACH preamble(s) in RACH resource(s).

[0345] At step 1020, the terminal (1001) can obtain SIB1 transmitted by the cell (1005) based on the WUS. If the terminal (1001) receives an acknowledgment for the SIB 1 request from lower layers, the terminal (1001) can obtain the requested SIB1 from the cell (1005).

[0346] At step 1030, the terminal (1001) that has acquired the SIB1 can enter an RRC connected state (RRC_CONNECTED) by establishing an RRC connection with the cell (1005). The terminal (1001) can enter an RRC connected state through an RRC connection establishment procedure or an RRC connection resume procedure with the cell in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE).

[0347] At step 1040, the cell (1005) can transmit a terminal information request message (UEInformationRequest) containing an ra-ReportReq requesting the terminal (1001) to perform the following RA-Report to the terminal (1001).

[0348] In step 1050, the terminal (1001) that received the ra-ReportReq can transmit a terminal information response message (UEInformationResponse) including an ra-ReportList to the cell (1005). The RA-ReportList includes one or more RA-Reports, and in the present embodiment, the RA-Report can include at least one of the following information 7-1) to 7-3).

[0349] 7-1) If the purpose of the random access procedure (raPurpose) is to request on-demand SIB1, a directive to indicate this may be included. For example, a new directive, requestForSIB1, may be set in raPurpose, or at least one of the previously defined directives may indicate that the purpose of the random access procedure (raPurpose) is to request on-demand SIB1. For reference, a description of the previously defined directives may be as shown in [Table 9] below.

[0350] [Table 9]

[0351]

[0352] 7-2) Information for indicating the SSB(s) used when the terminal receives SIB1 from the base station (i.e., SSB index(s)) may be included.

[0353] 7-3) If the terminal successfully acquires On-demand SIB1, an indicator may be included to indicate this. Of course, a separate indicator may also be included to indicate whether On-demand SIB1 acquisition was successful or failed.

[0354] As an optional embodiment, at least one of the information of 7-1) to 7-3) in the present embodiment may be applied to at least one of the RLF (Radio Link Failure) Report, CEF (Connection Establishment Failure) Report, SuccessHO (handover)-Report, and SuccessPSCell Report defined in the 3GPP standard.

[0355] FIG. 11 is a diagram illustrating a procedure in which a terminal performs a random access procedure with a base station to request System Information Block 1 (SIB1) in a wireless communication system according to an embodiment of the present disclosure, and the terminal reports information related thereto to the base station.

[0356] A cell according to the present disclosure can transmit SIB1 periodically. Additionally, a cell according to the present disclosure can transmit SIB1 on-demand upon a terminal request. A terminal according to the present disclosure has the characteristic of being able to quickly acquire SIB1 on-demand by triggering a random access procedure when it determines that the SIB1 transmission cycle is long.

[0357] Referring to FIG. 11, at step 1110, the terminal (1101) can camp on an NR cell (1105).

[0358] In steps 1115 and 1120, the NR cell (1107) may periodically broadcast SIB1. Specifically, the NR cell (1107) may broadcast SIB1 in steps 1115 and 1120 according to the SIB1 transmission cycle (1117). In the present embodiment, when the terminal (1101) is camping on the NR cell (1105), it may not receive system information (1115, 1120) broadcast by the neighboring cell (1107).

[0359] At step 1125, the terminal (1101) may determine that it is necessary to acquire SIB1 from the NR cell (1107) due to a predetermined event (e.g., cell selection or cell reselection).

[0360] At step 1130, if the terminal (1101) determines that the SIB1 transmission cycle (1117) of the NR cell (1107) is long or if it wants to quickly acquire SIB1 (by triggering a random access procedure), it can transmit WUS to the NR cell (1107).

[0361] At step 1135, the terminal (1101) can obtain SIB1 transmitted by the cell (1107) based on the WUS. For example, if the terminal (1101) receives an acknowledgment for the SIB 1 request from lower layers, the terminal (1101) can obtain the requested SIB1 from the cell (1107).

[0362] At step 1140, the terminal (1101) can enter an RRC connected state (RRC_CONNECTED) by establishing an RRC connection with the cell (1107). The terminal (1101) can enter an RRC connected state through an RRC connection establishment procedure or an RRC connection resume procedure with the cell (1107) in an RRC idle state (RRC_IDLE) or an RRC inactive state (RRC_INACTIVE).

[0363] At step 1145, the cell (1107) can transmit a terminal information request message (UEInformationRequest) including ra-ReportReq to the terminal (1101) as in the embodiment of FIG. 10.

