Method and apparatus for performing communication in a mobile communication system

Abstract

A user equipment (UE) for performing communication, the UE comprising: a transceiver; and a processor, coupled to the transceiver and configured to: control the transceiver to receive a UE capability query, determine UE capability fields other than a frequency division duplex (FDD) additional UE capability field, a time division duplex (TDD) additional UE capability field, a frequency range 1 (FR 1) additional UE capability field, and a frequency range 2 (FR 2) additional UE capability field to include values ​​applicable to all duplex modes and frequency ranges, and control the transceiver to send UE capability information based on a result of the determination.

Description

Technical Field

[0001] The present disclosure relates to a mobile communication system, and more particularly, to a method and apparatus for performing communication between a Base Station (BS) and a User Equipment (UE) in the mobile communication system. Background Art

[0002] In order to meet the growing demand for wireless data services after the commercialization of the fourth generation (4G) communication system, efforts have been made to develop an enhanced fifth generation (5G) new radio (NR) communication system. In order to achieve high data transmission rates, the 5G communication system is designed to support ultra-high frequency bands (millimeter wave (mmWave)), for example, a frequency band of 28 GHz. In order to reduce the occurrence of stray radio waves and increase the transmission distance of radio waves in the ultra-high frequency band, various technologies for 5G communication systems are being studied, such as: beamforming, massive multiple input multiple output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antennas. In addition, unlike the long-term evolution (LTE) system, the 5G communication system supports various subcarrier spacings, such as 15 kHz, 30 kHz, 60 kHz, and 120 kHz. The physical control channel uses polarization coding, and the physical data channel uses low-density parity check (LDPC). In addition, as a waveform for uplink transmission, not only cyclic prefix-orthogonal frequency division multiplexing (CP-OFDM) but also discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-S-OFDM) is used. LTE can support hybrid automatic repeat request (HARQ) retransmission in a transport block (TB) unit, but 5G can additionally support HARQ retransmission in a code block group (CBG) unit in which a plurality of code blocks (CBs) are grouped.

[0003] To improve the system network of 5G communication systems, various technologies have been developed, including evolved small cells, advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device-to-device communication (D2D), wireless backhaul, vehicle-to-everything (V2X) networks, cooperative communications, coordinated multi-point (CoMP), and interference cancellation.

[0004] The Internet has evolved from a human-based connection network in which humans create and consume information to the Internet of Things (IoT) in which distributed configurations (such as objects) exchange information with each other to process information. Internet of Everything (IoE) technology has emerged, in which IoT technology is combined with technology for processing big data, such as by connecting to a cloud server. In order to implement IoT, various technical elements are required, such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology, so that in recent years, technologies related to sensor networks, machine-to-machine (M2M) communication and machine type communication (MTC) for connecting objects have been studied. In the IoT environment, intelligent Internet technology (IT) services can be provided to collect and analyze data obtained from connected objects to create new value in human life. As existing information technology (IT) and various industries merge and combine with each other, IoT can be applied to various fields, such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, health care, smart appliances and advanced medical services.

[0005] For this reason, attempts are being made to apply 5G communication systems to IoT networks. For example, technologies related to sensor networks, M2M communications, and MTC are being implemented by using 5G communication technologies including beamforming, MIMO, and array antennas. Cloud Radio Access Network (Cloud RAN) as an application of the above-mentioned big data processing technology may be an example of the fusion of 5G communication technology and IoT technology. In this way, a variety of services can be provided to users in a communication system, and in order to provide a variety of services to users, a method for providing each service in the same time period according to the characteristics of each service, and a device using the method are required. Various services provided by 5G communication systems are being studied, and one of the various services is a service that meets the requirements of low latency and high reliability. The service is called ultra-reliable and low-latency communication (URLLC).

[0006] Since various services can be provided due to the aforementioned technical features and the development of wireless communication systems, a method for efficiently providing these services is required. Summary of the invention

[0007] Technical issues

[0008] As the aforementioned technical features and the development of wireless communication systems can provide various services, a method for efficiently providing these services is required.

[0009] Technical Solutions

[0010] A user equipment (UE) for performing communication, the UE comprising: a transceiver; and a processor, coupled to the transceiver and configured to: control the transceiver to receive a UE capability query, determine UE capability fields other than a frequency division duplex (FDD) additional UE capability field, a time division duplex (TDD) additional UE capability field, a frequency range 1 (FR 1) additional UE capability field, and a frequency range 2 (FR 2) additional UE capability field to include values ​​applicable to all duplex modes and frequency ranges, and control the transceiver to send UE capability information based on a result of the determination. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals represent like parts:

[0012] Figure 1A A diagram showing the architecture of a Long Term Evolution (LTE) system according to an embodiment of the present disclosure;

[0013] Figure 1B A diagram showing a radio protocol architecture of an LTE system according to an embodiment of the present disclosure;

[0014] Figure 1C A diagram showing the architecture of a next generation mobile communication system according to an embodiment of the present disclosure;

[0015] Figure 1D A diagram showing a radio protocol architecture of a next generation mobile communication system according to an embodiment of the present disclosure;

[0016] Figure 1E A diagram for describing a process performed by a user equipment (UE) to transition from a radio resource control (RRC) connected mode to an RRC idle mode and from an RRC connected mode to an RRC idle mode according to a connection state between the UE and a base station (BS) according to an embodiment of the present disclosure is shown;

[0017] Figure 1Fa , 1Fb 1Fc is a diagram for describing a process of transmitting and receiving UE radio access capability information between a BS and a UE in an RRC connected mode according to an embodiment of the present disclosure;

[0018] Figure 2A A diagram showing an example of a message flow between a UE and a BS when a method of sending a scheduling request is used according to an embodiment of the present disclosure;

[0019] Figure 2B A flowchart showing an example of an operation sequence of a UE when a method of sending a scheduling request is used according to an embodiment of the present disclosure;

[0020] Figure 3A A diagram showing a downlink (DL) and uplink (UL) channel frame structure for describing beam-based communication performed in a new radio (NR) system according to an embodiment of the present disclosure;

[0021] Figure 3B A diagram for describing a cell reselection process in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to an embodiment of the present disclosure is shown;

[0022] Figure 3C A diagram for describing a cell reselection process in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown;

[0023] Figure 3D A diagram for describing a cell reselection process in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown;

[0024] Figure 3E A diagram for describing a cell reselection process in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown;

[0025] Figure 3F A diagram for describing a cell reselection process in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown;

[0026] Figure 3G A diagram for describing a cell reselection procedure in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown.

[0027] Figure 3H A block diagram of a UE according to an embodiment of the present disclosure is shown; and

[0028] Fig. 3I A block diagram of a BS according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0029] According to an embodiment of the present disclosure, a method for providing information about capabilities of a user equipment (UE) in a mobile communication system is provided. According to an embodiment of the present disclosure, a method for using a plurality of scheduling request resources configured in a base station (BS) in a mobile communication system so as to request resources for data transmission by a UE is provided. According to an embodiment of the present disclosure, a method for performing cell reselection by a UE in response to channel bandwidth signaling in a mobile communication system is provided.

[0030] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments of the disclosure.

[0031] According to an embodiment of the present disclosure, a user equipment (UE) for performing communication includes: a transceiver; and a processor, coupled to the transceiver and configured to: control the transceiver to receive a UE capability query, determine UE capability fields other than a frequency division duplex (FDD) additional UE capability field, a time division duplex (TDD) additional UE capability field, a frequency range 1 (FR 1) additional UE capability field, and a frequency range 2 (FR 2) additional UE capability field to include values ​​applicable to all duplex modes and frequency ranges, and control the transceiver to send UE capability information based on the result of the determination.

[0032] The processor may also be configured to, when the UE supports FDD and TDD functionality and at least one of the UE capability fields has different values ​​for FDD and TDD, determine whether the UE supports additional functionality for FDD compared to functionality indicated by a previous UE capability field, and in response to the UE supporting the additional functionality for FDD, determine the FDD additional UE capability field to reflect the additional functionality for FDD.

[0033] The processor may also be configured to, when the UE supports FDD and TDD functionality and at least one of the UE capability fields has different values ​​for FDD and TDD, determine, for TDD, whether the UE supports additional functionality compared to functionality indicated by a previous UE capability field, and, in response to the UE supporting the additional functionality of TDD, determine the TDD additional UE capability field to reflect the additional functionality of TDD.

[0034] The processor may also be configured to, when the UE supports functionality of FR1 and FR2 and at least one of the UE capability fields has different values ​​for FR1 and FR2, determine, for FR1, whether the UE supports additional functionality compared to functionality indicated by a previous UE capability field, and, in response to the UE supporting the additional functionality of FR1, determine an additional UE capability field for FR1 to reflect the additional functionality of FR1.

[0035] The processor may also be configured to, when the UE supports functionality of FR1 and FR2 and at least one of the UE capability fields has different values ​​for FR1 and FR2, determine, for FR2, whether the UE supports additional functionality compared to functionality indicated by a previous UE capability field, and, in response to the UE supporting the additional functionality of FR2, determine the FR2 additional UE capability field to reflect the additional functionality of FR2.

[0036] In case the RAT type of the UE capability query is set to NR, the UE capability field includes the UE-NR-capability field.

[0037] According to another embodiment of the present disclosure, a base station for performing communication includes: a transceiver; and a processor, coupled to the transceiver and configured to: control the transceiver to send a user equipment (UE) capability query, and receive UE capability information in response to the UE capability query, wherein UE capability fields of the UE capability information other than an FDD (frequency division duplex) additional UE capability field, a time division duplex (TDD) additional UE capability field, a frequency range 1 (FR 1) additional UE capability field, and a frequency range 2 (FR 2) additional UE capability field are determined to include values ​​applicable to all duplex modes and frequency ranges.

[0038] According to another embodiment of the present disclosure, a method for performing communication performed by a user equipment (UE) includes: receiving a UE capability query; determining UE capability fields other than a frequency division duplex (FDD) additional UE capability field, a time division duplex (TDD) additional UE capability field, a FR 1 (frequency range 1) additional UE capability field, and a frequency range 2 (FR 2) additional UE capability field to include values ​​applicable to all duplex modes and frequency ranges; and sending UE capability information based on a result of the determination.

[0039] According to an embodiment of the present disclosure, a method for performing communication performed by a base station includes: sending a UE capability query; and receiving UE capability information in response to the UE capability query, wherein UE capability fields of the UE capability information other than an FDD (frequency division duplex) additional UE capability field, a TDD (time division duplex) additional UE capability field, a frequency range 1 (FR 1) additional UE capability field, and a frequency range 2 (FR 2) additional UE capability field are determined to include values ​​applicable to all duplex modes and frequency ranges.

[0040] Before proceeding to the following detailed description, it may be helpful to set forth definitions of certain words and phrases used throughout this patent document: the terms "include" and "comprising" and their derivatives mean inclusion rather than limitation; the term "or" is inclusive, meaning and / or; the phrases "associated with" and "associated with" and their derivatives may mean including, included, interconnected with, containing, contained within, connected to or connected with, coupled to or coupled with, communicable with, cooperating with, intertwined, juxtaposed, proximate, bound to or bound with, having, having the property of, etc.; and the term "controller" means any device, system, or part thereof that controls at least one operation, such device may be implemented in hardware, firmware, or software, or some combination of at least two thereof. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely.

[0041] In addition, the various functions described below can be implemented or supported by one or more computer programs, each of which is formed by a computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, processes, functions, objects, classes, instances, related data, or parts thereof suitable for implementation in a suitable computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as a read-only memory (ROM), a random access memory (RAM), a hard drive, a compact disk (CD), a digital video disc (DVD), or any other type of memory. "Non-transitory" computer-readable media does not include wired, wireless, optical, or other communication links that transmit temporary electrical or other signals. Non-transitory computer-readable media include media in which data can be permanently stored and media in which data can be stored and then rewritten, such as rewritable optical disks or erasable storage devices.

[0042] Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.

[0043] Invention Mode

[0044] Discussed below FIG. 1A to FIG. 3IThe various embodiments used to describe the principles of the present disclosure in this patent document are merely exemplary and should not be interpreted in any way as limiting the scope of the present disclosure. Those skilled in the art will appreciate that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0045] Hereinafter, the operating principle of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or configurations are not described in detail because they would obscure the present disclosure with unnecessary details. The terms used in the specification are defined in consideration of the functions used in the present disclosure and may be changed according to the intention or common methods of the user or operator. Therefore, the definition of the terms is understood based on the entire description of this specification.

[0046] Throughout the present disclosure, the expression “at least one of a, b, or c” means only a, only b, only c, a and b, a and c, b and c, all of a, b, and c, or variations thereof.

[0047] Examples of the terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, a multimedia system capable of performing a communication function, and the like.

[0048] In this disclosure, a controller may also be referred to as a processor.

[0049] Throughout this specification, a layer (or layer arrangement) may also be referred to as an entity.

[0050] It should be understood that the blocks in the flowchart or the combination of flowcharts can be executed by computer program instructions. Because these computer program instructions can be loaded into a processor of a general-purpose computer, a special-purpose computer, or another programmable data processing device, the instructions executed by the processor of the computer or another programmable data processing device create a unit for performing the functions described in the (multiple) flowchart blocks. The computer program instructions can be stored in a computer-usable or computer-readable memory that can instruct a computer or another programmable data processing device to implement the functions in a specific manner, so the instructions stored in the computer-usable or computer-readable memory can also produce a manufactured product containing instruction units for performing the functions described in the (multiple) flowchart blocks. The computer program instructions can also be loaded into a computer or another programmable data processing device, so when a series of operations are performed in the computer or another programmable data processing device, the instructions for operating the computer or another programmable data processing device by generating a computer-executed process can provide operations for performing the functions described in the (multiple) flowchart blocks.

[0051] In addition, each box can represent a part of a module, segment or code, which includes one or more executable instructions for performing (multiple) specified logical functions. It should also be noted that in some alternative embodiments, the functions mentioned in the box can appear out of order. For example, two consecutive boxes can be executed simultaneously or in reverse order according to the corresponding functions.

[0052] As used herein, the term "unit" represents a software element or a hardware element, such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), and performs a certain function. However, the term "unit" is not limited to software or hardware. A "unit" may be formed in an addressable storage medium, or may be formed to operate one or more processors. Therefore, for example, the term "unit" may include an element (e.g., a software element, an object-oriented software element, a class element, and a task element), a process, a function, a property, a procedure, a subroutine, a program code segment, a driver, a firmware, a microcode, a circuit, data, a database, a data structure, a table, an array, or a variable. The function provided by the element and the "unit" may be combined into a smaller number of elements and "units", or may be divided into additional elements and "units". In addition, the element and the "unit" may be embodied as reproducing one or more central processing units (CPUs) in a device or a secure multimedia card. In addition, in an embodiment of the present disclosure, a "unit" may include at least one processor.

[0053] In the present disclosure, downlink (DL) refers to a wireless transmission path for a signal to be sent from a base station (BS) to a UE, and uplink (UL) refers to a wireless transmission path for a signal to be sent from a UE to a BS. Although the following description of a long term evolution (LTE) or advanced LTE (LTE-A) system may be provided as an example, embodiments of the present disclosure are also applicable to other communication systems having similar technical backgrounds or channel structures. For example, embodiments of the present disclosure may be applicable to systems including fifth generation (5G) new radio (NR) communication technologies developed after LTE-A systems, and hereinafter, 5G may indicate concepts including LTE, LTE-A and other similar services according to related technologies. The present disclosure is applicable to other communication systems through any modification by a person of ordinary skill in the art without greatly departing from the scope of the present disclosure.

[0054] Hereinafter, for the convenience of explanation, the terms identifying access nodes, the terms indicating network entities, the terms indicating messages, the terms indicating interfaces between network entities, and the terms indicating various identification information used in the following description are exemplified. Therefore, the present disclosure is not limited to the terms to be described below, and other terms indicating objects having the same technical meaning may be used.

[0055] For ease of description, the present disclosure uses terms and names defined in the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) standard. However, the present disclosure is not limited to these terms and names and can be equally applied to communication systems that comply with other standards. In the present disclosure, for ease of explanation, evolved Node B (eNB) can be used interchangeably with next generation Node B (gNB). That is, a BS described by eNB can represent a gNB.

[0056] In the following description of the present disclosure, well-known functions or configurations are not described in detail because they would obscure the present disclosure with unnecessary detail. Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0057] Figure 1A A diagram showing the architecture of an LTE system according to an embodiment of the present disclosure.

[0058] refer to Figure 1A , the radio access network of the LTE system may include multiple next-generation base stations (e.g., evolved Node Bs (eNBs), Node Bs, or BSs) 1a-05, 1a-10, 1a-15, and 1a-20, a mobility management entity (MME) 1a-25, and a serving gateway (S-GW) 1a-30. A UE (or terminal) 1a-35 may access an external network via the eNBs 1a-05, 1a-10, 1a-15, or 1a-20 and the S-GW 1a-30.

[0059] exist Figure 1A In the present invention, eNB1a-05, 1a-10, 1a-15 or 1a-20 may correspond to an existing Node B of a Universal Mobile Telecommunications System (UMTS). eNB 1a-05, 1a-10, 1a-15 or 1a-20 may be connected to UE 1a-35 through a wireless channel and perform complex functions compared to the existing Node B. In an LTE system, all user traffic data including real-time services such as Voice over Internet Protocol (VoIP) may be served through a shared channel. Therefore, an entity for performing scheduling by checking status information of the UE, including buffer status information, available transmission power status information and channel status information, may be required, and eNB 1a-05, 1a-10, 1a-15 or 1a-20 may operate as such an entity.

[0060] One eNB can usually control multiple cells. For example, the LTE system can use radio access technologies such as orthogonal frequency division multiplexing (OFDM) at a bandwidth of 20MHz to achieve a data rate of 100Mbps. The LTE system can also use adaptive modulation & coding (AMC) to determine the modulation scheme and channel coding rate according to the channel state of UE 1a-35. eNB1a-05, 1a-10, 1a-15 and 1a-20, which are access nodes of the cellular network, can provide wireless access to UEs accessing the network. That is, in order to serve the user's business, eNB1a-05, 1a-10, 1a-15 and 1a-20 can perform scheduling by checking the status information of the UE, which includes buffer status information, available transmit power status information and channel status information, and can support the connection between the UE and the core network (CN).

[0061] S-GW 1a-30 is an entity for providing data bearers, and can generate or remove data bearers by the control of MME 1a-25. MME 1a-25 is an entity for performing mobility management functions and various control functions on UE 1a-35, and can be connected to multiple eNBs 1a-05, 1a-10, 1a-15, and 1a-20.

[0062] MME 1a-25 and S-GW 1a-30 may also perform authentication, bearer management, etc. regarding UE attempting to access the network, and may process packets received from eNB 1a-05, 1a-10, 1a-15, or 1a-20 or packets to be sent to eNB 1a-05, 1a-10, 1a-15, or 1a-20.

[0063] Figure 1B A diagram showing a radio protocol architecture of an LTE system according to an embodiment of the present disclosure.

[0064] refer to Figure 1B The radio protocol architecture of the LTE system may include packet data convergence protocol (PDCP) layers 1b-05 and 1b-40, radio link control (RLC) layers 1b-10 and 1b-35, medium access control (MAC) layers 1b-15 and 1b-30, and physical (PHY) layers 1b-20 and 1b-25 for UE and LTE eNB, respectively. The PDCP layer 1b-05 or 1b-40 is responsible for, for example, Internet Protocol (IP) header compression / decompression. The main functions of the PDCP layer 1b-05 or 1b-40 are summarized as follows.

[0065] -Header compression and decompression: Robust Header Compression only (ROHC)

[0066] - Passing user data

[0067] - In-sequence delivery of upper layer packet data units (PDUs) during PDCP re-establishment in RLC Acknowledged Mode (AM)

[0068] - For split bearer for DC (supported only for RLC AM): PDCP PDU routing for transmission and PDCP PDU reordering for reception

[0069] - Repeated detection of lower layer service data units (SDUs) during PDCP re-establishment of RLC AM

[0070] - For RLC AM, PDCP PDUs are retransmitted during handover and for split bearers of DC, PDCP PDUs are retransmitted during PDCP data recovery

[0071] -Encryption and decryption

[0072] - Timer-based SDU discard in uplink

[0073] For example, the RLC layer 1b-10 or 1b-35 may perform an automatic repeat request (ARQ) operation by reconfiguring the PDCP PDU to an appropriate size. The main functions of the RLC layer 1b-10 or 1b-35 are summarized as follows.

[0074] -Transfer upper layer PDU

[0075] - Error correction via ARQ (for AM data transfer only)

[0076] - RLC SDU concatenation, segmentation and reassembly (only for Unacknowledged Mode (UM) and AM data delivery)

[0077] - Re-segmentation of RLC data PDU (only for AM data delivery)

[0078] - Reordering of RLC data PDUs (only for UM and AM data delivery)

[0079] - Duplicate detection (for UM and AM data delivery only)

[0080] -Protocol error detection (for AM data transfer only)

[0081] -RLC·SDU discard (only for UM and AM data transfer)

[0082] -RLC re-establishment

[0083] The MAC layer 1b-15 or 1b-30 may be connected to a plurality of RLC layers configured for one UE, and may multiplex RLC PDUs into MAC PDUs and demultiplex RLC PDUs from MAC PDUs. The main functions of the MAC layer 1b-15 or 1b-30 are summarized as follows.

[0084] - Mapping between logical channels and transport channels

[0085] - Multiplexing / demultiplexing MAC SDUs belonging to one or different logical channels to / from a transport block (TB) delivered to / from the physical layer on a transport channel

[0086] -Dispatch information report

[0087] - Error correction through Hybrid ARQ (HARQ)

[0088] - Priority handling between logical channels of a UE

[0089] - Priority handling between UEs through dynamic scheduling

[0090] -Multimedia Broadcast / Multicast Service (MBMS) service identifier

[0091] -Transmission format selection

[0092] -filling

[0093] The PHY layer 1b-20 or 1b-25 may channel-code and modulate upper layer data into OFDM symbols and transmit the OFDM symbols through a wireless channel, or may demodulate OFDM symbols received through a wireless channel, channel-decode the OFDM symbols and deliver them to an upper layer.

