Method and apparatus for reporting UE capabilities of a terminal in a next generation mobile communication system

Abstract

Provided is a communication technology and system for merging a fifth generation (5G) communication system for supporting higher data rates after a fourth generation (4G) system with an Internet of Things (IoT) technology. The present disclosure can be applied to smart services based on 5G communication technology and IoT-related technologies (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail, security and safety-related services, etc.). Provided is a method and device for reporting the capabilities of a user equipment (UE) of a terminal.

Description

Technical Field

[0001] The present disclosure relates to operations of a terminal and a base station in a mobile communication system.

[0002] More specifically, the present disclosure relates to a mobile communication system, and more specifically, to a method for a terminal to report its own user equipment (UE) capabilities. In addition, the present disclosure proposes a general terminal reporting process when the terminal receives or does not receive a request for reporting UE capabilities from a base station under multiple radio access technologies, and includes a process that can reflect temporary changes in terminal capabilities. Background Art

[0003] In order to meet the increased demand for wireless data services after the commercialization of the fourth generation (4G) communication system, efforts have been made to develop an improved fifth generation (5G) communication system or a pre-5G communication system. For this reason, the 5G communication system or the pre-5G communication system is referred to as a super 4G network communication system or a post-long term evolution (LTE) system.

[0004] In order to achieve high data transmission rates, 5G communication systems are being considered for implementation in millimeter wave (mmWave) bands (e.g., 60 GHz bands). In 5G communication systems, technologies such as beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antennas are being discussed as means to mitigate propagation path losses in millimeter wave bands and increase propagation transmission distances.

[0005] In addition, 5G communication systems have developed technologies such as evolved small cells, advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device communications (D2D), wireless backhaul, mobile networks, cooperative communications, coordinated multi-point (CoMP), and reception interference cancellation to improve system networks. In addition, 5G systems have developed advanced coding modulation (ACM) schemes such as hybrid frequency shift keying (FSK) and quadrature amplitude modulation (QAM) (FQAM) and sliding window superposition coding (SWSC), as well as advanced access technologies such as filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA).

[0006] At the same time, the Internet has evolved from a human-oriented connected network in which humans generate and consume information to an Internet of Things (IoT) network in which distributed components (such as objects) exchange and process information. Among them, the Internet of Everything (IoE) technology, which combines big data processing technology connected to cloud servers and the like with IoT technology, has emerged.

[0007] In order to implement IoT, technical factors such as detection technology, wired / wireless communication, network infrastructure, service interface technology, and security technology are required, and research on technologies such as sensor networks, machine-to-machine (M2M) communication, machine type communication (MTC), etc. for connection between objects has been conducted recently. In the IoT environment, by collecting and analyzing data generated in networked objects, smart Internet technology (IT) services can be provided to create new value for people's lives. IoT can be applied to various fields such as smart homes, smart buildings, smart cities, smart cars, connected cars, smart grids, healthcare, smart appliances, or high-tech medical services through the integration of information technology (IT) in related fields and various industries.

[0008] Therefore, various attempts have been made to apply 5G communication to IoT networks. For example, 5G communication technologies such as sensor networks, machine-to-machine (M2M) communication, and machine-type communication (MTC) have been implemented through technologies such as beamforming, MIMO, and array antennas. The application of cloud RAN as a big data processing technology can be an example of the fusion of 5G technology and IoT technology.

[0009] The above information is provided as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with respect to the present disclosure. Summary of the invention

[0010] Technical issues

[0011] In addition to the method of reporting the UE capabilities of the terminal itself according to a request from a base station, the present disclosure also considers a method in which a new radio (NR) terminal can request base station management suitable for the current UE capabilities by reporting temporary UE capabilities about temporary changes in the UE capabilities of the terminal to the base station. In the existing process, only when the terminal receives a request for a UE capability report from the base station through a radio resource control (RRC) message, the terminal generates UE capabilities for the indicated radio access technology (RAT) type according to the request of the base station, and sends the UE capabilities to the base station using a message reporting the UE capabilities. However, in the case where the UE capabilities are temporarily changed due to hardware and interference problems inside the terminal, there is no process to reflect this situation. Therefore, the operation of the terminal and the base station in the mobile communication system is required.

[0012] Solution to the problem

[0013] Aspects of the present disclosure are to address at least the above-mentioned problems and / or disadvantages and to provide at least the advantages described below. Therefore, one aspect of the present disclosure is to provide operations of a terminal and a base station in a mobile communication system.

[0014] 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.

[0015] According to one aspect of the present disclosure, a method performed by a terminal in a wireless communication system is provided. The method includes: receiving a first message including configuration information associated with overheating from a base station, identifying whether internal overheating is detected, and, if internal overheating is detected, reporting to the base station a second message including overheating assistance information based on the configuration information, wherein the overheating assistance information includes information about at least one of the number of component carriers, bandwidth, and the number of multiple-input multiple-output (MIMO) layers.

[0016] According to another aspect of the present disclosure, a method performed by a base station in a wireless communication system is provided. The method includes: sending a first message including configuration information associated with overheating to a terminal, and receiving a second message including overheating assistance information based on the configuration information from the terminal, wherein the overheating assistance information includes information about at least one of the number of component carriers, bandwidth, and the number of MIMO layers.

[0017] According to another aspect of the present disclosure, a terminal in a wireless communication system is provided. The terminal includes a transceiver and at least one processor, the at least one processor being configured to: receive a first message including configuration information associated with overheating from a base station via the transceiver, identify whether internal overheating is detected, and, if internal overheating is detected, report a second message including overheating assistance information based on the configuration information to the base station via the transceiver, wherein the overheating assistance information includes information about at least one of the number of component carriers, bandwidth, and the number of MIMO layers.

[0018] According to another aspect of the present disclosure, a base station in a wireless communication system is provided. The base station includes a transceiver and at least one processor, the at least one processor being configured to: send a first message including configuration information associated with overheating to a terminal via the transceiver, and receive a second message including overheating assistance information based on the configuration information from the terminal via the transceiver, wherein the overheating assistance information includes information about at least one of the number of component carriers, bandwidth, and the number of MIMO layers.

[0019] Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses various embodiments of the disclosure.

[0020] Advantageous Effects of the Invention

[0021] According to an embodiment of the present disclosure, a method and apparatus for reporting user equipment (UE) capabilities may be provided.

[0022] In addition, according to an embodiment of the present disclosure, in addition to a method for reporting the UE capabilities of the terminal itself according to a request from a base station, a method can also be provided in which the terminal can request management suitable for the current UE capabilities from the base station by reporting to the base station temporary UE capabilities according to temporary changes in the UE capabilities of the terminal.

[0023] In addition, according to an embodiment of the present disclosure, in addition to the case where the terminal receives a request for a UE capability report from the base station through an RRC message, the new radio (NR) terminal can actively report to the base station the UE capability that has changed due to a temporary change in the UE capability, etc., thereby sending a dynamic UE capability report to the base station. Accordingly, the base station can perform more appropriate resource allocation and terminal management for the terminal, and the terminal can also obtain performance that conforms to the actual UE capability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0025] Figure 1 is a diagram showing a structure of a Long Term Evolution (LTE) system according to an embodiment of the present disclosure;

[0026] Figure 2 is a diagram showing a radio protocol structure in an LTE system according to an embodiment of the present disclosure;

[0027] Figure 3 is a diagram showing a structure of a next generation mobile communication system according to an embodiment of the present disclosure;

[0028] Figure 4 is a diagram showing a radio protocol structure of a next generation mobile communication system according to an embodiment of the present disclosure;

[0029] Figure 5 is a diagram showing the structure of a message for reporting user equipment (UE) capabilities in a New Radio (NR) system according to an embodiment of the present disclosure;

[0030] Figure 6 is a diagram illustrating a method in which a terminal in a radio resource control (RRC) connected state requests a temporary change in UE capabilities according to an embodiment of the present disclosure;

[0031] Figure 7 is a diagram illustrating a method for a terminal in an RRC connected state to request a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0032] Figure 8 is a diagram illustrating a method for a terminal in an RRC idle state to request a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0033] Fig. 9 is a diagram illustrating a method for a terminal in an RRC idle state to request a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0034] Fig.10 is a diagram illustrating a method for a terminal in an RRC idle state to request a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0035] Fig.11 is a diagram illustrating a method for a terminal in an RRC idle state to request a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0036] Fig.12 is a diagram illustrating a method for a terminal in an RRC idle state to request a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0037] Fig.13 is a diagram illustrating a method for a terminal in an RRC inactive state to request a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0038] Fig.14 is a diagram illustrating a method for a terminal in an RRC inactive state to request a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0039] Fig.15 is a diagram illustrating a method for a terminal in an RRC inactive state to request a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0040] Fig.16 is a diagram showing an overall operation of a terminal in an RRC connected state requesting a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0041] Fig.17 is a diagram showing an overall operation of a terminal in an idle or inactive state requesting a temporary change of UE capabilities according to an embodiment of the present disclosure;

[0042] Fig.18 is a diagram illustrating the overall operation of a base station receiving a temporary UE capability change of a terminal according to an embodiment of the present disclosure;

[0043] Fig.19 is a diagram showing a configuration of a terminal according to an embodiment of the present disclosure; and

[0044] Fig. 20 is a diagram showing a configuration of a base station according to an embodiment of the present disclosure.

[0045] Throughout the drawings, like reference numerals will be understood to refer to like parts, components and structures. DETAILED DESCRIPTION

[0046] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of the various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details that aid in understanding, but these are considered to be exemplary only. Therefore, it will be appreciated by those of ordinary skill in the art that various changes and modifications may be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, for the sake of clarity and conciseness, descriptions of well-known functions and structures may be omitted.

[0047] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present disclosure. Therefore, it is apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustrative purposes only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents.

[0048] It should be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.

[0049] Hereinafter, the terms used to identify access nodes, terms related to network entities, terms related to messages, terms related to interfaces between network entities, terms related to various identification information, etc. are illustrative words for convenience of explanation. Therefore, the present disclosure is not limited to the terms described below, and other terms with equivalent technical meanings may be used.

[0050] Hereinafter, for convenience of explanation, terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) standard will be used. However, the present disclosure is not limited to the above terms and names, and can be applied to systems conforming to other standards in the same manner.

[0051] In the following description, a base station is an entity that performs resource allocation with respect to a terminal, and may be at least one of a gNode B (gNB), an eNode B (eNB), a Node B, a base station (BS), a radio access unit, a base station controller, and a node in a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, a downlink (DL) is a wireless transmission path for a signal sent from a base station to a terminal, and an uplink (UL) is a wireless transmission path for a signal sent from a terminal to a base station. In addition, although the embodiments of the present disclosure will be described below based on an NR system, the embodiments of the present disclosure may be applied to other communication systems having a similar technical background or channel form. In addition, without departing from the scope of the present disclosure, the embodiments of the present disclosure may be applied to other communication systems with some modifications according to the determination of those skilled in the art,

[0052] In the present disclosure, the terms "physical channel" and "signal" may be used interchangeably with "data" or "control signal." For example, although the physical downlink shared channel (PDSCH) is a physical channel for transmitting data, in the present disclosure, the PDSCH may be referred to as "data."

[0053] In the following embodiments of the present disclosure, high-layer signaling may be a method of sending a signal from a base station to a terminal using a downlink data channel of a physical layer or sending a signal from a terminal to a base station using an uplink data channel of a physical layer, and may also be referred to as "RRC signaling" or "Media Access Control (MAC) Control Element (CE)".

[0054] Figure 1 is a diagram showing the structure of an LTE system according to an embodiment of the present disclosure.

[0055] refer to Figure 1 As shown in the figure, the radio access network of the LTE system includes next-generation base stations (evolved Node B) (hereinafter, referred to as "eNB", "Node B" or "base station") 1a-05, 1a-10, 1a-15 and 1a-20, mobility management entity (MME) 1a-25 and serving gateway (S-GW) 1a-30. User equipment (hereinafter, referred to as "UE" or "terminal") 1a-35 accesses the external network through eNB 1a-05, 1a-10, 1a-15 and 1a-20 and S-GW 1a-30.

[0056] exist Figure 1In the LTE system, eNBs 1a-05, 1a-10, 1a-15, and 1a-20 correspond to existing Node Bs of the Universal Mobile Telecommunications System (UMTS). The eNBs are connected to UEs 1a-35 via radio channels and play a more complex role than existing Node Bs. In the LTE system, since all user traffic including real-time services such as Voice over IP (VoIP) over Internet Protocol is served through a shared channel, a device for collecting status information such as a buffer status of the UE, an available transmission power status, and a channel status and performing scheduling is required. eNBs 1a-05, 1a-10, 1a-15, and 1a-20 serve as such devices.

[0057] One eNB usually controls multiple cells. For example, in order to achieve a data rate of 100Mbps, the LTE system uses, for example, orthogonal frequency division multiplexing (hereinafter referred to as "OFDM") in a 20MHz bandwidth as a radio access technology. In addition, an adaptive modulation and coding (hereinafter referred to as "AMC") scheme is applied to determine the modulation scheme and channel coding rate according to the channel state of the terminal. S-GW 1a-30 is a device for providing data bearers, and generates or removes data bearers under the control of MME 1a-25. MME 1a-25 is a device that performs various control functions and mobility management functions of the terminal, and is connected to multiple base stations 1a-05, 1a-10, 1a-15 and 1a-20.

[0058] Figure 2 is a diagram showing a radio protocol structure in an LTE system according to an embodiment of the present disclosure.

[0059] refer to Figure 2 , the radio protocols of the LTE system include the Packet Data Convergence Protocol (PDCP) 1b-05 or 1b-40, Radio Link Control (RLC) 1b-10 or 1b-35, and Medium Access Control (MAC) 1b-15 or 1b-30 in the terminal and eNB, respectively. PDCP 1b-05 or 1b-40 performs operations such as IP header compression / decompression. The main functions of PDCP are summarized as follows.

[0060] -Header compression and decompression (ROHC only)

[0061] -Transfer of user data

[0062] - In-sequence delivery of higher layer packet data units (PDUs) during PDCP re-establishment in RLC Acknowledged Mode (AM)

[0063] -Sequence reordering (for split bearers in DC (supports RLC AM only): PDCP PDU routing for transmission, and PDCP PDU reordering for reception)

[0064] - Duplicate detection of lower layer service data units (SDUs) during PDCP re-establishment of RLC AM

[0065] - For RLC AM, retransmit PDCP SDUs at handover and for split bearers in DC, retransmit PDCP PDUs during PDCP data recovery

[0066] -Encryption and decryption

[0067] - Timer based SDU discard in uplink.

[0068] Radio Link Control (hereinafter, referred to as "RLC") 1b-10 or 1b-35 reconfigures a PDCP PDU (Packet Data Unit) into an appropriate size and performs an Automatic Repeat Query (ARQ) operation, etc. The main functions of the RLC are summarized as follows.

[0069] -Data transfer function (transmission of high-level PDU)

[0070] -ARQ function (error correction through ARQ (only for AM data transmission))

[0071] - RLC SDU splicing, segmentation and reassembly (only for UM and AM data delivery)

[0072] - Re-segmentation of RLC data PDU (only for AM data delivery)

[0073] - Reordering of RLC data PDUs (only for UM and AM data delivery)

[0074] - Duplicate detection (for UM and AM data delivery only)

[0075] -Protocol error detection (for AM data transfer only)

[0076] -RLC SDU discard (only for UM and AM data delivery)

[0077] -RLC reconstruction

[0078] MAC 1b-15 or 1b-30 is connected to a plurality of RLC entities configured in a terminal or a base station, multiplexes RLC PDUs into MAC PDUs, and demultiplexes RLC PDUs from MAC PDUs. The main functions of MAC are summarized as follows.

[0079] - Mapping between logical channels and transport channels

[0080] - Multiplexing / demultiplexing MAC SDUs belonging to one or different logical channels to / from transport blocks (TBs) delivered to / from the physical layer on transport channels

[0081] -Dispatch information report

[0082] -Hybrid ARQ (HARQ) functionality (error correction via HARQ)

[0083] - Priority handling between logical channels of a UE

[0084] - Priority handling between UEs through dynamic scheduling

[0085] -Multimedia Broadcast Multicast Service (MBMS) service identifier

[0086] -Transmission format selection

[0087] -filler

[0088] The physical layers 1b-20 and 1b-25 channel encode and modulate the high-layer data, convert it into OFDM symbols, and then send it through the radio channel, or demodulate the OFDM symbols received through the radio channel, channel decode them, and then send them to the high layer. In addition, hybrid ARQ (HARQ) is also used for additional error correction in the physical layer, and the receiving end sends 1-bit information indicating whether the packet sent from the transmitting end has been received. This is called HARQ acknowledgement (ACK) / negative acknowledgement (NACK) information. Downlink HARQ ACK / NACK information about uplink transmission can be sent through the physical hybrid ARQ indication channel (PHICH), and uplink HARQ ACK / NACK information about downlink transmission can be sent through the physical uplink control channel (PUCCH) or the physical uplink shared channel (PUSCH).

[0089] Meanwhile, the PHY layer may include one or more frequencies / carriers, and a technology for configuring and using multiple frequencies at the same time is called "carrier aggregation" (hereinafter referred to as "CA"). The CA technology may use a main carrier and one or more subcarriers, instead of one carrier, for communication between a terminal {or user equipment (UE)} and a base station (E-UMTS Terrestrial Radio Access Network (UTRAN) Node B or eNB), thereby significantly increasing the transmission volume in proportion to the number of subcarriers. Meanwhile, in the LTE system, a cell in a base station using a main carrier is called a "primary cell (PCell)", and a subcarrier is called a "secondary cell (SCell)".

[0090] Although not shown, a radio resource control (RRC) layer is provided on the PDCP layers of the terminal and the base station, respectively, and the RRC layer may transmit and receive control messages related to access and measurement of radio resource control.

[0091] Figure 3 is a diagram showing a structure of a next generation mobile communication system according to an embodiment of the present disclosure.

[0092] refer to Figure 3 , the radio access network of the next generation mobile communication system includes a new radio node B (hereinafter referred to as "NR NB") 1c-10 and a new radio core network (NR CN) {or next generation core network (NG CN)} 1c-05. The new radio user equipment (hereinafter referred to as "NR UE" or "terminal") 1c-15 accesses the external network 1c-20 through the NR NB 1c-10 and the NR CN 1c-05. The NR CN 1c-05 can be used interchangeably with "5G core network (5G CN)" or "5G core (5GC)".

[0093] exist Figure 3 In the present invention, NR NB 1c-10 corresponds to the evolved Node B in the existing LTE system. NR NB is connected to NR UE 1c-15 through a radio channel and can provide services superior to those of the existing Node B. In the next generation mobile communication system, since all user services are served through a shared channel, a device for collecting status information (such as the buffer status of the UE, the available transmission power status, and the channel status) and performing scheduling is required. NR NB 1c-10 serves as such a device.

[0094] One NR NB usually controls multiple cells. In order to achieve ultra-high data rates compared to existing LTE systems, the next generation mobile communication system may have a bandwidth equal to or greater than the maximum bandwidth of the existing system, may adopt orthogonal frequency division multiplexing (hereinafter referred to as "OFDM") as a wireless access technology, and may also adopt beamforming technology in addition to this. In addition, one system may support all multiple subcarrier spacings (SCS). Control signals and data signals may also have different SCSs.

[0095] In a new radio (NR) system, the downlink transmission bandwidth and the uplink transmission bandwidth may be different from each other in a frequency division duplex (FDD) system in which the downlink and uplink operate separately by frequency. The channel bandwidth represents the RF bandwidth corresponding to the system transmission bandwidth. Tables 1-01 and 1-02 show some relationships between the system transmission bandwidth, subcarrier spacing, and channel bandwidth defined in the NR system in frequency bands below 6 GHz and above 6 GHz, respectively. For example, the transmission bandwidth of an NR system with a 100 MHz channel bandwidth and a 30 kHz subcarrier spacing includes 273 RBs. In the following, N / A may be a combination of bandwidth and subcarriers that are not supported by the NR system.

[0096] Table 1-01

[0097]

[0098] Table 1-02

[0099]

[0100] In addition, an adaptive modulation and coding (AMC) scheme is applied in which the modulation scheme and the channel coding rate are determined according to the channel state of the terminal. In addition, a method for managing multiple bandwidth parts by a single system is used. The base station can configure one or more bandwidth parts for the terminal, and the following information can be configured for each bandwidth part.

[0101] For example, the base station may configure the information shown in Table 2 for the terminal.

