Method and apparatus for optimizing non-public network (NPN) in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. A method performed by a user equipment (UE) in a wireless communication system, the method comprising: receiving logged minimization of drive test (MDT) configuration information comprising a list of at least one non-public network (NPN) identity; performing the logged MDT on the independent NPN (SNPN) based on the logged MDT configuration information; identifying whether the identification of the SNPN selected or registered by the UE matches the list; transmitting, to a base station (BS), an availability indicator indicating that a result of the logged MDT is stored in the UE, if the identification of the SNPN selected or registered by the UE matches the list; receiving a UE information request message from the BS; and transmitting a UE information response message including the result of the logged MDT of the SNPN to the BS in response to the UE information request message.

Description

Technical Field

[0001] The present disclosure relates to terminal and base station operations in a wireless communication system, and in particular to a method and apparatus for optimizing a non-public network (NPN). Background Art

[0002] The fifth generation (5G) mobile communication technology defines a wide frequency band, making high transmission rates and new services possible, and can be implemented not only in "sub-6Ghz" frequency bands such as 3.5Ghz, but also in "above 6Ghz" frequency bands (including 28Ghz and 39GHz) called millimeter waves. In addition, it has been considered to implement 6G mobile communication technology (called super 5G system) in terahertz (THz) frequency bands (e.g., 95GHz to 3THz frequency bands) in order to achieve a transmission rate fifty times faster than that of 5G mobile communication technology and an ultra-low latency that is one-tenth of that of 5G mobile communication technology.

[0003] At the beginning of the development of 5G mobile communication technology, in order to support services and meet the performance requirements related to enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC) and massive machine type communication (mMTC), standardization on beamforming and massive MIMO is underway to reduce radio wave path loss in millimeter waves and increase radio wave transmission distance, thereby supporting parameter sets for dynamic operation of millimeter wave resources and time slot formats for efficient utilization (for example, operating multiple subcarrier spacings), initial access technology for supporting multi-beam transmission and broadband, definition and operation of BWP (bandwidth part), new channel coding methods (such as LDPC (low-density parity check) codes for large amounts of data transmission and polarization codes for high-reliability transmission of control information), L2 preprocessing, and network slicing for providing dedicated networks dedicated to specific services.

[0004] Currently, in view of the services supported by 5G mobile communication technology, discussions on the improvement and performance enhancement of initial 5G mobile communication technology are underway, and there is already physical layer standardization on the following technologies, for example, V2X (Vehicle-to-Everything) for assisting driving decisions by autonomous vehicles based on information about the location and status of the vehicle transmitted by the vehicle and for improving user convenience, NR-U (New Radio Unlicensed) for system operation designed to comply with various regulatory requirements in unlicensed bands, NR UE energy saving, and non-terrestrial network (NTN) for UE-satellite direct communication for providing coverage and positioning in areas where terrestrial network communications are not available.

[0005] In addition, the air interface architecture / protocols for the following technologies are being standardized, such as the Industrial Internet of Things (IIoT) for supporting new services through interworking and integration with other industries, IAB (Integrated Access and Backhaul) for providing nodes for network service area extension by supporting wireless backhaul links and access links in an integrated manner, mobility enhancement including conditional switching and DAPS (Dual Active Protocol Stack) switching, and two-step random access (2-step RACH for NR) for simplifying the random access process. The system architecture / services for the following technologies are also being standardized: 5G baseline architecture (e.g., service-based architecture or service-based interface) for combining network function virtualization (NFV) and software defined network (SDN) technologies, and mobile edge computing (MEC) for receiving services based on UE location.

[0006] With the commercialization of 5G mobile communication systems, the number of connected devices, which has been growing exponentially, will be connected to the communication network, and it is therefore expected that there will be a need to enhance the functions and performance of the 5G mobile communication systems and the integrated operations of the connected devices. To this end, new research is planned related to the following technologies: Extended Reality (XR) for effectively supporting AR (Augmented Reality), VR (Virtual Reality), MR (Mixed Reality), etc., as well as 5G performance improvement and complexity reduction by utilizing artificial intelligence (AI) and machine learning (ML), AI service support, virtual world service support, and drone communication.