[0094] The PHY layer 1b-20 or 1b-25 also uses HARQ for additional error correction, and the receiver sends 1-bit information indicating whether a packet sent from the transmitter is received. Such information is called HARQ acknowledgement (ACK) / negative acknowledgement (NACK) information. DL HARQ ACK / NACK information for UL transmission can be sent through the physical HARQ indication channel (PHICH), and UL HARQ ACK / NACK information for DL ​​transmission can be sent through the physical uplink control channel (PUCCH) or the physical uplink shared channel (PUSCH). PUSCH can be used for the UE to send not only HARQ ACK / NACK information to the eNB, but also channel state information (CSI), scheduling request (SR), etc. SR is 1-bit information, and when the UE sends SR in the resources in the PUCCH configured by the eNB, the eNB recognizes that the UE has data to be sent through UL and allocates UL resources accordingly. The UE can send a detailed buffer status report (BSR) through UL resources. The eNB can allocate multiple SR resources to a single UE.

[0095] The PHY layer 1b-20 or 1b-25 may include one or more frequencies / carriers, and the technology of configuring and using multiple frequencies simultaneously by one eNB is called carrier aggregation (CA). CA technology can increase one carrier used for communication between UE and E-UTRAN Node B (eNB) to a main carrier and one or more subcarriers, thereby greatly increasing the data rate through multiple subcarriers. In LTE, the cell using the main carrier in the eNB is called the primary cell (PCell), and the cell using the subcarrier is called the secondary cell (SCell). The technology that extends CA capabilities to two eNBs is called dual connection (DC) technology. In DC technology, the UE can be connected to the main eNB (MeNB) and the secondary eNB (SeNB) at the same time, and can use both of them, and the cell belonging to the MeNB can be called the main cell group (MCG), and the cell belonging to the SeNB can be called the secondary cell group (SCG). Each cell group can have a representative cell. The representative cell of the MCG can be called the PCell, and the representative cell of the SCG can be called the primary secondary cell (PSCell). When using NR, MCG is used for LTE and SCG is used for NR, allowing the UE to use LTE and NR at the same time.

[0096] Although not shown, there is an RRC layer above the PDCP layer of the UE and the base station, and the RRC layer can exchange control messages related to access and measurement of radio resource control. For example, the eNB can instruct the UE to perform measurement by using a message of the RRC layer, and the UE can report the measurement result to the eNB by using a message of the RRC layer.

[0097] Figure 1C A diagram showing the architecture of a next generation mobile communication system according to an embodiment of the present disclosure.

[0098] refer to Figure 1C , the radio access network of the next generation mobile communication system (e.g., NR or 5G system) includes a next generation BS (e.g., new radio node B (NR gNB or NR BS) 1c-10 and a new radio core network (NR CN) 1c-05. NR UE (or NR terminal) 1c-15 can access an external network via NR gNB 1c-10 and NR CN1c-05.

[0099] exist Figure 1C In the NR or 5G system, the NR gNB 1c-10 may correspond to an existing evolved Node B (eNB) of an existing LTE system. The NR gNB1c-10 may be connected to the NR UE 1c-15 through a wireless channel and may provide better services than the existing Node B. In the NR or 5G system, all user service data may be served through a shared channel. Therefore, an entity for performing scheduling by checking, for example, the buffer status information, available transmit power status information, and channel status information of the UE may be required, and the NR gNB 1c-10 may operate as such an entity. One NR gNB 1c-10 may control multiple cells. In the NR or 5G system, a bandwidth larger than the maximum bandwidth of the existing LTE system may be applied to achieve an ultra-high data rate. In the NR or 5G system, beamforming technology may be additionally associated with OFDM as a radio access technology. In addition, AMC may also be used to determine the modulation scheme and channel coding rate according to the channel status of the NR UE 1c-15.

[0100] NR CN 1c-05 can perform functions such as mobility support, bearer establishment, and quality of service (QoS) configuration. NR CN 1c-05 is an entity for performing mobility management functions and various control functions on NR UE 1c-15, and can be connected to multiple base stations. NR or 5G system can cooperate with the existing LTE system, and NR CN 1c-05 can be connected to MME 1c-25 through a network interface. MME1c-25 can be connected to the existing eNB1c-30.

[0101] Figure 1D A diagram showing a radio protocol architecture of a next generation mobile communication system according to an embodiment of the present disclosure.

[0102] refer to Figure 1DThe radio protocol architecture of the next generation mobile communication system may include NR service data adaptation protocol (SDAP) layers 1d-01 and 1d-45, NR PDCP layers 1d-05 and 1d-40, NR RLC layers 1d-10 and 1d-35, NR MAC layers 1d-15 and 1d-30, and NR PHY layers 1d-20 and 1d-25 for UE and NR gNB, respectively.

[0103] The main functions of NRSDAP layer 1d-01 or 1d-45 may include some of the following.

[0104] -Transfer user plane data

[0105] - Mapping between QoS flows and Data Radio Bearers (DRBs) for DL ​​and UL

[0106] - Marking QoS flow identification (ID) in DL and UL packets

[0107] -Reflective QoS flow for UL SDAP PDU to DRB mapping

[0108] Regarding NR SDAP layer 1d-01 or 1d-45, information about whether to use the header of NR SDAP layer 1d-01 or to use the function of NR SDAP layer 1d-01 can be configured for the UE by using a radio resource control (RRC) message for each PDCP layer, each bearer, or each logical channel. When the SDAP header is configured, a 1-bit non-access stratum (NAS) reflected QoS indicator and a 1-bit access stratum (AS) reflected QoS indicator of the SDAP header can be used to guide the UE to update or reconfigure UL and DL QoS flows and data bearer mapping information. The SDAP header may include QoS flow ID information indicating QoS. QoS information can be used as data processing priority information or scheduling information for appropriately supporting services.

[0109] The main functions of NRPDCP layer 1d-05 or 1d-40 may include some of the following.

[0110] -Header compression and decompression: ROHC only

[0111] - Passing user data

[0112] - Sequential delivery of upper layer PDUs

[0113] - Out-of-order delivery of upper layer PDUs

[0114] - Reordering of received PDCP PDUs

[0115] - Duplicate detection of lower layer SDU

[0116] -Retransmitted PDCP SDU

[0117] *115-Encryption and decryption

[0118] - Timer-based SDU discard in uplink

[0119] In the foregoing description, the reordering function of the NR PDCP layer 1d-05 or 1d-40 may indicate a function of reordering PDCP PDUs received from a lower layer based on a PDCP sequence number (SN). The reordering function of the NR PDCP layer 1d-05 or 1d-40 may include a function of delivering reordered data to an upper layer in sequence or out of sequence, a function of recording lost PDCP PDUs by reordering received PDCP PDUs, a function of reporting status information of lost PDCP PDUs to a transmitter, or a function of requesting retransmission of lost PDCP PDUs.

[0120] The main functions of the NRRLC layer 1d-10 or 1d-35 may include at least some of the following.

[0121] -Transfer upper layer PDU

[0122] - Sequential delivery of upper layer PDUs

[0123] - Out-of-order delivery of upper layer PDUs

[0124] - Error correction via ARQ

[0125] - RLC SDU splicing, segmentation and reassembly

[0126] - Re-segmentation of RLC data PDUs

[0127] - Reordering of RLC data PDUs

[0128] - Duplicate detection

[0129] -Protocol error detection

[0130] -RLC·SDU discard

[0131] -RLC re-establishment

[0132] In the above description, the sequential delivery function of the NR RLC layer 1d-10 or 1d-35 may indicate a function of delivering the RLC SDU received from the lower layer to the higher layer in sequence. When a plurality of RLC SDUs segmented from one RLC SDU are received, the sequential delivery function of the NR RLC layer 1d-10 or 1d-35 may include a function of reassembling the RLC SDU and delivering the reassembled RLC SDU.

[0133] The sequential delivery function of the NR RLC layer 1d-10 or 1d-35 may include at least one of a function of reordering the received RLC PDU based on the RLC SN or PDCP SN, a function of recording lost RLC PDUs by reordering the received RLC PDUs, a function of reporting status information of lost RLC PDUs to a transmitter, or a function of requesting retransmission of lost RLC PDUs.

[0134] When a lost RLC SDU exists, the sequential delivery function of the NR RLC layer 1d-10 or 1d-35 may include a function of delivering only the RLC SDU before the lost RLC SDU to the upper layer.

[0135] The sequential delivery function of the NR RLC layer 1d-10 or 1d-35 may include a function of delivering all RLC SDUs received before the timer is started to the upper layer in sequence when a certain timer expires, even when lost RLC SDUs exist.

[0136] The sequential delivery function of the NR RLC layer 1d-10 or 1d-35 may include a function of delivering all RLC SDUs received until the current time to the upper layer in sequence when a certain timer expires, even when a lost RLC SDU exists.

[0137] The NR RLC layer 1d-10 or 1d-35 can process the RLC PDU in the order of receipt and can deliver the RLC PDU to the NR PDCP layer 1d-05 or 1d-40 regardless of the SN (out-of-order delivery).

[0138] When a segment is received, the NRRLC layer 1d-10 or 1d-35 can reassemble the segment with other segments stored in the buffer or received subsequently into a complete RLC PDU, and can deliver the RLC PDU to the NRPDCP layer 1d-05 or 1d-40.

[0139] The NR RLC layer 1d-10 or 1d-35 may not have a splicing function, and the splicing function may be performed by the NR MAC layers 1d-15 and 1d-30, or replaced by the multiplexing function of the NR MAC layers 1d-15 and 1d-30.

[0140] In the above description, the out-of-order delivery function of the NR RLC layer 1d-10 or 1d-35 may refer to a function of directly delivering the RLC SDU received from the lower layer to the higher layer out of order. The out-of-order delivery function of the NR RLC layer 1d-10 or 1d-35 may include a function of reassembling multiple RLC SDUs segmented from one RLC SDU, and delivering the reassembled RLC SDU when the segmented RLC SDU is received. The out-of-order delivery function of the NR RLC layer 1d-10 or 1d-35 may include a function of recording lost RLC PDUs by storing the RLC PDUs or PDCP PDUs of the received RLC PDUs and reordering the received RLC PDUs.

[0141] NR MAC layers 1d-15 and 1d-30 can be connected to multiple NR RLC layers configured for one UE, and the main functions of NR MAC layers 1d-15 and 1d-30 may include some of the following functions.

[0142] - Mapping between logical channels and transport channels

[0143] -Multiplex / demultiplex MAC SDU

[0144] -Dispatch information report

[0145] - Error correction through HARQ

[0146] - Priority handling between logical channels of a UE

[0147] - Priority handling between UEs through dynamic scheduling

[0148] -MBMS service logo

[0149] -Transmission format selection

[0150] -filling

[0151] The NRPHY layers 1d-20 and 1d-25 may encode and modulate an upper layer data channel into an OFDM symbol and transmit the OFDM symbol through a wireless channel, or may demodulate an OFDM symbol received through a wireless channel, channel-decode the OFDM symbol and deliver it to an upper layer.

[0152] Figure 1E A diagram is shown for describing a process performed by a UE according to an embodiment of the present disclosure of transitioning from an RRC connected mode to an RRC idle mode and from an RRC idle mode to an RRC connected mode according to a connection state between the UE and a BS including an eNB, a gNB, etc.

[0153] According to an embodiment of the present disclosure, when a UE configured to send and receive data in RRC connection mode does not send or receive data due to a predetermined reason or within a predetermined time, the BS may send an RRCConnectionRelease message to the UE to allow the UE to transition to RRC idle mode (1e-01). Thereafter, when a UE that is not currently configured for connection (hereinafter also referred to as an idle mode UE) has data to send or receive, the UE may perform an RRC connection establishment procedure on the BS.

[0154] The UE may establish reverse transmission synchronization with the BS through a random access procedure, and may send an RRCConnectionRequest message to the BS (1e-05). The RRCConnectionRequest message may include an identifier of the UE, an establishment cause, and the like.

[0155] The BS may send an RRCConnectionSetup message to allow the UE to establish an RRC connection (1e-10). The RRCConnectionSetup message may include RRC connection configuration information, etc. The RRC connection may also be described as a signaling radio bearer (SRB) and may be used to send and receive RRC messages that are control messages between the UE and the BS.

[0156] The UE establishing the RRC connection may send an RRCConnectionSetupComplete message (1e-15) to the BS. The RRCConnectionSetupComplete message may include a control message of a service request (SERVICE REQUEST) by which the UE requests the MME or the Access Mobility Management Function (AMF) to establish a bearer for a certain service.

[0157] The BS may send a control message of the service request included in the RRCConnectionSetupCompletem message to the MME or AMF (1e-20), and the MME or AMF may determine whether to provide the service requested by the UE.

[0158] As a result of the determination, when the MME or AMF determines to provide the service requested by the UE, the MME or AMF may send an INITIAL CONTEXT SETUP REQUEST message (1e-25) to the BS. The INITIAL CONTEXT SETUP REQUEST message may include QoS information to be applied to the DRB configuration, security information to be applied to the DRB (e.g., security key, security algorithm, etc.), etc.

[0159] The BS may exchange SecurityModeCommand messages (1e-30) and SecurityModeComplete messages (1e-35) with the UE in order to configure security.

[0160] When the security configuration is completed, the BS may send an RRCConnectionReconfiguration message to the UE (1e-40). The RRCConnectionReconfiguration message may include configuration information about DRBs to process user data, and the UE may configure the DRBs by using the configuration information about the DRBs, and may send an RRCConnectionReconfigurationComplete message to the BS (1e-45).

[0161] After the BS completes the DRB configuration with the UE, the BS may send an INITIAL CONTEXT SETUP COMPLETE message to the MME or AMF (1e-50), and upon receiving the message, the MME or AMF exchanges an S1 bearer setup (BEARER SETUP) message and an S1 bearer setup response (BEARER SETUPRESPONSE) message (1e-55 and 1e-60) with the S-GW or the user plane function (UPF) to configure the S1 bearer. The S1 bearer indicates a connection established between the S-GW or UPF and the BS for data transmission, and may correspond one-to-one to the DRB.

[0162] When the aforementioned process is completed, the UE can transmit and receive data to / from the BS via the S-GW or UPF (1e-65 and 1e-70). As described above, the general data transmission process can be composed of roughly 3 steps, namely, RRC connection configuration, security configuration, and DRB configuration.

[0163] Due to predefined reasons, the BS may send the RRCConnectionReconfiguration message to newly allocate, add, or change configuration for the UE (1e-75).

[0164] Figure 1Fa A diagram is shown for describing a process of sending and receiving UE radio access capability information between a BS 1f-02 including an eNB, a gNB, etc. and a UE 1f-01 in an RRC connected mode according to an embodiment of the present disclosure.

[0165] According to an embodiment of the present disclosure, when requesting UE radio access capability information and / or additionally requesting UE radio access capability information, BS1f-02 may send a UECapabilityEnquiry message (1f-05) to UE 1f-01 in RRC connected mode. The UECapabilityEnquiry message may be sent when BS1f-02 requests not only UE radio access capability (also called UE capability) relative to NR but also UE radio access capability relative to radio access technology (RAT) to UE 1f-01 in RRC connected mode. Therefore, the UECapabilityEnquiry message may include a UE-CapabilityRAT-RequestList information element (IE), which is a user capability request list regarding one or more RATs, and the UE-CapabilityRAT-Request requesting user capability regarding each RAT may include the following information.

[0166] -rat-Type: The RAT type for which the network requests UE capabilities (the RAT type for which the network requests UE capabilities). For example, one of the RAT types including nr, eutra-nr, eutra, and multi-radio dual connectivity (MR-DC) excluding eutra-nr can be set as rat-Type.

[0167] -capabilityRequestFilter: Information that the network requests the UE to filter UE capabilities (information that the network requests the UE to filter UE capabilities). For example, when rat-Type is set to nr, capabilityRequestFilter may include information defined in UE-CapabilityRequestFilterNR (e.g., the value of frequencyBandlist or FreqBandList relative to NR).

[0168] When UE 1f-01 in RRC connected mode receives a UECapabilityEnquiry message from BS1f-02, UE 1f-01 can deliver UE radio access capability (1f-10) by sending a UECapabilityInformation message to BS1f-02. The UECapabilityInformation message may include a UE-CapabilityRAT-ContainerList IE as a UE capability container list for one or more RATs, and a UE-CapabilityRAT-Container as a UE capability container for each RAT may include the following information.

[0169] -rat-Type: RAT type supported by UE 1f-01 in RRC connected mode. For example, one of the RAT types may be set to rat-Type, and the RAT types include nr, eutra-nr, eutra, and MR-DC does not include eutra-nr. For example, according to the method of setting the RAT type, when UE 1f-01 supports NR among the RATs requested by BS1f-02 in 1f-05, the RAT type may be set to nr.

[0170] -ue-CapabilityRAT-Container: A container including UE capability information indicated by rat-Type. For example, when rat-Type is set to nr, ue-CapabilityRAT-Container may include information defined in UE-NR-Capability (NR UE radio access capability parameter).

[0171] In 1f-10, when UE 1f-01 in RRC connected mode sends a UECapabilityInformation message to BS 1f-02, UE 1f-01 performs the following operations.

[0172] 1> When the UECapabilityEnquiry message received in 1f-05 includes nr and UE 1f-01 supports NR:

[0173] 2>UE 1f-01 may set rat-Type to nr, and may include UE-NR-Capability in ue-CapabilityRAT-Container. In this regard, according to an embodiment of the present disclosure, the method of including UE-NR-Capability performed by UE 1f-01 may be one of the following methods.

[0174] *When UE 1f-01 supports all of Frequency Division Duplex (FDD), Time Division Duplex (TDD), Frequency Range 1 (FR1), and Frequency Range 2 (FR2),

[0175] -UE 1f-01 may set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE-NR-Capabilities, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to FDD, TDD, FR1, and FR2 (set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE-NR-Capabilities, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to FDD, TDD, FR1, and FR2).

[0176] - when some fields of UE-NR-Capability have different values ​​for FDD and TDD (if (some) UE capability fields have different values ​​for FDD and TDD),

[0177] ◇ In case of FDD, when UE 1f-01 must support additional functionality, compared with the setting of the previous field of UE-NR-Capability (if for FDD, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-NR-Capability),

[0178] UE 1f-01 may include the fdd-Add-UE-NR-Capabilities field in UE-NR-Capability, and may set the fdd-Add-UE-NR-Capabilities field to include a field value reflecting other additional functions applicable to FDD (including the field fdd-Add-UE-NR-Capabilities, and setting it to include a field reflecting additional functions applicable to FDD).

[0179] ◇ In case of TDD, when UE 1f-01 must support additional functions, compared with the setting of the previous field of UE-NR-Capability,

[0180] UE 1f-01 may include a tdd-Add-UE-NR-Capabilities field in UE-NR-Capability, and may set the tdd-Add-UE-NR-Capabilities field to include a field value reflecting other additional functions applicable to TDD.

[0181] - When some fields of UE-NR-Capability have different values ​​for FR1 and FR2,

[0182] ◇ In case of FR1, when UE 1f-01 must support additional functions, compared with the setting of the previous field of UE-NR-Capability,

[0183] UE 1f-01 may include the fr1-Add-UE-NR-Capabilities field in UE-NR-Capability, and may set the fr1-Add-UE-NR-Capabilities field to include a field value reflecting other additional functions applicable to FR1. (Include the field fr1-Add-UE-NR-Capabilities, and set it to include a field reflecting additional functions applicable to FR1).

[0184] ◇ In case of FR2, when the UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-NR-Capability (if for FR2, the UE supports additional functionality compared to that indicated by the previous field of UE-NR-Capability),

[0185] UE 1f-01 may include the fr2-Add-UE-NR-Capabilities field in UE-NR-Capability, and may set the fr2-Add-UE-NR-Capabilities field to include a field value reflecting other additional functions applicable to FR2. (Include the fr2-Add-UE-NR-Capabilities field and set it to include a field reflecting additional functions applicable to FR2).

[0186] *When UE 1f-01 supports both FDD and TDD, and supports one of FR1 and FR2 (in the present disclosure, FRx is used to indicate one of FR1 and FR2) (otherwise, if UE supports both FDD and TDD and a single FRx),

[0187] -UE 1f-01 may set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE--NR-Capabilies, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to FDD, TDD, and FRx (set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE--NR-Capabilies, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to FDD, TDD, and FRx).

[0188] - when some fields of UE-NR-Capability have different values ​​for FDD and TDD (if (some) UE capability fields have different values ​​for FDD and TDD),

[0189] ◇ In case of FDD, when the UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-NR-Capability (if for FDD, the UE supports additional functionality compared to the functionality indicated by the previous field of UE-NR-Capability),

[0190] ·UE 1f-01 may include the fdd-Add-UE-NR-Capabilities field in UE-NR-Capability, and may set the fdd-Add-UE-NR-Capabilities field to include a field value reflecting other additional functions applicable to FDD (include the field fdd-Add-UE-NR-Capabilities and set it to include a field reflecting additional functions applicable to FDD).

[0191] ◇ In case of TDD, when UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-NR-Capability (if for TDD, the UE supports additional functionality compared to the functionality indicated by the previous field of UE-NR-Capability),

[0192] UE 1f-01 may include the tdd-Add-UE-NR-Capabilities field in UE-NR-Capability, and may set the tdd-Add-UE-NR-Capabilities field to include a field value reflecting other additional functions applicable to TDD (including the field tdd-Add-UE-NR-Capabilities, and setting it to include a field reflecting additional functions applicable to TDD).

[0193] *When UE 1f-01 supports one of FDD and TDD (in the present disclosure, xDD is used to indicate one of FDD and TDD), and supports both FR1 and FR2 (otherwise if the UE supports a single xDD mode and both FR1 and FR2),

[0194] -UE 1f-01 may set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE-NR-Capabilities, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to xDD, FR1, and FR2 (set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE-NR-Capabilities, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to xDD, FR1, and FR2).

[0195] -UE 1f-01 may set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE-NR-Capabilities, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to xDD, FR1, and FR2 (set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE-NR-Capabilities, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to xDD, FR1, and FR2).