[0102] Table 2

[0103]

[0104] In addition to the configuration information, various parameters associated with the bandwidth part may be configured in the terminal. The information may be sent by the base station to the terminal via high-layer signaling {e.g., radio resource control (RRC) signaling}. At least one configured bandwidth part may be activated. Information on whether to activate the configured bandwidth part may be semi-statically sent from the base station to the terminal via RRC signaling, or may be dynamically sent from the base station to the terminal via downlink control information (DCI).

[0105] Before the RRC connection, the terminal can receive the configuration of the initial bandwidth part (BWP) for initial access from the base station through the master information block (MIB). More specifically, the terminal can receive configuration information about the control resource set (CORESET) and the search space, through which the physical layer downlink control channel (PDCCH) for receiving the system information required for initial access through the MIB in the initial access phase {remaining system information, which may correspond to the remaining minimum system information (RMSI) or system information block 1 (SIB1)} can be sent. The control resource set and search space configured using the MIB can be regarded as identifiers (ID) "0" respectively. The base station can notify the terminal of the configuration information for control resource set #0, such as frequency allocation information, time allocation information, parameter sets, etc. through the MIB.

[0106] In addition, the base station may notify the terminal of the configuration information about the monitoring period and timing of the control resource set #0 (i.e., the configuration information about the search space #0) through the MIB. The terminal may regard the frequency domain configured with the control resource set #0 obtained from the MIB as the initial bandwidth part for initial access. At this time, the identifier (ID) of the initial bandwidth part may be regarded as 0.

[0107] Configuration of bandwidth portions supported by the fifth generation (5G) can be used for various purposes.

[0108] For example, in the case where the bandwidth supported by the terminal is less than the system bandwidth, this can be supported by configuring the bandwidth part. For example, the frequency position of the bandwidth part can be configured in the terminal so that the terminal can send and receive data at a specific frequency position within the system bandwidth.

[0109] As another example, for the purpose of supporting different parameter sets, the base station may configure multiple bandwidth parts for the terminal. For example, in order to support the terminal to send and receive data using a subcarrier spacing of 15kHz and a subcarrier spacing of 30kHz, two bandwidth parts may be configured as a subcarrier spacing of 15kHz and a subcarrier spacing of 30kHz, respectively. Different bandwidth parts may be frequency-division multiplexed, and in the case of sending and receiving data with a specific subcarrier spacing, the bandwidth part configured in the corresponding subcarrier spacing may be activated.

[0110] As another example, in order to reduce the power consumption of the terminal, the base station can configure bandwidth parts with different bandwidths for the terminal. For example, if the terminal supports a very large bandwidth (e.g., 100MHz bandwidth) and always sends and receives data through the corresponding bandwidth, this may cause very large power consumption. In particular, in the absence of business, monitoring unnecessary downlink control channels with a large bandwidth of 100MHz is very inefficient in terms of power consumption. In order to reduce the power consumption of the terminal, the base station can configure a bandwidth part with a relatively small bandwidth (e.g., a 20MHz bandwidth part) for the terminal. In the absence of business, the terminal can perform monitoring operations through the 20MHz bandwidth part, and, if data is generated, the terminal can send and receive data through the 100MHz bandwidth part according to the instruction of the base station.

[0111] In the method for configuring the bandwidth part, a terminal that has not yet been RRC connected can receive configuration information about the initial bandwidth part through a master information block (MIB) and / or SIB in the initial access phase. More specifically, the terminal can be configured to have a control resource set (CORESET) for a downlink control channel, wherein the downlink control information (DCI) for scheduling the system information block (SIB) is sent from the MIB of the physical broadcast channel (PBCH) through the downlink control channel. The bandwidth of the control resource set configured by the MIB can be regarded as the initial bandwidth part, and the terminal can receive the PDSCH, wherein the SIB is sent through the PDSCH through the configured initial bandwidth part. The initial bandwidth part can be used for other system information (OSI), paging and random access, and receiving SIB. If the SIB received based on the MIB includes configuration information about the initial bandwidth part, the initial bandwidth part can be configured based on the SIB.

[0112] NR CN 1c-05 performs functions such as mobility support, bearer configuration, and quality of service (QoS) configuration. NR CN1c-05 is a device that performs various control functions and mobility management functions of the terminal, and is connected to multiple base stations. In addition, the next-generation mobile communication system can interoperate with the existing LTE system, and NR CN 1c-05 is connected to MME 1c-25 through a network interface. MME 1c-25 is connected to eNB 1c-30, which is an existing base station.

[0113] Figure 4 is a diagram showing a radio protocol structure of a next generation mobile communication system according to an embodiment of the present disclosure.

[0114] refer to Figure 4The radio protocols of the next generation mobile communication system include NR SDAP1d-01 or 1d-45, NR PDCP 1d-05 or 1d-40, NR RLC 1d-10 or 1d-35 and NR MAC 1d-15 or 1d-30 in the terminal and NR base station respectively.

[0115] The main functions of NR Service Data Adaptation Protocol (SDAP) 1d-01 or 1d-45 may include some of the following functions.

[0116] - User plane data delivery

[0117] - Mapping between QoS flows and Data Radio Bearers (DRBs) for downlink and uplink

[0118] - Marking of QoS flow ID in downlink and uplink packets

[0119] - Map the reflective QoS flow of ULSDAP PDU to DRB

[0120] Regarding the SDAP layer entity, the terminal may receive a configuration through an RRC message indicating whether to use the header of the SDAP layer entity, or whether to use the function of the SDAP layer entity for each PDCP layer entity, for each bearer, or for each logical channel. In the case of configuring the SDAP header, the 1-bit non-access stratum (NAS) reflection QoS configuration indicator and the 1-bit AS reflection QoS configuration indicator of the SDAP header may indicate that the terminal updates or reconfigures the mapping information between the QoS flow and the data bearer in the uplink and downlink. The SDAP header may include QoS flow ID information indicating QoS. QoS information can be used as data processing priority, scheduling information, etc. to support effective services.

[0121] The main functions of NR PDCP 1d-05 or 1d-40 may include some of the following functions.

[0122] -Header compression and decompression (ROHC only)

[0123] -Transfer of user data

[0124] - Sequential delivery of upper layer PDUs

[0125] - Out-of-order delivery of upper layer PDUs

[0126] -Sequence reordering (for received PDCP PDU reordering)

[0127] - Duplicate detection of lower layer SDU

[0128] -Retransmission of PDCP SDU

[0129] -Encryption and decryption

[0130] - Timer-based SDU discard in uplink

[0131] The above-mentioned reordering function of the NR PDCP entity represents a function of reordering the PDCP PDU received from the lower layer based on the PDCP sequence number (SN), which may include a function of sending data to the upper layer in a reordered order, a function of sending data directly to the upper layer regardless of the order, a function of reordering the sequence and recording the lost PDCP PDU, a function of sending a status report of the lost PDCP PDU to the transmitting end, and a function of requesting retransmission of the lost PDCP PDU.

[0132] The main functions of NR RLC 1d-10 or 1d-35 may include some of the following functions.

[0133] -Data transfer function (transfer of upper layer PDU)

[0134] - Sequential delivery of upper layer PDUs

[0135] - Out-of-order delivery of upper layer PDUs

[0136] -ARQ function (error correction through ARQ)

[0137] - RLC SDU splicing, segmentation and reassembly

[0138] - Re-segmentation of RLC data PDUs

[0139] - Reordering of RLC data PDUs

[0140] - Duplicate detection

[0141] -Protocol error detection

[0142] -RLC·SDU discard

[0143] -RLC reconstruction

[0144] The above-mentioned sequential delivery function of the NR RLC entity means a function of delivering the RLC SDU received from the lower layer to the higher layer in sequence, which may include a function of reassembling and sending an original RLC SDU if it is divided into multiple RLC SDUs and received, which may include a function of reordering the received RLC SDU based on the RLC sequence number (SN) or the PDCP sequence number (SN), which may include a function of reordering the sequence and recording the lost RLC PDU, which may include a function of sending a status report of the lost RLC PDU to the transmitting end, which may include a function of requesting retransmission of the lost RLC PDU, which may include a function of sending only the RLC SDU before the lost RLC SDU in sequence to the upper layer if there is a lost RLC SDU, which may include a function of sending all RLC SDUs received before the start of the timer in sequence to the upper layer even if there is a lost RLC SDU if a predetermined timer expires, or which may include a function of sending all RLC SDUs received until now in sequence to the upper layer if a predetermined timer expires even if there is a lost RLC SDU. In addition, the RLC PDU can be processed in the order of reception (in the order of arrival, regardless of its sequence number or sequence number) and can be sent to the PDCP entity in an out-of-order delivery manner. In the case of segmentation, segments stored in the buffer or to be received later can be received and reconfigured into a complete RLC PDU, and the RLC PDU can be processed and sent to the PDCP entity. The NR RLC layer may not include a splicing function, which may be performed in the NR MAC layer, or may be replaced by a multiplexing function of the NR MAC layer.

[0145] Out-of-order delivery of the NR RLC entity means a function of delivering the RLC SDU received from the lower layer directly to the higher layer without considering the order, which may include the function of reassembling and delivering the original RLC SDU if it is divided into multiple RLC SDUs and received, and may include the function of storing and sorting the RLC SN or PDCP SN of the received RLC SDU, thereby recording the lost RLC PDU.

[0146] NR MAC 1d-15 or 1d-30 can be connected to multiple NR RLC entities configured in a single terminal, and the main functions of NR MAC may include some of the following functions.

[0147] - Mapping between logical channels and transport channels

[0148] -Multiplexing / demultiplexing of MAC SDU

[0149] -Dispatch information report

[0150] -HARQ function (error correction through HARQ)

[0151] - Priority handling between logical channels of a UE

[0152] - Priority handling between UEs through dynamic scheduling

[0153] -MBMS service logo

[0154] -Transmission format selection

[0155] -filling

[0156] The NR PHY layers 1d-20 and 1d-25 may perform operations of channel encoding and modulating upper layer data into OFDM symbols and sending them through a radio channel, or of demodulating and channel decoding OFDM symbols received through a radio channel and sending them to an upper layer.

[0157] Figure 5 2 is a diagram showing the structure of a message for reporting UE capabilities in an NR system according to an embodiment of the present disclosure.

[0158] refer to Figure 5 , the terminal 1e-01 is connected to the serving base station 1e-02, and performs a process of reporting the capabilities supported by the terminal 1e-01 to the base station 1e-02. In operation 1e-05, the base station 1e-02 sends a UE capability inquiry message requesting a capability report to the connected terminal 1e-01. The message may include a UE capability request for each radio access technology (RAT) type made by the base station. The request for each RAT type may include information about the requested frequency band.

[0159] In addition, the UE capability inquiry message may include a single RRC message container requesting multiple RAT types, or an RRC message including multiple UE capability inquiry messages including requests for each RAT type may be sent to the terminal. That is, in operation 1e-05, the UE capability inquiry may be repeated multiple times, and the terminal may configure multiple UE capability information messages corresponding thereto, and may report the UE capability information message multiple times. In the next generation communication system, UE capability requests may be performed for MR-DC as well as NR, LTE, and EN-DC. For reference, the UE capability inquiry message is typically sent during the process of the terminal establishing a DC connection or after the DC connection is established, but may also be sent under any conditions when the base station requires it.

[0160] In the above operation, the terminal that receives the request for UE capability report from the base station configures the UE capability according to the RAT type and frequency band information requested by the base station. The method for configuring UE capability by the terminal in the NR system is summarized as follows.

[0161] 1. If the terminal receives a list of LTE and / or NR bands through a request for UE capabilities from the base station, the terminal configures a band combination (BC) for EN-DC and NR stand-alone (SA). That is, the terminal configures a candidate list of BCs for EN-DC and NR SA based on the bands requested by the base station through "FreqBandList". In addition, the bands have priorities in the order described in "FreqBandList".

[0162] 2. If the "eutra-nr-only" flag or the "eutra" flag is set, the NR SA BC will be completely removed from the configured BC candidate list. This may only happen if the LTE base station (eNB) requests the "eutra" capability.

[0163] 3. Afterwards, the terminal removes the fallback BC from the BC candidate list configured in the above operation. Here, the fallback BC corresponds to the case where the frequency band corresponding to at least one SCell is removed from a superset BC and can be omitted because the superset BC can cover the fallback BC. This operation also applies to MR-DC (i.e., LTE frequency band). The remaining BCs after this operation constitute the final "candidate BC list".

[0164] 4. The terminal selects the BC to be reported by selecting the BC that meets the requested RAT type from the final "candidate BC list" above. In this operation, the terminal configures the "supportedBandCombinationList" in a predetermined order. That is, the terminal configures the BC to be reported and the UE capabilities in the order of the predetermined RAT type (nr->eutra-nr->eutra). In addition, the terminal configures the "featureSetCombination" for the configured "supportedBandCombinationList" and configures the "candidate feature set combination" list from the candidate BC list, from which the fallback BC list (including capabilities of equal or lower levels) is removed. The "candidate feature set combination" may include a feature set combination of both NR and EUTRA-NR BCs, and may be obtained from the feature set combinations of the UE-NR-capabilities and UE-MRDC-capabilities containers.

[0165] 5. In addition, if the requested RAT type is "eutra-nr" and has an impact, "featureSetCombinations" is included in both "UE-MRDC-capabilities" and "UE-NR-capabilities" containers. However, the feature set of NR is only included in "UE-NR-capabilities".

[0166] After configuring the UE capabilities, in operation 1e-10, the terminal 1e-01 sends a UE capability information message including the UE capabilities to the base station. Then, the base station 1e-02 performs appropriate scheduling and transmission / reception management for the corresponding terminal based on the UE capabilities received from the terminal 1e-01.

[0167] The present disclosure provides a method for configuring and reporting UE capabilities based on the case where a base station uses "UECapabilityEnquiry" including "UE-CapabilityRAT-Request" as described above to request reporting UE capabilities, and further considering the case where a terminal sends temporarily changed UE capabilities to a base station. The operation method may vary according to various embodiments of the present disclosure, and the present disclosure and the following embodiments propose a method for supporting general UE capability restriction (temporary capability restriction) and specific application examples thereof.

[0168] Temporary changes in UE capabilities may occur due to the following issues.

[0169] 1. Sharing hardware in the terminal with other communication methods other than NR (wireless local area network (WLAN), Bluetooth, global positioning system (GPS), etc.)

[0170] 2. Interference between NR and other communication methods (WLAN, Bluetooth, GPS, etc.)

[0171] 3. Abnormal operation of the terminal (overheating, power saving mode, power consumption issues, etc.)

[0172] 4. Change of terminal mode {Selectively determined from the dual modes. For example, in the case of a foldable terminal, the performance of the terminal may be configured differently between its folded state and unfolded state. Depending on the mode of the terminal, the performance of the terminal may be different in hardware (such as antenna performance, support or non-support of MIMO, etc.), or the terminal may be intentionally configured to have different UE capabilities.}

[0173] Figure 6 2 is a diagram illustrating a method in which a terminal in an RRC connected state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0174] refer to Figure 6Specifically, after the terminal requests temporary UE capability restriction, the base station stores the request without acceptance / rejection of the base station and reflects the request through RRC reconfiguration.

[0175] In order to connect to the base station 1f-02, the terminal 1f-01 performs an RRC connection process including random access, thereby switching to an RRC connected state (1f-05). In operation 1f-05, the terminal 1f-01 in the RRC connected state receives a request to report UE capabilities from the base station 1f-02. In this operation, "UECapabilityEnquiry" can be used to send multiple "UE-CapabilityRAT-Requests", or a request for a report of one RAT type can be sent. If "UECapabilityEnquiry" is used to send multiple "UE-CapabilityRAT-Requests" in the above operation, the terminal 1f-01 configures the UE capabilities based on the priority requested according to the RAT type. For example, the terminal 1f-01 configures the UE capability container in LTE according to the following priority.

[0176] ue-CapabilityRAT-Container for nr

[0177] ue-CapabilityRAT-Container for eutra-nr

[0178] ue-CapabilityRAT-Container for eutra

[0179] If the content of MR-DC is determined, the report of another RAT type has a priority value and the terminal 1f-01 must report according to the priority value.

[0180] In operation 1f-15, the terminal 1f-01 sends a "UECapabilityInformation" message to the base station 1f-02, including UE capability information configured according to the priority in its container. This message is sent to the base station 1f-02 via an RRC message and includes static UE capabilities such as RAT type, frequency band information, etc. requested by the base station 1f-02. Although the terminal 1f-01 can adjust the implementation of UE capabilities for the requested RAT type and frequency band information and report the implementation, in this operation, the terminal 1f-01 basically sends static information about the terminal. This is because in the event that a temporary capability restriction request reported later expires, it is necessary to return to the information required for the previous static UE capabilities.

[0181] In operation 1f-20, base station 1f-02 sends the UE capability information received from terminal 1f-01 to 5G CN 1f-03, and 5G CN 1f-03 stores the received static UE capability information. The UE capability information stored in 5G CN 1f-03 in the above operation can be maintained until the RRC connection of terminal 1f-01 is released, and can be used for service configuration and mobility management of terminal 1f-01.

[0182] In the present disclosure, UE capabilities are statically sent to base station 1f-02 and 5G CN 1f-03, and if there is no separate signaling, the inherent capabilities of terminal 1f-01 remain unchanged. However, in the case of an actual terminal 1f-01, due to the above four reasons and other reasons, it may be necessary to temporarily change the UE capabilities. That is, due to sharing hardware with other communication modules in the terminal 1f-01, interference with them, temporary heating, changes in terminal mode, etc., a temporary change in UE capabilities that is different from the static terminal performance may be generated / needed. Generally, in the event that the UE capabilities are temporarily reduced compared to the static UE capabilities, the terminal 1f-01 needs to report the situation to the base station 1f-02 to request scheduling and management that complies with the reduced UE capabilities.

[0183] For example, in the case of a foldable terminal, if the performance of the terminal is the static UE capability when the display is unfolded, the performance of the terminal in the state where the display is folded can be configured to be lower. That is, the change in the state of the terminal can make a difference in the performance of the antenna and MIMO applied to the terminal, the power performance of the terminal, etc. In order to support the above situation, in addition to the existing method of reporting UE capabilities, a new signaling structure and its functions are required.

[0184] In an embodiment of the present disclosure, in certain circumstances, a terminal may have a higher UE capability than the static UE capability that the terminal has reported. For example, in the case of a foldable terminal, if the performance of the terminal is the static UE capability when the display is folded, the performance of the terminal when the display is unfolded may be configured to be higher. That is, a change in the state of the terminal may produce differences in the performance of the antenna and MIMO applied to the terminal, the power performance of the terminal, and so on. In order to support the above situation, in addition to the existing method of reporting UE capabilities, a new signaling structure and its functions are also required.

[0185] An embodiment proposes a method in which a terminal in a connected state requests a temporary capability restriction through an RRC message. If the conditions required for the temporary change of UE capabilities are internally met in operation 1f-25, the terminal 1f-01 can trigger the condition. In operation 1f-30, the terminal 1f-01 requests a temporary capability restriction through an RRC message (such as UE auxiliary information). The RRC message may include at least one piece of information that the terminal can request, such as the reason for requesting a temporary UE capability change (for example, reason value: hardware sharing, interference, overheating, mode change, battery problem, etc.), frequency bands and frequency band combination information to be supported, changes in the physical functions of the terminal (changes in the number of component carriers, changes in the number of MIMO layers, changes in the frequency bands and bandwidth information to be supported by each CC, changes in supported power, changes in the frequency range to be supported, etc.), etc. The detailed items included in the RRC message and its signaling method will be described in more detail later in another embodiment.

[0186] When a terminal reports a change in UE capabilities, if only UE capabilities with a temporary change less than the static UE capabilities are reported, only a subset of the static UE capabilities may always be reported. That is, this is a request to temporarily have some reduced capabilities of the overall static UE capabilities. However, if UE capabilities with a temporary change higher than the static UE capabilities may be reported, then new UE capabilities higher than those reported in the previous static report must be signaled.

[0187] In addition, a prohibition timer 1f-35 for prohibiting requests to change UE capabilities can be configured to prevent the terminal 1f-01 from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time. If the prohibition timer is not configured, the terminal 1f-01 may frequently send UE capability reports, which makes it difficult for the base station 1f-02 to perform scheduling and management of the terminal 1f-01. The prohibition timer 1f-35 can be configured to be included in msg 4 during the RRC connection process, and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1f-35 can be configured as a default value according to the internal settings of the terminal, or can be obtained from system information.