[0364] At step 1150, the terminal (1101) may transmit a terminal information response message (UEInformationResponse) including an ra-ReportList to the cell (1107) as in the embodiment of FIG. 10. The RA-ReportList includes one or more RA-Reports, and in the present embodiment, the RA-Report may include at least one of the following information 8-1) to 8-5).

[0365] 8-1) If the purpose (raPurpose) of the random access procedure, such as the example in [Table 9] above, was to request on-demand SIB1, an indicator to indicate this may be included. This may follow the embodiment described above (Fig. 10). Information indicating the SSB(s) used when receiving SIB1 (i.e., SSB index(s)) may be included.

[0366] 8-2) If On-demand SIB1 acquisition was successful, an indicator may be included to indicate this. Of course, a separate indicator may also be included to indicate whether On-demand SIB1 acquisition was successful or not.

[0367] 8-3) The SIB1 transmission cycle may be long, so an indicator may be included indicating that on-demand SIB1 has been requested.

[0368] 8-4) The actual SIB1 transmission cycle may be included.

[0369] 8-5) The actual desired SIB1 transmission cycle may be included.

[0370] As an optional embodiment, at least one of the information of 8-1) to 8-5) in the present embodiment may be applied to at least one of RLF Report, CEF Report, SuccessHO-Report, and SuccessPSCell Report defined in the 3GPP standard.

[0371] FIG. 12 is a diagram illustrating a terminal operation in a wireless communication system according to an embodiment of the present disclosure in which the terminal stores mobility history information and reports it to a base station.

[0372] A terminal that supports storing mobility history information can store its mobility history information in a terminal variable, VarMobilityHistoryReport, if certain conditions are met. Specifically, a terminal according to the present disclosure can store mobility history information in VarMobilityHistoryReport if at least one of the following conditions 1 to 3 is met.

[0373] - Condition 1: Upon change of suitable cell:

[0374] 1) When the current PCell (NR or E-UTRA cell) is changed to another NR or E-UTRA cell in RRC_CONNECTED (for NR or E-UTRA) state.

[0375] 2) When the NR serving cell in RRC_INACTIVE state is changed to another NR serving cell or E-UTRA cell (for NR cell) or

[0376] 3) When the serving cell in RRC_IDLE (for NR or E-UTRA cell) changes to another NR or E-UTRA cell

[0377] - Condition 2: When the terminal enters any cell selection state from the camped normally state in NR or LTE system.

[0378] - Condition 3: When a terminal in an RRC connected state in an NR or LTE system enters any cell selection state from a suitable cell (entering any cell selection state from a suitable cell in RRC_CONNECTED in NR or LTE)

[0379] Referring to FIG. 12, at step 1210, the terminal (1201) may transmit a wake-up signal (WUS) to the NR cell (1205) based on at least one of the embodiments described above.

[0380] In step 1220, the terminal (1201) can obtain SIB1 transmitted on-demand by the NR cell (1205). As an optional embodiment, the terminal (1201) can also obtain SIB1 periodically broadcast by the NR cell (1205) without performing step 1210.

[0381] At step 1230, the terminal (1201) can select or reselect an NR cell (1205) based on the acquired SIB1.

[0382] At step 1240, the terminal (1201) can select or reselect another NR cell (1207). For example, although not shown, the terminal (1201) can obtain SIB1 for the other NR cell (1207) in advance using at least one of the embodiments of FIGS. 6 to 9 described above, and select or reselect the other NR cell (1207) based on the obtained SIB1 for the other NR cell (1207).

[0383] At step 1245, the terminal (1201) can store mobility history information in VarMobilityHistoryReport according to the following operation 1 proposed in the present embodiment if at least one of the above-described conditions 1 to 3 is satisfied.

[0384] - Action 1: If necessary, include an entry in variable VarMobilityHistoryReport possibly after removing the oldest entry, if necessary, according to the following. Action 1 may include at least one of the following sub-actions 1) to 3).

[0385] 1) If the global cell identifier of the previous PCell or serving cell is available, the global cell identifier of the previous PCell or serving cell can be stored in the visitedCellId field (if the global cell identity of the previous PCell / serving cell is available, include the global cell identity of that cell in the fieldvisitedCellIdof the entry). Otherwise, the carrier frequency and physical cell identifier of the previous PCell or serving cell can be stored in the visitedCellId field (else, include the physical cell identity and carrier frequency of that cell in the fieldvisitedCellIdof the entry). That is, for the NR cell (1205), the global cell identifier or the carrier frequency and physical cell identifier can be stored in the visitedCellId field. And the time spent in the previous PCell or serving cell can be stored in the timeSpent field (set the fieldtimeSpentof the entry as the time spent in the previous PCell / serving cell).