[0196] - when some fields of UE-NR-Capability have different values ​​for FR1 and FR2 (if (some) UE capability fields have different values ​​for FR1 and FR2),

[0197] ◇ In case of FR1, when UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-NR-Capability (if for FR1, the UE supports additional functionality compared to the functionality indicated by the previous field of UE-NR-Capability),

[0198] UE 1f-01 may include the fr1-Add-UE-NR-Capabilities field in UE-NR-Capability, and may set the fr1-Add-UE-NR-Capabilities field to include a field value reflecting other additional functions applicable to FR1. (Include the field fr1-Add-UE-NR-Capabilities and set it to include a field reflecting additional functions applicable to FR1).

[0199] ◇ In case of FR2, when the UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-NR-Capability (if for FR2, the UE supports additional functionality compared to that indicated by the previous field of UE-NR-Capability),

[0200] UE 1f-01 may include the fr2-Add-UE-NR-Capabilities field in UE-NR-Capability, and may set the fr2-Add-UE-NR-Capabilities field to include a field value reflecting other additional functions applicable to FR2. (Include the fr2-Add-UE-NR-Capabilities field and set it to include a field reflecting additional functions applicable to FR2).

[0201] *When UE 1f-01 supports one of FDD and TDD, and supports one of FR1 and FR2 (otherwise if UE supports single xDD mode and single FRx),

[0202] -UE 1f-01 may set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE-NR-Capabilities, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to xDD and FRx (set all fields of UE-NR-Capability except fdd-Add-UE-NR-Capabilities, tdd-Add-UE-NR-Capabilities, fr1-Add-UE-NR-Capabilities, and fr2-Add-UE-NR-Capabilities to include values ​​applicable to xDD and FRx).

[0203] 2>UE 1f-01 can include the supported NR band combinations in supportedBandCombination.

[0204] 1> When the UECapabilityEnquiry message received in 1f-05 includes eutra and UE1f-01 supports E-UTRA:

[0205] 2>UE 1f-01 may set rat-Type to eutra and may include UE-EUTRA-Capability in ue-CapabilityRAT-Container. In this regard, the method of including UE-EUTRA-Capability performed by UE 1f-01 may be determined according to "36.306: Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) Radio Access Capabilities".

[0206] 1> When the UECapabilityEnquiry message received in 1f-05 includes one of the MR-DCs other than eutra-nr or eutra-nr, and UE 1f-01 supports the indicated MR-DC:

[0207] 2>UE 1f-01 can set rat-Type to one of MR-DC other than eutra-nr or eutra-nr, and can include UE-MRDC-Capability in ue-CapabilityRAT-Container. In this regard, according to an embodiment of the present disclosure, the method of including UE-MRDC-Capability performed by UE 1f-01 can be one of the following methods.

[0208] *When UE 1f-01 supports all of FDD, TDD, FR1, and FR2,

[0209] -UE 1f-01 may set all fields of UE-MRDC-Capability except fdd-Add-UE-MRDC-Capabilities, tdd-Add-UE-MRDC-Capabilities, fr1-Add-UE-MRDC-Capabilities, and fr2-Add-UE-MRDC-Capabilities to include values ​​applicable to FDD, TDD, FR1, and FR2 (set all fields of UE-MRDC-Capability except fdd-Add-UE-MRDC-Capabilities, tdd-Add-UE-MRDC-Capabilities, fr1-Add-UE-MRDC-Capabilities, and fr2-Add-UE-MRDC-Capabilities to include values ​​applicable to FDD, TDD, FR1, and FR2).

[0210] - when some fields of UE-MRDC-Capability have different values ​​for FDD and TDD (if (some) UE capability fields have different values ​​for FDD and TDD),

[0211] ◇ In case of FDD, when UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-MDRC-Capability (if for FDD, the UE supports additional functionality compared to the functionality indicated by the previous field of UE-MRDC-Capability),

[0212] ·UE 1f-01 may include the fdd-Add-UE-MRDC-Capabilities field in UE-MRDC-Capability, and may set the fdd-Add-UE-MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FDD (including the field fdd-Add-UE-MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to FDD).

[0213] ◇ In case of TDD, when UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-MRDC-Capability (if for TDD, the UE supports additional functionality compared to the functionality indicated by the previous field of UE-MRDC-Capability),

[0214] ·UE 1f-01 may include the tdd-Add-UE-MRDC-Capabilities field in UE-MRDC-Capability, and may set the tdd-Add-UE-MRDC-Capabilities field to include a field value reflecting other additional functions applicable to TDD (including the field tdd-Add-UE-MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to TDD).

[0215] - when some fields of UE-MRDC-Capability have different values ​​for FR1 and FR2 (if (some) UE capability fields have different values ​​for FR1 and FR2),

[0216] ◇ In case of FR1, when UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-MRDC-Capability (if for FR1, the UE supports additional functionality compared to the functionality indicated by the previous field of UE-MRDC-Capability),

[0217] UE 1f-01 may include the fr1-Add-UE-MRDC-Capabilities field in UE-MRDC-Capability and may set the fr1-Add-UE-MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FR1. (Include the field fr1-Add-UE-MRDC-Capabilities and set it to include a field reflecting additional functions applicable to FR1).

[0218] ◇ In case of FR2, when UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-MRDC-Capability (if for FR2, the UE supports additional functionality compared to that indicated by the previous field of UE-MRDC-Capability),

[0219] UE 1f-01 may include the fr2-Add-UE-MRDC-Capabilities field in UE-MRDC-Capability, and may set the fr2-Add-UE-MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FR2. (Include the field fr2-Add-UE-MRDC-Capabilities and set it to include a field reflecting additional functions applicable to FR2).

[0220] *When UE 1f-01 supports both FDD and TDD, and supports one of FR1 and FR2 (in the present disclosure, FRx is used to indicate one of FR1 and FR2) (otherwise, if UE supports both FDD and TDD and a single FRx),

[0221] -UE 1f-01 may set all fields of UE-MRDC-Capability except fdd-Add-UE-MRDC-Capabilities, tdd-Add-UE-MRDC-Capabilities, fr1-Add-UE-MRDC-Capabilities, and fr2-Add-UE-MRDC-Capabilities to include values ​​applicable to FDD, TDD, and FRx (set all fields of UE-MRDC-Capability except fdd-Add-UE-MRDC-Capabilities, tdd-Add-UE-MRDC-Capabilities, fr1-Add-UE-MRDC-Capabilities, and fr2-Add-UE-MRDC-Capabilities to include values ​​applicable to FDD, TDD, and FRx).

[0222] - when some fields of UE-MRDC-Capability have different values ​​for FDD and TDD (if (some) UE capability fields have different values ​​for FDD and TDD),

[0223] ◇ In case of FDD, when UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-MRDC-Capability (if for FDD, the UE supports additional functionality compared to the functionality indicated by the previous field of UE-MRDC-Capability),

[0224] ·UE 1f-01 may include the fdd-Add-UE-MRDC-Capabilities field in UE-MRDC-Capability, and may set the fdd-Add-UE-MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FDD (including the field fdd-Add-UE-MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to FDD).

[0225] ◇ In case of TDD, when UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-MRDC-Capability (if for TDD, the UE supports additional functionality compared to the functionality indicated by the previous field of UE-MRDC-Capability),

[0226] ·UE 1f-01 may include the tdd-Add-UE-MRDC-Capabilities field in UE-MRDC-Capability, and may set the tdd-Add-UE-MRDC-Capabilities field to include a field value reflecting other additional functions applicable to TDD (including the field tdd-Add-UE-MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to TDD).

[0227] *When UE 1f-01 supports one of FDD and TDD (in the present disclosure, xDD is used to indicate one of FDD and TDD), and supports both FR1 and FR2 (otherwise if the UE supports a single xDD mode and both FR1 and FR2),

[0228] -UE 1f-01 may set all fields of UE-MRDC-Capability except fdd-Add-UE-MRDC-Capabilities, tdd-Add-UE-MRDC-Capabilities, fr1-Add-UE-MRDC-Capabilities, and fr2-Add-UE-MRDC-Capabilities to include values ​​applicable to xDD, FR1, and FR2 (set all fields of UE-MRDC-Capability except fdd-Add-UE-MRDC-Capabilities, tdd-Add-UE-MRDC-Capabilities, fr1-Add-UE-MRDC-Capabilities, and fr2-Add-UE-MRDC-Capabilities to include values ​​applicable to xDD, FR1, and FR2).

[0229] - when some fields of UE-MRDC-Capability have different values ​​for FR1 and FR2 (if (some) UE capability fields have different values ​​for FR1 and FR2),

[0230] *227◇In case of FR1, when UE 1f-01 must support additional functionality, compared with the setting of the previous field of UE-MRDC-Capability (if for FR1, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-MRDC-Capability),

[0231] UE 1f-01 may include the fr1-Add-UE-MRDC-Capabilities field in UE-MRDC-Capability, and may set the fr1-Add-UE-MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FR1. (Include the field fr1-Add-UE-MRDC-Capabilities and set it to include a field reflecting additional functions applicable to FR1).

[0232] ◇ In case of FR2, when UE 1f-01 must support additional functionality, compared to the setting of the previous field of UE-MRDC-Capability (if for FR2, the UE supports additional functionality compared to that indicated by the previous field of UE-MRDC-Capability),

[0233] UE 1f-01 may include the fr2-Add-UE-MRDC-Capabilities field in UE-MRDC-Capability, and may set the fr2-Add-UE-MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FR2. (Include the field fr2-Add-UE-MRDC-Capabilities and set it to include a field reflecting additional functions applicable to FR2).

[0234] *When UE 1f-01 supports one of FDD and TDD, and supports one of FR1 and FR2 (otherwise if UE supports single xDD mode and single FRx),

[0235] -UE 1f-01 may set all fields of UE-MRDC-Capability except fdd-Add-UE-MRDC-Capabilities, tdd-Add-UE-MRDC-Capabilities, fr1-Add-UE-MRDC-Capabilities, and fr2-Add-UE-MRDC-Capabilities to include values ​​applicable to xDD and FRx (set all fields of UE-MRDC-Capability except fdd-Add-UE-MRDC-Capabilities, tdd-Add-UE-MRDC-Capabilities, fr1-Add-UE-MRDC-Capabilities, and fr2-Add-UE-MRDC-Capabilities to include values ​​applicable to xDD, FRx).

[0236] 2>UE 1f-01 can include the supported MRDC band combinations in supportedBandCombination.

[0237] 1>UE 1f-01 sends a UECapabilityInformation message to the lower layer to send a UECapabilityInformation message.

[0238] The UE-NR-Capability described above is Figure 1Fb As shown in 1f-03, the UE-MRDC-Capability described above is Figure 1FcIt is shown as 1f-04 in the figure, and information about all parameters can be referenced in "38.331: Radio Resource Control (RRC) Protocol Specification" which is a 3GPP standard specification. In an embodiment of the present disclosure, the process of sending the UECapabilityInformation message can be summarized as follows.

[0239] UE-NR / MRDC-Capability and xxx-Add-UE-NR / MRDC-Capabilities may indicate UE-NR-Capability and / or UE-MRDC-Capability and xxx-Add-UE-NR-Capabilities and / or xxx-Add-UE-MRDC-Capabilities, respectively. (UE-NR / MRDC-Capability and xxx-Add-UE-NR / MRDC-Capabilities mean UE-NR-Capability and / or UE-MRDC-Capability and xxx-Add-UE-NR-Capabilities and / or xxx-Add-UE-MRDC-Capabilities, respectively.)

[0240] 1> When UE 1f-01 supports all of FDD, TDD, FR1 and FR2 (if the UE supports both FDD and TDD and both FR1 and FR2):

[0241] 2>UE 1f-01 may set all fields of UE-NR / MRDC-Capabilities except fdd-Add-UE-NR / MRDC-Capabilities, tdd-Add-UE-NR / MRDC-Capabilities, fr1-Add-UE-NR / MRDC-Capabilities, and fr2-Add-UE-NR / MRDC-Capabilities to include values ​​applicable to FDD, TDD, FR1, and FR2 (set all fields of UE-NR / MRDC-Capabilities except fdd-Add-UE-NR / MRDC-Capabilities, tdd-Add-UE-NR / MRDC-Capabilities, fr1-Add-UE-NR / MRDC-Capabilities, and fr2-Add-UE-NR / MRDC-Capabilities to include values ​​applicable to FDD, TDD, FR1, and FR2);

[0242] 2> When the UE capability field has different values ​​for FDD and TDD (if (some) UE capability fields have different values ​​for FDD and TDD):

[0243] 3> In case of FDD, when UE 1f-01 supports additional functionality, compared with the setting of the previous field of UE-NR / MRDC-Capability (if for FDD, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-NR / MRDC-Capability):

[0244] 4>UE 1f-01 may include an fdd-Add-UE-NR / MRDC-Capabilities field, and may set the fdd-Add-UE-NR / MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FDD (including the field fdd-Add-UE-NR / MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to FDD);

[0245] 3> In case of TDD, when UE 1f-01 supports additional functionality, compared with the setting of the previous field of UE-NR / MRDC-Capability (if for TDD, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-NR / MRDC-Capability):

[0246] 4>UE 1f-01 may include a tdd-Add-UE-NR / MRDC-Capabilities field, and may set the tdd-Add-UE-NR / MRDC-Capabilities field to include a field value reflecting other additional functions applicable to TDD (including the field tdd-Add-UE-NR / MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to TDD);

[0247] 2> When the UE capability field has different values ​​for FR1 and FR2 (if (some) UE capability fields have different values ​​for FR1 and FR2):

[0248] 3> In case of FR1, when UE 1f-01 supports additional functionality, compared with the setting of the previous field of UE-NR / MRDC-Capability (if for FR1, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-NR / MRDC-Capability):

[0249] 4>UE 1f-01 may include a fr1-Add-UE-NR / MRDC-Capabilities field, and may set the fr1-Add-UE-NR / MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FR1 (including the field fr1-Add-UE-NR / MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to FR1);

[0250] 3> In case of FR2, when UE 1f-01 supports additional functionality, compared with the setting of the previous field of UE-NR / MRDC-Capability (if for FR2, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-NR / MRDC-Capability):

[0251] 4>UE 1f-01 may include a fr2-Add-UE-NR / MRDC-Capabilities field, and may set the fr2-Add-UE-NR / MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FR2 (including the field fr2-Add-UE-NR / MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to FR2);

[0252] 1> When UE 1f-01 supports both FDD and TDD and supports a single FRx

[0253] (If UE supports both FDD and TDD and single FRx):

[0254] 2>UE 1f-01 may set all fields of UE-NR / MRDC-Capability except fdd-Add-UE-NR / MRDC-Capabilities, tdd-Add-UE-NR / MRDC-Capabilities, fr1-Add-UE-NR / MRDC-Capabilities, and fr2-Add-UE-NR / MRDC-Capabilities to include values ​​applicable to FDD, TDD, and FRx (set all fields of UE-NR / MRDC-Capability except fdd-Add-UE-NR / MRDC-Capabilities, tdd-Add-UE-NR / MRDC-Capabilities, fr1-Add-UE-NR / MRDC-Capabilities, and fr2-Add-UE-NR / MRDC-Capabilities to include values ​​applicable to FDD, TDD, and FRx);

[0255] 2> When the UE capability field has different values ​​for FDD and TDD (if (some) UE capability fields have different values ​​for FDD and TDD):

[0256] 3> In case of FDD, when UE 1f-01 supports additional functionality, compared with the setting of the previous field of UE-NR / MRDC-Capability (if for FDD, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-NR / MRDC-Capability):

[0257] 4>UE 1f-01 may include an fdd-Add-UE-NR / MRDC-Capabilities field, and may set the fdd-Add-UE-NR / MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FDD (including the field fdd-Add-UE-NR / MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to FDD);

[0258] 3> In case of TDD, when UE 1f-01 supports additional functionality, compared with the setting of the previous field of UE-NR / MRDC-Capability (if for TDD, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-NR / MRDC-Capability):

[0259] 4>UE 1f-01 may include a tdd-Add-UE-NR / MRDC-Capabilities field, and may set the tdd-Add-UE-NR / MRDC-Capabilities field to include a field value reflecting other additional functions applicable to TDD (including the field tdd-Add-UE-NR / MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to TDD);

[0260] 1> When UE 1f-01 supports single xDD mode and supports both FR1 and FR2

[0261] (If UE supports single xDD mode and both FR1 and FR2):

[0262] 2>UE 1f-01 may set all fields of UE-NR / MRDC-Capability except fdd-Add-UE-NR / MRDC-Capabilities, tdd-Add-UE-NR / MRDC-Capabilities, fr1-Add-UE-NR / MRDC-Capabilities, and fr2-Add-UE-NR / MRDC-Capabilities to include values ​​applicable to xDD mode, FR1, and FR2 (set all fields of UE-NR / MRDC-Capabilities except fdd-Add-UE-NR / MRDC-Capabilities, tdd-Add-UE-NR / MRDC-Capabilities, fr1-Add-UE-NR / MRDC-Capabilities, and fr2-Add-UE-NR / MRDC-Capabilities to include values ​​applicable to xDD mode, FR1, and FR2);

[0263] 2> When the UE capability field has different values ​​for FR1 and FR2 (if (some) UE capability fields have different values ​​for FR1 and FR2):

[0264] 3> In case of FR1, when UE 1f-01 supports additional functionality, compared with the setting of the previous field of UE-NR / MRDC-Capability (if for FR1, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-NR / MRDC-Capability):

[0265] 4>UE 1f-01 may include a fr1-Add-UE-NR / MRDC-Capabilities field, and may set the fr1-Add-UE-NR / MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FR1 (including the field fr1-Add-UE-NR / MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to FR1);

[0266] 3> In case of FR2, when UE 1f-01 supports additional functionality, compared with the setting of the previous field of UE-NR / MRDC-Capability (if for FR2, the UE supports additional functionality compared with the functionality indicated by the previous field of UE-NR / MRDC-Capability):

[0267] 4>UE 1f-01 may include a fr2-Add-UE-NR / MRDC-Capabilities field, and may set the fr2-Add-UE-NR / MRDC-Capabilities field to include a field value reflecting other additional functions applicable to FR2 (including the field fr2-Add-UE-NR / MRDC-Capabilities, and set it to include a field reflecting additional functions applicable to FR2);

[0268] 1> When UE 1f-01 supports single xDD mode and single FRx

[0269] (If UE supports single xDD mode and single FRx):

[0270] 2>UE 1f-01 can set all fields of UE-NR / MRDC-Capability except fdd-Add-UE-NR / MRDC-Capabilities, tdd-Add-UE-NR / MRDC-Capabilities, fr1-Add-UE-NR / MRDC-Capabilities and fr2-Add-UE-NR / MRDC-Capabilities to include values ​​applicable to xDD mode and FRx (set all fields of UE-NR / MRDC-Capabilities except fdd-Add-UE-NR / MRDC-Capabilities, tdd-Add-UE-NR / MRDC-Capabilities, fr1-Add-UE-NR / MRDC-Capabilities and fr2-Add-UE-NR / MRDC-Capabilities to include values ​​applicable to xDD mode and FRx).

[0271] Figure 2A A diagram is shown for describing a method of sending and receiving messages between UE2a-01 and gNB2a-03 in order to send a scheduling request according to an embodiment of the present disclosure.

[0272] refer to Figure 2A , UE 2a-01 in idle mode (RRC_IDLE) can perform access to gNB 2a-03 due to the presence of data to be sent (2a-11). Idle mode refers to a state in which UE 2a-01 is not connected to the network in order to save power of UE 2a-01 and therefore cannot send data. For data transmission, UE 2a-01 must transition to connected mode (RRC_CONNECTED). When UE 2a-01 succeeds in the process of accessing gNB 2a-03, UE 2a-01 transitions to connected mode (RRC_CONNECTED). UE 2a-01 in connected mode can be enabled to send data to and receive data from gNB 2a-03 by performing security activation and bearer configuration (to be described below) on the data.

[0273] Thereafter, the gNB 2a-03 may configure a radio bearer (data radio bearer (DRB)) for data transmission, and may send an SR resource and related configuration information for requesting UL resources (2a-13). The DRB indicates a logical channel / path via which wireless data is sent. For example, when each logical channel identifier mapped to each DRB is marked on the subheader of the MAC layer, each of the data packets is sent so that the UE 2a-01 can identify which logical channel / path the corresponding packet belongs to. In addition, as described above, the SR resource is information to be sent via the PUCCH, and the gNB 2a-03 may set multiple periodic SR resources to the UE 2a-01. In the current embodiment of the present disclosure, a regular buffer status report (regular BSR) triggers an SR, and the SR to be sent may be determined based on the content (LCH) reported in the regular BSR. Therefore, when each SR is configured, (multiple) specific logical channels may also be configured with each SR.

[0274] According to the following various conditions, UE 2a-01 can trigger the current BSR of UE 2a-01, and the BSR can be classified based on the conditions that trigger the transmission.

[0275] -Type 1: Regular BSR

[0276] When UE 2a-01 has data that can be sent with respect to a certain logical channel / radio bearer (RB) belonging to a logical channel group (LCG), the BSR is sent when the BSR retransmission timer (retxBSR-Timer) expires.

[0277] The BSR is transmitted when data to be transmitted with respect to a certain logical channel / RB belonging to an LCG is generated in an upper layer (RLC layer or PDCP layer) and has the highest priority over logical channels / RBs belonging to any LCG.

[0278] This BSR is transmitted when data to be transmitted with respect to a certain logical channel / RB belonging to an LCG is generated in an upper layer (RLC layer or PDCP layer) and any LCG has no data except this data.

[0279] -Type 2: Periodic BSR

[0280] This BSR is sent when the periodic BSR timer configured for UE 2a-01 expires.

[0281] - Type 3: Filling BSR

[0282] The BSR is sent when padding bits used to fill unused space occurring after data transmission after UL resources are allocated are equal to or greater than the sum of the size of a BSRMAC Control Element (CE) and the subheader size of the BSRMAC CE.

[0283] When packets exist in the buffers of multiple LCGs, a truncated BSR is sent.