[0188] In operation 1f-40, the base station 1f-02 stores the temporary capability restriction information received from the terminal 1f-01 and determines whether to reflect the information. In this case, the received information is managed only in the access layer (AS) area instead of sending it to the 5G CN. In an embodiment of the present disclosure, the base station 1f-02 does not send a separate confirmation / rejection message after receiving an RRC message including a temporary capability restriction from the terminal 1f-01. If the base station 1f-02 is to reflect the temporary capability restriction from the terminal 1f-01, the base station 1f-02 can reflect the temporary capability restriction, thereby sending new RRC configuration information to the terminal 1f-01 through an RRC reconfiguration message in operation 1f-45. Alternatively, even in the state of receiving a temporary capability restriction from the terminal 1f-01, the base station 1f-02 can omit operation 1f-45 without reflecting the temporary capability restriction. That is, the base station 1f-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capability received in the previous operation 1f-10. The terminal 1f-01 that receives the RRC reconfiguration from the base station 1f-02 in operation 1f-45 sends information indicating that the RRC reconfiguration has been received to the base station 1f-02 via an RRC reconfiguration completion message for the configuration (operation 1f-50).

[0189] If the terminal 1f-01 needs to release the temporary change of UE capabilities in a state where the temporarily changed UE capabilities are reflected through the above-mentioned process of temporarily changing UE capabilities and the RRC reconfiguration according to the process (operation 1f-55), then in operation 1f-60, the terminal 1f-01 notifies the base station 1f-02 through a temporary capability restriction release message that the temporary change of UE capabilities has been completed and the terminal has returned to the original static UE capabilities. Upon receiving the RRC message, the base station 1f-02 may send a release response RRC message to the terminal 1f-01 in operation 1f-65 indicating that the corresponding release message has been received. In operation 1f-70, the base station 1f-02 may determine that the terminal 1f-01 has returned to the static UE capabilities, and may then send a new RRC reconfiguration message. Alternatively, the release response message in operation 1f-65 may be omitted. That is, if a temporary capability restriction release message is received in operation 1f-60, the base station 1f-02 may send a new RRC reconfiguration message to the terminal 1f-01 without responding to it.

[0190] In addition to the case where the terminal 1f-01 explicitly requests to release the temporary UE capability change as described above, the base station 1f-02 can identify the temporary capability change of the terminal in the following cases. The following conditions can be applied to the terminal 1f-01 at the same time.

[0191] 1. When the terminal explicitly requests to release the temporary restriction

[0192] 2. The terminal previously indicated a request for a new temporary restriction

[0193] 3. The terminal switches to the RRC idle state or the RRC inactive state. The terminal may switch to the RRC idle state or the RRC inactive state based on a timer, at the request of the base station, or at the request of the terminal.

[0194] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0195] Figure 7 2 is a diagram illustrating a method in which a terminal in an RRC connected state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0196] refer to Figure 7 Specifically, after requesting temporary UE capability restriction, the terminal receives an acceptance / rejection message from the base station, thereby determining whether to apply the request for temporary UE capability change of the terminal.

[0197] In order to connect to the base station 1g-02, the terminal 1g-01 performs an RRC connection process including random access, thereby switching to an RRC connected state (1g-05). In operation 1g-05, the terminal 1g-01 in the RRC connected state receives a request to report UE capabilities from the base station 1g-02. In the above operation, "UECapabilityEnquiry" can be used to send multiple "UE-CapabilityRAT-Requests", or a request for a report of one RAT type can be sent. If "UECapabilityEnquiry" is used to send multiple "UE-CapabilityRAT-Requests" in the above operation, the terminal 1g-01 configures the UE capabilities based on the priority requested according to the RAT type. For example, the terminal 1g-01 configures the UE capability container in LTE according to the following priority.

[0198] -ue-CapabilityRAT-Container for nr

[0199] -ue-CapabilityRAT-Container for eutra-nr

[0200] -ue-CapabilityRAT-Container for eutra

[0201] If the content of MR-DC is determined, the report of another RAT type has a priority value and the terminal 1g-01 must report according to the priority value.

[0202] In operation 1g-15, the terminal 1g-01 sends a "UECapabilityInformation" message including UE capability information configured according to the priority in its container to the base station 1g-02. The message is sent to the base station 1g-02 via an RRC message and includes static UE capabilities such as RAT type, frequency band information, etc. requested from the base station 1g-02. Although the terminal 1g-01 can adjust the implementation of UE capabilities for the requested RAT type and frequency band information and report the implementation, in this operation, the terminal 1g-01 basically sends static information about the terminal. This is because in the event that a temporary capability restriction request reported later expires, it is necessary to return to the information required for the previous static UE capabilities.

[0203] In operation 1g-20, the base station 1g-02 sends the UE capability information received from the terminal 1g-01 to the 5G CN 1g-03, and the 5G CN 1g-03 stores the received static UE capability information. The UE capability information stored in the 5G CN 1g-03 in the above operation can be maintained until the RRC connection of the terminal 1g-01 is released, and can be used for service configuration and mobility management of the terminal 1g-01.

[0204] In an embodiment of the present disclosure, UE capabilities are statically sent to base station 1g-02 and 5G CN 1g-03, and if there is no separate signaling, the inherent capabilities of terminal 1g-01 remain unchanged. However, in the case of an actual terminal 1g-01, due to the above four reasons and other reasons, it may be necessary to temporarily change the UE capabilities. That is, due to sharing hardware with other communication modules in the terminal 1g-01, interference with them, temporary heating, changes in terminal mode, etc., a temporary change in UE capabilities that is different from the static terminal performance may be generated / needed. Generally, in the event that the UE capabilities are temporarily reduced compared to the static UE capabilities, the terminal 1g-01 needs to report the situation to the base station 1g-02 to request scheduling and management that complies with the reduced UE capabilities. However, in certain cases, the terminal 1g-01 may have a higher UE capability than the static UE capabilities that the terminal 1g-01 has reported.

[0205] For example, in the case of a foldable terminal, if the performance of the terminal is the static UE capability when the display is folded, the performance of the terminal in the state where the display is unfolded can be configured to be higher. That is, the change in the state of the terminal can make a difference in the performance of the antenna and MIMO applied to the terminal, the power performance of the terminal, etc. In order to support the above situation, in addition to the existing method of reporting UE capabilities, a new signaling structure and its functions are required.

[0206] An embodiment proposes a method in which a terminal in a connected state requests a temporary capability restriction through an RRC message. If the conditions required for the temporary change of UE capabilities are met internally in operation 1g-25, the terminal 1g-01 can trigger the condition. In operation 1g-30, the terminal 1g-01 requests a temporary capability restriction through an RRC message (such as UE auxiliary information). The RRC message may include at least one piece of information that the terminal can request, such as the reason for requesting a temporary change in UE capabilities (for example, a reason value: hardware sharing, interference with them, overheating, mode change, etc.), frequency bands and frequency band combination information to be supported, changes in the physical functions of the terminal (changes in the number of component carriers, changes in the number of MIMO layers, changes in the frequency bands and bandwidth information to be supported by each CC, changes in supported power, changes in the frequency range to be supported, etc.), etc. The detailed items included in the RRC message and their signaling methods will be described in more detail in another embodiment below.

[0207] When a terminal reports a change in UE capabilities, if only UE capabilities with a temporary change less than the static UE capabilities are reported, only a subset of the static UE capabilities may always be reported. That is, this is a request to temporarily have some reduced capabilities of the overall static UE capabilities. However, if UE capabilities with a temporary change higher than the static UE capabilities may be reported, then new UE capabilities higher than those reported in the previous static report must be signaled.

[0208] In addition, a prohibition timer 1g-35 for prohibiting requests to change UE capabilities can be configured to prevent the terminal from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time. If the prohibition timer is not configured, the terminal 1g-01 may frequently send UE capability reports, which makes it difficult for the base station 1g-02 to perform scheduling and management of the terminal 1g-01. The prohibition timer 1g-35 can be configured to be included in msg 4 during the RRC connection process, and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1g-35 can be configured as a default value according to the internal settings of the terminal, or can be obtained from system information.

[0209] Thereafter, the base station 1g-02 may send a temporary capability restriction confirmation / rejection message in response to the temporary capability restriction request message. If the base station 1g-02 accepts the temporary capability restriction request from the terminal 1g-01, the base station 1g-02 sends a confirmation message, and if the base station 1g-02 rejects the temporary capability restriction request, the base station 1g-02 sends a rejection message. Both messages may be sent using RRC messages.

[0210] In operation 1g-45, the base station 1g-02 stores or does not reflect the temporary capability limitation information received from the terminal 1g-01 according to whether the temporary capability limitation determined in the operation is reflected. The base station 1g-02 manages the received information only in the access layer (AS) area without sending it to the 5G CN 1g-03. According to an embodiment of the present disclosure, after receiving an RRC message including a temporary capability limitation from the terminal 1g-01, a separate confirmation / rejection message is sent.

[0211] In operation 1g-50, base station 1g-02 can reflect the temporary capability limitation, thereby sending new RRC configuration information to terminal 1g-01 through an RRC reconfiguration message. However, if base station 1g-02 rejects the temporary capability limitation request from terminal 1g-01 (if base station 1g-02 sends a rejection message in operation 1g-40), base station 1g-02 can omit operation 1g-50 without reflecting the temporary capability limitation. That is, base station 1g-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capabilities received in the previous operation 1g-10. Terminal 1g-01, which receives the RRC reconfiguration from base station 1g-02 in operation 1g-50, sends information indicating that the RRC reconfiguration has been received to base station 1g-02 through an RRC reconfiguration completion message for the configuration (operation 1g-55).

[0212] If the terminal 1g-01 needs to release the temporary change of UE capabilities in a state where the temporarily changed UE capabilities are reflected through the above-mentioned process of temporarily changing UE capabilities and the RRC reconfiguration according to the process (operation 1g-60), then in operation 1g-65, the terminal 1g-01 notifies the base station 1g-02 through a temporary capability restriction release message that the temporary change of UE capabilities has been completed and the terminal has returned to the original static UE capabilities. Upon receiving the RRC message, the base station 1g-02 can send a release response RRC message indicating that the corresponding release message has been received to the terminal 1g-01 in operation 1g-70.

[0213] In operation 1g-75, the base station 1g-02 may determine that the terminal 1g-01 has returned to the static UE capability, and may then send a new RRC reconfiguration message to the terminal 1g-01. Alternatively, the release response message in operation 1g-70 may be omitted. That is, if the base station 1g-02 receives the temporary capability restriction release message in operation 1g-65, the base station 1g-02 may send a new RRC reconfiguration message to the terminal 1g-01 without responding to it.

[0214] In addition to the case where the terminal 1g-01 explicitly requests to release the temporary UE capability change as described above, the base station 1g-02 can recognize the temporary capability change of the terminal in the following cases. The following conditions can be applied to the terminal 1g-01 at the same time.

[0215] 1. When the terminal explicitly requests to release the temporary restriction

[0216] 2. The terminal previously indicated a request for a new temporary restriction

[0217] 3. The terminal switches to the RRC idle state or the RRC inactive state.

[0218] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0219] Figure 8 is a diagram illustrating a method in which a terminal in an RRC idle state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0220] refer to Figure 8 Specifically, after the terminal requests temporary UE capability restriction in an operation of requesting to switch from an idle state to a connected state, if the terminal enters an RRC connected state, the terminal requests content of the temporary UE capability restriction.

[0221] In operation 1h-05, the terminal 1h-01 in the RRC idle state may have a temporary change in UE capabilities. Generally, when the terminal is in a connected state, the UE capabilities may change due to sharing hardware with other communication technologies, interference with them, heat generation, etc. However, even in the idle state, the UE capabilities of the terminal may be affected by the use of other communication technologies (such as WLAN, Bluetooth, etc.), so this needs to be taken into account and managed from the initial RRC connection state.

[0222] In an embodiment of the present disclosure, even if the UE capability temporarily changes in the idle state, there is no need to trigger the RRC connection process. Even if the changed UE capability is not reported in a state other than the RRC connection state, it does not affect the configuration of the base station. Therefore, the RRC connection process may be triggered only when a general RRC connection is required (when uplink / downlink data occurs). That is, although the temporary change of UE capability does not trigger the RRC connection process, if the RRC connection process is triggered due to another reason, it is necessary to determine whether the terminal currently requires a temporary change in UE capability, and if a capability change is necessary, the subsequent process reflects this situation.

[0223] In an embodiment of the present disclosure, in order to notify the base station in advance that the UE capability has been temporarily changed in the idle state, the RRC connection process may be triggered even when the RRC connection is not required.

[0224] Generally, if there is a static UE capability that the terminal reports to the base station in the corresponding operation in the previous RRC connection state, the base station can receive the UE capability from the CN (UE capability retrieval condition 1), in which case the base station may not request the UE capability of the terminal after the RRC connection process. However, if the base station fails to retrieve the static UE capability of the terminal (UE capability retrieval condition 2), the base station may request and receive the UE capability of the terminal after the RRC connection process. Depending on the above conditions, the operations of the base station and the terminal may be different.

[0225] In operation 1h-10, terminal 1h-01 triggers random access to base station 1h-02. That is, terminal 1h-01 sends a random access preamble (msg 1) to base station 1h-02 and starts the RRC connection process. In an embodiment of the present disclosure, a random access preamble (msg 1) can be used to notify temporary capability restrictions. At least one of a predefined preamble ID, time resources, and frequency resources can be used. Alternatively, the random access preamble (msg 1) may include an indicator indicating a temporary capability restriction. In operation 1h-15, terminal 1h-01 receives a random access response (msg 2) from base station 1h-02 and synchronizes the uplink. Thereafter, in operation 1h-20, terminal 1h-01 may include an indicator indicating a temporary capability restriction in an RRC connection establishment request message (msg 3). By including an indicator indicating the presence of a UE capability change in this operation, the base station can pre-identify that terminal 1h-01 will request a temporary capability restriction later.

[0226] In the above operation, msg 3 does not include the details of the temporary capability restriction because msg 3 is size-sensitive and cannot contain a large amount of information. For example, msg 3 may be a message such as an RRC establishment request, an RRC recovery request, an RRC reconstruction request, and the like. In the LTE system, a 56-bit msg 3 is used, and the minimum uplink grant size in NR is also 56 bits. For reference, msg 3 must have good link performance within the cell coverage because it is a request message trying to connect to the network. In addition, since the size of the packet sent by terminal 1h-01 is small, the terminal coverage is expanded. Therefore, in the case of allocating 56 bits or more of uplink grants, the performance of the cell access coverage may deteriorate. As a result, in the NR system, a separate logical channel identifier (LCID) is further allocated to the MAC header to distinguish between a 56-bit uplink grant for common control channel (CCCH) transmission and an uplink grant of 56 bits or more (e.g., 72 bits). However, in the case where a 56-bit uplink grant is allocated, since msg 3 cannot carry and send all of the 5G-S-TMSI which has an increase of 8 bits compared to the SAE-Temporary Mobile Subscriber Identity (S-TMSI) in LTE, msg 3 must send a portion of the 5G-S-TMSI and msg 5 must send the rest thereof.

[0227] In operation 1h-25, the base station 1h-02 sends an RRC connection establishment message (msg 4) to the terminal 1h-01 in response to the received RRC connection establishment request message. The message may include a radio bearer configuration and a master cell group (MCG) configuration (RLC bearer, "mac-CellGroupConfig", "physicalCellGroupConfig and spCellConfig", etc.) for signaling radio bearer (SRB) 1. The message includes a general configuration of the base station 1h-02 for SRB 1 in this operation, and the terminal 1h-01 receives msg 4 and sends an RRC connection establishment completion message (msg 5) in response to the configuration of SRB 1 in operation 1h-30.

[0228] The message may include the selected public land mobile network (PLMN) ID, the registered access and mobility management function (AMF), the globally unique AMF ID (GUAMI) type, the single network slice selection assistance information (S-NSSAI) list, the NAS message, etc. Based on the content of msg 5 sent from the terminal 1h-01, the base station 1h-02 can retrieve the static capabilities and context of the terminal from the CN, and if there is no corresponding UE capability or if the base station 1h-02 fails to retrieve the UE capability, the base station 1h-02 can request a report on the UE capability. That is, if the above UE capability retrieval condition 1 is met, operations 1h-35, 1h-40 and 1h-45 can be omitted, and operations 1h-35, 1h-40 and 1h-45 can be performed only when the UE capability retrieval condition 2 is met.

[0229] In operation 1h-35, the terminal 1h-01 may receive a request to report UE capabilities from the base station 1h-02 via an RRC message, and may use the "UECapabilityEnquiry" in the message to send multiple "UE-CapabilityRAT-Requests", or may send a request for a report on one RAT type. If "UECapabilityEnquiry" is used to send multiple "UE-CapabilityRAT-Requests" in the above operation, the terminal 1h-01 configures the UE capabilities based on the priority requested according to the RAT type. The request may include frequency band information, restrictions on report content, etc. For example, the terminal 1h-01 configures the UE capability container in LTE according to the following priority.

[0230] -ue-CapabilityRAT-Container for nr

[0231] -ue-CapabilityRAT-Container for eutra-nr

[0232] -ue-CapabilityRAT-Container for eutra

[0233] If the content of MR-DC is determined, the report of another RAT type has a priority value and the terminal 1h-01 must report according to the priority value.

[0234] In operation 1h-40, the terminal 1h-01 sends a "UECapabilityInformation" message to the base station 1h-02, including UE capability information configured according to the priority in its container. The message is sent to the base station 1h-02 via an RRC message and includes static UE capabilities such as RAT type, frequency band information, etc. requested from the base station 1h-02. Although the terminal 1h-01 can adjust the implementation of UE capabilities for the requested RAT type and frequency band information and report the implementation, in this operation, the terminal 1h-01 basically sends static information about the terminal. This is because in the event that a temporary capability restriction request reported later expires, it is necessary to return to the information required for the previous static UE capabilities.

[0235] In operation 1h-45, the base station 1h-02 sends the UE capability information received from the terminal 1h-01 to the 5G CN 1h-03, and the 5G CN 1h-03 stores the received static UE capability information. The UE capability information stored in the 5G CN 1h-03 in the above operation can be maintained until the RRC connection of the terminal 1h-01 is released, and can be used for service configuration and mobility management of the terminal 1h-01.

[0236] Fundamentally, UE capabilities are statically sent to base station 1h-02 and 5G CN 1h-03, and if there is no separate signaling, the inherent capabilities of terminal 1h-01 remain unchanged. However, in the case of an actual terminal 1h-01, due to the above four reasons and other reasons, it may be necessary to temporarily change the UE capabilities. That is, due to sharing hardware with other communication modules in the terminal, interference with them, temporary heating, changes in terminal mode, etc., a temporary change in UE capabilities that is different from the static terminal performance may be generated / needed. Generally, in the event that the UE capabilities are temporarily reduced compared to the static UE capabilities, the terminal needs to report the situation to the base station 1h-02 to request scheduling and management that complies with the reduced UE capabilities. However, in certain circumstances, the terminal may have a higher UE capability than the static UE capabilities that the terminal has reported.

[0237] For example, in the case of a foldable terminal, if the performance of the terminal is the static UE capability when the display is folded, the performance of the terminal in the state where the display is unfolded can be configured to be higher. That is, the change in the state of the terminal can make a difference in the performance of the antenna and MIMO applied to the terminal, the power performance of the terminal, etc. In order to support the above situation, in addition to the existing method of reporting UE capabilities, a new signaling structure and its functions are required.

[0238] An embodiment proposes a method in which a terminal in a connected state requests a temporary capability restriction through an RRC message. In operation 1h-50, the terminal 1h-01 sends information about a temporary change in UE capability (i.e., temporary capability restriction) and a request for it through an RRC message (such as UE auxiliary information). The RRC message may include at least one piece of information that the terminal 1h-01 can request, such as the reason for requesting a temporary change in UE capability (e.g., reason value: hardware sharing, interference, overheating, mode change, etc.), frequency bands and frequency band combination information to be supported, changes in the physical functions of the terminal (changes in the number of component carriers, changes in the number of MIMO layers, changes in the frequency bands and bandwidth information to be supported by each CC, changes in supported power, changes in the frequency range to be supported, etc.), etc. The detailed items included in the RRC message and their signaling methods will be described in more detail in another embodiment below.

[0239] When a terminal reports a change in UE capabilities, if only UE capabilities with a temporary change less than the static UE capabilities are reported, only a subset of the static UE capabilities may always be reported. That is, this is a request to temporarily have some reduced capabilities of the overall static UE capabilities. However, if UE capabilities with a temporary change higher than the static UE capabilities may be reported, then new UE capabilities higher than those reported in the previous static report must be signaled.