[0386] 2) Information indicating whether a request for broadcasting SIB1 from an NR cell (1205) was received or whether SIB1 broadcast periodically was received can be stored.

[0387] 3) When SIB1 periodically broadcast from NR cell (1205) is received, the SIB1 transmission cycle or the SIB1 transmission cycle desired by the terminal (1201) can be stored.

[0388] At step 1250, the terminal (1201) can enter the RRC connected state (RRC_CONNECTED) by establishing an RRC connection with the NR cell (1207) according to cell selection or cell reselection.

[0389] At step 1255, the NR cell (1207) can transmit a terminal information request message (UEInformationRequest) containing mobilityHistoryReportReq to the terminal (1201).

[0390] At step 1260, the terminal (1201) can transmit a terminal information response message (UEInformationResponse) containing mobilityHistoryReport to the NR cell (1207). Specifically, the terminal can perform the above-described operation 1 for the current cell (1207) and transmit a terminal information response message including the entry value in the VarMobilityHistoryReport in mobilityHistoryReport to the NR cell (1207).

[0391] FIG. 13 is a block diagram illustrating the internal structure of a terminal according to an embodiment of the present disclosure.

[0392] Referring to the above drawing, the terminal may include an RF (Radio Frequency) processing unit (1310), a baseband processing unit (1320), a storage unit (1330), and a control unit (1340).

[0393] The RF processing unit (1310) performs functions for transmitting and receiving signals through a wireless channel, such as signal band conversion and amplification. That is, the RF processing unit (1310) up-converts the baseband signal provided from the baseband processing unit (1320) into an RF band signal and transmits it through an antenna, and down-converts the RF band signal received through the antenna into a baseband signal. For example, the RF processing unit (1310) may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital to analog convertor (DAC), an analog to digital convertor (ADC), etc. In the drawing, only one antenna is illustrated, but the terminal may be equipped with multiple antennas. In addition, the RF processing unit (1310) may include multiple RF chains. Furthermore, the RF processing unit (1310) may perform beamforming. For the above beamforming, the RF processing unit (1310) can adjust the phase and size of each signal transmitted and received through multiple antennas or antenna elements. In addition, the RF processing unit can perform MIMO and receive multiple layers when performing the MIMO operation.

[0394] The baseband processing unit (1320) performs a conversion function between a baseband signal and a bit stream according to the physical layer specifications of the system. For example, when transmitting data, the baseband processing unit (1320) generates complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the baseband processing unit (1320) restores the reception bit stream by demodulating and decoding the baseband signal provided from the RF processing unit (1310). For example, in the case of an orthogonal frequency division multiplexing (OFDM) method, when transmitting data, the baseband processing unit (1320) generates complex symbols by encoding and modulating a transmission bit stream, maps the complex symbols to subcarriers, and then configures OFDM symbols by performing an inverse fast Fourier transform (IFFT) operation and inserting a cyclic prefix (CP). In addition, when receiving data, the baseband processing unit (1320) divides the baseband signal provided from the RF processing unit (1310) into OFDM symbol units, restores signals mapped to subcarriers through FFT (fast Fourier transform), and then restores the received bit string through demodulation and decoding.

[0395] The baseband processing unit (1320) and the RF processing unit (1310) transmit and receive signals as described above. Accordingly, the baseband processing unit (1320) and the RF processing unit (1310) may be referred to as a transmitter, a receiver, a transceiver, or a communication unit. Furthermore, at least one of the baseband processing unit (1320) and the RF processing unit (1310) may include a plurality of communication modules to support a plurality of different wireless access technologies. In addition, at least one of the baseband processing unit (1320) and the RF processing unit (1310) may include different communication modules to process signals of different frequency bands. For example, the different wireless access technologies may include a wireless LAN (e.g., IEEE 802.11), a cellular network (e.g., LTE), etc. Additionally, the different frequency bands may include a super high frequency (SHF) (e.g., 2.NRHz, NRhz) band and a millimeter wave (mm wave) (e.g., 60GHz) band.

[0396] The storage unit (1330) stores data such as basic programs, application programs, and setting information for the operation of the terminal according to at least one of the embodiments of FIGS. 1 to 12. Furthermore, the storage unit (1330) may store information related to a second access node that performs wireless communication using a second wireless access technology. Furthermore, the storage unit (1330) provides the stored data upon request from the control unit (1340).