[0284] As described above, when a regular BSR is generated according to the aforementioned conditions, UE 2a-01 can trigger the transmission of an SR through a first SR resource, and then can send the SR. Therefore, in the current embodiment of the present disclosure, when a regular BSR is triggered through an LCH and an SR configuration mapped to the LCH, UE 2a-01 triggers the SR. When the SR is triggered, the SR may be considered pending before the SR is canceled. When a BSR MAC CE (i.e., a control message of the MAC layer) including all buffer statuses of the BSR that triggered the SR is sent to gNB 2a-03, the SR can be canceled. The BSR MAC CE is a control message of the MAC layer, and UE 2a-01 reports the buffer status by using the BSR MAC CE, which includes data to be sent to gNB 2a-03 via the UL. For example, a scenario can be assumed in which gNB 2a-03 configures three SRs to UE 2a-01, and SR#1 is mapped to LCH x and LCH y, and SR#2 is mapped to LCH z. Assuming that LCH x, LCH y and LCH z have the first, second and third priorities respectively, when traffic only exists on LCH z in the buffer (and then data appears on LCHy, a regular BSR is triggered due to LCH y, so SR#1 can be triggered.

[0285] The RRC configuration message may include information about at least one of time / frequency / code / parameter set (subcarrier spacing) / transmission time interval (TTI) length of SR transmission according to each SR resource, and information about the LCH mapped to each SR resource.

[0286] gNB 2a-03 may send various measurement configurations to UE 2a-01 by using the RRCReconfiguration message of the RRC layer. Afterwards, UE 2a-01 sends a confirmation message (2a-15) about the configuration, for which the RRCReconfigurationComplete message of the RRC layer may be used.

[0287] As described above, it can be assumed that gNB 2a-03 configures three SRs to UE 2a-01, and SR#1 is mapped to LCH x and LCH y, and SR#2 is mapped to LCH z. In this regard, it is assumed that LCH x, LCH y, and LCH z have the first, second, and third priorities, respectively.

[0288] Later, when traffic exists only on LCH z in the buffer and then data appears on LCH y, a regular BSR is triggered due to LCH y (2a-17), so a pending SR may occur with respect to SR#1 (2a-19).

[0289] Therefore, when each sr-ProhibitTimer set to each SR configuration according to each SR configuration associated with (multiple) pending SRs is not running, UE 2a-01 can send SR (2a-21) to gNB 2a-03 through PUCCH resources configured for each SR configuration, and can start sr-ProhibitTimer set to the corresponding SR configuration. When the SR associated with the pending SR does not exist, UE 2a-01 can perform random access to send a preamble directly to gNB 2a-03.

[0290] In the aforementioned example, later, when data is newly generated in LCH x, a regular BSR is triggered due to LCH x (2a-27), and thus a pending SR may additionally occur with respect to SR#1 (2a-29). That is, two pending SRs may exist with respect to SR#1.

[0291] However, because the sr-ProhibitTimer is already running with respect to SR#1, UE 2a-01 may not send the SR before the sr-ProhibitTimer with respect to SR#1 expires (2a-25).

[0292] UE 2a-01 checks the following conditions for each SR configuration. That is, in the current embodiment of the present disclosure, two pending SRs belong to one SR#1, and therefore, UE 2a-01 may perform the following operation only once, instead of twice.

[0293] -UE 2a-01 is checking whether there is a PUCCH resource in the corresponding SR configuration.

[0294] -Set to the case where the sr-ProhibitTimer configured for the corresponding SR is not running.

[0295] * The case where the PUCCH resources configured by 292-SR do not overlap with the measurement gap used for measurement of neighboring cells.

[0296] -The case where the PUCCH resources configured for SR do not overlap with the resources used for data transmission.

[0297] When the aforementioned conditions are all met, UE 2a-01 may increase SR_COUNTER by 1, may instruct the physical layer to send PUCCH resources, and thus may send SR (2a-31), and may then restart sr-ProhibitTimer.

[0298] Thereafter, when UL resources are allocated from gNB 2a-03 (2a-33), UE 2a-01 may send BSR MAC CE (2a-35) through the corresponding resources. When BSR MAC CE includes all buffer statuses when the second regular BSR is triggered, UE 2a-01 may cancel all two pending SRs. However, when BSR MAC CE includes only the buffer statuses when the first regular BSR is triggered, UE 2a-01 may cancel only SR#1 without canceling SR#2, and make SR#2 pending. By doing so, when sr-ProhibitTimer expires later, UE 2a-01 may additionally send an SR.

[0299] Figure 2B A flowchart for describing the operation of a UE when sending a scheduling request according to an embodiment of the present disclosure is shown.

[0300] exist Figure 2B In the embodiment, it is assumed that the UE is connected to the LTE BS and is therefore in the RRC_CONNECTED state (2b-01). Thereafter, the UE may be configured for DRBs from the BS, may be configured for SR resources and related configuration information for requesting UL resources from the BS, and may send a confirmation message in response to the configuration (2b-03).

[0301] As described above, the UE may trigger the current BSR of the UE according to the following various conditions, and the BSR may be classified based on the conditions triggering the transmission.

[0302] -Type 1: Regular BSR

[0303] Condition 1: When UE 2a-01 has data that can be sent with respect to a certain logical channel / RB belonging to the LCG, the BSR is sent when the BSR retransmission timer expires.

[0304] Condition 2: This BSR is sent when data to be sent with respect to a certain logical channel / RB belonging to an LCG is generated in an upper layer (RLC layer or PDCP layer) and the data has the highest priority higher than logical channels / RBs belonging to any LCG.

[0305] Condition 3: This BSR is sent when data to be sent with respect to a certain logical channel / RB belonging to an LCG is generated in an upper layer (RLC layer or PDCP layer) and no LCG has data other than this data.

[0306] -Type 2: Periodic BSR

[0307] This BSR is sent when the periodic BSR timer configured for UE 2c-01 expires.

[0308] - Type 3: Filling BSR

[0309] The BSR is sent when the padding bits used to fill the unused space occurring after data transmission after UL resources are allocated are equal to or greater than the sum of the size of the BSR MAC CE and the subheader size of the BSR MAC CE.

[0310] When packets exist in the buffers of multiple LCGs, a truncated BSR is sent.

[0311] At this point, the UE can determine whether a regular BSR is triggered because the traffic appears in a logical channel configured from among all logical channels (or when the traffic remains unchanged when the retxBSR-Timer expires) (2b-05).

[0312] When a regular BSR is triggered, the UE may trigger an SR and may determine whether there are configured PUCCH SR resources in the triggered SR (2b-07). When the configured PUCCH SR resources do not exist in the triggered SR, the UE may perform random access and may then send a BSR MAC CE (2b-15).

[0313] When the configured PUCCH SR resource exists in the triggered SR (i.e., when the SR configuration mapped to the triggered and then pending SR exists), the UE may check the following conditions for each SR configuration. That is, in the current embodiment of the present disclosure, two pending SRs belong to one SR#1, and therefore, the following operation may be performed only once, not twice.

[0314] - Check whether there are PUCCH resources in the corresponding SR configuration.

[0315] -Set to the case where the sr-ProhibitTimer configured for the corresponding SR is not running.

[0316] - The case where the PUCCH resources configured by SR do not overlap with the measurement gaps used for measurement of neighboring cells.

[0317] -The case where the PUCCH resources configured for SR do not overlap with the resources used for data transmission.

[0318] When the foregoing conditions are met, the UE may determine whether the number of SR transmissions is less than the maximum number of SR transmissions allowed (sr_TransMax), and when the number of SR transmissions is less than the maximum number of SR transmissions allowed (sr_TransMax), the UE may increase the SR_COUNTER by 1, may send an SR (2b-09) by instructing the physical layer to send PUCCH resources, and may restart the sr-ProhibitTimer. When the number of SR transmissions reaches the maximum number of SR transmissions allowed, the UE may perform the following operations.

[0319] -Notify the RRC layer about the release of PUCCH resources of all serving cells;

[0320] -Notify the RRC layer about the release of SRS resources of all serving cells;

[0321] - Remove the configured DL allocation and UL allocation information;

[0322] - Release PUSCH resources used for reporting semi-persistent CSI; and

[0323] - When a SR is sent to the MCG, a random access is performed on the PCell, and when a SR is sent to the SCG, a random access is performed on the PSCell, and then all pending SRs are canceled.

[0324] Afterwards, the UE may determine whether UL resources are allocated from the BS (2b-11), and when no UL resources are allocated, the sr-ProhibitTimer does not run, and when the number of SR transmissions does not reach the maximum number of SR transmissions allowed (2b-13), the UE may retransmit the SR (2b-09). When the number of SR transmissions reaches the maximum number of SR transmissions allowed (2b-13), the UE may send a BSR MAC CE by performing random access (2b-15).

[0325] When the UE receives the UL resource, the UE may send a BSR MAC CE (2b-17) through the UL resource. In addition, when the BSR MAC CE includes all buffer states when the second regular BSR is triggered, the UE may cancel all two pending SRs. However, when the BSR MAC CE includes only the buffer state when the first regular BSR is triggered, the UE may cancel only the first SR, and may not cancel the second SR, and make the second SR pending. By doing so, when the sr-ProhibitTimer expires thereafter, the UE may additionally send the second SR.

[0326] Figure 3A A diagram is shown for describing DL and UL channel frame structures for beam-based communication performed in an NR system according to an embodiment of the present disclosure.

[0327] refer to Figure 3A , BS 3a-01 may transmit signals in the form of beams 3a-11, 3a-13, 3a-15, and 3a-17 for wider coverage or strong signaling. Therefore, UE 3a-03 in the cell may need to use a specific beam (in Figure 3A In the example, beam #1 3a-13) is used to send or receive data.

[0328] Depending on whether UE 3a-03 is connected to BS 3a-01, UE 3a-03 can be classified as being in RRC idle mode, RRC inactive mode or RRC connected mode. Therefore, when UE 3a-03 is in RRC inactive mode, BS 3a-01 may not know where UE 3a-03 is.

[0329] When UE 3a-03 attempts to transition from RRC inactive mode to RRC connected mode, UE 3a-03 can receive synchronization signal blocks (SSBs) 3a-21, 3a-23, 3a-25 and 3a-27 sent from BS 3a-01. The SSB can be an SSB signal periodically sent at a specific interval set by BS 3a-01, and each SSB may include a primary synchronization signal (PSS) 3a-41, a secondary synchronization signal (SSS) 3a-43 and a physical broadcast channel (PBCH) 3a-45.

[0330] Figure 3A For example, assume that beam #0 3a-11 is used to transmit SSB #0 3a-21, beam #1 3a-13 is used to transmit SSB #1 3a-23, beam #2 3a-15 is used to transmit SSB #2 3a-25, and beam #3 3a-17 is used to transmit SSB #3 3a-27. Assume that UE 3a-03 in RRC idle mode or RRC inactive mode is located Figure 3A3a-13 in the beam #1 3a-13, therefore, UE 3a-03 receives SSB#1 3a-23 transmitted by beam #1 3a-13. When UE 3a-03 receives SSB#1 3a-23, UE 3a-03 can obtain the physical cell identifier (PCI) of BS 3a-01 from the PSS or SSS, and when UE 3a-03 receives PBCH, UE 3a-03 can know the identifier of the currently received SSB (e.g., SSB#1), where the SSB is located in the 10ms frame, and which SFN among the system frame numbers (SFNs) the SSB is located in within the 10.24ms period.

[0331] In addition, the PBCH may include a master information block (MIB), and the MIB may include information indicating the location of a system information block type 1 (SIB1) where more detailed configuration information of the broadcast cell may be received. When the UE 3a-03 receives the SIB1, the UE 3a-03 may know the total number of SSBs transmitted by the BS 3a-01, and a physical random access channel (PRACH) timing (e.g., a preamble as a physical signal designed to be synchronized with UL transmission) used to perform random access on the BS 3a-01 to transition to an RRC connected mode (more specifically, to transmit a physical random access channel (PRACH)). Figure 3A 3a-30 to 3a-39, which are allocated at intervals of 1 ms). In addition, based on the information of SIB1, UE 3a-03 can determine which PRCH opportunity is mapped to which SSB index. For example, Figure 3A In FIG. 1 , it is assumed that the PRACH opportunities are allocated at intervals of 1 ms as described above, and 1 / 2 SSB is allocated for each PRACH opportunity (ie, two PRACHs per SSB). Therefore, Figure 3A A scenario is shown in which two PRACH opportunities are allocated for each SSB starting from a PRACH opportunity starting with SFN. For example, PRACH opportunities 3a-30 and 3a-31 may be allocated for SSB#0, and PRACH opportunities 3a-32 and 3a-33 may be allocated for SSB#1. After configuring PRACH opportunities for all SSBs, subsequent PRACH opportunities 3a-38 and 3a-39 may be allocated for the first SSB.

[0332] Therefore, UE 3a-03 can identify the positions of PRACH opportunities 3a-32 and 3a-33 of SSB#1, and can therefore send a random access preamble at the earliest PRACH opportunity 3a-32 at the current time point among PRACH opportunities 3a-32 and 3a-33 corresponding to SSB#1. Because BS 3a-01 receives the preamble at PRACH opportunity 3a-32, BS 3a-01 can determine that UE3a-03 selected SSB#1 and sent the preamble, and can send or receive data through the beam corresponding to SSB#1 when performing subsequent random access.

[0333] Figure 3B A diagram for describing a cell reselection procedure in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to an embodiment of the present disclosure is shown.

[0334] The cell reselection process indicates the process by which a UE in RRC idle mode or RRC inactive mode determines whether to maintain the current serving cell or reselect a cell as a neighboring cell when the service quality of the serving cell deteriorates due to a predetermined reason or due to the movement of the UE compared to the service quality of a neighboring cell. In handover, whether to perform handover is determined by the network (MME, access and mobility management function (AMF), source eNB or source gNB), while in the cell reselection process, the UE itself can determine whether to perform the cell reselection process based on the measurement values ​​of the UE. The cell to be reselected by the UE when the UE moves can be an intra-frequency cell using the same NR frequency as the serving cell where the UE is currently residing, an inter-frequency cell using a different NR frequency, or an inter-radio access technology (inter-RAT) cell using a different RAT.

[0335] A UE in an RRC idle mode or an RRC inactive mode (operation 3b-01) may perform a series of operations while it camps on a serving cell (operation 3b-05).

[0336] In operation 3b-10, a UE in RRC idle mode or RRC inactive mode may receive system information broadcast by a BS of a serving cell. In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by a BS of a neighboring cell. System information may be divided into a master information block (MIB) and a system information block (SIB). In addition, SIB may be divided into SIB1 and SI messages (e.g., SIB2, SIB3, SIB4, SIB5, SIB6, SIB7, SIB8, or SIB9) that do not include SIB1. A UE in RRC idle mode or RRC inactive mode may pre-receive and read system information (e.g., MIB or SIB1) broadcast by a base station of a serving cell before the UE resides in a serving cell. For reference, MIB and SIB1 may be system information to be commonly applied to all UEs. SIB2 may be system information to be commonly applied by UEs in RRC idle mode or RRC inactive mode to the process of reselecting a same-frequency cell, a different-frequency cell, or a different RAT cell. SIB3, SIB4 and SIB5 may include information required for a UE in RRC idle mode or RRC inactive mode to reselect a cell.

[0337] SIB1 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a serving cell signal, and such information may be applied in a cell-specific manner. SIB2, SIB3, SIB4, and SIB5 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a neighboring cell signal. In detail, SIB2 may include common information for reselecting a same-frequency cell, a different-frequency cell, or a different-RAT cell, SIB3 may include information for reselecting only a same-frequency cell, SIB4 may include information for reselecting only a different-frequency cell, and SIB5 may include information for reselecting only a different-RAT cell.

[0338] In operation 3b-15, a UE in RRC idle mode or RRC inactive mode may wake up in a discontinuous reception (DRX) period and may measure a reference signal received power (RSRP) Qrxlevmeas and a reference signal received quality (RSRQ) Qqualmeas (operation 3b-15). The UE may calculate a reception level Srxlev and a reception quality Squal of a serving cell based on the measured values ​​by using parameters received from SIB1. The UE may compare the calculated value with a threshold value and may then determine whether to perform neighboring cell measurements for cell reselection. The reception level Srxlev and the reception quality Squal of a serving cell may be determined by using the following equation 1.

[0339] <Equation 1>

[0340] Srxlev=Qrxlevmeas-(Qrxlevmin+Qrxlevminoffset)-Pcompensation-Qoffsettemp,

[0341] Squal=Qqualmeas-(Qqualmin+Qqualminoffset)-Qoffsettemp.

[0342] The definition of the parameters used in Equation 1 may be determined according to the 3GPP standard specification entitled “38.304: User Equipment (UE) Procedures in Idle Mode and RRC Inactive State.” Hereinafter, the definition also applies to the embodiments of the present disclosure to which Equation 1 is applied.

[0343] A UE in RRC idle mode or RRC inactive mode may not continuously perform neighbor cell measurements, but may determine whether to perform neighbor cell measurements based on measurement rules in order to minimize battery power consumption (operation 3b-20). In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by the BS of a neighboring cell, and may perform neighbor cell measurements by using system information broadcast by the serving cell where the UE is currently residing. When the reception level Srxlev and reception quality Squal of the serving cell measured in operation 3b-15 are lower than a threshold value (Srxlev≤SintraSearchP and Squal≤SIntraSearchQ), the UE in RRC idle mode or RRC inactive mode may measure the same frequency cell using the same frequency as the serving cell (operation 3b-20). That is, the reception quality Squal or reception level Srxlev of each same frequency cell using the same frequency as the serving cell may be derived based on SIB2 or / and SIB3 broadcast by the serving cell (application of equation 1).

[0344] For reference, information about the thresholds SIntraSearchP and SIntraSearchQ is included in SIB2. In addition, regardless of the quality of the serving cell, neighbor cell measurements can be performed on inter-frequency and inter-RAT cells having a higher priority than the frequency of the current serving cell (operation 3b-20). The UE can obtain information about priority from a dedicated RRC message (e.g., RRC Release message) or system information from the BS. The reception quality Squal or reception level Srxlev of each inter-frequency cell having a higher priority than the frequency of the serving cell can be derived based on SIB4 broadcast by the serving cell (according to Equation 1), and the reception quality Squal or reception level Srxlev of each inter-RAT cell having a higher priority than the frequency of the serving cell can be derived based on SIB5 broadcast by the serving cell (according to Equation 1). In addition, for an inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell, or for an inter-RAT cell having a frequency lower than the frequency of the serving cell, when the reception level Srxlev and the reception quality Squal of the serving cell measured in operation 3b-15 are lower than the threshold value (Srxlex≤SnonIntraSearchP and Squal≤SintraSearchQ), the UE in RRC idle mode or RRC inactive mode can measure the neighboring inter-frequency cell using a frequency different from the serving cell, or measure the neighboring inter-RAT cell using a RAT different from the serving cell (3b-20). That is, the reception quality Squal or the reception level Srxlev of at least one inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell is derived based on SIB4 broadcasted by the serving cell (according to Equation 1), and the reception quality Squal or the reception level Srxlev of at least one inter-RAT cell having a frequency lower than the frequency of the serving cell is derived based on SIB5 broadcasted by the serving cell (according to Equation 1). For reference, information about the thresholds SnonIntraSearchP and SnonIntraSearchQ is included in SIB2.

[0345] A UE in RRC idle mode or RRC inactive mode may perform a cell reselection evaluation process (3b-25) based on cell reselection priority and / or ranking, based on the measurement values ​​of neighboring cells (obtained in 3b-20). That is, when multiple cells that meet the cell reselection criteria have different priorities, the reselection of a frequency / RAT cell with a higher priority precedes the reselection of a frequency / RAT cell with a lower priority (if multiple cells of different priorities meet the cell reselection criteria, the cell reselection for a higher priority RAT / frequency should precede the RAT / frequency with a lower priority). Priority information is included in the system information (SIB2, SIB4, and SIB5) broadcast by the serving cell, or is included in the RRCRelease message received when the UE transitions from RRC connected mode to RRC idle mode or RRC inactive mode. The information about priority included in the RRCRelease message may have priority over the information about priority included in the system information broadcast by the serving cell. The operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a higher priority than the frequency of the serving cell will now be described below.

[0346] -First operation:

[0347] *When SIB2 including the threshold threshServingLowQ is broadcast and 1 second has passed after the UE resides in the current serving cell, when the reception quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighQ during a specific time interval TreselectionRAT (Squal>ThreshX during the time interval TreselectionRAT), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0348] - Second operation:

[0349] *When the UE cannot perform the first operation, the UE may perform the second operation.

[0350] *When 1 second has passed after the UE camps on the current serving cell and the reception level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighP during a specific time interval TreselectionRAT (During the time interval TreselectionRAT, Srxlev>ThreshX,HighP), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0351] In this regard, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-frequency cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB4 broadcast by the serving cell). In addition, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-RAT cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB5 broadcast by the serving cell).

[0352] Furthermore, the operation of a ranking-based cell reselection evaluation procedure of the UE for an intra-frequency cell belonging to the frequency of the current serving cell or an inter-frequency cell having a priority equal to the frequency of the current serving cell will now be described below.

[0353] -Third operation:

[0354] *When the reception quality Squal and reception level Srxlev of each intra-frequency / inter-frequency cell are greater than 0, the UE can derive the ranking of each cell based on the measurement value of RSRP (the UE should perform ranking on all cells that meet the cell selection criterion S). The ranking of the serving cell and the neighboring cell can be calculated separately by using the following equation 2.

[0355] <Equation 2>

[0356] Rs=Qmeas,s+Qhyst

[0357] Rn=Qmeas,n-Qoffset

[0358] *In Equation 2, Qmeas,s indicates the RSRP measurement value of the serving cell, Qmeas,n indicates the RSRP measurement value of the neighboring cell, Qhyst indicates the hysteresis value of the serving cell, and Qoffset indicates the offset between the serving cell and the neighboring cell. SIB2 includes the Qhyst value, and the Qhyst value can be used together to reselect the same-frequency / inter-frequency cell. When reselecting the same-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB3. When reselecting the inter-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB4. When the ranking of the neighboring cell derived from Equation 2 is greater than the ranking of the serving cell (i.e., Rn>Rs), the UE can reside in the best cell among the neighboring cells.