[0240] In addition, a prohibition timer 1h-55 for prohibiting requests to change UE capabilities can be configured to prevent the terminal from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time. If the prohibition timer is not configured, the terminal 1h-01 may frequently send UE capability reports, which makes it difficult for the base station 1h-02 to perform scheduling and management of the terminal 1h-01. The prohibition timer 1h-55 can be configured to be included in msg 4 during the RRC connection process, and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1h-55 can be configured as a default value according to the internal settings of the terminal, or can be obtained from system information.

[0241] Although not shown, the base station 1h-02 can send a temporary capability restriction confirmation / rejection message to the terminal 1h-01 in response to the temporary capability restriction request message. If the base station 1h-02 accepts the temporary capability restriction request from the terminal, the base station 1h-02 sends a confirmation message, and if the base station 1h-02 rejects the temporary capability restriction request, the base station 1h-02 sends a rejection message. Both messages can be sent using RRC messages.

[0242] In operation 1h-60, the base station 1h-02 stores or does not reflect the temporary capability limitation information received from the terminal 1h-01 according to whether the temporary capability limitation determined in the operation is reflected. The base station 1h-02 manages the received information only in the access layer (AS) area, and does not send it to the 5G CN 1h-03. In operation 1h-65, the base station 1h-02 can reflect the temporary capability limitation, thereby sending new RRC configuration information to the terminal 1h-01 through an RRC reconfiguration message. However, if the base station 1h-02 rejects the temporary capability limitation request received from the terminal 1h-01, the base station 1h-02 can omit operation 1h-65 without reflecting the temporary capability limitation, or can configure the RRC configuration based on the original UE capability. That is, the base station 1h-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capability received in the previous operation. The terminal 1h-01 that has received the RRC reconfiguration from the base station 1h-02 in operation 1h-65 sends information indicating that the RRC reconfiguration has been received to the base station 1h-02 through an RRC reconfiguration complete message for the configuration (operation 1h-70).

[0243] If the terminal 1h-01 needs to release the temporary change of UE capabilities in a state where the temporarily changed UE capabilities are reflected through the above-mentioned process of temporarily changing UE capabilities and RRC reconfiguration according to the process (operation 1h-75), then in operation 1h-80, the terminal 1h-01 notifies the base station 1h-02 through a temporary capability restriction release message that the temporary change of UE capabilities has been completed and the terminal has returned to the original static UE capabilities. Upon receiving the RRC message, the base station 1h-02 can send a release response RRC message to the terminal 1h-01 in operation 1h-85 indicating that the corresponding release message has been received.

[0244] In operation 1h-90, the base station 1h-02 may determine that the terminal 1h-01 has returned to the static UE capability, and may then send a new RRC reconfiguration message to the terminal. Alternatively, the release response message in operation 1h-85 may be omitted. That is, if the base station 1h-02 receives the temporary capability restriction release message in operation 1h-80, the base station 1h-02 may send a new RRC reconfiguration message to the terminal 1h-01 without responding to it.

[0245] In addition to the case where the terminal 1h-01 explicitly requests to release the temporary UE capability change as described above, the base station 1h-02 can recognize the temporary capability change of the terminal in the following cases. The following conditions can be applied to the terminal 1h-01 at the same time.

[0246] 1. When the terminal explicitly requests to release the temporary restriction

[0247] 2. The terminal previously indicated a request for a new temporary restriction

[0248] 3. The terminal switches to the RRC idle state or the RRC inactive state.

[0249] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0250] Fig. 9 is a diagram illustrating a method in which a terminal in an RRC idle state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0251] refer to Fig. 9 Specifically, after the terminal requests temporary UE capability restriction in an operation of requesting to switch from an idle state to a connected state, if the terminal enters an RRC connected state, the terminal requests content of the temporary UE capability restriction.

[0252] In operation 1i-05, the terminal 1i-01 in the RRC idle state may have a temporary change in UE capabilities. Generally, when the terminal is in a connected state, the UE capabilities may change due to sharing hardware with other communication technologies, interference with them, heating, etc. However, even in the idle state, the UE capabilities of the terminal may be affected by the use of other communication technologies (such as WLAN, Bluetooth, etc.), so it is necessary to take this into account for management from the initial RRC connection state. In an embodiment of the present disclosure, even if the UE capabilities temporarily change in the idle state, there is no need to trigger the RRC connection process. Even if the changed UE capabilities are not reported in a state other than the RRC connection state, it does not affect the configuration of the base station. Therefore, the RRC connection process may be triggered only when a general RRC connection is required (when uplink / downlink data occurs). That is, although the temporary change of UE capabilities will not trigger the RRC connection process, if the RRC connection process is triggered due to another reason, it is necessary to determine whether the terminal currently needs a temporary change in UE capabilities, and if the capability change is necessary, the subsequent process reflects the situation. In an embodiment of the present disclosure, in order to notify the base station in advance that the UE capability has been temporarily changed in the idle state, the RRC connection process may be triggered even when the RRC connection is not required.

[0253] Generally, if there is a static UE capability that the terminal reports to the base station in the corresponding operation in the previous RRC connection state, the base station can receive the UE capability from the CN (UE capability retrieval condition 1), in which case the base station may not request the UE capability of the terminal after the RRC connection process. However, if the base station fails to retrieve the static UE capability of the terminal (UE capability retrieval condition 2), the base station may request and receive the UE capability of the terminal after the RRC connection process. Depending on the above conditions, the operations of the base station and the terminal may be different.

[0254] In operation 1i-10, terminal 1i-01 triggers random access to base station 1i-02. That is, terminal 1i-01 sends a random access preamble (msg 1) to base station 1i-02 and starts the RRC connection process. In an embodiment of the present disclosure, a random access preamble (msg 1) can be used to notify temporary capability restrictions. At least one of a predefined preamble ID, time resources, and frequency resources can be used. Alternatively, the random access preamble (msg 1) may include an indicator indicating a temporary capability restriction. In operation 1i-15, terminal 1i-01 receives a random access response (msg 2) from base station 1i-02 and synchronizes the uplink. Thereafter, in operation 1i-20, terminal 1i-01 may include an indicator indicating a temporary capability restriction in an RRC connection establishment request message (msg 3). By including an indicator indicating the presence of a UE capability change in this operation, the base station can pre-identify that terminal 1i-01 will request a temporary capability restriction later.

[0255] In the above operation, msg 3 does not include the details of the temporary capability restriction because msg 3 is size-sensitive and cannot contain a large amount of information. For example, msg 3 may be a message such as an RRC establishment request, an RRC recovery request, an RRC reconstruction request, etc. In the LTE system, a 56-bit msg 3 is used, and the minimum uplink grant size in NR is also 56 bits. For reference, msg 3 must have good link performance within the cell coverage because it is a request message for attempting to connect to the network. In addition, since the size of the packet sent by the terminal 1i-01 is small, the terminal coverage is expanded. Therefore, in the case of allocating an uplink grant of 56 bits or more, the performance of the cell access coverage may deteriorate. As a result, in the NR system, a separate logical channel identifier (LCID) is further allocated to the MAC header to distinguish between a 56-bit uplink grant for common control channel (CCCH) transmission and an uplink grant of 56 bits or more (e.g., 72 bits). However, in the case where a 56-bit uplink grant is allocated, since msg 3 cannot carry and send all of the 5G-S-TMSI which has 8 bits increased compared to the S-TMSI in LTE, msg 3 must send part of the 5G-S-TMSI and msg 5 must send the rest thereof.

[0256] In operation 1i-25, the base station 1i-02 sends an RRC connection establishment message (msg 4) in response to the received RRC connection establishment request message. The message may include radio bearer configuration and MCG configuration (RLC bearer, "mac-CellGroupConfig", "physicalCellGroupConfig and spCellConfig", etc.) for SRB 1. The message includes the general configuration of the base station 1i-02 for SRB 1 in this operation, and the terminal 1i-01 receives msg 4 and sends an RRC connection establishment completion message (msg 5) in response to the configuration of SRB 1 in operation 1i-30. The message may include at least one of the selected PLMN ID, the registered AMF, the globally unique AMF ID (GUAMI) type, the single network slice selection assistance information (S-NSSAI) list, the NAS message, etc. Based on the content of msg 5 sent from terminal 1i-01, base station 1i-02 can retrieve the static capabilities and context of the terminal from CN, and if there is no corresponding UE capability or if base station 1i-02 fails to retrieve the UE capability, base station 1i-02 can request a report on the UE capability. That is, if the above UE capability retrieval condition 1 is met, operations 1i-35, 1i-40 and 1i-45 can be omitted, and operations 1i-35, 1i-40 and 1i-45 can be performed only when UE capability retrieval condition 2 is met.

[0257] In operation 1i-35, the terminal 1i-01 may receive a request to report UE capabilities from the base station 1i-02 via an RRC message. Multiple "UE-CapabilityRAT-Requests" may be sent using the "UECapabilityEnquiry" in the message, or a request for a report on one RAT type may be sent. If multiple "UE-CapabilityRAT-Requests" are sent using "UECapabilityEnquiry" in the above operation, the terminal 1i-01 configures the UE capabilities based on the priority requested according to the RAT type. The request may include frequency band information, restrictions on report content, and the like. For example, the terminal 1i-01 configures the UE capability container in LTE according to the following priority.

[0258] -ue-CapabilityRAT-Container for nr

[0259] -ue-CapabilityRAT-Container for eutra-nr

[0260] -ue-CapabilityRAT-Container for eutra

[0261] If the content of MR-DC is determined, the report of another RAT type has a priority value, and the terminal 1i-01 must report according to the priority value. In the above operation, since the base station 1i-02 knows that the terminal 1i-01 has a temporary change in UE capability by receiving information indicating that the terminal 1i-01 has a temporary change in UE capability in operation 1i-20, the base station 1i-02 can instruct the terminal 1i-01 to report the temporary UE capability. That is, it may include a 1-bit indicator or restriction information that can be reported by reflecting the changed capability. For example, it may include signaling indicating that only permission for restrictions on MIMO, restrictions on the number of CCs, etc. is allowed. In addition, prohibition timer information may be included.

[0262] In operation 1i-40, the terminal 1i-01 sends a "UECapabilityInformation" message to the base station 1i-02, which includes information about the temporarily changed UE capabilities configured according to the priority in its container based on the request of the base station. The message can be sent to the base station 1i-02 via an RRC message, or can be sent using a new message (such as UE auxiliary information, etc.).

[0263] A prohibition timer 1i-45 for prohibiting requests to change UE capabilities can be configured to prevent the terminal 1i-01 from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time. If the prohibition timer is not configured, the terminal 1i-01 may frequently send UE capability reports, which makes it difficult for the base station 1i-02 to perform scheduling and management on the terminal. The prohibition timer 1i-45 can be configured to be included in msg4 during the RRC connection process and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1i-45 can be configured as a default value according to the internal settings of the terminal, or can be obtained from system information. Although not shown, the base station 1i-02 can send a temporary capability restriction confirmation / rejection message in response to the temporary capability restriction request message. If the base station 1i-02 accepts the temporary capability restriction request from the terminal, the base station 1i-02 sends a confirmation message, and if the base station 1i-02 rejects the temporary capability restriction request, the base station 1i-02 sends a rejection message. Both messages can be sent using RRC messages.

[0264] In operation 1i-50, the base station 1i-02 stores or does not reflect the temporary capability limitation information received from the terminal 1i-01 according to whether the temporary capability limitation determined in the operation is reflected. The base station 1i-02 manages the received information only in the access layer (AS) area, and does not send it to the 5G CN 1i-03. However, in an embodiment of the present disclosure, if no UE capability is stored in the 5G CN 1i-03 (UE capability retrieval condition 2), the terminal information may be sent to the 5G CN 1i-03 (operation 1i-55). Thereafter, in the case where the terminal 1i-01 reports static UE capability information, the corresponding information is overwritten by the new static UE capability.

[0265] In operation 1i-60, the base station 1i-02 can reflect the temporary capability restriction and thereby send new RRC configuration information to the terminal 1i-01 through an RRC reconfiguration message. However, if the base station 1i-02 rejects the temporary capability restriction request received from the terminal 1i-01, the base station 1i-02 can omit operation 1i-60 without reflecting the temporary capability restriction, or can configure the RRC reconfiguration based on the original UE capability. That is, the base station 1i-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capability received in the previous operation. The terminal 1i-01 that receives the RRC reconfiguration from the base station 1i-02 in operation 1i-60 sends information indicating that the RRC reconfiguration has been received to the base station 1i-02 through an RRC reconfiguration completion message for the configuration (operation 1i-65).

[0266] If the terminal 1i-01 needs to release the temporary change of UE capabilities in a state where the temporarily changed UE capabilities are reflected through the above-mentioned process of temporarily changing UE capabilities and the RRC reconfiguration according to the process (operation 1i-70), then in operation 1i-75, the terminal 1i-01 notifies the base station 1i-02 through a temporary capability restriction release message that the temporary change of UE capabilities has been completed and the terminal has returned to the original static UE capabilities. Upon receiving the RRC message, the base station 1i-02 may send a release response RRC message indicating that the corresponding release message has been received to the terminal 1i-01 in operation 1i-80. In addition, in operation 1i-85, the base station 1i-02 may determine that the terminal 1i-01 has returned to the static UE capabilities, and may then send a new RRC reconfiguration message to the terminal, or may request new static UE capabilities. Alternatively, the release response message in operation 1i-80 may be omitted. That is, if the base station 1i-02 receives the temporary capability restriction release message in operation 1i-80, the base station 1i-02 may send a new RRC reconfiguration message without responding to it. In operation 1i-90, the terminal 1i-01 that received the UE capability request in operation 1i-85 sends the corresponding information to the base station 1i-02 by including the relevant static UE capabilities in the corresponding information. The base station 1i-02 may store the UE capabilities and may send the UE capabilities to the CN.

[0267] In addition to the case where the terminal 1i-01 explicitly requests to release the temporary UE capability change as described above, the base station 1i-02 may recognize the temporary capability change of the terminal in the following case. The following conditions may be simultaneously applied to the terminal 1i-01.

[0268] 1. When the terminal explicitly requests to release the temporary restriction

[0269] 2. The terminal previously indicated a request for a new temporary restriction

[0270] 3. The terminal switches to the RRC idle state or the RRC inactive state.

[0271] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0272] Fig.10 is a diagram illustrating a method in which a terminal in an RRC idle state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0273] refer to Fig.10 Specifically, in the case where the terminal requests temporary UE capability limitation in the operation of requesting to switch from an idle state to a connected state, the terminal makes the request by including a corresponding indicator in msg 5, and sends the content of the change of UE capability in the connected state.

[0274] In operation 1j-05, the terminal 1j-01 in the RRC idle state may have a temporary change in UE capabilities. Generally, when the terminal is in a connected state, the UE capabilities may change due to sharing hardware with other communication technologies, interference with them, heat generation, etc. However, even in the idle state, the UE capabilities of the terminal may be affected by the use of other communication technologies (such as WLAN, Bluetooth, etc.), so it is necessary to take this into account for management from the initial RRC connection state. In an embodiment of the present disclosure, even if the UE capabilities temporarily change in the idle state, there is no need to trigger the RRC connection process. Even if the changed UE capabilities are not reported in a state other than the RRC connection state, it does not affect the configuration of the base station. Therefore, the RRC connection process may only be triggered when a general RRC connection is required (when uplink / downlink data occurs). That is, although the temporary change of UE capabilities will not trigger the RRC connection process, if the RRC connection process is triggered due to another reason, it is necessary to determine whether the terminal currently needs a temporary change in UE capabilities, and if the capability change is necessary, the subsequent process reflects this situation. In an embodiment of the present disclosure, in order to notify the base station in advance that the UE capability has been temporarily changed in the idle state, the RRC connection process may be triggered even when the RRC connection is not required.

[0275] Generally, if there is a static UE capability that the terminal reports to the base station in the corresponding operation in the previous RRC connection state, the base station can receive the UE capability from the CN (UE capability retrieval condition 1), in which case the base station may not request the UE capability of the terminal after the RRC connection process. However, if the base station fails to retrieve the static UE capability of the terminal (UE capability retrieval condition 2), the base station may request and receive the UE capability of the terminal after the RRC connection process. Depending on the above conditions, the operations of the base station and the terminal may be different.

[0276] In operation 1j-10, the terminal 1j-01 triggers random access to the base station 1j-02. That is, the terminal 1j-01 sends a random access preamble (msg 1) to the base station 1j-02 and starts the RRC connection process. In an embodiment of the present disclosure, the random access preamble (msg 1) can be used to notify a temporary capability restriction. At least one of a predefined preamble ID, time resources, and frequency resources can be used. Alternatively, the random access preamble (msg 1) may include an indicator indicating a temporary capability restriction. In operation 1j-15, the terminal 1j-01 receives a random access response (msg 2) from the base station 1j-02 and synchronizes the uplink. Thereafter, in operation 1j-20, the terminal 1j-01 may send an RRC connection establishment request message (msg 3) to the base station 1j-02.

[0277] In the above operation, msg 3 does not include the details of the temporary capability restriction because msg 3 is size-sensitive and cannot contain a large amount of information. For example, msg 3 may be a message such as an RRC establishment request, an RRC recovery request, an RRC reconstruction request, and the like. In the LTE system, a 56-bit msg 3 is used, and the minimum uplink grant size in NR is also 56 bits. For reference, msg 3 must have good link performance within the cell coverage because it is a request message that attempts to connect to the network. In addition, since the size of the packet sent by terminal 1j-01 is small, the terminal coverage is expanded. Therefore, in the case of allocating 56 bits or more of uplink grants, the performance of the cell access coverage may deteriorate. As a result, in the NR system, a separate logical channel identifier (LCID) is further allocated to the MAC header to distinguish between a 56-bit uplink grant for CCCH transmission and an uplink grant of 56 bits or more (e.g., 72 bits). However, in the case where a 56-bit uplink grant is allocated, since msg 3 cannot carry and send all of the 5G-S-TMSI which has 8 bits increased compared to the S-TMSI in LTE, msg 3 must send part of the 5G-S-TMSI and msg 5 must send the rest thereof.

[0278] In operation 1j-25, the base station 1j-02 sends an RRC connection establishment message (msg 4) in response to the received RRC connection establishment request message. The message may include a radio bearer configuration and an MCG configuration (RLC bearer, "mac-CellGroupConfig", "physicalCellGroupConfig and spCellConfig", etc.) for SRB 1. The message includes the general configuration of the base station 1j-02 used for SRB 1 in this operation, and the terminal 1j-01 receives msg 4 and sends an RRC connection establishment completion message (msg 5) in response to the configuration of SRB 1 in operation 1j-30. The message may include at least one of a selected PLMN ID, a registered AMF, a globally unique AMF ID (GUAMI) type, a single network slice selection assistance information (S-NSSAI) list, a NAS message, etc. According to an embodiment of the present disclosure, the message may include a temporary capability restriction indicator. That is, since the message includes an indicator indicating that the terminal 1j-01 has a temporary change in UE capabilities, the base station 1j-02 can recognize the situation.

[0279] Based on the content of msg 5 sent from terminal 1j-01, base station 1j-02 can retrieve the static capabilities and context of the terminal from CN, and if there is no corresponding UE capability or if base station 1j-02 fails to retrieve the UE capability, base station 1j-02 can request a report on the UE capability. That is, if the above UE capability retrieval condition 1 is met, operations 1j-35, 1j-40 and 1j-45 can be omitted, and operations 1j-35, 1j-40 and 1j-45 can be performed only when UE capability retrieval condition 2 is met.

[0280] In operation 1j-35, the terminal 1j-01 may receive a request to report UE capabilities from the base station 1j-02 via an RRC message. Multiple "UE-CapabilityRAT-Requests" may be sent using the "UECapabilityEnquiry" in the message, or a request for a report on one RAT type may be sent. If "UECapabilityEnquiry" is used in the above operation to send multiple "UE-CapabilityRAT-Requests", the terminal 1j-01 configures the UE capabilities based on the priority requested according to the RAT type. The request may include frequency band information, restrictions on report content, etc. For example, the terminal 1j-01 configures the UE capability container in LTE according to the following priority.

[0281] -ue-CapabilityRAT-Container for nr

[0282] -ue-CapabilityRAT-Container for eutra-nr

[0283] -ue-CapabilityRAT-Container for eutra

[0284] If the content of MR-DC is determined, the report of another RAT type has a priority value and the terminal 1j-01 must report according to the priority value.