[0397] The control unit (1340) controls the overall operations of the terminal according to at least one of the embodiments of FIGS. 1 to 12. For example, the control unit (1340) transmits and receives signals through the baseband processing unit (1320) and the RF processing unit (1310). In addition, the control unit (1340) records and reads data in the storage unit (1340). For this purpose, the control unit (1340) may include at least one processor. For example, the control unit (1340) may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls upper layers such as application programs.

[0398] Additionally, the terminal of FIG. 13 may be implemented by including a transceiver capable of transmitting and receiving a wireless signal with a base station and a processor that controls the operation of the terminal according to at least one of the embodiments of FIGS. 1 to 12 described above.

[0399] FIG. 14 is a block diagram showing the configuration of an NR base station according to an embodiment of the present disclosure.

[0400] As shown in the above drawing, the base station may include an RF processing unit (1410), a baseband processing unit (1420), a backhaul communication unit (1430), a storage unit (1440), and a control unit (1450).

[0401] The RF processing unit (1410) performs functions for transmitting and receiving signals through a wireless channel, such as signal band conversion and amplification. That is, the RF processing unit (1410) up-converts the baseband signal provided from the baseband processing unit (1420) into an RF band signal and transmits it through an antenna, and down-converts the RF band signal received through the antenna into a baseband signal. For example, the RF processing unit (1410) may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc. In the drawing, only one antenna is illustrated, but the first access node may have multiple antennas. In addition, the RF processing unit (1410) may include multiple RF chains. Furthermore, the RF processing unit (1410) may perform beamforming. For the above beamforming, the RF processing unit (1410) can adjust the phase and size of each signal transmitted and received through multiple antennas or antenna elements. The RF processing unit can perform a downlink MIMO operation by transmitting one or more layers.

[0402] The baseband processing unit (1420) performs a conversion function between a baseband signal and a bit stream according to the physical layer specifications of the first wireless access technology. For example, when transmitting data, the baseband processing unit (1420) generates complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the baseband processing unit (1420) restores the reception bit stream by demodulating and decoding the baseband signal provided from the RF processing unit (1410). For example, in the case of OFDM, when transmitting data, the baseband processing unit (1420) generates complex symbols by encoding and modulating a transmission bit stream, maps the complex symbols to subcarriers, and then configures OFDM symbols through IFFT operation and CP insertion. In addition, when receiving data, the baseband processing unit (1420) divides the baseband signal provided from the RF processing unit (1410) into OFDM symbol units, restores the signals mapped to subcarriers through FFT operation, and then restores the received bit string through demodulation and decoding. The baseband processing unit (1420) and the RF processing unit (1410) transmit and receive signals as described above. Accordingly, the baseband processing unit (1420) and the RF processing unit (1410) may be referred to as a transmitter, a receiver, a transceiver, a communication unit, or a wireless communication unit.

[0403] The backhaul communication unit (1430) provides an interface for communicating with other nodes within the network. That is, the backhaul communication unit (1430) converts a bit string transmitted from the main base station to another node, such as an auxiliary base station or core network, into a physical signal, and converts a physical signal received from the other node into a bit string.

[0404] The storage unit (1440) stores data such as basic programs, application programs, and setting information for the operation of the base station according to at least one of the embodiments of FIGS. 1 to 12. Furthermore, the storage unit (1440) may store information on bearers assigned to connected terminals, measurement results reported from connected terminals, and the like. Furthermore, the storage unit (1440) may store information that serves as a basis for determining whether to provide or terminate multiple connections to a terminal. Furthermore, the storage unit (1440) provides the stored data upon request from the control unit (1450).

[0405] The control unit (1450) controls the overall operations of the base station according to at least one of the embodiments of FIGS. 1 to 12. For example, the control unit (1450) transmits and receives signals through the baseband processing unit (1420) and the RF processing unit (1410) or through the backhaul communication unit (1430). In addition, the control unit (1450) records and reads data in the storage unit (1440). For this purpose, the control unit (1450) may include at least one processor.

[0406] Additionally, the base station of FIG. 14 may be implemented by including a transceiver capable of transmitting and receiving a wireless signal with a terminal and a processor that controls the operation of the base station according to at least one of the embodiments of FIGS. 1 to 12 described above.