[0359] In addition, the operation of the UE for the cell reselection evaluation process of a different-frequency / different RAT cell with a lower priority than the frequency of the current serving cell will now be described below.

[0360] *357 - Fourth operation:

[0361] *When SIB2 including the threshold threshServingLowQ is broadcast and 1 second has elapsed after the UE camps on the current serving cell, when the received quality Squal of the current serving cell is less than the threshold ThreshServing,LowQ (Squal < ThreshServing,LowQ), and the received quality Squal of the different-frequency or different RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Squal > ThreshX,LowQ), the UE can perform reselection for the different-frequency or different RAT cell.

[0362] - Fifth operation:

[0363] *When the UE cannot perform the fourth operation, the UE can perform the fifth operation.

[0364] *When 1 second has elapsed after the UE camps on the current serving cell, the received level Srxlev of the current serving cell is lower than the threshold ThreshServing,LowP (Srxlev < ThreshServing,LowP), and the received level Srxlev of the different-frequency or different RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Srxlev > ThreshX,LowP), then the UE can perform reselection for the different-frequency or different RAT cell.

[0365] In this regard, the fourth operation or the fifth operation of the UE for the inter-frequency cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the reception quality Squal, reception level Srxlev and thresholds ThreshX,LowQ and ThreshX,LowP of the inter-frequency cell included in SIB4 broadcast by the serving cell. The fourth operation or the fifth operation of the UE for the inter-RAT cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the reception quality Squal, reception level Srxlev and thresholds ThreshX,LowQ and ThreshX,LowP of the inter-RAT cell included in SIB5 broadcast by the serving cell. For example, SIB4 includes a Qqualmin value or a Qrxlevmin value, and the reception quality Squal or reception level Srxlev of the inter-frequency cell may be derived based on the value.

[0366] In 3b-30, the UE may derive a candidate cell list, and then may select a candidate target cell based on a priority and / or ranking from the candidate cell list. When selecting a candidate target cell, in 3b-35, the UE in RRC idle mode or RRC inactive mode may determine whether to select the corresponding cell by attempting to receive the MIB and SIB1 broadcast by the corresponding cell before the UE finally selects the corresponding cell. At this time, the UE performs the following operations.

[0367] When the selected candidate target cell broadcasts the MIB in 3b-35, the UE may attempt to receive the MIB in 3b-40.

[0368] When the UE cannot obtain the MIB, the UE may perform the sixth operation in 3b-45.

[0369] Sixth operation: The UE may consider the cell state of the corresponding cell to be barred, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds (the UE shall or may exclude the barred cell as a candidate for cell selection / reselection within up to 300 seconds). When the reception quality Squal and / or reception level Srxlev of another cell (the other cell uses the same frequency as the corresponding cell) derived according to Equation 1 is greater than 0 and / or satisfies the cell reselection criteria, the UE may select the other cell (if the selection criteria and / or cell reselection criteria are met, the UE may select another cell on the same frequency).

[0370] When the UE receives the MIB (upon receiving the MIB), the UE may determine whether the corresponding cell satisfies the first condition or the second condition based on information included in the MIB (3b-50).

[0371] First condition: when a cellBarred field value included in the received MIB is set to 'barred' and / or PDCCH-ConfigSIB1 is not supported.

[0372] Second condition: a condition that does not correspond to the first condition

[0373] Seventh operation: When the first condition is met, in 3b-55, the UE may consider the corresponding cell as a prohibited cell, and may exclude the prohibited cell from the candidate cell list for cell selection / reselection within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells that use the same frequency as the prohibited cell within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "allowed", when the (multiple) cells meet the cell reselection criteria, the UE may select the (multiple) cells, and the (multiple) cells use the same frequency as the prohibited cell.

[0374] Eighth operation: When the second condition is met, in 3b-60, the UE may consider the corresponding cell as an allowed cell, and may determine the corresponding cell as a candidate cell for cell selection / reselection. When the intraFreqReselection field value included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells using the same frequency as the cell within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "allowed", when the (multiple) cell meets the cell reselection criteria, the UE may select the (multiple) cell, and the (multiple) cell uses the same frequency as the cell.

[0375] When the selected candidate target cell broadcasts SIB1 in 3b-35, the UE may attempt to receive SIB1 in 3b-65.

[0376] When the UE cannot obtain SIB1, the UE may perform the seventh operation described in 3b-55 in 3b-70.

[0377] When the UE receives SIB1 (upon receiving SIB1), the UE may determine whether the corresponding cell satisfies the third condition or the fourth condition (3b-75) based on the information included in SIB1. The third condition and the fourth condition are as follows.

[0378] Third condition: When the UE identifies the FrequencyInfoDL-SIB included in the received SIB1 and does not support the bandwidth of all subcarrier spacings (SCS) in scs-SpecificCarrierList

[0379] Fourth condition: When the UE identifies the FrequencyInfoDL-SIB included in the received SIB1 and supports the bandwidth of at least one SCS in the scs-SpecificCarrierList (if the UE supports the bandwidth of at least one SCS in the scs-SpecificCarrierList in the FrequencyInfoDL-SIB in SIB1)

[0380] Ninth operation: When the third condition is met, in 3b-80, the UE may determine that the corresponding cell is inaccessible or may consider the corresponding cell to be a prohibited cell, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds. The UE may not select / reselect a cell(s) using the same frequency as the prohibited cell within 300 seconds.

[0381] Tenth operation: When the fourth condition is met, in 3b-85, the UE may determine that the corresponding cell is accessible. Then, the UE may derive the reception quality Squal and / or the reception level Srxlev of the corresponding cell based on the information included in SIB1 by using equation 1, and when the reception quality Squal and / or the reception level Srxlev satisfies the S criterion (Srxlev>0 and / or Squal>0), the UE may finally reselect the corresponding cell, otherwise, the UE may not finally reselect the corresponding cell.

[0382] Figure 3C A diagram for describing a cell reselection procedure in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown.

[0383] A UE in RRC idle mode or RRC inactive mode (operation 3c-01) may perform a series of operations while it resides in a serving cell (operation 3c-05).

[0384] In operation 3c-10, a UE in RRC idle mode or RRC inactive mode may receive system information broadcast by a BS of a serving cell. In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by a BS of a neighboring cell. System information may be divided into a master information block (MIB) and a system information block (SIB). In addition, SIB may be divided into SIB1 and SI messages (e.g., SIB2, SIB3, SIB4, SIB5, SIB6, SIB7, SIB8, or SIB9) that do not include SIB1. A UE in RRC idle mode or RRC inactive mode may pre-receive and read system information (e.g., MIB or SIB1) broadcast by a base station of a serving cell before the UE resides in a serving cell. For reference, MIB and SIB1 may be system information to be commonly applied to all UEs. SIB2 may be system information to be commonly applied by a UE in RRC idle mode or RRC inactive mode to the process of reselecting a same-frequency cell, a different-frequency cell, or a different RAT cell. SIB3, SIB4 and SIB5 may include information required for a UE in RRC idle mode or RRC inactive mode to reselect a cell.

[0385] SIB1 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a serving cell signal, and such information may be applied in a cell-specific manner. SIB2, SIB3, SIB4, and SIB5 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a neighboring cell signal. In detail, SIB2 may include common information for reselecting a same-frequency cell, a different-frequency cell, or a different-RAT cell, SIB3 may include information for reselecting only a same-frequency cell, SIB4 may include information for reselecting only a different-frequency cell, and SIB5 may include information for reselecting only a different-RAT cell.

[0386] In operation 3c-15, a UE in RRC idle mode or RRC inactive mode may wake up in a discontinuous reception (DRX) period and may measure a reference signal received power (RSRP) Qrxlevmeas and a reference signal received quality (RSRQ) Qqualmeas (operation 3c-15). The UE may calculate the reception level Srxlev and reception quality Squal of the serving cell based on the measured values ​​by using the parameters received from SIB1. The UE may compare the calculated value with a threshold value and may then determine whether to perform neighboring cell measurements for cell reselection. The reception level Srxlev and reception quality Squal of the serving cell may be determined by using the above equation 1.

[0387] A UE in RRC idle mode or RRC inactive mode may not continuously perform neighbor cell measurements, but may determine whether to perform neighbor cell measurements based on measurement rules in order to minimize battery power consumption (operation 3c-20). In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by the BS of a neighboring cell, and may perform neighbor cell measurements by using system information broadcast by the serving cell where the UE is currently residing. When the reception level Srxlev and reception quality Squal of the serving cell measured in operation 3c-15 are lower than a threshold value (Srxlev≤SintraSearchP and Squal≤SIntraSearchQ), the UE in RRC idle mode or RRC inactive mode may measure the same frequency cell using the same frequency as the serving cell (operation 3c-20). That is, the reception quality Squal or reception level Srxlev of each same frequency cell using the same frequency as the serving cell may be derived based on SIB2 or / and SIB3 broadcast by the serving cell (application of equation 1).

[0388] For reference, information about the thresholds SIntraSearchP and SIntraSearchQ is included in SIB2. In addition, regardless of the quality of the serving cell, neighbor cell measurements can be performed on inter-frequency and inter-RAT cells having a higher priority than the frequency of the current serving cell (operation 3c-20). The UE can obtain information about priority from a dedicated RRC message (e.g., RRC Release message) or system information from the BS. The reception quality Squal or reception level Srxlev of each inter-frequency cell having a higher priority than the frequency of the serving cell can be derived based on SIB4 broadcast by the serving cell (according to Equation 1), and the reception quality Squal or reception level Srxlev of each inter-RAT cell having a higher priority than the frequency of the serving cell can be derived based on SIB5 broadcast by the serving cell (according to Equation 1). In addition, for an inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell, or for an inter-RAT cell having a frequency lower than the frequency of the serving cell, when the reception level Srxlev and the reception quality Squal of the serving cell measured in operation 3c-15 are lower than the threshold value (Srxlex≤SnonIntraSearchP and Squal≤SintraSearchQ), the UE in RRC idle mode or RRC inactive mode can measure the neighboring inter-frequency cell using a frequency different from the serving cell, or measure the neighboring inter-RAT cell using a RAT different from the serving cell (3c-20). That is, the reception quality Squal or the reception level Srxlev of at least one inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell is derived based on SIB4 broadcast by the serving cell (according to Equation 1), and the reception quality Squal or the reception level Srxlev of at least one inter-RAT cell having a frequency lower than the frequency of the serving cell is derived based on SIB5 broadcast by the serving cell (according to Equation 1). For reference, information about the thresholds SnonIntraSearchP and SnonIntraSearchQ is included in SIB2.

[0389] A UE in RRC idle mode or RRC inactive mode can perform a cell reselection evaluation process (3c-25) based on cell reselection priority and / or ranking, based on the measurement values ​​of neighboring cells (obtained in 3c-20). That is, when multiple cells that meet the cell reselection criteria have different priorities, the reselection of a frequency / RAT cell with a higher priority precedes the reselection of a frequency / RAT cell with a lower priority (if multiple cells of different priorities meet the cell reselection criteria, the cell reselection for a higher priority RAT / frequency should precede the RAT / frequency with a lower priority). Priority information is included in the system information (SIB2, SIB4 and SIB5) broadcast by the serving cell, or is included in the RRCRelease message received when the UE transitions from RRC connected mode to RRC idle mode or RRC inactive mode. The information about priority included in the RRCRelease message may have priority over the information about priority included in the system information broadcast by the serving cell. The operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a higher priority than the frequency of the serving cell will now be described below.

[0390] -First operation:

[0391] *When SIB2 including the threshold threshServingLowQ is broadcast and 1 second has passed after the UE resides in the current serving cell, when the reception quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighQ during a specific time interval TreselectionRAT (Squal>ThreshX during the time interval TreselectionRAT), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0392] - Second operation:

[0393] *When the UE cannot perform the first operation, the UE may perform the second operation.

[0394] *When 1 second has passed after the UE camps on the current serving cell and the reception level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighP during a specific time interval TreselectionRAT (During the time interval TreselectionRAT, Srxlev>ThreshX,HighP), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0395] In this regard, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-frequency cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB4 broadcast by the serving cell). In addition, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-RAT cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB5 broadcast by the serving cell).

[0396] Furthermore, the operation of a ranking-based cell reselection evaluation procedure of the UE for an intra-frequency cell belonging to the frequency of the current serving cell or an inter-frequency cell having a priority equal to the frequency of the current serving cell will now be described below.

[0397] -Third operation:

[0398] *When the reception quality Squal and reception level Srxlev of each intra-frequency / inter-frequency cell are greater than 0, the UE can derive the ranking of each cell based on the measurement value of RSRP (the UE should perform ranking on all cells that meet the cell selection criterion S). The ranking of the serving cell and the neighboring cell can be calculated separately by using the above equation 2.

[0399] In the aforementioned equation 2, Qmeas,s indicates the RSRP measurement value of the serving cell, Qmeas,n indicates the RSRP measurement value of the neighboring cell, Qhyst indicates the hysteresis value of the serving cell, and Qoffset indicates the offset between the serving cell and the neighboring cell. SIB2 includes the Qhyst value, and the Qhyst value can be used together to reselect the same-frequency / different-frequency cells. When reselecting the same-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB3. When reselecting the different-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB4. When the ranking of the neighboring cell derived according to equation 2 is greater than the ranking of the serving cell (i.e., Rn>Rs), the UE can reside in the best cell among the neighboring cells.

[0400] Furthermore, the operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a lower priority than the frequency of the current serving cell will now be described below.

[0401] *398-Fourth Operation:

[0402] *When the UE broadcasts SIB2 including the threshold threshServingLowQ and 1 second has elapsed after the UE camps on the current serving cell, when the received quality Squal of the current serving cell is less than the threshold ThreshServing,LowQ (Squal < ThreshServing,LowQ), and the received quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Squal > ThreshX,LowQ), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0403] - Fifth operation:

[0404] *When the UE cannot perform the fourth operation, the UE may perform the fifth operation.

[0405] *When 1 second has elapsed after the UE camps on the current serving cell, the received level Srxlev of the current serving cell is lower than the threshold ThreshServing,LowP (Srxlev < ThreshServing,LowP), and the received level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Srxlev > ThreshX,LowP), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0406] In this regard, the fourth or fifth operation of the UE for the inter-frequency cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-frequency cell and the thresholds ThrehX,LowQ and ThreshX,LowP included in SIB4 broadcast by the serving cell. The fourth or fifth operation of the UE for the inter-RAT cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-RAT cell and the thresholds ThreshX,LowQ and ThreshX,LowP included in SIB5 broadcast by the serving cell. For example, SIB4 includes the Qqualmin value or the Qrxlevmin value, and the received quality Squal or received level Srxlev of the inter-frequency cell may be derived based on this value.

[0407] In 3c-30, the UE may derive a candidate cell list, and then may select a candidate target cell based on the priority and / or ranking from the candidate cell list. When selecting a candidate target cell, in 3c-35, the UE in RRC idle mode or RRC inactive mode may determine whether to select the corresponding cell by attempting to receive the MIB and SIB1 broadcast by the corresponding cell before the UE finally selects the corresponding cell. At this time, the UE performs the following operations.

[0408] When the selected candidate target cell broadcasts the MIB in 3c-35, the UE may attempt to receive the MIB in 3c-40.

[0409] When the UE cannot obtain the MIB, the UE may perform the sixth operation in 3c-45.

[0410] Sixth operation: The UE may consider the cell state of the corresponding cell to be barred, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds (the UE shall or may exclude the barred cell as a candidate for cell selection / reselection within up to 300 seconds). When the reception quality Squal and / or reception level Srxlev of another cell (the other cell uses the same frequency as the corresponding cell) derived according to Equation 1 is greater than 0 and / or satisfies the cell reselection criteria, the UE may select the other cell (if the selection criteria and / or cell reselection criteria are met, the UE may select another cell on the same frequency).

[0411] When the UE receives the MIB (upon receiving the MIB), the UE may determine whether the corresponding cell satisfies the first condition or the second condition based on the information included in the MIB (3c-50).

[0412] First condition: when a cellBarred field value included in the received MIB is set to 'barred' and / or PDCCH-ConfigSIB1 is not supported.

[0413] Second condition: a condition that does not correspond to the first condition

[0414] Seventh operation: When the first condition is met, in 3c-55, the UE may consider the corresponding cell as a prohibited cell, and may exclude the prohibited cell from the candidate cell list for cell selection / reselection within 300 seconds. When the value of the intraFreqReselection field included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells that use the same frequency as the prohibited cell within 300 seconds. When the value of the intraFreqReselection field included in the MIB is set to "allowed", when the (multiple) cells meet the cell reselection criteria, the UE may select the (multiple) cells, and the (multiple) cells use the same frequency as the prohibited cell.

[0415] Eighth operation: When the second condition is met, in 3c-60, the UE may consider the corresponding cell as an allowed cell, and may determine the corresponding cell as a candidate cell for cell selection / reselection. When the intraFreqReselection field value included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells that use the same frequency as the cell within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "allowed", when the (multiple) cells meet the cell reselection criteria, the UE may select the (multiple) cells, and the (multiple) cells use the same frequency as the cell.

[0416] When the selected candidate target cell broadcasts SIB1 in 3c-35, the UE may attempt to receive SIB1 in 3c-65.

[0417] When the UE cannot obtain SIB1, the UE may perform the seventh operation described in 3c-55 in 3c-70.

[0418] When the UE receives SIB1 (upon receiving SIB1), the UE may determine whether the corresponding cell satisfies the third condition or the fourth condition based on the information included in SIB1 (3c-75). The third condition and the fourth condition are as follows.

[0419] Third condition: When the UE identifies the FrequencyInfo UL-SIB included in the received SIB1 and does not support the bandwidth of all SCSs in the scs-SpecificCarrierList

[0420] Fourth condition: When the UE identifies the FrequencyInfo UL-SIB included in the received SIB1 and supports the bandwidth of at least one SCS in the scs-SpecificCarrierList (if the UE supports the bandwidth of at least one SCS in the scs-SpecificCarrierList in the FrequencyInfo UL-SIB in SIB1)

[0421] Ninth operation: When the third condition is met, in 3c-80, the UE may determine that the corresponding cell is inaccessible or may consider the corresponding cell to be a prohibited cell, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds. The UE may not select / reselect a cell(s) using the same frequency as the prohibited cell within 300 seconds.

[0422] Tenth operation: When the fourth condition is met, in 3c-85, the UE may determine that the corresponding cell is accessible. Then, the UE may derive the reception quality Squal and / or reception level Srxlev of the corresponding cell based on the information included in SIB1 by using equation 1, and when the reception quality Squal and / or reception level Srxlev satisfies the S criterion (Srxlev>0 and / or Squal>0), the UE may finally reselect the corresponding cell, otherwise, the UE may not finally reselect the corresponding cell.

[0423] Figure 3D A diagram for describing a cell reselection procedure in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown.

[0424] A UE in an RRC idle mode or an RRC inactive mode (operation 3d-01) may perform a series of operations while it resides in a serving cell (operation 3d-05).

[0425] In operation 3d-10, a UE in RRC idle mode or RRC inactive mode may receive system information broadcast by a BS of a serving cell. In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by a BS of a neighboring cell. System information may be divided into a master information block (MIB) and a system information block (SIB). In addition, SIB may be divided into SIB1 and SI messages (e.g., SIB2, SIB3, SIB4, SIB5, SIB6, SIB7, SIB8, or SIB9) that do not include SIB1. A UE in RRC idle mode or RRC inactive mode may pre-receive and read system information (e.g., MIB or SIB1) broadcast by a base station of a serving cell before the UE resides in a serving cell. For reference, MIB and SIB1 may be system information to be commonly applied to all UEs. SIB2 may be system information to be commonly applied by a UE in RRC idle mode or RRC inactive mode to the process of reselecting a same-frequency cell, a different-frequency cell, or a different RAT cell. SIB3, SIB4 and SIB5 may include information required for a UE in RRC idle mode or RRC inactive mode to reselect a cell.

[0426] SIB1 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a serving cell signal, and such information may be applied in a cell-specific manner. SIB2, SIB3, SIB4, and SIB5 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a neighboring cell signal. In detail, SIB2 may include common information for reselecting a same-frequency cell, a different-frequency cell, or a different-RAT cell, SIB3 may include information for reselecting only a same-frequency cell, SIB4 may include information for reselecting only a different-frequency cell, and SIB5 may include information for reselecting only a different-RAT cell.

[0427] In operation 3d-15, a UE in RRC idle mode or RRC inactive mode may wake up in a discontinuous reception (DRX) period and may measure a reference signal received power (RSRP) Qrxlevmeas and a reference signal received quality (RSRQ) Qqualmeas (operation 3d-15). The UE may calculate a reception level Srxlev and a reception quality Squal of a serving cell based on the measured values ​​by using parameters received from SIB1. The UE may compare the calculated value with a threshold value and may then determine whether to perform neighboring cell measurements for cell reselection. The reception level Srxlev and the reception quality Squal of a serving cell may be determined by using the above equation 1.

[0428] A UE in RRC idle mode or RRC inactive mode may not continuously perform neighbor cell measurements, but may determine whether to perform neighbor cell measurements based on measurement rules in order to minimize battery power consumption (operation 3d-20). In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by the BS of a neighboring cell, and may perform neighbor cell measurements by using system information broadcast by the serving cell where the UE is currently residing. When the reception level Srxlev and reception quality Squal of the serving cell measured in operation 3d-15 are lower than a threshold value (Srxlev≤SintraSearchP and Squal≤SIntraSearchQ), the UE in RRC idle mode or RRC inactive mode may measure the same frequency cell using the same frequency as the serving cell (operation 3d-20). That is, the reception quality Squal or reception level Srxlev of each same frequency cell using the same frequency as the serving cell may be derived based on SIB2 or / and SIB3 broadcast by the serving cell (application of equation 1).