[0285] In operation 1j-40, the terminal 1j-01 sends a "UECapabilityInformation" message including UE capability information configured according to the priority in its container to the base station 1j-02. The message is sent to the base station 1j-02 via an RRC message and includes static UE capabilities such as RAT type, frequency band information, etc. requested from the base station 1j-02. Although the terminal 1j-01 can adjust the implementation of UE capabilities for the requested RAT type and frequency band information and report the implementation, in this operation, the terminal basically sends static information about the terminal. This is because in the event that a temporary UE capability restriction request reported later expires, it is necessary to return to the information required for the previous static UE capabilities.

[0286] In operation 1j-45, the base station 1j-02 sends the UE capability information received from the terminal 1j-01 to the 5G CN 1j-03, and the 5G CN 1j-03 stores the received static UE capability information. The UE capability information stored in the 5G CN 1j-03 in the above operation can be maintained until the RRC connection of the terminal 1j-01 is released, and can be used for service configuration and mobility management regarding the terminal.

[0287] Fundamentally, the UE capabilities are statically sent to the base station 1j-02 and the 5G CN 1j-03, and if there is no separate signaling, the inherent capabilities of the terminal 1j-01 remain unchanged. However, in the case of the actual terminal 1j-01, due to the above four reasons and other reasons, the UE capabilities may need to be temporarily changed. That is, due to sharing hardware with other communication modules in the terminal, interference with them, temporary heating, changes in terminal mode, etc., a temporary change in UE capabilities that is different from the static terminal performance may be generated / needed. Generally, in the case where the UE capability is temporarily reduced compared to the static UE capability, the terminal needs to report the situation to the base station to request scheduling and management that conforms to the reduced UE capability. However, in certain cases, the terminal may have a higher UE capability than the static UE capability that the terminal has reported. For example, in the case of a foldable terminal, if the performance of the terminal is the static UE capability when the display is folded, the performance of the terminal in the state where the display is unfolded can be configured to be higher. That is, the change in the state of the terminal can produce differences in the performance of the antenna and MIMO applied to the terminal, the power performance of the terminal, etc. In order to support the above situation, in addition to the existing method of reporting UE capabilities, a new signaling structure and its functions are also required.

[0288] An embodiment proposes a method in which a terminal in a connected state requests a temporary capability restriction through an RRC message. In operation 1j-50, the terminal 1j-01 sends information about a temporary change in UE capability (i.e., temporary capability restriction) and a request for it through an RRC message (such as UE auxiliary information). The RRC message may include at least one piece of information that the terminal 1j-01 can request, such as the reason for requesting a temporary change in UE capability (e.g., reason value: hardware sharing, interference, overheating, mode change, etc.), frequency bands and frequency band combination information to be supported, changes in the physical functions of the terminal (changes in the number of component carriers, changes in the number of MIMO layers, changes in the frequency bands and bandwidth information to be supported by each CC, changes in supported power, changes in the frequency range to be supported, etc.), etc. The detailed items included in the RRC message and its signaling method will be described in more detail in another embodiment below.

[0289] When a terminal reports a change in UE capabilities, if only UE capabilities with a temporary change less than the static UE capabilities are reported, only a subset of the static UE capabilities may always be reported. That is, this is a request to temporarily have some reduced capabilities of the overall static UE capabilities. However, if UE capabilities with a temporary change higher than the static UE capabilities may be reported, then new UE capabilities higher than those reported in the previous static report must be signaled.

[0290] In addition, a prohibition timer 1j-55 for prohibiting requests to change UE capabilities can be configured to prevent the terminal 1j-01 from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time accordingly. If the prohibition timer is not configured, the terminal 1j-01 may frequently send UE capability reports, which makes it difficult for the base station 1j-02 to perform scheduling and management of the terminal 1j-01. The prohibition timer 1j-55 can be configured to be included in msg 4 during the RRC connection process, and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1j-55 can be configured to a default value according to the internal settings of the terminal, or can be obtained from system information. Although not shown, the base station 1j-02 can send a temporary capability restriction confirmation / rejection message in response to the temporary capability restriction request message. If the base station 1j-02 accepts the temporary capability restriction request from the terminal 1j-01, the base station 1j-02 sends a confirmation message to the terminal 1j-01. If the base station 1j-02 rejects the temporary capability restriction request, the base station 1j-02 sends a rejection message. Both messages can be sent using RRC messages.

[0291] In operation 1j-60, the base station 1j-02 stores or does not reflect the temporary capability limitation information received from the terminal 1j-01 according to whether the temporary capability limitation determined in the operation is reflected. The base station 1j-02 manages the received information only in the access layer (AS) area, and does not send it to the 5G CN 1j-03. In operation 1j-65, the base station 1j-02 can reflect the temporary capability limitation, thereby sending new RRC configuration information to the terminal 1j-01 through an RRC reconfiguration message. However, if the base station 1j-02 rejects the temporary capability limitation request received from the terminal 1j-01, the base station 1j-02 can omit operation 1j-65 without reflecting the temporary capability limitation, or can configure the RRC reconfiguration based on the original UE capability. That is, the base station 1j-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capability received in the previous operation 1j-10. The terminal 1j-01 that receives the RRC reconfiguration from the base station 1j-02 in operation 1j-65 sends information indicating that the RRC reconfiguration has been received to the base station 1j-02 through an RRC reconfiguration completion message for the configuration (operation 1j-70).

[0292] If the terminal 1j-01 needs to release the temporary change of UE capabilities in a state where the temporarily changed UE capabilities are reflected through the above-mentioned process of temporarily changing UE capabilities and the RRC reconfiguration according to the process (operation 1j-75), then in operation 1j-80, the terminal 1j-01 notifies the base station 1j-02 through a temporary capability restriction release message that the temporary change of UE capabilities has been completed and the terminal has returned to the original static UE capabilities. Upon receiving the RRC message, the base station 1j-02 may send a release response RRC message to the terminal 1j-01 in operation 1j-85 indicating that the corresponding release message has been received. In addition, in operation 1j-90, the base station 1j-02 may determine that the terminal 1j-01 has returned to the static UE capabilities, and may then send a new RRC reconfiguration message. Alternatively, the release response message in operation 1j-85 may be omitted. That is, if the base station 1j-02 receives a temporary capability restriction release message in operation 1j-80, the base station 1j-02 can send a new RRC reconfiguration message to the terminal 1j-01 without responding to it.

[0293] In addition to the case where the terminal 1j-01 explicitly requests to release the temporary UE capability change as described above, the base station 1j-02 can recognize the temporary capability change of the terminal in the following cases. The following conditions can be applied to the terminal 1j-01 at the same time.

[0294] 1. When the terminal explicitly requests to release the temporary restriction

[0295] 2. The terminal previously indicated a request for a new temporary restriction

[0296] 3. The terminal switches to the RRC idle state or the RRC inactive state.

[0297] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0298] Fig.11 is a diagram illustrating a method in which a terminal in an RRC idle state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0299] refer to Fig.11, specifically, in case that the terminal requests temporary capability restriction in an operation of requesting to switch from an idle state to a connected state, the terminal makes the request by including relevant information.

[0300] In operation 1k-05, the terminal 1k-01 in the RRC idle state may have a temporary change in UE capabilities. Generally, when the terminal is in a connected state, the UE capabilities may change due to sharing hardware with other communication technologies, interference with them, heat generation, etc. However, even in the idle state, the UE capabilities of the terminal may be affected by the use of other communication technologies (such as WLAN, Bluetooth, etc.), so it is necessary to take this into account for management from the initial RRC connection state. In an embodiment of the present disclosure, even if the UE capabilities temporarily change in the idle state, there is no need to trigger the RRC connection process. Even if the changed UE capabilities are not reported in a state other than the RRC connection state, it does not affect the configuration of the base station. Therefore, the RRC connection process may be triggered only when a general RRC connection is required (when uplink / downlink data occurs). That is, although the temporary change of UE capabilities will not trigger the RRC connection process, if the RRC connection process is triggered due to another reason, it is necessary to determine whether the terminal currently needs a temporary change in UE capabilities, and if the capability change is necessary, the subsequent process reflects this situation.

[0301] Generally, if there is a static UE capability that the terminal reports to the base station in the corresponding operation in the previous RRC connection state, the base station can receive the UE capability from the CN (UE capability retrieval condition 1), in which case the base station may not request the UE capability of the terminal after the RRC connection process. However, if the base station fails to retrieve the static UE capability of the terminal (UE capability retrieval condition 2), the base station may request and receive the UE capability of the terminal after the RRC connection process. Depending on the above conditions, the operations of the base station and the terminal may be different.

[0302] In operation 1k-10, terminal 1k-01 triggers random access to base station 1k-02. That is, terminal 1k-01 sends a random access preamble (msg 1) to base station 1k-02 and starts the RRC connection process. In an embodiment of the present disclosure, a random access preamble (msg 1) can be used to notify temporary capability restrictions. At least one of a predefined preamble ID, time resources, and frequency resources can be used. Alternatively, the random access preamble (msg 1) may include an indicator indicating a temporary capability restriction. In operation 1k-15, terminal 1k-01 receives a random access response (msg 2) from base station 1k-02 and synchronizes the uplink. Thereafter, in operation 1k-20, terminal 1k-01 may include an indicator indicating a temporary capability restriction in an RRC connection establishment request message (msg 3). By including an indicator indicating the presence of a UE capability change in this operation, the base station can pre-identify that terminal 1k-01 will request a temporary capability restriction later.

[0303] In the above operation, msg 3 does not include the details of the temporary capability restriction because msg 3 is size-sensitive and cannot contain a large amount of information. For example, msg 3 may be a message such as an RRC establishment request, an RRC recovery request, an RRC reconstruction request, and the like. In the LTE system, a 56-bit msg 3 is used, and the minimum uplink grant size in NR is also 56 bits. For reference, msg 3 must have good link performance within the cell coverage because it is a request message trying to connect to the network. In addition, since the size of the packet sent by the terminal 1k-01 is small, the terminal coverage is expanded. Therefore, in the case of allocating 56 bits or more of uplink grants, the performance of the cell access coverage may deteriorate. As a result, in the NR system, a separate logical channel identifier (LCID) is further allocated to the MAC header to distinguish between a 56-bit uplink grant for CCCH transmission and an uplink grant of 56 bits or more (e.g., 72 bits). However, in the case where a 56-bit uplink grant is allocated, since msg 3 cannot carry and send all of the 5G-S-TMSI which has 8 bits increased compared to the S-TMSI in LTE, msg 3 must send part of the 5G-S-TMSI and msg 5 must send the rest thereof.

[0304] In operation 1k-25, the base station 1k-02 sends an RRC connection establishment message (msg 4) in response to the received RRC connection establishment request message. The message may include radio bearer configuration and MCG configuration (RLC bearer, "mac-CellGroupConfig", "physicalCellGroupConfig and spCellConfig", etc.) for SRB 1. The message includes the general configuration of the base station 1k-02 used for SRB 1 in this operation, and the terminal 1k-01 receives msg 4 and sends an RRC connection establishment completion message (msg 5) in response to the configuration of SRB 1 (operation 1k-30). The message may include at least one of the selected PLMN ID, registered AMF, globally unique AMF ID (GUAMI) type, single network slice selection assistance information (S-NSSAI) list, NAS message, etc., and may include temporary capability restriction information. This situation can be established in a state where the terminal has reported static UE capabilities to the base station in a previous connection state (UE capability retrieval condition 1), or it can be established in a state where there is no previous information. The RRC message may include at least one piece of information that the terminal 1k-01 may request, such as a reason for requesting a temporary change in UE capabilities (e.g., reason value: hardware sharing, interference, overheating, mode change, etc.), frequency bands to be supported and frequency band combination information, changes in physical functions of the terminal (changes in the number of component carriers, changes in the number of MIMO layers, changes in frequency bands and bandwidth information to be supported by each CC, changes in supported power, changes in frequency ranges to be supported, etc.), etc. The detailed items included in the RRC message and their signaling methods will be described in more detail below in another embodiment.

[0305] When a terminal reports a change in UE capabilities, if only UE capabilities with a temporary change less than the static UE capabilities are reported, only a subset of the static UE capabilities may always be reported. That is, this is a request to temporarily have some reduced capabilities of the overall static UE capabilities. However, if UE capabilities with a temporary change higher than the static UE capabilities may be reported, then new UE capabilities higher than those reported in the previous static report must be signaled.

[0306] In addition, a prohibition timer 1k-35 for prohibiting requests to change UE capabilities can be configured to prevent the terminal 1k-01 from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time. If the prohibition timer is not configured, the terminal 1k-01 may frequently send UE capability reports, which makes it difficult for the base station 1k-02 to perform scheduling and management of the terminal. The prohibition timer 1k-35 can be configured to be included in msg 4 during the RRC connection process, and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1k-35 can be configured as a default value according to the internal settings of the terminal, or can be obtained from system information.

[0307] In operation 1k-40, the base station 1k-02 stores or does not reflect the temporary capability limitation information received from the terminal 1k-01 according to whether the temporary capability limitation determined in the operation is reflected. Based on the content of msg 5 sent from the terminal 1k-01, the base station 1k-02 can retrieve the static capabilities and context of the terminal from the core network (CN), and if there is no corresponding UE capability or if the base station 1k-02 fails to retrieve the UE capability, the base station 1k-02 can request a report on the UE capability. That is, if the above UE capability retrieval condition 1 is met, operations 1k-45, 1k-50 and 1k-55 can be omitted, and operations 1k-45, 1k-50 and 1k-55 can be performed only when the UE capability retrieval condition 2 is met.

[0308] In operation 1k-45, the terminal 1k-01 may receive a request to report UE capabilities from the base station 1k-02 via an RRC message. Multiple "UE-CapabilityRAT-Requests" may be sent using the "UECapabilityEnquiry" in the message, or a request for a report on one RAT type may be sent. If "UECapabilityEnquiry" is used in the above operation to send multiple "UE-CapabilityRAT-Requests", the terminal 1k-01 configures the UE capabilities based on the priority requested according to the RAT type. The request may include frequency band information, restrictions on report content, and the like. For example, the terminal 1k-01 configures the UE capability container in LTE according to the following priority.

[0309] -ue-CapabilityRAT-Container for nr

[0310] -ue-CapabilityRAT-Container for eutra-nr

[0311] -ue-CapabilityRAT-Container for eutra

[0312] If the content of MR-DC is determined, the report of another RAT type has a priority value and the terminal must report according to the priority value.

[0313] In operation 1k-50, the terminal 1k-01 sends a "UECapabilityInformation" message including UE capability information configured according to the priority in its container to the base station 1k-02. The message is sent to the base station 1k-02 via an RRC message and includes static UE capabilities such as RAT type, frequency band information, etc. requested from the base station 1k-02. Although the terminal 1k-01 can adjust the implementation of UE capabilities for the requested RAT type and frequency band information and report the implementation, in this operation, the terminal 1k-01 basically sends static information about the terminal. This is because in the event that a temporary UE capability restriction request reported later expires, it is necessary to return to the information required for the previous static UE capabilities.

[0314] In operation 1k-55, the base station 1k-02 sends the UE capability information received from the terminal 1k-01 to the 5G CN 1k-03, and the 5G CN 1k-03 stores the received static UE capability information. The UE capability information stored in the 5G CN 1k-03 in the above operation can be maintained until the RRC connection of the terminal 1k-01 is released, and can be used for service configuration and mobility management of the terminal 1k-01. In this case, the base station 1k-02 does not send the temporary capability restriction information received from the terminal 1k-01 in operation 1k-30 to the CN.

[0315] In operation 1k-60, the base station 1k-02 may reflect the temporary capability restriction received in operation 1k-30, thereby sending new RRC configuration information to the terminal 1k-01 through an RRC reconfiguration message. However, if the base station 1k-02 rejects the temporary capability restriction request received from the terminal 1k-01, the base station 1k-02 may omit operation 1k-60 without reflecting the temporary capability restriction, or may configure the RRC reconfiguration based on the original UE capability. That is, the base station 1k-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capability received in the previous operation. The terminal 1k-01 that receives the RRC reconfiguration from the base station 1k-02 in operation 1k-60 sends information indicating that the RRC reconfiguration has been received to the base station 1k-02 through an RRC reconfiguration completion message for the configuration (operation 1k-65).

[0316] If the terminal 1k-01 needs to release the temporary change of UE capabilities in a state where the temporarily changed UE capabilities are reflected through the above-mentioned process of temporarily changing UE capabilities and the RRC reconfiguration according to the process (operation 1k-70), then in operation 1k-75, the terminal 1k-01 notifies the base station 1k-02 through a temporary capability restriction release message that the temporary change of UE capabilities has been completed and the terminal has returned to the original static UE capabilities. Upon receiving the RRC message, the base station 1k-02 may send a release response RRC message to the terminal 1k-01 in operation 1k-80 indicating that the corresponding release message has been received. In operation 1k-85, the base station 1k-02 may determine that the terminal 1k-01 has returned to the static UE capabilities, and may then send a new RRC reconfiguration message to the terminal 1k-01. Alternatively, the release response message in operation 1j-85 may be omitted. That is, if the base station 1k-02 receives a temporary capability restriction release message in operation 1k-75, the base station 1k-02 can send a new RRC reconfiguration message to the terminal 1k-01 without responding to it.

[0317] In addition to the case where the terminal 1k-01 explicitly requests to release the temporary UE capability change as described above, the base station 1k-02 can identify the temporary capability change of the terminal 1k-01 in the following cases. The following conditions can be applied to the terminal 1k-01 at the same time.

[0318] 1. When the terminal explicitly requests to release the temporary restriction

[0319] 2. The terminal previously indicated a request for a new temporary restriction

[0320] 3. The terminal switches to the RRC idle state or the RRC inactive state.

[0321] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0322] For example, if the terminal's capabilities change again in operation 1k-90, terminal 1k-01 sends information about the temporary change of UE capabilities (i.e., temporary capability limitation) and a request for it to base station 1k-02 through an RRC message (such as UE assistance information) in operation 1k-95.

[0323] Fig.12 is a diagram illustrating a method in which a terminal in an RRC idle state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0324] refer to Fig.12 Specifically, after the terminal requests temporary UE capability restriction in an operation of requesting to switch from an idle state to a connected state, if the terminal enters an RRC connected state, the terminal requests content of the temporary UE capability restriction.

[0325] In operation 11-05, the terminal 11-01 in the RRC idle state may have a temporary change in UE capabilities. Generally, when the terminal is in a connected state, the UE capabilities may change due to sharing hardware with other communication technologies, interference with them, heating, etc. However, even in the idle state, the UE capabilities of the terminal may also be affected by the use of other communication technologies (such as WLAN, Bluetooth, etc.), so it is necessary to take this into account and manage from the initial RRC connection state. In an embodiment of the present disclosure, even if the UE capabilities are temporarily changed in the idle state, it is not necessary to trigger the RRC connection process. Even if the changed UE capabilities are not reported in a state other than the RRC connection state, it does not affect the configuration of the base station. Therefore, the RRC connection process may be triggered only when a general RRC connection is required (when uplink / downlink data occurs). That is, although the temporary change of UE capabilities will not trigger the RRC connection process, if the RRC connection process is triggered due to another reason, it is necessary to determine whether the terminal currently needs a temporary change in UE capabilities, and if the capability change is necessary, the subsequent process reflects the situation. In an embodiment of the present disclosure, in order to notify the base station in advance that the UE capability has been temporarily changed in the idle state, the RRC connection process may be triggered even when the RRC connection is not required.

[0326] Generally, if there is a static UE capability that the terminal reports to the base station in the corresponding operation in the previous RRC connection state, the base station can receive the UE capability from the CN (UE capability retrieval condition 1), in which case the base station may not request the UE capability of the terminal after the RRC connection process. However, if the base station fails to retrieve the static UE capability of the terminal (UE capability retrieval condition 2), the base station may request and receive the UE capability of the terminal after the RRC connection process. Depending on the above conditions, the operations of the base station and the terminal may be different.

[0327] In operation 1l-10, terminal 1l-01 triggers random access to base station 1l-02. That is, terminal 1l-01 sends a random access preamble (msg 1) to base station 1l-02 and starts the RRC connection process. In an embodiment of the present disclosure, a random access preamble (msg 1) can be used to notify temporary capability restrictions. At least one of a predefined preamble ID, time resources, and frequency resources can be used. Alternatively, the random access preamble (msg 1) may include an indicator indicating a temporary capability restriction. In operation 1l-15, terminal 1l-01 receives a random access response (msg 2) from base station 1l-02 and synchronizes the uplink. Thereafter, in operation 1l-20, terminal 1l-01 sends an RRC connection establishment request message (msg 3).