Claims

1. In a method for a terminal to receive system information in a wireless communication system, A process in which the terminal, which is in an RRC (radio resource control) connection state with the first base station of the first cell, transmits terminal capability information for receiving the system information to the first base station; and A process in which the terminal receives an RRC connection release message including configuration information for cell selection or cell reselection of the terminal from the first base station based on the terminal capability information, A method wherein the above setting information includes at least a portion of the system information for a second cell that is a candidate target cell for the cell selection or the cell reselection and at least one of information for receiving the system information.

2. In paragraph 1, The above system information includes SIB1 (system information block1) of the second cell, The above terminal capability information is: Capability information capable of transmitting a wake-up signal (WUS) to request provision of the SIB1 on-demand to the second base station of the second cell transmitting the SIB1; Capability information to receive SIB1 per cell or per cell list via the RRC disconnection message, and A method comprising at least one of the capability information for receiving some SIB1 per cell or per cell list via the RRC connection release message.

3. In paragraph 1, The above system information includes SIB1 of the second cell, A method wherein the above configuration information includes at least one of SIB1 per cell for the candidate target cell, SIB1 per cell list, SIB1 per frequency, and measurement-related parameters for the candidate target cell.

4. In paragraph 1, A process in which the terminal, having received the RRC connection release message, transitions from the RRC connection state to the RRC idle state or RRC inactive state; and A method further comprising a process of performing a cell selection or cell reselection procedure for the second cell based on the configuration information included in the RRC connection release message.

5. In paragraph 1, A method wherein the RRC connection release message further includes timer information indicating an applicable period of the configuration information.

6. In a wireless communication system, at the terminal, Transmitter and receiver; and In a state of RRC (radio resource control) connection with the first base station of the first cell, terminal capability information for receiving system information is transmitted to the first base station through the transceiver, and A processor configured to receive, through the transceiver, an RRC connection release message including configuration information for cell selection or cell reselection of the terminal from the first base station based on the terminal capability information, A terminal including at least a portion of the system information for a second cell, which is a candidate target cell for the cell selection or the cell reselection, and at least one of information for receiving the system information.

7. In paragraph 6, The above system information includes SIB1 (system information block1) of the second cell, The above terminal capability information is: Capability information capable of transmitting a wake-up signal (WUS) to request provision of the SIB1 on-demand to the second base station of the second cell transmitting the SIB1; Capability information to receive SIB1 per cell or per cell list via the RRC disconnection message, and A terminal including at least one capability information capable of receiving some SIB1 per cell or per cell list via the RRC connection release message.

8. In paragraph 6, The above system information includes SIB1 of the second cell, The above configuration information is a terminal including at least one of SIB1 per cell for the candidate target cell, SIB1 per cell list, SIB1 per frequency, and measurement-related parameters for the candidate target cell.

9. In paragraph 6, The above processor, The terminal that received the RRC connection release message transitions from the RRC connection state to the RRC idle state or RRC inactive state, A terminal further configured to control performing a cell selection or cell reselection procedure for the second cell based on the configuration information included in the RRC connection release message.

10. In paragraph 6, A terminal in which the RRC connection release message further includes timer information indicating the applicable period of the setting information.

11. In a base station in a wireless communication system, Transmitter and receiver; and Through the above transceiver, terminal capability information related to transmission of system information is received from a terminal in an RRC (radio resource control) connection state with the base station of the first cell, and A processor configured to transmit, to the terminal, an RRC connection release message including configuration information for cell selection or cell reselection of the terminal through the transceiver based on the terminal capability information, A base station, wherein the above-mentioned setting information includes at least a portion of the system information for a second cell, which is a candidate target cell for the cell selection or the cell reselection, and at least one of information for transmitting the system information.

12. In paragraph 11, The above system information includes SIB1 (system information block1) of the second cell, The above terminal capability information is: Capability information capable of transmitting a wake-up signal (WUS) to request provision of the SIB1 on-demand to another base station of the second cell transmitting the SIB1; Capability information to receive SIB1 per cell or per cell list via the RRC disconnection message, and A base station including at least one capability information capable of receiving some SIB1 per cell or per cell list via the RRC connection release message.

13. In paragraph 11, The above system information includes SIB1 of the second cell, A base station including at least one of the above-mentioned configuration information, SIB1 per cell for the candidate target cell, SIB1 per cell list, SIB1 per frequency, and measurement-related parameters for the candidate target cell.

14. In paragraph 11, A base station wherein the RRC connection release message further includes timer information indicating the applicable period of the configuration information.

15. In paragraph 11, The above processor, A base station further configured to transmit system information including cell reselection information used in the evaluation procedure of the cell reselection at the terminal through the transceiver.

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