[0429] For reference, information about the thresholds SIntraSearchP and SIntraSearchQ is included in SIB2. In addition, regardless of the quality of the serving cell, neighbor cell measurements can be performed on inter-frequency and inter-RAT cells having a higher priority than the frequency of the current serving cell (operation 3d-20). The UE can obtain information about priority from a dedicated RRC message (e.g., RRC Release message) or system information from the BS. The reception quality Squal or reception level Srxlev of each inter-frequency cell having a higher priority than the frequency of the serving cell can be derived based on SIB4 broadcast by the serving cell (according to Equation 1), and the reception quality Squal or reception level Srxlev of each inter-RAT cell having a higher priority than the frequency of the serving cell can be derived based on SIB5 broadcast by the serving cell (according to Equation 1). In addition, for an inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell, or for an inter-RAT cell having a priority lower than the frequency of the serving cell, when the reception level Srxlev and the reception quality Squal of the serving cell measured in operation 3d-15 are lower than the threshold value (Srxlex≤SnonIntraSearchP and Squal≤SintraSearchQ), the UE in RRC idle mode or RRC inactive mode can measure the neighboring inter-frequency cell using a frequency different from the serving cell, or measure the neighboring inter-RAT cell using a RAT different from the serving cell (3d-20). That is, the reception quality Squal or the reception level Srxlev of at least one inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell is derived based on SIB4 broadcast by the serving cell (according to Equation 1), and the reception quality Squal or the reception level Srxlev of at least one inter-RAT cell having a priority lower than the frequency of the serving cell is derived based on SIB5 broadcast by the serving cell (according to Equation 1). For reference, information about the thresholds SnonIntraSearchP and SnonIntraSearchQ is included in SIB2.

[0430] A UE in RRC idle mode or RRC inactive mode can perform a cell reselection evaluation process (3d-25) based on cell reselection priority and / or ranking, based on the measurement values ​​of neighboring cells (obtained in 3d-20). That is, when multiple cells that meet the cell reselection criteria have different priorities, the reselection of a frequency / RAT cell with a higher priority precedes the reselection of a frequency / RAT cell with a lower priority (if multiple cells of different priorities meet the cell reselection criteria, the cell reselection for a higher priority RAT / frequency should precede the RAT / frequency with a lower priority). Priority information is included in the system information (SIB2, SIB4 and SIB5) broadcast by the serving cell, or is included in the RRCRelease message received when the UE transitions from RRC connected mode to RRC idle mode or RRC inactive mode. The information about priority included in the RRCRelease message may have priority over the information about priority included in the system information broadcast by the serving cell. The operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a higher priority than the frequency of the serving cell will now be described below.

[0431] -First operation:

[0432] *When SIB2 including the threshold threshServingLowQ is broadcast and 1 second has passed after the UE resides in the current serving cell, when the reception quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighQ during a specific time interval TreselectionRAT (Squal>ThreshX during the time interval TreselectionRAT), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0433] - Second operation:

[0434] *When the UE cannot perform the first operation, the UE may perform the second operation.

[0435] *When 1 second has passed after the UE camps on the current serving cell and the reception level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighP during a specific time interval TreselectionRAT (During the time interval TreselectionRAT, Srxlev>ThreshX,HighP), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0436] In this regard, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-frequency cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB4 broadcast by the serving cell). In addition, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-RAT cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB5 broadcast by the serving cell).

[0437] Furthermore, the operation of a ranking-based cell reselection evaluation procedure of the UE for an intra-frequency cell belonging to the frequency of the current serving cell or an inter-frequency cell having a priority equal to the frequency of the current serving cell will now be described below.

[0438] -Third operation:

[0439] *When the reception quality Squal and reception level Srxlev of each intra-frequency / inter-frequency cell are greater than 0, the UE can derive the ranking of each cell based on the measurement value of RSRP (the UE should perform ranking on all cells that meet the cell selection criterion S). The ranking of the serving cell and the neighboring cell can be calculated separately by using the above equation 2.

[0440] In the aforementioned equation 2, Qmeas,s indicates the RSRP measurement value of the serving cell, Qmeas,n indicates the RSRP measurement value of the neighboring cell, Qhyst indicates the hysteresis value of the serving cell, and Qoffset indicates the offset between the serving cell and the neighboring cell. SIB2 includes the Qhyst value, and the Qhyst value can be used together to reselect the same-frequency / different-frequency cells. When reselecting the same-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB3. When reselecting the different-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB4. When the ranking of the neighboring cell derived according to equation 2 is greater than the ranking of the serving cell (i.e., Rn>Rs), the UE can reside in the best cell among the neighboring cells.

[0441] Furthermore, the operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a lower priority than the frequency of the current serving cell will now be described below.

[0442] *439-Fourth Operation:

[0443] *When broadcasting SIB2 including the threshold threshServingLowQ and 1 second has elapsed after the UE camps on the current serving cell, when the received quality Squal of the current serving cell is less than the threshold ThreshServing,LowQ (Squal < ThreshServing,LowQ), and the received quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Squal > ThreshX,LowQ), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0444] - Fifth operation:

[0445] *When the UE cannot perform the fourth operation, the UE may perform the fifth operation.

[0446] *When 1 second has elapsed after the UE camps on the current serving cell, the received level Srxlev of the current serving cell is lower than the threshold ThreshServing,LowP (Srxlev < ThreshServing,LowP), and the received level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Srxlev > ThreshX,LowP), then the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0447] In this regard, the fourth or fifth operation of the UE for the inter-frequency cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-frequency cell and the thresholds ThrehX,LowQ and ThreshX,LowP included in SIB4 broadcast by the serving cell. The fourth or fifth operation of the UE for the inter-RAT cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-RAT cell and the thresholds ThreshX,LowQ and ThreshX,LowP included in SIB5 broadcast by the serving cell. For example, SIB4 includes the Qqualmin value or Qrxlevmin value, and the received quality Squal or received level Srxlev of the inter-frequency cell may be derived based on this value.

[0448] In 3d-30, the UE may derive a candidate cell list, and then may select a candidate target cell based on a priority and / or ranking from the candidate cell list. When selecting a candidate target cell, in 3d-35, the UE in RRC idle mode or RRC inactive mode may determine whether to select the corresponding cell by attempting to receive the MIB and SIB1 broadcast by the corresponding cell before the UE finally selects the corresponding cell. At this time, the UE performs the following operations.

[0449] When the selected candidate target cell broadcasts the MIB in 3d-35, the UE may attempt to receive the MIB in 3d-40.

[0450] When the UE cannot obtain the MIB, the UE can perform the sixth operation in 3d-45.

[0451] Sixth operation: The UE may consider the cell state of the corresponding cell to be barred, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds (the UE shall or may exclude the barred cell as a candidate for cell selection / reselection within up to 300 seconds). When the reception quality Squal and / or reception level Srxlev of another cell (the other cell uses the same frequency as the corresponding cell) derived according to Equation 1 is greater than 0 and / or satisfies the cell reselection criteria, the UE may select the other cell (if the selection criteria and / or cell reselection criteria are met, the UE may select another cell on the same frequency).

[0452] When the UE receives the MIB (upon receiving the MIB), the UE may determine whether the corresponding cell satisfies the first condition or the second condition based on the information included in the MIB (3d-50).

[0453] First condition: when a cellBarred field value included in the received MIB is set to 'barred' and / or PDCCH-ConfigSIB1 is not supported.

[0454] Second condition: a condition that does not correspond to the first condition

[0455] Seventh operation: When the first condition is met, in 3d-55, the UE may consider the corresponding cell as a prohibited cell, and may exclude the prohibited cell from the candidate cell list for cell selection / reselection within 300 seconds. When the value of the intraFreqReselection field included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells that use the same frequency as the prohibited cell within 300 seconds. When the value of the intraFreqReselection field included in the MIB is set to "allowed", when the (multiple) cells meet the cell reselection criteria, the UE may select the (multiple) cells, and the (multiple) cells use the same frequency as the prohibited cell.

[0456] Eighth operation: When the second condition is met, in 3d-60, the UE may consider the corresponding cell as an allowed cell, and may determine the corresponding cell as a candidate cell for cell selection / reselection. When the intraFreqReselection field value included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells that use the same frequency as the cell within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "allowed", when the (multiple) cells meet the cell reselection criteria, the UE may select the (multiple) cells, and the (multiple) cells use the same frequency as the cell.

[0457] When the selected candidate target cell broadcasts SIB1 in 3d-35, the UE may attempt to receive SIB1 in 3d-65.

[0458] When the UE cannot obtain SIB1, the UE can perform the seventh operation described in 3d-55 in 3d-70.

[0459] When the UE receives SIB1 (upon receiving SIB1), the UE may determine whether the corresponding cell satisfies the third condition or the fourth condition based on the information included in SIB1 (3d-75). The third condition and the fourth condition are as follows.

[0460] Third condition: When the UE identifies all FrequencyInfoUL-SIBs and FrequencyInfoDL-SIBs included in the received SIB1 and does not support the bandwidth of all SCSs in scs-SpecificCarrierList

[0461] Fourth condition: When the UE identifies the FrequencyInfoUL-SIB and FrequencyInfoDL-SIB included in the received SIB1 and supports the bandwidth of at least one SCS in the scs-SpecificCarrierList (if the UE supports the bandwidth of at least one SCS in the scs-SpecificCarrierList in the FrequencyInfoUL-SIB in SIB1 and the bandwidth of at least one SCS in the scs-SpecificCarrierList in the FrequencyInfoDL-SIB in SIB1)

[0462] Ninth operation: When the third condition is met, in 3d-80, the UE may determine that the corresponding cell is inaccessible or may consider the corresponding cell to be a prohibited cell, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds. The UE may not select / reselect (multiple) cells using the same frequency as the prohibited cell within 300 seconds.

[0463] Tenth operation: When the fourth condition is met, in 3d-85, the UE may determine that the corresponding cell is accessible. Then, the UE may derive the reception quality Squal and / or the reception level Srxlev of the corresponding cell based on the information included in SIB1 by using equation 1, and when the reception quality Squal and / or the reception level Srxlev satisfies the S criterion (Srxlev>0 and / or Squal>0), the UE may eventually reselect the corresponding cell, otherwise, the UE may not eventually reselect the corresponding cell.

[0464] Figure 3E A diagram for describing a cell reselection procedure in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown.

[0465] The UE in the RRC idle mode or the RRC inactive mode (operation 3e-01) may perform a series of operations while it camps on a serving cell (operation 3e-05).

[0466] In operation 3e-10, a UE in RRC idle mode or RRC inactive mode may receive system information broadcast by a BS of a serving cell. In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by a BS of a neighboring cell. System information may be divided into a master information block (MIB) and a system information block (SIB). In addition, SIB may be divided into SIB1 and SI messages (e.g., SIB2, SIB3, SIB4, SIB5, SIB6, SIB7, SIB8, or SIB9) that do not include SIB1. A UE in RRC idle mode or RRC inactive mode may pre-receive and read system information (e.g., MIB or SIB1) broadcast by a base station of a serving cell before the UE resides in a serving cell. For reference, MIB and SIB1 may be system information to be commonly applied to all UEs. SIB2 may be system information to be commonly applied by UEs in RRC idle mode or RRC inactive mode to the process of reselecting a same-frequency cell, a different-frequency cell, or a different RAT cell. SIB3, SIB4 and SIB5 may include information required for a UE in RRC idle mode or RRC inactive mode to reselect a cell.

[0467] SIB1 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a serving cell signal, and such information may be applied in a cell-specific manner. SIB2, SIB3, SIB4, and SIB5 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a neighboring cell signal. In detail, SIB2 may include common information for reselecting a same-frequency cell, a different-frequency cell, or a different-RAT cell, SIB3 may include information for reselecting only a same-frequency cell, SIB4 may include information for reselecting only a different-frequency cell, and SIB5 may include information for reselecting only a different-RAT cell.

[0468] In operation 3e-15, a UE in RRC idle mode or RRC inactive mode may wake up in a discontinuous reception (DRX) period and may measure a reference signal received power (RSRP) Qrxlevmeas and a reference signal received quality (RSRQ) Qqualmeas (operation 3e-15). The UE may calculate a reception level Srxlev and a reception quality Squal of a serving cell based on the measured values ​​by using parameters received from SIB1. The UE may compare the calculated value with a threshold value and may then determine whether to perform neighboring cell measurement for cell reselection. The reception level Srxlev and the reception quality Squal of a serving cell may be determined by using the above equation 1.

[0469] A UE in RRC idle mode or RRC inactive mode may not continuously perform neighbor cell measurements, but may determine whether to perform neighbor cell measurements based on measurement rules in order to minimize battery power consumption (operation 3e-20). In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by the BS of a neighbor cell, and may perform neighbor cell measurements by using system information broadcast by a serving cell where the UE is currently residing. When the reception level Srxlev and reception quality Squal of the serving cell measured in operation 3e-15 are lower than a threshold value (Srxlev≤SintraSearchP and Squal≤SIntraSearchQ), the UE in RRC idle mode or RRC inactive mode may measure the same frequency cell using the same frequency as the serving cell (operation 3e-20). That is, the reception quality Squal or reception level Srxlev of each same frequency cell using the same frequency as the serving cell may be derived based on SIB2 or / and SIB3 broadcast by the serving cell (application of equation 1).

[0470] For reference, information about the thresholds SIntraSearchP and SIntraSearchQ is included in SIB2. In addition, regardless of the quality of the serving cell, neighbor cell measurements can be performed on inter-frequency and inter-RAT cells having a higher priority than the frequency of the current serving cell (operation 3e-20). The UE can obtain information about priority from a dedicated RRC message (e.g., RRC Release message) or system information from the BS. The reception quality Squal or reception level Srxlev of each inter-frequency cell having a higher priority than the frequency of the serving cell can be derived based on SIB4 broadcast by the serving cell (according to Equation 1), and the reception quality Squal or reception level Srxlev of each inter-RAT cell having a higher priority than the frequency of the serving cell can be derived based on SIB5 broadcast by the serving cell (according to Equation 1). In addition, for an inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell, or for an inter-RAT cell having a frequency lower than the frequency of the serving cell, when the reception level Srxlev and the reception quality Squal of the serving cell measured in operation 3e-15 are lower than the threshold value (Srxlex≤SnonIntraSearchP and Squal≤SintraSearchQ), the UE in the RRC idle mode or the RRC inactive mode can measure the neighboring inter-frequency cell using a frequency different from the serving cell, or measure the neighboring inter-RAT cell using a RAT different from the serving cell (3e-20). That is, the reception quality Squal or the reception level Srxlev of at least one inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell is derived based on SIB4 broadcasted by the serving cell (according to Equation 1), and the reception quality Squal or the reception level Srxlev of at least one inter-RAT cell having a frequency lower than the frequency of the serving cell is derived based on SIB5 broadcasted by the serving cell (according to Equation 1). For reference, information about the thresholds SnonIntraSearchP and SnonIntraSearchQ is included in SIB2.

[0471] A UE in RRC idle mode or RRC inactive mode may perform a cell reselection evaluation process (3e-25) based on cell reselection priority and / or ranking, based on the measurement values ​​of neighboring cells (obtained in 3e-20). That is, when multiple cells that meet the cell reselection criteria have different priorities, the reselection of a frequency / RAT cell with a higher priority precedes the reselection of a frequency / RAT cell with a lower priority (if multiple cells of different priorities meet the cell reselection criteria, the cell reselection for a higher priority RAT / frequency should precede the RAT / frequency with a lower priority). Priority information is included in the system information (SIB2, SIB4, and SIB5) broadcast by the serving cell, or is included in the RRCRelease message received when the UE transitions from RRC connected mode to RRC idle mode or RRC inactive mode. The information about priority included in the RRCRelease message may have priority over the information about priority included in the system information broadcast by the serving cell. The operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a higher priority than the frequency of the serving cell will now be described below.

[0472] -First operation:

[0473] *When SIB2 including the threshold threshServingLowQ is broadcast and 1 second has passed after the UE resides in the current serving cell, when the reception quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighQ during a specific time interval TreselectionRAT (Squal>ThreshX during the time interval TreselectionRAT), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0474] - Second operation:

[0475] *When the UE cannot perform the first operation, the UE may perform the second operation.

[0476] *When 1 second has passed after the UE camps on the current serving cell and the reception level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighP during a specific time interval TreselectionRAT (During the time interval TreselectionRAT, Srxlev>ThreshX,HighP), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0477] In this regard, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-frequency cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB4 broadcast by the serving cell). In addition, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-RAT cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB5 broadcast by the serving cell).

[0478] Furthermore, the operation of a ranking-based cell reselection evaluation procedure of the UE for an intra-frequency cell belonging to the frequency of the current serving cell or an inter-frequency cell having a priority equal to the frequency of the current serving cell will now be described below.

[0479] -Third operation:

[0480] *When the reception quality Squal and reception level Srxlev of each intra-frequency / inter-frequency cell are greater than 0, the UE can derive the ranking of each cell based on the measurement value of RSRP (the UE should perform ranking on all cells that meet the cell selection criterion S). The ranking of the serving cell and the neighboring cell can be calculated separately by using the above equation 2.

[0481] In the aforementioned equation 2, Qmeas,s indicates the RSRP measurement value of the serving cell, Qmeas,n indicates the RSRP measurement value of the neighboring cell, Qhyst indicates the hysteresis value of the serving cell, and Qoffset indicates the offset between the serving cell and the neighboring cell. SIB2 includes the Qhyst value, and the Qhyst value can be used together to reselect the same-frequency / different-frequency cells. When reselecting the same-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB3. When reselecting the different-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB4. When the ranking of the neighboring cell derived according to equation 2 is greater than the ranking of the serving cell (i.e., Rn>Rs), the UE can reside in the best cell among the neighboring cells.

[0482] Furthermore, the operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a lower priority than the frequency of the current serving cell will now be described below.

[0483] *480-Fourth Operation:

[0484] *When broadcasting SIB2 including the threshold threshServingLowQ and 1 second has passed after the UE camps on the current serving cell, when the received quality Squal of the current serving cell is less than the threshold ThreshServing,LowQ (Squal < ThreshServing,LowQ), and the received quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Squal > ThreshX,LowQ), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0485] - Fifth operation:

[0486] *When the UE cannot perform the fourth operation, the UE may perform the fifth operation.

[0487] *When 1 second has passed after the UE camps on the current serving cell, the received level Srxlev of the current serving cell is lower than the threshold ThreshServing,LowP (Srxlev < ThreshServing,LowP), and the received level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Srxlev > ThreshX,LowP), then the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0488] In this regard, the fourth or fifth operation of the UE for the inter-frequency cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-frequency cell and the thresholds ThrehX,LowQ and ThreshX,LowP included in SIB4 broadcast by the serving cell. The fourth or fifth operation of the UE for the inter-RAT cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-RAT cell and the thresholds ThreshX,LowQ and ThreshX,LowP included in SIB5 broadcast by the serving cell. For example, SIB4 includes the Qqualmin value or Qrxlevmin value, and the received quality Squal or received level Srxlev of the inter-frequency cell may be derived based on this value.

[0489] In 3e-30, the UE may derive a candidate cell list, and then may select a candidate target cell based on a priority and / or ranking from the candidate cell list. When selecting a candidate target cell, in 3e-35, the UE in RRC idle mode or RRC inactive mode may determine whether to select the corresponding cell by attempting to receive the MIB and SIB1 broadcast by the corresponding cell before the UE finally selects the corresponding cell. At this time, the UE performs the following operations.

[0490] When the selected candidate target cell broadcasts the MIB in 3e-35, the UE may attempt to receive the MIB in 3e-40.

[0491] When the UE cannot obtain the MIB, the UE may perform the sixth operation in 3e-45.

[0492] Sixth operation: The UE may consider the cell state of the corresponding cell to be barred, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds (the UE shall or may exclude the barred cell as a candidate for cell selection / reselection within up to 300 seconds). When the reception quality Squal and / or reception level Srxlev of another cell (the other cell uses the same frequency as the corresponding cell) derived according to Equation 1 is greater than 0 and / or satisfies the cell reselection criteria, the UE may select the other cell (if the selection criteria and / or cell reselection criteria are met, the UE may select another cell on the same frequency).

[0493] When the UE receives the MIB (upon receiving the MIB), the UE may determine whether the corresponding cell satisfies the first condition or the second condition based on information included in the MIB (3e-50).

[0494] First condition: when a cellBarred field value included in the received MIB is set to 'barred' and / or PDCCH-ConfigSIB1 is not supported.

[0495] Second condition: a condition that does not correspond to the first condition

[0496] Seventh operation: When the first condition is met, in 3e-55, the UE may consider the corresponding cell as a prohibited cell, and may exclude the prohibited cell from the candidate cell list for cell selection / reselection within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells using the same frequency as the prohibited cell within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "allowed", when the (multiple) cell meets the cell reselection criteria, the UE may select the (multiple) cell, and the (multiple) cell uses the same frequency as the prohibited cell.

[0497] Eighth operation: When the second condition is met, in 3e-60, the UE may consider the corresponding cell as an allowed cell, and may determine the corresponding cell as a candidate cell for cell selection / reselection. When the intraFreqReselection field value included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells using the same frequency as the cell within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "allowed", when the (multiple) cell meets the cell reselection criteria, the UE may select the (multiple) cell, and the (multiple) cell uses the same frequency as the cell.

[0498] When the selected candidate target cell broadcasts SIB1 in 3e-35, the UE may attempt to receive SIB1 in 3e-65.

[0499] When the UE cannot obtain SIB1, the UE may perform the seventh operation described in 3e-55 in 3e-70.

[0500] When the UE receives SIB1 (upon receiving SIB1), the UE may determine whether the corresponding cell satisfies the third condition or the fourth condition (3e-75) based on information included in the MIB and SIB1. The third condition and the fourth condition are as follows.