[0328] In the above operation, msg 3 does not include the details of the temporary capability restriction because msg 3 is size-sensitive and cannot contain a large amount of information. For example, msg 3 may be a message such as an RRC establishment request, an RRC recovery request, an RRC reconstruction request, etc. In the LTE system, a 56-bit msg 3 is used, and the minimum uplink grant size in NR is also 56 bits. For reference, msg 3 must have good link performance within the cell coverage because it is a request message that attempts to connect to the network. In addition, since the size of the packet sent by terminal 1l-01 is small, the terminal coverage is expanded. Therefore, in the case of allocating 56 bits or more of uplink grants, the performance of the cell access coverage may deteriorate. As a result, in the NR system, a separate logical channel identifier (LCID) is further allocated to the MAC header to distinguish between a 56-bit uplink grant for CCCH transmission and an uplink grant of 56 bits or more (e.g., 72 bits). However, in the case where a 56-bit uplink grant is allocated, since msg 3 cannot carry and send all of the 5G-S-TMSI which has 8 bits increased compared to the S-TMSI in LTE, msg 3 must send part of the 5G-S-TMSI and msg 5 must send the rest thereof.

[0329] In operation 11-25, the base station 11-02 sends an RRC connection establishment message (msg 4) in response to the received RRC connection establishment request message. The message may include a radio bearer configuration and an MCG configuration (RLC bearer, "mac-CellGroupConfig", "physicalCellGroupConfig and spCellConfig", etc.) for SRB 1. The message includes a general configuration of the base station 11-02 for SRB 1 in this operation, and the terminal 11-01 receives msg 4 and sends an RRC connection establishment completion message (msg 5) in response to the configuration of SRB 1 in operation 11-30. The message may include at least one of a selected PLMN ID, a registered AMF, a globally unique AMF ID (GUAMI) type, a single network slice selection assistance information (S-NSSAI) list, a NAS message, etc., and may include an indicator indicating a temporary capability restriction. By including an indicator indicating that there is a UE capability change in this operation, the base station can pre-identify that the terminal will request a temporary capability restriction later. Based on the content of msg 5 sent from terminal 11-01, base station 11-02 can retrieve the static capabilities and context of the terminal from CN, and if there is no corresponding UE capability or if base station 11-02 fails to retrieve the UE capability, base station 11-02 can request a report on the UE capability. That is, if the above UE capability retrieval condition 1 is met, operations 11-35, 11-40 and 11-45 can be omitted, and operations 11-35, 11-40 and 11-45 can be performed only when UE capability retrieval condition 2 is met.

[0330] In operation 1l-35, the terminal 1l-01 may receive a request to report UE capabilities from the base station 1l-02 via an RRC message. Multiple "UE-CapabilityRAT-Requests" may be sent using the "UECapabilityEnquiry" in the message, or a request for a report on one RAT type may be sent. If multiple "UE-CapabilityRAT-Requests" are sent using "UECapabilityEnquiry" in the above operation, the terminal 1l-01 configures the UE capabilities based on the priority requested according to the RAT type. The request may include frequency band information, restrictions on report content, etc. For example, the terminal 1l-01 configures the UE capability container in LTE according to the following priority.

[0331] -ue-CapabilityRAT-Container for nr

[0332] -ue-CapabilityRAT-Container for eutra-nr

[0333] -ue-CapabilityRAT-Container for eutra

[0334] If the content of MR-DC is determined, the report of another RAT type has a priority value, and the terminal 1l-01 must report according to the priority value. In the above operation, since the base station 1l-02 knows that the terminal 1l-01 has a temporary change in UE capability by receiving information indicating that the terminal 1l-01 has a temporary change in UE capability in operation 1l-20, the base station 1l-02 can instruct the terminal 1l-01 to report the temporary UE capability. That is, it may include a 1-bit indicator or restriction information that can be reported by reflecting the changed capability. For example, it may include signaling indicating that only permission for restrictions on MIMO, restrictions on the number of CCs, etc. is allowed. In addition, prohibition timer information may be included.

[0335] In operation 11-40, the terminal 11-01 sends a "UECapabilityInformation" message to the base station 11-02, which includes information about the temporarily changed UE capabilities configured according to the priority in its container based on the request of the base station 11-02. The message can be sent to the base station 11-02 via an RRC message, or can be sent using a new message (such as UE auxiliary information, etc.).

[0336] A prohibition timer 1l-45 for prohibiting requests to change UE capabilities can be configured to prevent the terminal 1l-01 from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time. If the prohibition timer is not configured, the terminal 1l-01 may frequently send UE capability reports, which makes it difficult for the base station 1l-02 to perform scheduling and management on the terminal 1l-01. The prohibition timer 1l-45 can be configured to be included in msg4 during the RRC connection process, and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1l-45 can be configured to a default value according to the internal settings of the terminal, or can be obtained from system information. Although not shown, the base station 1l-02 can send a temporary capability restriction confirmation / rejection message in response to the temporary capability restriction request message. If the base station 11-02 accepts the temporary capability restriction request from the terminal 11-01, the base station 11-02 sends a confirmation message to the terminal 11-01, and if the base station 11-02 rejects the temporary capability restriction request, the base station 11-02 sends a rejection message. Both messages can be sent using RRC messages.

[0337] In operation 11-50, the base station 11-02 stores or does not reflect the temporary capability limitation information received from the terminal 11-01 according to whether the temporary capability limitation determined in the operation is reflected. The base station 11-02 manages the received information only in the access layer (AS) area without sending it to the 5G CN 11-03. However, in an embodiment of the present disclosure, if no UE capability is stored in the 5G CN 11-03 (UE capability retrieval condition 2), the terminal information may be sent to the 5G CN 11-03 (operation 11-55). Thereafter, in the case where the terminal 11-01 reports static UE capability information, the corresponding information is overwritten by the new static UE capability.

[0338] In operation 11-60, the base station 11-02 can reflect the temporary capability restriction, thereby sending new RRC configuration information to the terminal 11-01 through an RRC reconfiguration message. However, if the base station 11-02 rejects the temporary capability restriction request received from the terminal 11-01, the base station 11-02 can omit operation 11-60 without reflecting the temporary capability restriction, or can configure the RRC reconfiguration based on the original UE capability. That is, the base station 11-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capability received in the previous operation. The terminal 11-01 that receives the RRC reconfiguration from the base station 11-02 in operation 11-60 sends information indicating that the RRC reconfiguration has been received to the base station 11-02 through an RRC reconfiguration completion message for the configuration (operation 11-65).

[0339] If the terminal 11-01 needs to release the temporary change of UE capability in the state of reflecting the temporarily changed UE capability through the above-mentioned process of temporarily changing UE capability and RRC reconfiguration according to the process (operation 11-70), then in operation 11-75, the terminal 11-01 notifies the base station 11-02 through a temporary capability restriction release message that the temporary change of UE capability has been completed and the terminal has returned to the original static UE capability. Upon receiving the RRC message, the base station 11-02 can send a release response RRC message indicating that the corresponding release message has been received to the terminal 11-01 in operation 11-80.

[0340] In operation 11-85, the base station 11-02 may determine that the terminal 11-01 has returned to the static UE capabilities, and may then send a new RRC reconfiguration message to the terminal, or may request new static UE capabilities. Alternatively, the release response message in operation 11-80 may be omitted. That is, if the base station 11-02 receives a temporary capability restriction release message in operation 11-80, the base station 11-02 may send a new RRC reconfiguration message without responding to it. In operation 11-90, the terminal 11-01 that receives the UE capability request in operation 11-85 sends the corresponding information to the base station 11-02 by including the relevant static UE capabilities in the corresponding information. The base station 11-02 may store the UE capabilities, and may send the UE capabilities to the CN.

[0341] In addition to the case where the terminal 11-01 explicitly requests to release the temporary UE capability change as described above, the base station 11-02 can identify the temporary capability change of the terminal in the following cases. The following conditions can be applied to the terminal 11-01 at the same time.

[0342] 1. When the terminal explicitly requests to release the temporary restriction

[0343] 2. The terminal previously indicated a request for a new temporary restriction

[0344] 3. The terminal switches to the RRC idle state or the RRC inactive state.

[0345] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0346] Fig.13 is a diagram illustrating a method in which a terminal in an RRC inactive state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0347] refer to Fig.13 Specifically, after the terminal requests temporary UE capability restriction in an operation of requesting to switch from an inactive state to a connected state, if the terminal enters an RRC connected state, the terminal requests temporary UE capability restriction.

[0348] In operation 1m-05, the terminal 1m-01 in the RRC inactive state may have a temporary change in UE capabilities. Generally, when the terminal is in a connected state, the UE capabilities may change due to sharing hardware with other communication technologies, interference with them, heat generation, etc. However, even in an inactive state, the UE capabilities may be affected by the use of other communication technologies (such as WLAN, Bluetooth, etc.), so it is necessary to take this into account for management from the initial RRC connection state. In an embodiment of the present disclosure, even if the UE capabilities temporarily change in an inactive state, there is no need to trigger the RRC recovery process. Even if the changed UE capabilities are not reported in a state other than the RRC connection state, it does not affect the configuration of the base station. Therefore, the RRC recovery process may only be triggered when a general RRC connection is required (when uplink / downlink data occurs). That is, although the temporary change of UE capabilities will not trigger the RRC recovery process, if the RRC recovery process is triggered due to another reason, it is necessary to determine whether the terminal currently needs a temporary change in UE capabilities, and if the capability change is necessary, the subsequent process reflects this situation.

[0349] In an embodiment of the present disclosure, in order to notify the base station in advance that the UE capability has been temporarily changed in an inactive state, the RRC connection process may be triggered even when the RRC connection is not required.

[0350] Generally, if there is a static UE capability that the terminal reports to the base station in the corresponding operation in the previous RRC connection state, the base station can receive the UE capability from the CN (UE capability retrieval condition 1), in which case the base station may not request the UE capability of the terminal after the RRC connection process. However, if the base station fails to retrieve the static UE capability of the terminal (UE capability retrieval condition 2), the base station may request and receive the UE capability of the terminal after the RRC connection process. Depending on the above conditions, the operations of the base station and the terminal may be different.

[0351] In operation 1m-10, the terminal 1m-01 may include an indicator indicating a temporary capability restriction in the RRC recovery request message (msg 3). By including an indicator indicating the presence of a UE capability change in this operation, the base station can pre-identify that the terminal 1m-01 will request a temporary capability restriction later. In the above operation, msg 3 does not include the details of the temporary capability restriction because msg 3 is size sensitive and cannot contain a large amount of information. For example, msg 3 may be a message such as an RRC establishment request, an RRC recovery request, an RRC reconstruction request, etc. In operation 1m-15, the base station 1m-02 sends a retrieval message to 5G CN 1m-03 for determining whether there is context and UE capability information of the terminal stored in 5G CN 1m-03 and requesting the context and UE capability information of the terminal, and receives a response to the retrieval message from 5G CN 1m-03 in operation 1m-20. If the information exists, the base station 1m-02 stores the static UE capabilities.

[0352] In operation 1m-25, the base station 1m-02 sends an RRC recovery message (msg 4) in response to the received RRC recovery request message. The message may include radio bearer configuration and MCG configuration (RLC bearer, "mac-CellGroupConfig", "physicalCellGroupConfig and spCellConfig", etc.) for SRB 1. The message includes the general configuration of the base station 1m-02 used for SRB 1 in this operation, and the terminal 1m-01 receives msg 4 and sends an RRC recovery complete message (msg 5) in response to the configuration of SRB 1 in operation 1m-30. The message may include at least one of a selected PLMN ID, a NAS message, etc. Based on the content of msg 5 sent from the terminal 1m-01, the base station 1m-02 can retrieve the static capabilities and context of the terminal from the CN, and if there is no corresponding UE capability or if the base station 1m-02 fails to retrieve the UE capability, the base station 1m-02 can request a report on the UE capability.

[0353] In operation 1m-35, the terminal 1m-01 may request a temporary change in UE capabilities from the base station 1m-02. Information about the temporary change in UE capabilities (i.e., temporary capability limitation) and a request for a temporary change in UE capabilities may be sent via an RRC message (such as the UE auxiliary information in the above operation). The RRC message may include at least one piece of information that the terminal 1m-01 may request, such as the reason for requesting a temporary change in UE capabilities (e.g., reason value: hardware sharing, interference, overheating, mode change, etc.), frequency bands and frequency band combination information to be supported, changes in the physical functions of the terminal (changes in the number of component carriers, changes in the number of MIMO layers, changes in the frequency bands and bandwidth information to be supported by each CC, changes in supported power, changes in the frequency range to be supported, etc.), etc. The detailed items included in the RRC message and their signaling methods will be described in more detail in another embodiment below.

[0354] When a terminal reports a change in UE capabilities, if only UE capabilities with a temporary change less than the static UE capabilities are reported, only a subset of the static UE capabilities may always be reported. That is, this is a request to temporarily have some reduced capabilities of the overall static UE capabilities. However, if UE capabilities with a temporary change higher than the static UE capabilities may be reported, then new UE capabilities higher than those reported in the previous static report must be signaled.

[0355] In addition, a prohibition timer 1m-40 for prohibiting requests to change UE capabilities can be configured to prevent the terminal 1m-01 from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time. If the prohibition timer is not configured, the terminal 1m-01 may frequently send UE capability reports, which makes it difficult for the base station 1m-02 to perform scheduling and management of the terminal. The prohibition timer 1m-40 can be configured to be included in msg 4 during the RRC connection process, and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1m-40 can be configured to a default value according to the internal settings of the terminal, or can be obtained from system information. Although not shown, the base station 1m-02 can send a temporary capability restriction confirmation / rejection message to the terminal 1m-01 in response to the temporary capability restriction request message. If the base station 1m-02 accepts the temporary capability restriction request from the terminal 1m-01, the base station 1m-02 sends a confirmation message to the terminal 1m-01, and if the base station 1m-02 rejects the temporary capability restriction request, the base station 1m-02 sends a rejection message to the terminal 1m-01. Both messages can be sent using RRC messages.

[0356] In operation 1m-45, the base station 1m-02 stores or does not reflect the temporary capability limitation information received from the terminal 1m-01 according to whether the temporary capability limitation determined in the operation is reflected. The base station 1m-02 manages the received information only in the access layer (AS) area, and does not send it to the 5G CN 1m-03. In operation 1m-50, the base station 1m-02 can reflect the temporary capability limitation, thereby sending new RRC configuration information to the terminal 1m-01 through an RRC reconfiguration message. However, if the base station 1m-02 rejects the temporary capability limitation request received from the terminal 1m-01, the base station 1m-02 can omit operation 1m-50 without reflecting the temporary capability limitation, or can configure the RRC reconfiguration based on the original UE capability. That is, the base station 1m-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capability received in the previous operation. The terminal 1m-01 that has received the RRC reconfiguration from the base station 1m-02 in operation 1m-50 sends information indicating that the RRC reconfiguration has been received to the base station 1m-02 through an RRC reconfiguration complete message for the configuration (operation 1m-55).

[0357] If the terminal 1m-01 needs to release the temporary change of UE capabilities in a state where the temporarily changed UE capabilities are reflected through the above-mentioned process of temporarily changing UE capabilities and the RRC reconfiguration according to the process (operation 1m-60), then in operation 1m-65, the terminal 1m-01 notifies the base station 1m-02 through a temporary capability restriction release message that the temporary change of UE capabilities has been completed and the terminal has returned to the original static UE capabilities. Upon receiving the RRC message, the base station 1m-02 can send a release response RRC message to the terminal 1m-01 in operation 1m-70 indicating that the corresponding release message has been received.

[0358] In operation 1m-75, the base station 1m-02 may determine that the terminal 1m-01 has returned to the static UE capability, and may then send a new RRC reconfiguration message to the terminal 1m-01. Alternatively, the release response message in operation 1m-70 may be omitted. That is, if the base station 1m-02 receives the temporary capability restriction release message in operation 1m-65, the base station 1m-02 may send a new RRC reconfiguration message without responding to it.

[0359] In addition to the case where the terminal 1m-01 explicitly requests to release the temporary UE capability change as described above, the base station 1m-02 can recognize the temporary capability change of the terminal in the following cases. The following conditions can be applied to the terminal 1m-01 at the same time.

[0360] 1. When the terminal explicitly requests to release the temporary restriction

[0361] 2. The terminal previously indicated a request for a new temporary restriction

[0362] 3. The terminal switches to the RRC idle state or the RRC inactive state.

[0363] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0364] Fig.14 is a diagram illustrating a method in which a terminal in an RRC inactive state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0365] refer to Fig.14 Specifically, after the terminal requests temporary UE capability restriction in an operation of requesting to switch from an inactive state to a connected state, if the terminal enters an RRC connected state, the base station requests the content of the temporary UE capability restriction.

[0366] In operation 1n-05, the terminal 1n-01 in the RRC inactive state may have a temporary change in UE capabilities. Generally, when the terminal is in a connected state, the UE capabilities may change due to sharing hardware with other communication technologies, interference with them, heating, etc. However, even in the idle state, the UE capabilities may be affected by the use of other communication technologies (such as WLAN, Bluetooth, etc.), so it is necessary to take this into account for management from the initial RRC connection state. In an embodiment of the present disclosure, even if the UE capabilities temporarily change in the idle state, there is no need to trigger the RRC connection process. Even if the changed UE capabilities are not reported in a state other than the RRC connection state, it does not affect the configuration of the base station. Therefore, the RRC connection process may be triggered only when a general RRC connection is required (when uplink / downlink data occurs). That is, although the temporary change of UE capabilities will not trigger the RRC connection process, if the RRC connection process is triggered due to another reason, it is necessary to determine whether the terminal currently needs a temporary change in UE capabilities, and if the capability change is necessary, the subsequent process reflects the situation.

[0367] In an embodiment of the present disclosure, in order to notify the base station in advance that the UE capability has been temporarily changed in the idle state, the RRC connection process may be triggered even when the RRC connection is not required.

[0368] Generally, if there is a static UE capability that the terminal reports to the base station in the corresponding operation in the previous RRC connection state, the base station can receive the UE capability of the terminal from the CN (UE capability retrieval condition 1), in which case the base station may not request the UE capability of the terminal after the RRC connection process. However, if the base station fails to retrieve the static UE capability of the terminal (UE capability retrieval condition 2), the base station may request and receive the UE capability of the terminal after the RRC connection process. Depending on the above conditions, the operations of the base station and the terminal may be different.

[0369] In operation 1n-10, the terminal 1n-01 sends an RRC recovery request message (msg 3) to the base station 1n-02. In the above operation, msg 3 does not include details of the temporary capability restriction because msg 3 is size sensitive and cannot contain a large amount of information. For example, msg 3 may be a message such as an RRC establishment request, an RRC recovery request, an RRC reconstruction request, etc. In operation 1n-15, the base station 1n-02 sends a retrieval message to 5G CN 1n-03 for determining whether there is context and UE capability information of the terminal stored in 5G CN 1n-03 and requesting the context and UE capability information of the terminal, and receives a response to the retrieval message in operation 1n-20. If the information exists, the base station 1n-02 stores the static UE capabilities.

[0370] In operation 1n-25, the base station 1n-02 sends an RRC recovery message (msg 4) in response to the received RRC recovery request message. The message may include the radio bearer configuration and MCG configuration (RLC bearer, "mac-CellGroupConfig", "physicalCellGroupConfig and spCellConfig", etc.) for SRB 1. The message includes the general configuration of the base station 1n-02 for SRB 1 in this operation, and the terminal 1n-01 receives msg 4 and sends an RRC recovery complete message (msg 5) in response to the configuration of SRB 1 in operation 1n-30. The message may include at least one of a selected PLMN ID, a NAS message, etc., and may include an indicator for temporary capability restriction. The base station 1n-02 can recognize through the indicator that there is a temporary change in UE capabilities and consider this situation in subsequent processes. Based on the content of msg 5 sent from terminal 1n-01, base station 1n-02 can retrieve the static capabilities and context of the terminal from CN, and if there is no corresponding UE capability or if base station 1n-02 fails to retrieve the UE capability, base station 1n-02 can request a report on the UE capability.

[0371] In operation 1n-35, the terminal 1n-01 may request a temporary change of UE capabilities from the base station 1n-02. Information about the temporary change of UE capabilities (i.e., temporary capability restrictions) and a request for a temporary change of UE capabilities may be sent via an RRC message (such as the UE auxiliary information in the above operation). The RRC message may include at least one piece of information that the terminal 1n-01 may request, such as the reason for requesting a temporary change of UE capabilities (e.g., reason value: hardware sharing, interference, overheating, mode change, etc.), frequency bands to be supported and frequency band combination information, changes in the physical functions of the terminal (changes in the number of component carriers, changes in the number of MIMO layers, changes in frequency bands and bandwidth information to be supported by each CC, changes in supported power, changes in frequency ranges to be supported, etc.), etc. The detailed items included in the RRC message and their signaling methods will be described in more detail in another embodiment below. When the terminal reports a change in UE capabilities, if only the UE capabilities that are temporarily changed less than the static UE capabilities are reported, only a subset of the static UE capabilities may always be reported. That is, this is a request for temporarily having some reduced capabilities of the overall static UE capabilities. However, if it is possible to report UE capabilities that temporarily change above the static UE capabilities, then the new UE capabilities that are higher than those reported in the previous static report have to be signaled.

[0372] In addition, a prohibition timer 1n-40 for prohibiting requests to change UE capabilities can be configured to prevent the terminal 1n-01 from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time. If the prohibition timer is not configured, the terminal 1n-01 may frequently send UE capability reports, which makes it difficult for the base station 1n-02 to perform scheduling and management on the terminal. The prohibition timer 1n-40 can be configured to be included in msg 4 during the RRC connection process, and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1n-40 can be configured as a default value according to the internal settings of the terminal, or can be obtained from system information. Although not shown, the base station 1n-02 can send a temporary capability restriction confirmation / rejection message to the terminal 1n-01 in response to the temporary capability restriction request message. If the base station 1n-02 accepts the temporary capability restriction request from the terminal 1n-01, the base station 1m-02 sends a confirmation message to the terminal 1m-01, and if the base station 1n-02 rejects the temporary capability restriction request, the base station 1n-02 sends a rejection message. Both messages can be sent using RRC messages.

[0373] In operation 1n-45, the base station 1n-02 stores or does not reflect the temporary capability limitation information received from the terminal 1n-01 according to whether the temporary capability limitation determined in the operation is reflected. The base station 1n-02 is able to manage the received information only in the access layer (AS) area without sending it to the 5G CN 1n-03. In operation 1n-50, the base station 1n-02 can reflect the temporary capability limitation, thereby sending new RRC configuration information to the terminal 1n-01 through an RRC reconfiguration message. However, if the base station 1n-02 rejects the temporary capability limitation request received from the terminal 1n-01, the base station 1n-02 can omit operation 1n-50 without reflecting the temporary capability limitation, or can configure the RRC reconfiguration based on the original UE capability. That is, the base station 1n-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capability received in the previous operation. The terminal 1n-01 that has received the RRC reconfiguration from the base station 1n-02 in operation 1n-50 transmits information indicating that the RRC reconfiguration has been received to the base station 1n-02 through an RRC reconfiguration complete message for the configuration (operation 1n-55).

[0374] If the terminal 1n-01 needs to release the temporary change of UE capabilities in a state where the temporarily changed UE capabilities are reflected through the above-mentioned process of temporarily changing UE capabilities and the RRC reconfiguration according to the process (operation 1n-60), then in operation 1n-65, the terminal 1n-01 notifies the base station 1n-02 through a temporary capability restriction release message that the temporary change of UE capabilities has been completed and the terminal has returned to the original static UE capabilities. Upon receiving the RRC message, the base station 1n-02 may send a release response RRC message indicating that the corresponding release message has been received to the terminal 1n-01 in operation 1n-70. In operation 1n-75, the base station 1n-02 may determine that the terminal 1n-01 has returned to the static UE capabilities, and may then send a new RRC reconfiguration message to the terminal 1n-01. Alternatively, the release response message in operation 1n-70 may be omitted. That is, if the base station 1n-02 receives the temporary capability restriction release message in operation 1n-65, the base station 1n-02 can send a new RRC reconfiguration message to the terminal 1n-01 without responding to it.

[0375] In addition to the case where the terminal 1n-01 explicitly requests to release the temporary UE capability change as described above, the base station 1n-02 may recognize the temporary capability change of the terminal in the following cases. The following conditions may be simultaneously applied to the terminal 1n-01.

[0376] 1. When the terminal explicitly requests to release the temporary restriction

[0377] 2. The terminal previously indicated a request for a new temporary restriction

[0378] 3. The terminal switches to the RRC idle state or the RRC inactive state.

[0379] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0380] Fig.15 is a diagram illustrating a method in which a terminal in an RRC inactive state requests a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0381] refer to Fig.15, specifically, in the case where the terminal sends relevant information in the process of requesting temporary UE capability restriction in the operation of requesting to switch from an inactive state to a connected state.

[0382] In operation 1o-05, the terminal 1o-01 in the RRC inactive state may have a temporary change in UE capabilities. Generally, when the terminal is in a connected state, the UE capabilities may change due to sharing hardware with other communication technologies, interference with them, heating, etc. However, even in an inactive state, the UE capabilities may be affected by the use of other communication technologies (such as WLAN, Bluetooth, etc.), so it is necessary to take this into account for management from the initial RRC connection state. In an embodiment of the present disclosure, even if the UE capabilities are temporarily changed in an inactive state, there is no need to trigger the RRC recovery process. Even if the changed UE capabilities are not reported in a state other than the RRC connection state, it does not affect the configuration of the base station. Therefore, the RRC recovery process may be triggered only when a general RRC connection is required (when uplink / downlink data occurs). That is, although the temporary change of UE capabilities will not trigger the RRC recovery process, if the RRC recovery process is triggered due to another reason, it is necessary to determine whether the terminal currently needs a temporary change in UE capabilities, and if the capability change is necessary, the subsequent process reflects the situation. In an embodiment of the present disclosure, in order to notify the base station in advance that the UE capability has been temporarily changed in the idle state, the RRC connection process may be triggered even when the RRC connection is not required.

[0383] Generally, if there is a static UE capability that the terminal reports to the base station in the corresponding operation in the previous RRC connection state, the base station can receive the UE capability of the terminal from the CN (UE capability retrieval condition 1), in which case the base station may not request the UE capability of the terminal after the RRC connection process. However, if the base station fails to retrieve the static UE capability of the terminal (UE capability retrieval condition 2), the base station may request and receive the UE capability of the terminal after the RRC connection process. Depending on the above conditions, the operations of the base station and the terminal may be different.

[0384] In operation 1o-10, the terminal 1o-01 sends an RRC recovery request message (msg 3) to the base station 1o-02. In the above operation, msg 3 does not include details of the temporary capability restriction because msg 3 is size sensitive and cannot contain a large amount of information. For example, msg 3 may be a message such as an RRC establishment request, an RRC recovery request, an RRC reconstruction request, etc. In operation 1o-15, the base station 1o-02 sends a retrieval message to 5G CN 1o-03 for determining whether there is context and UE capability information of the terminal stored in 5G CN 1o-03 and requesting the context and UE capability information of the terminal, and receives a response to the retrieval message in operation 1o-20. If the information exists, the base station 1o-02 stores the static UE capabilities.

[0385] In operation 1o-25, the base station 1o-02 sends an RRC recovery message (msg 4) in response to the received RRC recovery request message. The message may include the radio bearer configuration and MCG configuration (RLC bearer, "mac-CellGroupConfig", "physicalCellGroupConfig and spCellConfig", etc.) for SRB 1. The message includes the general configuration of the base station 1o-02 used for SRB 1 in this operation, and the terminal 1o-01 receives msg 4 and sends an RRC recovery completion message (msg 5) to the base station 1o-02 in response to the configuration of SRB 1 in operation 1o-30. The message may include at least one of a selected PLMNID, a NAS message, etc., and may include information about temporary capability restrictions. Based on the content of msg 5 sent from the terminal 1o-01, the base station 1o-02 can retrieve the static capabilities and context of the terminal from the CN, and if there is no corresponding UE capability or if the base station 1o-02 fails to retrieve the UE capability, the base station 1o-02 can request a report on the UE capability.

[0386] Fundamentally, UE capabilities are statically sent to the base station and 5G CN, and if there is no separate signaling, the inherent capabilities of the terminal remain unchanged. However, in the case of an actual terminal, due to the above four reasons and other reasons, it may be necessary to temporarily change the UE capabilities. That is, due to sharing hardware with other communication modules in the terminal, interference with them, temporary heating, changes in terminal mode, etc., temporary changes in UE capabilities that are different from static terminal performance may be generated / needed. Generally, in the case where the UE capabilities are temporarily reduced compared to the static UE capabilities, the terminal needs to report this to the base station to request scheduling and management that complies with the reduced UE capabilities. However, in certain cases, the terminal may have a higher UE capability than the static UE capabilities that the terminal has reported.

[0387] For example, in the case of a foldable terminal, if the performance of the terminal is the static UE capability when the display is folded, the performance of the terminal in the state where the display is unfolded can be configured to be higher. That is, the change in the state of the terminal can make a difference in the performance of the antenna and MIMO applied to the terminal, the power performance of the terminal, etc. In order to support the above situation, in addition to the existing method of reporting UE capabilities, a new signaling structure and its functions are required.

[0388] As described in the above operation 10-30, msg 5 (i.e., RRC recovery completion message) may include at least one piece of information that the terminal 10-01 may request, such as the reason for requesting a temporary change in UE capabilities (e.g., reason value: hardware sharing, interference, overheating, mode change, etc.), the frequency bands to be supported and the frequency band combination information, the change of the physical function of the terminal (the change in the number of component carriers, the change in the number of MIMO layers, the change in the frequency bands and bandwidth information to be supported by each CC, the change in the supported power, the change in the frequency range to be supported, etc.), etc. The detailed items included in the RRC message and their signaling methods will be described in more detail below in another embodiment. When the terminal reports a change in UE capabilities, if only the UE capabilities that are temporarily changed less than the static UE capabilities are reported, only a subset of the static UE capabilities can always be reported. That is, this is a request for temporarily having some reduced capabilities of the overall static UE capabilities. However, if the UE capabilities that are temporarily changed higher than the static UE capabilities can be reported, the new UE capabilities that are higher than the UE capabilities reported in the previous static report must be signaled.

[0389] In addition, a prohibition timer 1o-40 for prohibiting requests to change UE capabilities can be configured to prevent the terminal from repeating or re-requesting temporary capability restrictions within a specific time after requesting temporary capability restrictions using an RRC message, and the application period of the requested UE capabilities can be guaranteed within a specific time. If the prohibition timer is not configured, the terminal 1o-01 may frequently send UE capability reports, which makes it difficult for the base station 1o-02 to perform scheduling and management on the terminal. The prohibition timer 1o-35 can be configured to be included in msg 4 during the RRC connection process and can be included in the RRC reconfiguration message. Alternatively, the prohibition timer 1o-35 can be configured as a default value according to the internal settings of the terminal, or can be obtained from system information. Although not shown, the base station 1o-02 can send a temporary capability restriction confirmation / rejection message to the terminal 1o-01 in response to the temporary capability restriction request message. If the base station 1o-02 accepts the temporary capability restriction request from the terminal 1o-01, the base station 1o-02 sends a confirmation message, and if the base station 1o-02 rejects the temporary capability restriction request, the base station 1o-02 sends a rejection message to the terminal 1o-01. Both messages can be sent using RRC messages.

[0390] In operation 1o-40, the base station 1o-02 stores or does not reflect the temporary capability limitation information received from the terminal 1o-01 according to whether the temporary capability limitation determined in the operation is reflected. The base station 1o-02 manages the received information only in the access layer (AS) area, and does not send it to the 5G CN 1o-03. In operation 1o-45, the base station 1o-02 can reflect the temporary capability limitation, thereby sending new RRC configuration information to the terminal 1o-01 through an RRC reconfiguration message. However, if the base station 1o-02 rejects the temporary capability limitation request received from the terminal 1o-01, the base station 1o-02 can omit operation 1o-45 without reflecting the temporary capability limitation, or can configure the RRC reconfiguration based on the original UE capability. That is, the base station 1o-02 maintains the RRC configuration (RRC reconfiguration) based on the UE capability received in the previous operation. The terminal 1o-01 that has received the RRC reconfiguration from the base station 1o-02 in operation 1o-45 sends information indicating that the RRC reconfiguration has been received to the base station 1o-02 through an RRC reconfiguration complete message for the configuration (operation 1o-50).

[0391] If the terminal 1o-01 needs to release the temporary change of UE capabilities in a state where the temporarily changed UE capabilities are reflected through the above-mentioned process of temporarily changing UE capabilities and the RRC reconfiguration according to the process (operation 1o-55), then in operation 1o-60, the terminal 1o-01 notifies the base station 1o-02 through a temporary capability restriction release message that the temporary change of UE capabilities has been completed and the terminal has returned to the original static UE capabilities. Upon receiving the RRC message, the base station 1o-02 may send a release response RRC message indicating that the corresponding release message has been received to the terminal 1o-01 in operation 1o-65. In operation 1o-70, the base station 1o-02 may determine that the terminal 1o-01 has returned to the static UE capabilities, and may then send a new RRC reconfiguration message to the terminal 1o-01. Alternatively, the release response message in operation 1o-65 may be omitted. That is, if the base station 1o-02 receives a temporary capability restriction release message in operation 1o-60, the base station 1o-02 can send a new RRC reconfiguration message to the terminal 1o-01 without responding to it.

[0392] In addition to the case where the terminal 1o-01 explicitly requests to release the temporary UE capability change as described above, the base station 1o-02 can identify the temporary capability change of the terminal in the following cases. The following conditions can be applied to the terminal 1o-01 at the same time.

[0393] 1. When the terminal explicitly requests to release the temporary restriction

[0394] 2. The terminal previously indicated a request for a new temporary restriction

[0395] 3. The terminal switches to the RRC idle state or the RRC inactive state.

[0396] 4. The case where the retention period of the temporary capability restriction of the terminal is configured by providing a separate timer and the timer expires (the timer can be included in the RRC reconfiguration sent to the terminal. In addition, multiple timers can be configured according to the situation. For example, the timer can be configured to be different according to the cause value of the temporary UE capability restriction, or can be configured to have different values ​​for each terminal in the RRC connected state, idle state and inactive state). If the terminal requests to extend the configured timer value, the terminal can request the timer that is desired to be extended in a manner using UE assistance information, a new RRC message or a MAC CE.

[0397] In the above-mentioned embodiment of the present disclosure, there are two ways for the terminal to request temporary capability restriction. The first method allows msg 3 or msg 5 to include an indicator indicating that temporary capability restriction has occurred, and provides detailed information about the temporary capability restriction through a specific RRC message (e.g., "UEAssistanceInformation" message) in the RRC connection state. The second method is to include detailed information about the temporary capability restriction in msg 3 or msg 5 and provide the information.

[0398] Embodiment 4 of the present disclosure describes in more detail the method in which the terminal includes temporary capability restriction request information as described in Embodiments 1, 2, and 3, and can be applied to all of the above embodiments. Embodiment 4 mainly relates to a method for signaling detailed information about temporary capability restriction using msg 3 and msg 5, and uses a bitmap to process multiple values. That is, if temporary capability restriction is performed by specifying more values ​​using a bitmap, the terminal can dynamically, flexibly, and adaptively request adjustment of the terminal's capabilities according to the network environment, thereby providing the user with the best user experience (UX).

[0399] 1. Use bitmaps to handle multiple values.

[0400] - Only one reason value may appear, but it may appear in duplicate.

[0401] - For example, if the overheating is caused by a disturbance, both must be considered as limiting causes.

[0402] Therefore, the bitmap can be used by methods where multiple reasons can be explicitly transmitted simultaneously.

[0403] - A bitmap may be used to express multiple causes, and scalability for increasing causes may be obtained. The terminal may actively restrict UE capability feature items by mapping UE capability feature items according to cause values ​​using a bitmap.

[0404] 2. Use a bitmap to provide priorities for multiple reason values

[0405] - Priority can be configured by setting additional bits (high 1 / low 0) for desired UE capability features.

[0406] -Since the terminal does know the state of the terminal and its suitable solutions, it is possible to assign priorities to valid solutions.

[0407] - If priorities are configured, the network load for handling throttling can be reduced.

[0408] 3. Add bearer / RAT restrictions.

[0409] - The detached bearer and added bearer items used in EN-DC are also managed using bitmaps.

[0410] This is avoided by limiting the number of RATs in interference-heavy environments.

[0411] - For example, using a bitmap to manage the usage of a specific bearer is useful, as operation as a separate bearer may return to usage in LTE or 5G.

[0412] 4. Use bitmaps to prioritize multiple reduced UE capabilities

[0413] Embodiment 4-1 is Example 1 of a method for processing a request for temporary capability restriction proposed by the present disclosure, and illustrates a method for configuring a cause value of a temporary capability restriction using a bitmap. If the cause value of a temporary capability restriction includes the following four items, a 4-bit bitmap may be configured to indicate the cause value. That is, the bitmap size is equal to the number of cause values.

[0414] 1) Hardware Sharing

[0415] 2) Interference

[0416] 3) Overheating

[0417] 4) Separation of loads

[0418] The initial value may be "0000", or may be represented in the form of a copy according to the corresponding cause value. In the case where overheating occurs due to interference with other communication schemes, the corresponding value may be determined as a value "0110" and transmitted.

[0419] Embodiment 4-2 is Example 2 of a method for processing a request for temporary capability restriction proposed by the present disclosure, and illustrates a method for configuring the cause value and priority of the temporary capability restriction using a bitmap. If the cause value of the temporary UE capability restriction includes the following four items, and if the priority of each cause value is provided, the corresponding cause value and priority can be indicated by configuring an 8-bit bitmap. That is, the bitmap size can be equal to the sum of the number of cause values ​​and the number of priorities. Here, the priority means to determine the cause value with a higher priority among the generated cause values.

[0420] 1) Hardware Sharing

[0421] 2) Interference

[0422] 3) Overheating

[0423] 4) Separation of loads

[0424] 5) Priority #1

[0425] 6) Priority #2

[0426] 7) Priority #3

[0427] 8) Priority #4

[0428] The initial value may be "0000 0000", or may be represented in a duplicate form according to the corresponding cause value. If overheating occurs due to interference with other communication schemes, and if it is determined that overheating has a greater impact among the cause values, that is, if overheating has a higher priority than interference, priority #3 may be determined and transmitted. That is, an 8-bit bitmap "0110 0010" may be set.

[0429] Embodiment 4-3 is Example 3 of the method for processing a request for temporary capability restriction proposed in the present disclosure, and illustrates a method for using a bitmap to configure a list of UE features that are expected to be changed (or reduced) due to temporary capability restrictions. If the list of UE capability features that are required to be changed by the terminal is determined by eight or fewer items, an 8-bit bitmap can be configured and the items selected from the UE capability list requested to be changed can be determined and indicated. That is, the bitmap size can be equal to the number of UE capability lists requested to be changed. If there are the following 8 UE capability lists, the terminal determines and sends the corresponding bits.

[0430] 1) CC quantity

[0431] 2) MIMO layer

[0432] 3) BW

[0433] 4) Power factor

[0434] 5) Loading

[0435] 6) RAT restrictions

[0436] 7) Reserved bits

[0437] 8) Reserved bits

[0438] The initial value may be "0000 0000", or may be represented in the form of a copy according to the corresponding value. In order to indicate a request for changing the bearer and changing the RAT type, an 8-bit bitmap "0000 1100" may be set. In other words, the method is to propose restrictions on the bearer and RAT through UE capability restrictions when a problem occurs in the terminal due to the corresponding signaling, and if the corresponding signaling is provided, a separate signaling is also required for the value changed due to the restriction. That is, there must be a predetermined default value, or the value to be changed due to separate signaling must be indicated. Separate signaling may also be provided in the same message and then may be included in another RRC message for transmission. For example, in the case where MCG and MCG separate bearers are configured as bearer types, separate bearers may be primarily proposed, or another signaling may be used to send a value that explicitly indicates one of the two. Similarly, basic values ​​and explicit signaling may be applied to other items.

[0439] Embodiment 4-4 is Example 4 of the method for processing a request for temporary capability restriction proposed in the present disclosure, and illustrates a method for using a bitmap to configure a list and priority of UE features that are expected to be changed (or reduced) due to temporary capability restrictions. If the list of UE capability features that are required to be changed by the terminal is determined by six or fewer items, and if six priorities corresponding to the features are signaled, a 12-bit bitmap can be configured to determine the item selected from the list of UE capabilities requested to be changed and indicate its priority. That is, the bitmap size can be equal to the sum of the number of UE capability lists and priorities requested to be changed.