[0501] Third condition: When the UE identifies the SCS value configured in subCarrierSpacingCommon of the received MIB and does not support the bandwidth of the initial DLBWP using the SCS value configured in locationAndBandwidth in the received SIB1

[0502] Fourth condition: When the UE identifies the SCS value configured in subCarrierSpacingCommon of the received MIB and supports the bandwidth of the initial DLBWP using the SCS value in the configured locationAndBandwidth in the received SIB1 (if the UE supports the bandwidth of the initial DLBWP in locationAndBandwidth in SIB1)

[0503] Ninth operation: When the third condition is met, in 3e-80, the UE may determine that the corresponding cell is inaccessible or may consider the corresponding cell to be a prohibited cell, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds. The UE may not select / reselect a cell (or cells) using the same frequency as the prohibited cell within 300 seconds.

[0504] Tenth operation: When the fourth condition is met, in 3e-85, the UE may determine that the corresponding cell is accessible. Then, the UE may derive the reception quality Squal and / or the reception level Srxlev of the corresponding cell based on the information included in SIB1 by using equation 1, and when the reception quality Squal and / or the reception level Srxlev satisfies the S criterion (Srxlev>0 and / or Squal>0), the UE may finally reselect the corresponding cell, otherwise, the UE may not finally reselect the corresponding cell.

[0505] Figure 3F A diagram for describing a cell reselection procedure in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown.

[0506] A UE in RRC idle mode or RRC inactive mode (operation 3f-01) may perform a series of operations while it resides in a serving cell (operation 3f-05).

[0507] In operation 3f-10, a UE in RRC idle mode or RRC inactive mode may receive system information broadcast by a BS of a serving cell. In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by a BS of a neighboring cell. System information may be divided into a master information block (MIB) and a system information block (SIB). In addition, SIB may be divided into SIB1 and SI messages (e.g., SIB2, SIB3, SIB4, SIB5, SIB6, SIB7, SIB8, or SIB9) that do not include SIB1. A UE in RRC idle mode or RRC inactive mode may pre-receive and read system information (e.g., MIB or SIB1) broadcast by a base station of a serving cell before the UE resides in a serving cell. For reference, MIB and SIB1 may be system information to be commonly applied to all UEs. SIB2 may be system information to be commonly applied by UEs in RRC idle mode or RRC inactive mode to the process of reselecting a same-frequency cell, a different-frequency cell, or a different RAT cell. SIB3, SIB4 and SIB5 may include information required for a UE in RRC idle mode or RRC inactive mode to reselect a cell.

[0508] SIB1 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a serving cell signal, and such information may be applied in a cell-specific manner. SIB2, SIB3, SIB4, and SIB5 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a neighboring cell signal. In detail, SIB2 may include common information for reselecting a same-frequency cell, a different-frequency cell, or a different-RAT cell, SIB3 may include information for reselecting only a same-frequency cell, SIB4 may include information for reselecting only a different-frequency cell, and SIB5 may include information for reselecting only a different-RAT cell.

[0509] In operation 3f-15, a UE in RRC idle mode or RRC inactive mode may wake up in a discontinuous reception (DRX) period and may measure a reference signal received power (RSRP) Qrxlevmeas and a reference signal received quality (RSRQ) Qqualmeas (operation 3f-15). The UE may calculate a reception level Srxlev and a reception quality Squal of a serving cell based on the measured values ​​by using parameters received from SIB1. The UE may compare the calculated value with a threshold value and may then determine whether to perform neighboring cell measurements for cell reselection. The reception level Srxlev and the reception quality Squal of a serving cell may be determined by using the above equation 1.

[0510] A UE in RRC idle mode or RRC inactive mode may not continuously perform neighbor cell measurements, but may determine whether to perform neighbor cell measurements based on measurement rules in order to minimize battery power consumption (operation 3f-20). In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by the BS of a neighboring cell, and may perform neighbor cell measurements by using system information broadcast by the serving cell where the UE is currently residing. When the reception level Srxlev and reception quality Squal of the serving cell measured in operation 3f-15 are lower than a threshold value (Srxlev≤SintraSearchP and Squal≤SIntraSearchQ), the UE in RRC idle mode or RRC inactive mode may measure the same frequency cell using the same frequency as the serving cell (operation 3f-20). That is, the reception quality Squal or reception level Srxlev of each same frequency cell using the same frequency as the serving cell may be derived based on SIB2 or / and SIB3 broadcast by the serving cell (application of equation 1).

[0511] For reference, information about the thresholds SIntraSearchP and SIntraSearchQ is included in SIB2. In addition, regardless of the quality of the serving cell, neighbor cell measurements can be performed on inter-frequency and inter-RAT cells having a higher priority than the frequency of the current serving cell (operation 3f-20). The UE can obtain information about priority from a dedicated RRC message (e.g., RRC Release message) or system information from the BS. The reception quality Squal or reception level Srxlev of each inter-frequency cell having a higher priority than the frequency of the serving cell can be derived based on SIB4 broadcast by the serving cell (according to Equation 1), and the reception quality Squal or reception level Srxlev of each inter-RAT cell having a higher priority than the frequency of the serving cell can be derived based on SIB5 broadcast by the serving cell (according to Equation 1). In addition, for an inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell, or for an inter-RAT cell having a frequency lower than the frequency of the serving cell, when the reception level Srxlev and the reception quality Squal of the serving cell measured in operation 3f-15 are lower than the threshold value (Srxlex≤SnonIntraSearchP and Squal≤SintraSearchQ), the UE in RRC idle mode or RRC inactive mode can measure the neighboring inter-frequency cell using a frequency different from the serving cell, or measure the neighboring inter-RAT cell using a RAT different from the serving cell (3f-20). That is, the reception quality Squal or the reception level Srxlev of at least one inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell is derived based on SIB4 broadcasted by the serving cell (according to Equation 1), and the reception quality Squal or the reception level Srxlev of at least one inter-RAT cell having a frequency lower than the frequency of the serving cell is derived based on SIB5 broadcasted by the serving cell (according to Equation 1). For reference, information about the thresholds SnonIntraSearchP and SnonIntraSearchQ is included in SIB2.

[0512] A UE in RRC idle mode or RRC inactive mode may perform a cell reselection evaluation process (3f-25) based on cell reselection priority and / or ranking, based on the measurement values ​​of neighboring cells (obtained in 3f-20). That is, when multiple cells that meet the cell reselection criteria have different priorities, the reselection of a frequency / RAT cell with a higher priority precedes the reselection of a frequency / RAT cell with a lower priority (if multiple cells of different priorities meet the cell reselection criteria, the cell reselection for a higher priority RAT / frequency should precede the RAT / frequency with a lower priority). Priority information is included in the system information (SIB2, SIB4, and SIB5) broadcast by the serving cell, or is included in the RRCRelease message received when the UE transitions from RRC connected mode to RRC idle mode or RRC inactive mode. The information about priority included in the RRCRelease message may have priority over the information about priority included in the system information broadcast by the serving cell. The operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a higher priority than the frequency of the serving cell will now be described below.

[0513] -First operation:

[0514] *When SIB2 including the threshold threshServingLowQ is broadcast and 1 second has passed after the UE resides in the current serving cell, when the reception quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighQ during a specific time interval TreselectionRAT (Squal>ThreshX during the time interval TreselectionRAT), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0515] - Second operation:

[0516] *When the UE cannot perform the first operation, the UE may perform the second operation.

[0517] *When 1 second has passed after the UE camps on the current serving cell and the reception level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighP during a specific time interval TreselectionRAT (During the time interval TreselectionRAT, Srxlev>ThreshX,HighP), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0518] In this regard, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-frequency cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB4 broadcast by the serving cell). In addition, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-RAT cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB5 broadcast by the serving cell).

[0519] Furthermore, the operation of a ranking-based cell reselection evaluation procedure of the UE for an intra-frequency cell belonging to the frequency of the current serving cell or an inter-frequency cell having a priority equal to the frequency of the current serving cell will now be described below.

[0520] -Third operation:

[0521] *When the reception quality Squal and reception level Srxlev of each intra-frequency / inter-frequency cell are greater than 0, the UE can derive the ranking of each cell based on the measurement value of RSRP (the UE should perform ranking on all cells that meet the cell selection criterion S). The ranking of the serving cell and the neighboring cell can be calculated separately by using the above equation 2.

[0522] In the aforementioned equation 2, Qmeas,s indicates the RSRP measurement value of the serving cell, Qmeas,n indicates the RSRP measurement value of the neighboring cell, Qhyst indicates the hysteresis value of the serving cell, and Qoffset indicates the offset between the serving cell and the neighboring cell. SIB2 includes the Qhyst value, and the Qhyst value can be used together to reselect the same-frequency / different-frequency cells. When reselecting the same-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB3. When reselecting the different-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB4. When the ranking of the neighboring cell derived according to equation 2 is greater than the ranking of the serving cell (i.e., Rn>Rs), the UE can reside in the best cell among the neighboring cells.

[0523] Furthermore, the operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a lower priority than the frequency of the current serving cell will now be described below.

[0524] *521-Fourth Operation:

[0525] *When broadcasting SIB2 including the threshold threshServingLowQ and 1 second has passed after the UE camps on the current serving cell, when the received quality Squal of the current serving cell is less than the threshold ThreshServing,LowQ (Squal < ThreshServing,LowQ), and the received quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Squal > ThreshX,LowQ), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0526] - Fifth operation:

[0527] *When the UE cannot perform the fourth operation, the UE may perform the fifth operation.

[0528] *When 1 second has passed after the UE camps on the current serving cell, the received level Srxlev of the current serving cell is lower than the threshold ThreshServing,LowP (Srxlev < ThreshServing,LowP), and the received level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Srxlev > ThreshX,LowP), then the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0529] In this regard, the fourth or fifth operation of the UE for the inter-frequency cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-frequency cell and the thresholds ThrehX,LowQ and ThreshX,LowP included in SIB4 broadcast by the serving cell. The fourth or fifth operation of the UE for the inter-RAT cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-RAT cell and the thresholds ThreshX,LowQ and ThreshX,LowP included in SIB5 broadcast by the serving cell. For example, SIB4 includes the Qqualmin value or Qrxlevmin value, and the received quality Squal or received level Srxlev of the inter-frequency cell may be derived based on this value.

[0530] In 3f-30, the UE may derive a candidate cell list, and then may select a candidate target cell based on a priority and / or ranking from the candidate cell list. When selecting a candidate target cell, in 3f-35, the UE in RRC idle mode or RRC inactive mode may determine whether to select the corresponding cell by attempting to receive the MIB and SIB1 broadcast by the corresponding cell before the UE finally selects the corresponding cell. At this time, the UE performs the following operations.

[0531] When the selected candidate target cell broadcasts the MIB in 3f-35, the UE may attempt to receive the MIB in 3f-40.

[0532] When the UE cannot obtain the MIB, the UE may perform the sixth operation in 3f-45.

[0533] Sixth operation: The UE may consider the cell state of the corresponding cell to be barred, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds (the UE shall or may exclude the barred cell as a candidate for cell selection / reselection within up to 300 seconds). When the reception quality Squal and / or reception level Srxlev of another cell (the other cell uses the same frequency as the corresponding cell) derived according to Equation 1 is greater than 0 and / or satisfies the cell reselection criteria, the UE may select the other cell (if the selection criteria and / or cell reselection criteria are met, the UE may select another cell on the same frequency).

[0534] When the UE receives the MIB (upon receiving the MIB), the UE may determine whether the corresponding cell satisfies the first condition or the second condition based on the information included in the MIB (3f-50).

[0535] First condition: when a cellBarred field value included in the received MIB is set to 'barred' and / or PDCCH-ConfigSIB1 is not supported.

[0536] Second condition: a condition that does not correspond to the first condition

[0537] Seventh operation: When the first condition is met, in 3f-55, the UE may consider the corresponding cell as a prohibited cell, and may exclude the prohibited cell from the candidate cell list for cell selection / reselection within 300 seconds. When the value of the intraFreqReselection field included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells that use the same frequency as the prohibited cell within 300 seconds. When the value of the intraFreqReselection field included in the MIB is set to "allowed", when the (multiple) cells meet the cell reselection criteria, the UE may select the (multiple) cells, and the (multiple) cells use the same frequency as the prohibited cell.

[0538] Eighth operation: When the second condition is met, in 3f-60, the UE may consider the corresponding cell as an allowed cell, and may determine the corresponding cell as a candidate cell for cell selection / reselection. When the intraFreqReselection field value included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells that use the same frequency as the cell within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "allowed", when the (multiple) cells meet the cell reselection criteria, the UE may select the (multiple) cells, and the (multiple) cells use the same frequency as the cell.

[0539] When the selected candidate target cell broadcasts SIB1 in 3f-35, the UE may attempt to receive SIB1 in 3f-65.

[0540] When the UE cannot obtain SIB1, the UE may perform the seventh operation described in 3f-55 ​​in 3f-70.

[0541] When the UE receives SIB1 (upon receiving SIB1), the UE can determine whether the corresponding cell satisfies the third condition or the fourth condition (3f-75) based on the information included in the MIB and SIB1. The third condition and the fourth condition are as follows.

[0542] Third condition: When the UE identifies the SCS value configured in subCarrierSpacingCommon of the received MIB and does not support the bandwidth of the initial ULBWP using the SCS value configured in locationAndBandwidth in the received SIB1

[0543] Fourth condition: When the UE identifies the SCS value configured in subCarrierSpacingCommon of the received MIB and supports the bandwidth of the initial UL BWP using the SCS value in the configured locationAndBandwidth in the received SIB1 (if the UE supports the bandwidth of the initial UL BWP in locationAndBandwidth in SIB1)

[0544] Ninth operation: When the third condition is met, in 3f-80, the UE may determine that the corresponding cell is inaccessible or may consider the corresponding cell to be a prohibited cell, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds. The UE may not select / reselect (multiple) cells using the same frequency as the prohibited cell within 300 seconds.

[0545] Tenth operation: When the fourth condition is met, in 3f-85, the UE may determine that the corresponding cell is accessible. Then, the UE may derive the reception quality Squal and / or the reception level Srxlev of the corresponding cell based on the information included in SIB1 by using equation 1, and when the reception quality Squal and / or the reception level Srxlev satisfies the S criterion (Srxlev>0 and / or Squal>0), the UE may finally reselect the corresponding cell, otherwise, the UE may not finally reselect the corresponding cell.

[0546] Figure 3G A diagram for describing a cell reselection procedure in an RRC idle mode or an RRC inactive mode of a UE based on system information broadcast by a BS according to another embodiment of the present disclosure is shown.

[0547] A UE in RRC idle mode or RRC inactive mode (operation 3g-01) may perform a series of operations while it resides in a serving cell (operation 3g-05).

[0548] In operation 3g-10, a UE in RRC idle mode or RRC inactive mode may receive system information broadcast by a BS of a serving cell. In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by a BS of a neighboring cell. System information may be divided into a master information block (MIB) and a system information block (SIB). In addition, SIB may be divided into SIB1 and SI messages (e.g., SIB2, SIB3, SIB4, SIB5, SIB6, SIB7, SIB8, or SIB9) that do not include SIB1. A UE in RRC idle mode or RRC inactive mode may pre-receive and read system information (e.g., MIB or SIB1) broadcast by a base station of a serving cell before the UE resides in a serving cell. For reference, MIB and SIB1 may be system information to be commonly applied to all UEs. SIB2 may be system information to be commonly applied by UEs in RRC idle mode or RRC inactive mode to the process of reselecting a same-frequency cell, a different-frequency cell, or a different RAT cell. SIB3, SIB4 and SIB5 may include information required for a UE in RRC idle mode or RRC inactive mode to reselect a cell.

[0549] SIB1 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a serving cell signal, and such information may be applied in a cell-specific manner. SIB2, SIB3, SIB4, and SIB5 may include information about parameters, such as a minimum required reception level, a minimum required quality level, or a threshold for determining whether to measure a neighboring cell signal. In detail, SIB2 may include common information for reselecting a same-frequency cell, a different-frequency cell, or a different-RAT cell, SIB3 may include information for reselecting only a same-frequency cell, SIB4 may include information for reselecting only a different-frequency cell, and SIB5 may include information for reselecting only a different-RAT cell.

[0550] In operation 3g-15, a UE in RRC idle mode or RRC inactive mode may wake up in a discontinuous reception (DRX) period and may measure a reference signal received power (RSRP) Qrxlevmeas and a reference signal received quality (RSRQ) Qqualmeas (operation 3g-15). The UE may calculate a reception level Srxlev and a reception quality Squal of a serving cell based on the measured values ​​by using parameters received from SIB1. The UE may compare the calculated value with a threshold value and may then determine whether to perform neighboring cell measurements for cell reselection. The reception level Srxlev and the reception quality Squal of a serving cell may be determined by using the above equation 1.

[0551] A UE in RRC idle mode or RRC inactive mode may not continuously perform neighbor cell measurements, but may determine whether to perform neighbor cell measurements based on measurement rules in order to minimize battery power consumption (operation 3g-20). In this regard, a UE in RRC idle mode or RRC inactive mode may not receive system information broadcast by the BS of a neighboring cell, and may perform neighbor cell measurements by using system information broadcast by a serving cell where the UE is currently residing. When the reception level Srxlev and reception quality Squal of the serving cell measured in operation 3g-15 are lower than a threshold value (Srxlev≤SintraSearchP and Squal≤SIntraSearchQ), the UE in RRC idle mode or RRC inactive mode may measure the same frequency cell using the same frequency as the serving cell (operation 3g-20). That is, the reception quality Squal or reception level Srxlev of each same frequency cell using the same frequency as the serving cell may be derived based on SIB2 or / and SIB3 broadcast by the serving cell (application of equation 1).

[0552] For reference, information about the thresholds SIntraSearchP and SIntraSearchQ is included in SIB2. In addition, regardless of the quality of the serving cell, neighbor cell measurements can be performed on inter-frequency and inter-RAT cells having a higher priority than the frequency of the current serving cell (operation 3g-20). The UE can obtain information about priority from a dedicated RRC message (e.g., RRC Release message) or system information from the BS. The reception quality Squal or reception level Srxlev of each inter-frequency cell having a higher priority than the frequency of the serving cell can be derived based on SIB4 broadcast by the serving cell (according to Equation 1), and the reception quality Squal or reception level Srxlev of each inter-RAT cell having a higher priority than the frequency of the serving cell can be derived based on SIB5 broadcast by the serving cell (according to Equation 1). In addition, for an inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell, or for an inter-RAT cell having a frequency lower than the frequency of the serving cell, when the reception level Srxlev and the reception quality Squal of the serving cell measured in operation 3g-15 are lower than the threshold value (Srxlex≤SnonIntraSearchP and Squal≤SintraSearchQ), the UE in RRC idle mode or RRC inactive mode can measure the neighboring inter-frequency cell using a frequency different from the serving cell, or measure the neighboring inter-RAT cell using a RAT different from the serving cell (3g-20). That is, the reception quality Squal or the reception level Srxlev of at least one inter-frequency cell having a frequency equal to or lower than the frequency of the serving cell is derived based on SIB4 broadcast by the serving cell (according to Equation 1), and the reception quality Squal or the reception level Srxlev of at least one inter-RAT cell having a frequency lower than the frequency of the serving cell is derived based on SIB5 broadcast by the serving cell (according to Equation 1). For reference, information about the thresholds SnonIntraSearchP and SnonIntraSearchQ is included in SIB2.

[0553] A UE in RRC idle mode or RRC inactive mode can perform a cell reselection evaluation process (3g-25) based on cell reselection priority and / or ranking, based on the measurement values ​​of neighboring cells (obtained in 3g-20). That is, when multiple cells that meet the cell reselection criteria have different priorities, the reselection of a frequency / RAT cell with a higher priority precedes the reselection of a frequency / RAT cell with a lower priority (if multiple cells of different priorities meet the cell reselection criteria, the cell reselection for a higher priority RAT / frequency should precede the RAT / frequency with a lower priority). Priority information is included in the system information (SIB2, SIB4 and SIB5) broadcast by the serving cell, or is included in the RRCRelease message received when the UE transitions from RRC connected mode to RRC idle mode or RRC inactive mode. The information about priority included in the RRCRelease message may have priority over the information about priority included in the system information broadcast by the serving cell. The operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a higher priority than the frequency of the serving cell will now be described below.

[0554] -First operation:

[0555] *When SIB2 including the threshold threshServingLowQ is broadcast and 1 second has passed after the UE resides in the current serving cell, when the reception quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighQ during a specific time interval TreselectionRAT (Squal>ThreshX during the time interval TreselectionRAT), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0556] - Second operation:

[0557] *When the UE cannot perform the first operation, the UE may perform the second operation.

[0558] *When 1 second has passed after the UE camps on the current serving cell and the reception level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,HighP during a specific time interval TreselectionRAT (During the time interval TreselectionRAT, Srxlev>ThreshX,HighP), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0559] In this regard, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-frequency cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB4 broadcast by the serving cell). In addition, the UE may perform the first operation or the second operation based on the reception quality Squal of the inter-RAT cell, the reception level Srxlev, the thresholds ThrehX,HighQ and ThreshX,HighP, and the value of TreselectionRAT (ie, the information included in SIB5 broadcast by the serving cell).

[0560] Furthermore, the operation of a ranking-based cell reselection evaluation procedure of the UE for an intra-frequency cell belonging to the frequency of the current serving cell or an inter-frequency cell having a priority equal to the frequency of the current serving cell will now be described below.

[0561] -Third operation:

[0562] *When the reception quality Squal and reception level Srxlev of each intra-frequency / inter-frequency cell are greater than 0, the UE can derive the ranking of each cell based on the measurement value of RSRP (the UE should perform ranking on all cells that meet the cell selection criterion S). The ranking of the serving cell and the neighboring cell can be calculated separately by using the above equation 2.

[0563] In the aforementioned equation 2, Qmeas,s indicates the RSRP measurement value of the serving cell, Qmeas,n indicates the RSRP measurement value of the neighboring cell, Qhyst indicates the hysteresis value of the serving cell, and Qoffset indicates the offset between the serving cell and the neighboring cell. SIB2 includes the Qhyst value, and the Qhyst value can be used together to reselect the same-frequency / different-frequency cells. When reselecting the same-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB3. When reselecting the different-frequency cell, Qoffset is signaled according to each cell, applied only to the designated cell, and included in SIB4. When the ranking of the neighboring cell derived according to equation 2 is greater than the ranking of the serving cell (i.e., Rn>Rs), the UE can reside in the best cell among the neighboring cells.