[0440] 1) CC quantity

[0441] 2) MIMO layer

[0442] 3) BW

[0443] 4) Power factor

[0444] 5) Loading

[0445] 6) RAT restrictions

[0446] 7) Priority #1

[0447] 8) Priority #2

[0448] 9) Priority #3

[0449] 10) Priority #4

[0450] 11) Priority #5

[0451] 12) Priority #6

[0452] The initial value may be "0000 0000 0000", or may be represented in the form of a copy according to the corresponding value. In order to indicate the change of the bearer and the change of the RAT type, and specifically, to indicate that the bearer control has a higher priority than the RAT type, a 12-bit bitmap "0000 1100 0010" may be set. In other words, the method is to propose the restriction of the bearer and RAT through the UE capability restriction when a problem occurs in the terminal due to the corresponding signaling, and request the control of the bearer with a higher priority. If the corresponding signaling is provided, the signaling for the value changed due to the restriction is also required separately. That is, there must be a predetermined default value, or a separate signaling must be used to indicate the value to be changed. The separate signaling may also be provided in the same message, and then may be included in another RRC message for transmission. For example, in the case where MCG and MCG separate bearers are configured, the separate bearer may be mainly proposed, or another signaling may be used to send a value that explicitly indicates one of the two. Similarly, basic values ​​and explicit signaling may be applied to other items. In addition, the sequence and combination of the values ​​constituting the bitmap may be changed.

[0453] Embodiment 4-5 is Example 5 of the method for processing a request for temporary capability restriction proposed in the present disclosure, and illustrates a method for using a bitmap to configure the cause value of the temporary capability restriction, the list of UE features that are expected to be changed (or reduced), and the priority of the corresponding values. If there are four candidate cause values ​​for the temporary capability restriction of the terminal, if there are four priorities corresponding to these values, if the list of UE capability features required to be changed by the terminal is determined by six or fewer items, and if the six priorities corresponding to these features are signaled, a 20-bit bitmap can be configured to determine the item selected from the cause value and the list of UE capabilities requested to be changed, and indicate its priority. That is, the bitmap size can be equal to the sum of the cause value, the priority of the cause value, the number of UE capability lists requested to be changed, and the priority. The overall bitmap size can be adjusted by adding a reserved value, and the bitmap can be configured as a combination of the aforementioned embodiments.

[0454] 1) Hardware Sharing

[0455] 2) Interference

[0456] 3) Overheating

[0457] 4) Separation of loads

[0458] 5) Priority #1

[0459] 6) Priority #2

[0460] 7) Priority #3

[0461] 8) Priority #4

[0462] 9) CC quantity

[0463] 10) MIMO layer

[0464] 11) BW

[0465] 12) Power Factor

[0466] 13) Loading

[0467] 14) RAT restrictions

[0468] 15) Priority #9

[0469] 16) Priority #10

[0470] 17) Priority #11

[0471] 18) Priority #12

[0472] 19) Priority #13

[0473] 20) Priority #14

[0474] The initial value may be "0000 0000 0000 0000 0000 0000", or may be represented in the form of a copy according to the corresponding value. If the cause value is interference and overheating, and if overheating has a greater impact, in order to indicate the change of the bearer and the change of the RAT type, and specifically, in order to indicate that the bearer control has a higher priority than the RAT type, a 20-bit bitmap "0110 0010 0000 1100 0010" may be set. In other words, the method is to propose restrictions on bearers and RATs through UE capability restrictions when a problem (interference and overheating) occurs in the terminal due to the corresponding signaling (overheating has a greater impact), and request control of the bearer with a higher priority. If the corresponding signaling is provided, signaling for the value changed due to the restriction is also required separately. That is, there must be a predetermined default value, or a separate signaling must be used to indicate the value to be changed. The separate signaling may also be provided in the same message, and then may be included in another RRC message for transmission. For example, in the case where MCG and MCG split bearers are configured as bearer types, split bearers may be primarily proposed, or another signaling may be used to send a value explicitly indicating one of the two. Similarly, basic values ​​and explicit signaling may be applied to other items. In addition, the sequence and combination of values ​​constituting the bitmap may be changed.

[0475] As described above, the changed values ​​of the UE features required by the terminal may be selected and sent via separate signalling rather than a bitmap. This may indicate a subset of static UE capabilities, or may be a value used to request new capabilities.

[0476] Fig.16 2 is a diagram illustrating an overall operation of a terminal in an RRC connected state requesting a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0477] refer to Fig.16 , a terminal in an RRC connected state may have a temporary change in UE capabilities due to an internal problem of the terminal (operation 1p-05). Thereafter, the terminal may generate a message internally by including therein the reason for requesting a change in UE capabilities and the content of the change. The message may be included in msg 3, msg 5 or another RRC message ("UEAssistanceInformation" or a new RRC message), and has been described in detail in the above embodiments. That is, the message may include an indicator for temporary capability restriction or information about the requested temporary capability restriction. In operation 1p-10, the terminal sends a message including the changed content of the terminal to the base station, and operates a prohibition timer to prevent repetition of the request. In operation 1p-15, the terminal receives an RRC reconfiguration message from the base station and reflects the configuration for operation. In this operation, the base station may reflect the temporary capability restriction to provide the temporary capability restriction, or may not reflect the temporary capability restriction, or may omit the operation.

[0478] If the prohibition timer expires in operation 1p-20, then in operation 1p-25, the terminal determines that the terminal has returned to the original UE capabilities and restores the previous configuration. That is, the terminal can return to the configuration before the temporary capability restriction is applied. Alternatively, if there is no separate signaling from the base station, the configuration can be maintained (temporary capability restriction is applied). If the prohibition timer does not expire in operation 1p-20, and if the release of the UE capability change occurs in the terminal in operation 1p-30, then in operation 1p-35, the terminal can send a message to the base station indicating that the UE capability change has been released, and in operation 1p-40, it can be determined that the terminal has returned to the original UE capabilities, thereby restoring the previous configuration. That is, the terminal can return to the configuration before the temporary capability restriction is applied. Alternatively, if there is no separate signaling from the base station, the configuration can be maintained (temporary capability restriction is applied). If it is necessary to maintain the temporary capability restriction without releasing the UE capability change in operation 1p-30, the changed UE capability is maintained (operation 1p-45).

[0479] Fig.17is a diagram illustrating an overall operation of a terminal in an idle or inactive state requesting a temporary change of UE capabilities according to an embodiment of the present disclosure.

[0480] refer to Fig.18 , a terminal in an RRC idle / inactive state may have a temporary change in UE capabilities due to an internal problem of the terminal (operation 1q-05). Thereafter, the terminal may generate a message internally by including therein the reason for requesting a change in UE capabilities and the content of the change. The message may be included in msg 3 or msg 5, or may be included in another RRC message ("UEAssistanceInformation" or a new RRC message) after the RRC connection process is completed, and has been described in detail in the above embodiments. That is, the message may include an indicator for temporary capability restriction or information about the requested temporary capability restriction. In operation 1q-10, the terminal sends a message including the changed content of the terminal to the base station, and operates a prohibition timer to prevent repetition of the request. In operation 1q-15, the terminal switches to a connected state and operates by applying a temporary UE capability change. Although not shown in the figure, the terminal may switch to an RRC connected state, and the corresponding configuration may be applied immediately in the operation. Alternatively, the base station may provide RRC reconfiguration by reflecting the temporary capability restriction thereafter, or may not reflect the temporary capability restriction, or may omit the operation.

[0481] If the prohibition timer expires in operation 1q-20, then in operation 1q-25, the terminal determines that the terminal has returned to the original UE capabilities and restores the previous configuration. That is, the terminal can return to the configuration before the temporary capability restriction is applied. Alternatively, if there is no separate signaling from the base station, the configuration can be maintained (temporary capability restriction is applied). If the prohibition timer does not expire in operation 1q-20, and if the release of the UE capability change occurs in the terminal in operation 1q-30, then in operation 1q-35, the terminal can send a message to the base station indicating that the UE capability change has been released, and in operation 1q-40, it can be determined that the terminal has returned to the original UE capabilities, thereby restoring the previous configuration. That is, the terminal can return to the configuration before the temporary capability restriction is applied. Alternatively, if there is no separate signaling from the base station, the configuration can be maintained (temporary capability restriction is applied). If it is necessary to maintain the temporary capability restriction without releasing the UE capability change in operation 1q-30, the changed UE capability is maintained (operation 1q-45).

[0482] Fig.18 is a diagram illustrating overall operation of a base station receiving a temporary UE capability change of a terminal according to an embodiment of the present disclosure.

[0483] If the base station receives a message requesting a temporary change of UE capabilities from a terminal in any state (RRC connected state, inactive state, or idle state) (operation 1r-05), the base station may determine whether to accept or reject the request message (operation 1r-10). The message may be included in msg 3 or msg 5, or may be included in another RRC message ("UEAssistanceInformation" or a new RRC message) after the RRC connection process is completed, and has been described in detail in the above embodiments. That is, the message may include an indicator for temporary capability restriction or information about the requested temporary capability restriction. If the base station rejects the request message for a temporary change of UE capabilities from the terminal in operation 1r-10 (operation 1r-15), the base station may not provide an RRC reconfiguration reflecting the temporary UE capability change, and may ignore the RRC reconfiguration. Alternatively, the base station may send a rejection message regarding the temporary UE capability change request message of the terminal.

[0484] If the base station accepts the request message for temporary UE capability change from the terminal in operation 1r-10, the base station may provide the terminal with a new RRC reconfiguration reflecting the temporary UE capability change in operation 1r-20. Alternatively, the base station may send a confirmation message indicating acceptance of the temporary UE capability change request message immediately after receiving the temporary UE capability change request message, or may provide a new RRC reconfiguration reflecting the temporary UE capability change after sending the confirmation message. If the base station receives a request message for releasing the temporary UE capability change from the terminal in operation 1r-25 (this may also apply to the expiration of the configured prohibition timer), the base station may determine that the terminal has returned to the original configuration and may manage the terminal according to the previous configuration, or may retransmit the RRC reconfiguration for the original configuration in operation 1r-30. Similarly, in the above operation, the base station may send a confirmation message indicating acceptance of the temporary UE capability change release request message immediately after receiving the temporary UE capability change release request message, or may provide a new RRC reconfiguration reflecting the temporary UE capability change after sending the confirmation message. If in operation 1r-25 the base station does not receive a request message from the terminal for releasing the temporary UE capability change (this may also apply to the expiration of the configured prohibition timer), the base station determines that the terminal maintains the changed UE capabilities and manages the terminal by maintaining the RRC reconfiguration value reflecting the temporary UE capability change (operation 1r-35).

[0485] Fig.19 is a diagram showing a configuration of a terminal according to an embodiment of the present disclosure.

[0486] refer to Fig.19, the terminal according to the embodiment includes a transceiver 1s-05, a controller 1s-10, a multiplexer / demultiplexer 1s-15, various upper layer processors 1s-20 and 1s-25, and a control message processor 1s-30.

[0487] The transceiver 1s-05 receives data and predetermined control signals through the forward channel of the service cell, and sends data and predetermined control signals through its reverse channel. In the case where multiple service cells are configured, the transceiver 1s-05 performs transmission and reception of data and control signals through the multiple service cells. The multiplexer / demultiplexer 1s-15 multiplexes data generated by the upper layer processors 1s-20 and 1s-25 or the control message processor 1s-30, or demultiplexes data received by the transceiver 1s-05, thereby sending it to the appropriate upper layer processor 1s-20 or 1s-25 or the control message processor 1s-30.

[0488] The control message processor 1s-30 sends control messages to and receives control messages from the base station, thereby performing necessary operations. These operations include processing control messages such as RRC messages and MAC CE, reporting channel occupancy rate (CBR) measurements, and receiving RRC messages for resource pool and terminal operations. The upper layer processors 1s-20 and 1s-25 represent DRB devices and can be configured for each service. The upper layer processors 1s-20 and 1s-25 process data generated from user services such as file transfer protocol (FTP) or Internet voice (VoIP) and send it to the multiplexer / demultiplexer 1s-15, or process data sent from the multiplexer / demultiplexer 1s-15 and send it to the upper layer service application. The controller 1s-10 identifies a scheduling command (e.g., a reverse grant) received by the transceiver 1s-05, and controls the transceiver 1s-05 and the multiplexer / demultiplexer 1s-15 so that reverse transmission is performed at the appropriate time through the appropriate transmission resources.

[0489] Meanwhile, although the above embodiment describes that the terminal includes a plurality of blocks and each block performs a different function, this is merely an example, and the present disclosure is not limited thereto. For example, the controller 1s-10 may perform the function performed by the multiplexer / demultiplexer 1s-15. The controller 1s-10 may include at least one processor. According to an embodiment, the controller 1s-10 may control the operation of the terminal.

[0490] Fig. 20 is a diagram showing a configuration of a base station according to an embodiment of the present disclosure.

[0491] refer to Fig. 20The base station includes a transceiver 1t-05, a controller 1t-10, a multiplexer / demultiplexer 1t-20, a control message processor 1t-35, various upper layer processors 1t-25 and 1t-30, and a scheduler 1t-15.

[0492] The transceiver 1t-05 transmits data and predetermined control signals through a forward carrier wave, and receives data and predetermined control signals through a reverse carrier wave. When multiple carrier waves are configured, the transceiver 1t-05 performs transmission and reception of data and control signals through multiple carrier waves. The multiplexer / demultiplexer 1t-20 multiplexes data generated by the upper layer processors 1t-25 and 1t-30 or the control message processor 1t-35, or demultiplexes data received by the transceiver 1t-05, thereby transmitting it to the appropriate upper layer processor 1t-25 or 1t-30, the control message processor 1t-35 or the controller 1t-10.

[0493] The control message processor 1t-35 generates a message to be sent to the terminal under the control of the controller and sends the message to the lower layer. The upper layer processors 1t-25 and 1t-30 can be configured for each terminal and each service. The upper layer processors 1t-25 and 1t-30 process data generated from user services such as FTP or VoIP and send it to the multiplexer / demultiplexer 1t-20, or process data sent from the multiplexer / demultiplexer 1t-20 and send it to the upper layer service application. The scheduler 1t-15 considers the buffer status, channel status, active time of the terminal, etc. of the terminal, allocates transmission resources to the terminal at the appropriate time, and allows the transceiver to process the signal sent from the terminal or send the signal to the terminal. The controller 1t-10 may include at least one processor. According to an embodiment, the controller 1t-10 can control the operation of the base station.

[0494] In the above detailed embodiments of the present disclosure, the components included in the present disclosure are expressed in the singular or plural, depending on the detailed embodiments presented. However, the singular or plural form is selected for the convenience of describing the situation suitable for presentation, and the various embodiments of the present disclosure are not limited to its single element or multiple elements. In addition, multiple elements expressed in the description can be configured as a single element, or a single element in the description can be configured as multiple elements.

[0495] While the present disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: identifying whether information of a reason for requesting restriction of capabilities of the terminal is detected; In the case where the cause information is detected, reporting a first message including auxiliary information about the change of the capability of the terminal and the detected cause information to the base station, The auxiliary information includes information about at least one of the number of component carriers supported by the terminal, the bandwidth supported by the terminal, and the number of multiple-input multiple-output MIMO layers supported by the terminal; receiving, from the base station, a second message as a response to the first message, the second message including first information for limiting the capability of the terminal and second information on a timer for maintaining the limited capability of the terminal; and performing communication with the base station based on the restricted capabilities of the terminal during a period configured by the value of the timer, wherein the restricted capabilities of the terminal are released based on the expiration of the timer, wherein the detected cause information indicates one of a first problem for sharing hardware with other communication methods, a second problem for interference caused by other communication methods, a third problem for abnormal operation of the terminal, and a fourth problem for change of terminal mode, and Among them, the value of the timer is determined differently based on which of the first problem, the second problem, the third problem and the fourth problem is indicated by the detected cause information, and the state of the terminal which is one of the wireless resource control RRC connection state, RRC inactive state and RRC idle state.

2. The method according to claim 1, further comprising: receiving information about a prohibit timer for assistance information reporting from a base station, wherein the first message is reported without the inhibit timer running, and The prohibition timer starts after the first message is reported.

3. The method according to claim 1, further comprising: receiving a user equipment UE capability query from a base station; The UE capability information based on the UE capability query is sent to the base station.

4. A method performed by a base station in a wireless communication system, the method comprising: receiving, from the terminal, a first message including auxiliary information and cause information regarding a change in capability of the terminal based on the cause information, The auxiliary information includes information about at least one of the number of component carriers supported by the terminal, the bandwidth supported by the terminal, and the number of multiple-input multiple-output MIMO layers supported by the terminal; transmitting, as a response to the first message, to the terminal, a second message including first information for limiting the capability of the terminal and second information on a timer for maintaining the limited capability of the terminal; and performing communications with the terminal based on the restricted capabilities of the terminal during a period configured by the value of the timer, wherein the restricted capabilities of the terminal are released based on the expiration of the timer, wherein the cause information indicates one of a first problem for sharing hardware with other communication methods, a second problem for interference caused by other communication methods, a third problem for abnormal operation of the terminal, and a fourth problem for change of terminal mode, and Among them, the value of the timer is determined differently based on which of the first problem, the second problem, the third problem and the fourth problem is indicated by the cause information, and the state of the terminal which is one of the radio resource control RRC connection state, RRC inactive state and RRC idle state.

5. The method according to claim 4, sending information about a prohibit timer for assistance information reporting to the terminal, in, The first message is received without an inhibit timer running in the terminal, and The prohibition timer is started by the terminal after the first message is sent.

6. The method according to claim 4, further comprising: Sending a user equipment UE capability query to the terminal; UE capability information based on the UE capability query is received from the terminal.

7. A terminal in a wireless communication system, the terminal comprising: Transceiver; and At least one processor configured to: Identifying whether information of the reason for requesting limitation of the capabilities of the terminal is detected, In a case where the cause information is detected, reporting a first message including auxiliary information about a change in capability of the terminal and the detected cause information to the base station via the transceiver, The auxiliary information includes information about at least one of the number of component carriers supported by the terminal, the bandwidth supported by the terminal, and the number of multiple-input multiple-output MIMO layers supported by the terminal; receiving, via the transceiver, from the base station a second message as a response to the first message, the second message including first information for limiting the capability of the terminal and second information on a timer for maintaining the limited capability of the terminal; and performing communication with the base station based on the restricted capabilities of the terminal during a period configured by the value of the timer, wherein the restricted capabilities of the terminal are released based on the expiration of the timer, wherein the detected cause information indicates one of a first problem for sharing hardware with other communication methods, a second problem for interference caused by other communication methods, a third problem for abnormal operation of the terminal, and a fourth problem for change of terminal mode, and Among them, the value of the timer is determined differently based on which of the first problem, the second problem, the third problem and the fourth problem is indicated by the detected cause information, and the state of the terminal which is one of the wireless resource control RRC connection state, RRC inactive state and RRC idle state.

8. The terminal according to claim 7, in, The at least one processor is further configured to receive information about a prohibit timer for assistance information reporting from a base station via the transceiver, wherein the first message is reported without the inhibit timer running, and Wherein, the at least one processor is further configured to start a prohibit timer after the first message is reported.

9. The terminal according to claim 7, wherein: The at least one processor is further configured to: receiving a user equipment UE capability query from a base station via a transceiver, The UE capability information based on the UE capability query is sent to the base station via the transceiver.

10. A base station in a wireless communication system, the base station comprising: Transceiver; and At least one processor configured to: receiving, via the transceiver, from a terminal a first message including auxiliary information about a change in capability of the terminal based on cause information and cause information, wherein the auxiliary information includes information about at least one of the number of component carriers supported by the terminal, the bandwidth supported by the terminal, and the number of multiple-input multiple-output (MIMO) layers supported by the terminal, sending, via the transceiver, to the terminal a second message as a response to the first message, the second message including first information for limiting the capability of the terminal and second information on a timer for maintaining the limited capability of the terminal, and performing communications with the terminal based on the restricted capabilities of the terminal during a period configured by the value of the timer, wherein the restricted capabilities of the terminal are released based on the expiration of the timer, wherein the cause information indicates one of a first problem for sharing hardware with other communication methods, a second problem for interference caused by other communication methods, a third problem for abnormal operation of the terminal, and a fourth problem for change of terminal mode, and Among them, the value of the timer is determined differently based on which of the first problem, the second problem, the third problem and the fourth problem is indicated by the cause information, and the state of the terminal which is one of the radio resource control RRC connection state, RRC inactive state and RRC idle state.

11. The base station according to claim 10, in, The at least one processor is further configured to send information about a prohibit timer for assistance information reporting to the terminal via the transceiver, wherein the first message is received when an inhibit timer is not running in the terminal, and The prohibition timer is started by the terminal after the first message is sent.

12. The base station according to claim 10, wherein: The at least one processor is further configured to: sending a user equipment UE capability query to the terminal via the transceiver, and UE capability information based on the UE capability query is received from the terminal via the transceiver.

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