[0564] Furthermore, the operation of the cell reselection evaluation procedure of the UE for an inter-frequency / inter-RAT cell having a lower priority than the frequency of the current serving cell will now be described below.

[0565] *562-Fourth Operation:

[0566] *When the UE broadcasts SIB2 including the threshold threshServingLowQ and 1 second has elapsed after the UE camps on the current serving cell, when the received quality Squal of the current serving cell is less than the threshold ThreshServing,LowQ (Squal < ThreshServing,LowQ), and the received quality Squal of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Squal > ThreshX,LowQ), the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0567] - Fifth operation:

[0568] *When the UE cannot perform the fourth operation, the UE may perform the fifth operation.

[0569] *When 1 second has elapsed after the UE camps on the current serving cell, the received level Srxlev of the current serving cell is lower than the threshold ThreshServing,LowP (Srxlev < ThreshServing,LowP), and the received level Srxlev of the inter-frequency or inter-RAT cell is higher than the threshold ThreshX,LowQ during a specific time interval TreselectionRAT (during the time interval TreselectionRAT, Srxlev > ThreshX,LowP), then the UE may perform reselection for the inter-frequency or inter-RAT cell.

[0570] In this regard, the fourth or fifth operation of the UE for the inter-frequency cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-frequency cell and the thresholds ThrehX,LowQ and ThreshX,LowP included in SIB4 broadcast by the serving cell. The fourth or fifth operation of the UE for the inter-RAT cell may be performed based on the thresholds ThreshServing,LowQ and ThreshServing,LowP included in SIB2 broadcast by the serving cell and the received quality Squal, received level Srxlev of the inter-RAT cell and the thresholds ThreshX,LowQ and ThreshX,LowP included in SIB5 broadcast by the serving cell. For example, SIB4 includes the Qqualmin value or the Qrxlevmin value, and the received quality Squal or received level Srxlev of the inter-frequency cell may be derived based on this value.

[0571] In 3g-30, the UE can derive a candidate cell list, and then can select a candidate target cell based on the priority and / or ranking from the candidate cell list. When selecting a candidate target cell, in 3g-35, a UE in RRC idle mode or RRC inactive mode can determine whether to select the corresponding cell by attempting to receive the MIB and SIB1 broadcast by the corresponding cell before the UE finally selects the corresponding cell. At this time, the UE performs the following operations.

[0572] When the selected candidate target cell broadcasts the MIB in 3g-35, the UE may attempt to receive the MIB in 3g-40.

[0573] When the UE cannot obtain the MIB, the UE can perform the sixth operation in 3g-45.

[0574] Sixth operation: The UE may consider the cell state of the corresponding cell to be barred, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds (the UE shall or may exclude the barred cell as a candidate for cell selection / reselection within up to 300 seconds). When the reception quality Squal and / or reception level Srxlev of another cell (the other cell uses the same frequency as the corresponding cell) derived according to Equation 1 is greater than 0 and / or satisfies the cell reselection criteria, the UE may select the other cell (if the selection criteria and / or cell reselection criteria are met, the UE may select another cell on the same frequency).

[0575] When the UE receives the MIB (upon receiving the MIB), the UE may determine whether the corresponding cell satisfies the first condition or the second condition based on the information included in the MIB (3g-50).

[0576] First condition: when a cellBarred field value included in the received MIB is set to 'barred' and / or PDCCH-ConfigSIB1 is not supported.

[0577] Second condition: a condition that does not correspond to the first condition

[0578] Seventh operation: When the first condition is met, in 3g-55, the UE may consider the corresponding cell as a prohibited cell, and may exclude the prohibited cell from the candidate cell list for cell selection / reselection within 300 seconds. When the value of the intraFreqReselection field included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells that use the same frequency as the prohibited cell within 300 seconds. When the value of the intraFreqReselection field included in the MIB is set to "allowed", when the (multiple) cells meet the cell reselection criteria, the UE may select the (multiple) cells, and the (multiple) cells use the same frequency as the prohibited cell.

[0579] Eighth operation: When the second condition is met, in 3g-60, the UE may consider the corresponding cell as an allowed cell, and may determine the corresponding cell as a candidate cell for cell selection / reselection. When the intraFreqReselection field value included in the MIB is set to "notAllowed", the UE may not select / reselect (multiple) cells that use the same frequency as the cell within 300 seconds. When the intraFreqReselection field value included in the MIB is set to "allowed", when the (multiple) cells meet the cell reselection criteria, the UE may select the (multiple) cells, and the (multiple) cells use the same frequency as the cell.

[0580] When the selected candidate target cell broadcasts SIB1 in 3g-35, the UE may attempt to receive SIB1 in 3g-65.

[0581] When the UE cannot obtain SIB1, the UE can perform the seventh operation described in 3g-55 in 3g-70.

[0582] When the UE receives SIB1 (upon receiving SIB1), the UE may determine whether the corresponding cell satisfies the third condition or the fourth condition (3g-75) based on the information included in the MIB and SIB1. The third condition and the fourth condition are as follows.

[0583] Third condition: When the UE identifies the SCS value configured in subCarrierSpacingCommon of the received MIB and does not support the bandwidth of the initial DLBWP and the bandwidth of the initial UL BWP using the SCS value configured in locationAndBandwidth in the received SIB1

[0584] Fourth condition: When the UE identifies the SCS value configured in subCarrierSpacingCommon of the received MIB and supports the bandwidth of the initial DLBWP and the bandwidth of the initial UL BWP using the SCS value in the configured locationAndBandwidth in the received SIB1 (if the UE supports the bandwidth of the initial DL / UL BWP in locationAndBandwidth in SIB1)

[0585] Ninth operation: When the third condition is met, in 3G-80, the UE may determine that the corresponding cell is inaccessible or may consider the corresponding cell to be a prohibited cell, and may exclude the corresponding cell from the candidate cell list for cell selection / reselection within 300 seconds. The UE may not select / reselect (multiple) cells using the same frequency as the prohibited cell within 300 seconds.

[0586] Tenth operation: When the fourth condition is met, in 3g-85, the UE may determine that the corresponding cell is accessible. Then, the UE may derive the reception quality Squal and / or reception level Srxlev of the corresponding cell based on the information included in SIB1 by using equation 1, and when the reception quality Squal and / or reception level Srxlev satisfies the S criterion (Srxlev>0 and / or Squal>0), the UE may finally reselect the corresponding cell, otherwise, the UE may not finally reselect the corresponding cell.

[0587] Figure 3H A block diagram of a UE according to an embodiment of the present disclosure is shown.

[0588] refer to Figure 3H , the UE may include a radio frequency (RF) processor 3h-10, a baseband processor 3h-20, a storage device 3h-30, and a controller 3h-40. The UE according to an embodiment of the present disclosure may perform operations to implement the above reference Figures 1A to 3G Embodiments of the present disclosure are described.

[0589] The RF processor 3h-10 can perform functions for sending and receiving signals through wireless channels, such as frequency band conversion and amplification of signals. That is, the RF processor 3h-10 can up-convert the baseband signal provided from the baseband processor 3h-20 into an RF band signal, and then can send the RF band signal through the antenna, and can down-convert the RF band signal received through the antenna into a baseband signal. For example, the RF processor 3h-10 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc.

[0590] Despite Figure 3HOnly one antenna is shown in the figure, but the UE may include multiple antennas. The RF processor 3h-10 may include multiple RF chains. The RF processor 3h-10 can perform beamforming. For beamforming, the RF processor 3h-10 can adjust the phase and strength of the signal to be sent or received through multiple antennas or antenna elements. The RF processor 3h-10 can perform multiple-input multiple-output (MIMO) operations and can receive multiple layers of data in MIMO operations.

[0591] The baseband processor 3h-20 can convert between baseband signals and bit streams based on the physical layer specifications of the system. For example, for data transmission, the baseband processor 3h-20 generates complex symbols by encoding and modulating the transmitted bit stream. For data reception, the baseband processor 3h-20 can reconstruct the received bit stream by demodulating and decoding the baseband signal provided from the RF processor 3h-10. For example, according to the OFDM scheme, for data transmission, the baseband processor 3h-20 generates complex symbols by encoding and modulating the transmitted bit stream, maps the complex symbols to subcarriers, and then configures OFDM symbols by performing an inverse fast Fourier transform (IFFT) and cyclic prefix (CP) insertion. For data reception, the baseband processor 3h-20 can segment the baseband signal provided from the RF processor 3h-10 into OFDM symbol units, can reconstruct the signal mapped to the subcarrier by performing a fast Fourier transform (FFT), and can then reconstruct the received bit stream by demodulating and decoding the signal.

[0592] The baseband processor 3h-20 and the RF processor 3h-10 send and receive signals as described above. The baseband processor 3h-20 and the RF processor 3h-10 may also be referred to as a transmitter, a receiver, a transceiver, or a communicator. At least one of the baseband processor 3h-20 or the RF processor 3h-10 may include a plurality of communication modules to support a variety of different radio access technologies. At least one of the baseband processor 3h-20 or the RF processor 3h-10 may include different communication modules to process signals of different frequency bands. For example, different radio access technologies may include a wireless local area network (WLAN) (e.g., IEEE 802.11), a cellular network (e.g., LTE), and the like. Different frequency bands may include ultra-high frequency (SHF) (e.g., 2NRHz or 1NRHz) bands and millimeter wave (mmWave) (e.g., 60GHz) bands.

[0593] The storage device 3h-30 stores basic programs, applications, and data (e.g., configuration information) for the operation of the UE. Specifically, the storage device 3h-30 can store information about a second access node configured to perform wireless communication by using a second radio access technology. The storage device 3h-30 can provide stored data upon request from the controller 3h-40.

[0594] The controller 3h-40 can control the overall operation of the UE. For example, the controller 3h-40 can send and receive signals through the baseband processor 3h-20 and the RF processor 3h-10. The controller 3h-40 can record data on the storage device 3h-30 and read data from the storage device 3h-30. In this regard, the controller 3h-40 may include at least one processor. For example, the controller 3h-40 may include a communication processor for controlling communications and an application processor (AP) for controlling an upper layer such as an application.

[0595] The controller 3h-40 may include a multi-connection processor 3h-42 for performing processing to operate in a multi-connection mode.

[0596] Fig. 3I is a block diagram of a BS according to an embodiment of the present disclosure.

[0597] refer to Fig. 3I , the BS may include an RF processor 3i-10, a baseband processor 3i-20, a backhaul communicator 3i-30, a storage device 3i-40 and a controller 3i-50.

[0598] The BS according to an embodiment of the present disclosure may perform operations to implement the above reference Figures 1A to 3G Embodiments of the present disclosure are described.

[0599] The RF processor 3i-10 can perform functions for sending and receiving signals through a wireless channel, such as frequency band conversion and amplification of signals. The RF processor 3i-10 can up-convert the baseband signal provided by the baseband processor 3i-20 into an RF band signal, which can then be transmitted through an antenna, and can down-convert the RF band signal received through an antenna into a baseband signal. For example, the RF processor 3i-10 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc. Although in Fig. 3I Only one antenna is shown in the figure, but BS 3i ​​may include multiple antennas. RF processor 3i-10 may include multiple RF chains. In addition, RF processor 3i-10 may perform beamforming. For beamforming, RF processor 3i-10 may adjust the phase and strength of a signal to be sent or received through multiple antennas or antenna elements. RF processor 3i-10 may perform DL MIMO operations by sending data of one or more layers.

[0600] The baseband processor 3i-20 can convert between baseband signals and bit streams based on the physical layer specifications of the first radio access technology. For example, for data transmission, the baseband processor 3i-20 can generate complex symbols by encoding and modulating the transmitted bit stream. For data reception, the baseband processor 3i-20 can reconstruct the received bit stream by demodulating and decoding the baseband signal provided from the RF processor 3i-10. For example, according to the OFDM scheme, for data transmission, the baseband processor 3i-20 can generate complex symbols by encoding and modulating the transmitted bit stream, the complex symbols can be mapped to subcarriers, and then OFDM symbols can be configured by performing IFFT and CP insertion. For data reception, the baseband processor 3i-20 can segment the baseband signal provided from the RF processor 3i-10 into OFDM symbol units, the signal mapped to the subcarrier can be reconstructed by performing FFT, and then the received bit stream can be reconstructed by demodulating and decoding the signal. The baseband processor 3i-20 and the RF processor 3i-10 can send and receive signals as described above. In this way, the baseband processor 3i-20 and the RF processor 3i-10 can also be called a transmitter, a receiver, a transceiver, a communicator or a wireless communicator.

[0601] The backhaul communicator 3i-30 can provide an interface for communicating with other nodes in the network. That is, the backhaul communicator 3i-30 can convert a bit stream to be sent from the BS to another node (e.g., a secondary BS or a core network) into a physical signal, and convert a physical signal received from another node into a bit stream.

[0602] The storage device 3i-40 can store basic programs, applications and data, such as configuration information, for the operation of the BS. Specifically, the storage device 3i-40 can store, for example, information about the bearer allocated to the connected UE and the measurement results reported from the connected UE. The storage device 3i-40 can store standard information for determining whether to provide dual connectivity to the UE or release dual connectivity from the UE. The storage device 3i-40 can provide the stored data according to the request of the controller 3i-50.

[0603] The controller 3i-50 may control the overall operation of the BS. For example, the controller 3i-50 may send and receive signals through the baseband processor 3i-20 and the RF processor 3i-10 or the backhaul communicator 3i-30. The controller 3i-50 may record data on the storage device 3i-40 and read data from the storage device 3i-40. To this end, the controller 3i-50 may include at least one processor.

[0604] The methods according to the embodiments of the present disclosure as described herein or in the accompanying claims may be implemented as hardware, software, or a combination of hardware and software.

[0605] When implemented as software, a computer-readable storage medium storing one or more programs (e.g., software modules) may be provided. One or more programs stored in the computer-readable storage medium are configured to be executed by one or more processors in an electronic device. One or more programs include instructions that instruct the electronic device to perform a method according to an embodiment of the present disclosure as described herein or in the appended claims.

[0606] The program (e.g., software module or software) may be stored in a non-volatile memory, including random access memory (RAM) or flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), a magnetic disk storage device, a compact disk (CD)-ROM, a digital versatile disk (DVD), another optical storage device, or a magnetic tape cassette. Alternatively, the program may be stored in a memory comprising a combination of some or all of the above storage media. A plurality of such memories may be included.

[0607] In addition, the program can be stored in an attachable storage device, wherein the storage device can be accessed through any one or combination of communication networks such as the Internet, an intranet, a local area network (LAN), a wide LAN (WLAN), and a storage area network (SAN). Such a storage device can access the electronic device via an external port. In addition, an additional storage device on a communication network can access the electronic device.

[0608] According to an embodiment of the present disclosure, information about the capabilities of a UE can be easily provided in a mobile communication system. According to an embodiment of the present disclosure, a UE can perform a resource request by using multiple scheduling requests according to the characteristics of a service and the reason for sending a resource request, and thus can be allocated UL resources in a timely manner and then can send data. According to an embodiment of the present disclosure, in a mobile communication system, in response to channel bandwidth signaling, a UE can effectively perform cell reselection.

[0609] In the above-mentioned embodiment of the present disclosure, according to the embodiment of the present disclosure, one or more elements included in the present disclosure are expressed in singular or plural form. However, the singular or plural form is appropriately selected for the situation assumed for the convenience of description, the present disclosure is not limited to the singular or plural form, and the element expressed in the singular form may include multiple elements, and the element expressed in the plural form may include a single element.

[0610] Although the present disclosure has been described with various embodiments, various changes and modifications may occur to those skilled in the art. The present disclosure is intended to encompass such changes and modifications as fall within the scope of the appended claims.

Claims

1. A user equipment UE, comprising: Transceiver; and The processor is configured as: receiving, via the transceiver, a first message requesting UE capability information from a base station, determining the UE capability field of the UE capability information to include values ​​applicable to all duplex modes and frequency ranges supported by the UE, Among them, when the UE supports frequency range 1FR1 and frequency range 2FR2: In case the UE supports additional functionality of FR1 compared to the functionality indicated by the determined UE capabilities field, the FR1 additional UE capabilities field is included in the UE capabilities information, and is configured to include fields reflecting the additional functionality of FR1, and In the event that the UE supports additional functionality of FR2 compared to the functionality indicated by the determined UE capabilities field, a FR2 additional UE capabilities field is included in the UE capabilities information and is set to include a field reflecting the additional functionality of FR2, and A second message including the UE capability information is sent to the base station via the transceiver as a response to the first message.

2. The UE according to claim 1, wherein: In the case where the UE supports frequency division duplex FDD and time division duplex TDD functions, and the UE supports additional functions of the FDD compared to the functions indicated by the determined UE capability field, an FDD additional UE capability field is included in the UE capability information, and the FDD additional UE capability field is set to include a field reflecting the additional functions of the FDD.

3. The UE according to claim 1, wherein: In the case where the UE supports frequency division duplex FDD and time division duplex TDD functions, and the UE supports additional functions of the TDD compared to the functions indicated by the determined UE capability field, the TDD additional UE capability field is included in the UE capability information, and the TDD additional UE capability field is set to include a field reflecting the additional functions of the TDD.

4. The UE according to claim 1, wherein: The duplex mode includes frequency division duplex FDD and time division duplex TDD, and The frequency range includes FR1 and FR2.

5. A base station for performing communication, the base station comprising: Transceiver; and The processor is configured as: sending a first message requesting UE capability information to a user equipment UE via the transceiver, and receiving, via the transceiver, from the UE as a response to the first message, a second message including UE capability information, wherein the UE capability information includes a UE capability field, the UE capability field being set to include a value applicable to all duplex modes and frequency ranges supported by the UE, Among them, when the UE supports frequency range 1FR1 and frequency range 2FR2: In the case where additional functionality of the FR1 is supported at the UE compared to functionality indicated by the UE capability field, the UE capability information includes a FR1 additional UE capability field, the FR1 additional UE capability field being set to include a field reflecting the additional functionality of the FR1, and In case the FR2 additional functionality is supported at the UE compared to the functionality indicated by the UE capability field, the UE capability information includes a FR2 additional UE capability field, which is set to include a field reflecting the FR2 additional functionality.

6. The base station according to claim 5, wherein: In a case where frequency division duplex FDD and time division duplex TDD are supported at the UE, and additional functions of the FDD are supported at the UE compared to the functions indicated by the UE capability field, the UE capability information includes an FDD additional UE capability field, and the FDD additional UE capability field is set to include a field reflecting the additional functions of the FDD.

7. The base station according to claim 5, wherein: In a case where frequency division duplex FDD and time division duplex TDD are supported at the UE, and additional functions of the TDD are supported at the UE compared to the functions indicated by the UE capability field, the UE capability information includes a TDD additional UE capability field, and the TDD additional UE capability field is set to include a field reflecting the additional functions of the TDD.

8. The base station according to claim 5, wherein: The duplex mode includes frequency division duplex FDD and time division duplex TDD, and The frequency range includes FR1 and FR2.

9. A method performed by a user equipment UE, the method comprising: receiving, from a base station, a first message requesting UE capability information; determining a UE capability field of the UE capability information to include values ​​applicable to all duplex modes and frequency ranges supported by the UE; Among them, when the UE supports frequency range 1FR1 and frequency range 2FR2: In the event that the UE supports additional functionality of FR1 compared to the functionality indicated by the determined UE capabilities field, a FR1 additional UE capabilities field is included in the UE capability information and is set to include a field reflecting the additional functionality of FR1, and In the event that the UE supports additional functionality of FR2 compared to the functionality indicated by the determined UE capabilities field, a FR2 additional UE capabilities field is included in the UE capabilities information and is set to include a field reflecting the additional functionality of FR2, and A second message including the UE capability information is sent to the base station as a response to the first message.

10. The method according to claim 9, wherein: In the case where the UE supports frequency division duplex FDD and time division duplex TDD functions, and the UE supports additional functions of the FDD compared to the functions indicated by the determined UE capability field, an FDD additional UE capability field is included in the UE capability information, and the FDD additional UE capability field is set to include a field reflecting the additional functions of the FDD.

11. The method according to claim 9, wherein: In the case where the UE supports frequency division duplex FDD and time division duplex TDD functions, and the UE supports additional functions of the TDD compared to the functions indicated by the determined UE capability field, the TDD additional UE capability field is included in the UE capability information, and the TDD additional UE capability field is set to include a field reflecting the additional functions of the TDD.

12. The method according to claim 9, wherein: The duplex mode includes frequency division duplex FDD and time division duplex TDD, and The frequency range includes FR1 and FR2.

13. A method performed by a base station, the method comprising: Sending a first message requesting UE capability information to a user equipment UE; as well as receiving, as a response to the first message, a second message from the UE including UE capability information, wherein the UE capability information includes a UE capability field, the UE capability field being set to include a value applicable to all duplex modes and frequency ranges supported by the UE, Among them, when the UE supports frequency range 1FR1 and frequency range 2FR2: In the case where additional functionality of the FR1 is supported at the UE compared to functionality indicated by the UE capability field, the UE capability information includes a FR1 additional UE capability field, the FR1 additional UE capability field being set to include a field reflecting the additional functionality of the FR1, and In case the FR2 additional functionality is supported at the UE compared to the functionality indicated by the UE capability field, the UE capability information includes a FR2 additional UE capability field, which is set to include a field reflecting the FR2 additional functionality.

14. The method according to claim 13, wherein: In a case where frequency division duplex FDD and time division duplex TDD are supported at the UE, and additional functions of the FDD are supported at the UE compared to the functions indicated by the UE capability field, the UE capability information includes an FDD additional UE capability field, and the FDD additional UE capability field is set to include a field reflecting the additional functions of the FDD.

15. The method according to claim 13, wherein: In a case where frequency division duplex FDD and time division duplex TDD are supported at the UE, and additional functions of the TDD are supported at the UE compared to the functions indicated by the UE capability field, the UE capability information includes a TDD additional UE capability field, and the TDD additional UE capability field is set to include a field reflecting the additional functions of the TDD.

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