[0007] In addition, such developments in 5G mobile communication systems will serve as a foundation for developing new waveforms for providing coverage in the terahertz band for 6G mobile communication technology, multi-antenna transmission technologies such as full-dimensional MIMO (FD-MIMO), array antennas, and large antennas, metamaterial-based lenses and antennas for improving the coverage of terahertz band signals, high-dimensional spatial multiplexing technology using OAM (orbital angular momentum), RIS (reconfigurable smart surface), full-duplex technology for increasing the frequency efficiency of 6G mobile communication technology and improving system networks, AI-based communication technology for achieving system optimization by utilizing satellites and AI (artificial intelligence) from the design stage and internalizing end-to-end AI support functions, and next-generation distributed computing technology for implementing services at a complexity level that exceeds the limits of UE operating capabilities by utilizing ultra-high-performance communication and computing resources. Summary of the invention

[0008] Technical issues

[0009] As described above, with the advancement of mobile communication systems, various services can be provided, and a solution for efficiently providing such services is required, and in particular, a solution for optimizing a non-public network (NPN) is required.

[0010] Solution to the problem

[0011] The disclosed embodiments provide an apparatus and method for efficiently providing services in a wireless communication system.

[0012] According to an embodiment of the present disclosure, a method performed by a user equipment (UE) in a wireless communication system includes: receiving logged minimization of drive tests (MDT) configuration information including a list of at least one non-public network (NPN) identifier; performing logged MDT on a standalone NPN (SNPN) based on the logged MDT configuration information; identifying whether the identifier of the SNPN selected or registered by the UE matches the list; in a case where the identifier of the SNPN selected or registered by the UE matches the list, transmitting an availability indicator to a base station (BS), the availability indicator indicating that the result of the logged MDT is stored in the UE; receiving a UE information request message from the BS; and transmitting a UE information response message including the result of the logged MDT for the SNPN to the BS as a response to the UE information request message.

[0013] The present disclosure provides an apparatus and method for efficiently providing a service in a wireless communication system.

[0014] Before proceeding to the following detailed description, it may be helpful to set forth definitions of certain words and phrases used throughout this patent document: the terms "include" and "comprising" and their derivatives mean including, but not limited to; the term "or" is inclusive, meaning and / or; the phrases "associated with" and "associated with" and their derivatives may mean including, included within, interconnected with, containing, contained within, connected to or connected with, coupled to or coupled with, capable of communicating with, cooperating with, interleaved, juxtaposed, proximate to, bound to or bound with, having, having the property of, and the like; and the term "controller" means any device, system, or portion thereof that controls at least one operation, such device may be implemented in hardware, firmware, or software, or some combination of at least two thereof. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether local or remote.

[0015] In addition, the various functions described below can be implemented or supported by one or more computer programs, each of which is formed by a computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, processes, functions, objects, classifications, instances, related data or a portion thereof suitable for implementation with a suitable computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as a read-only memory (ROM), a random access memory (RAM), a hard drive, a compact disk (CD), a digital video disc (DVD) or any other type of memory. "Non-transitory" computer-readable media excludes wired, wireless, optical or other communication links that transmit instantaneous electrical signals or other signals. Non-transitory computer-readable media include media that can permanently store data, and media that can store data and then rewrite data, such as rewritable optical disks or erasable memory devices.

[0016] Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:

[0018] Figure 1A The structure of a next generation mobile communication system according to an embodiment of the present disclosure is shown;

[0019] Figure 1B shows a radio access state transition in a next generation mobile communication system according to an embodiment of the present disclosure;

[0020] Figure 1C A technique for collecting and reporting cell measurement information according to an embodiment of the present disclosure is shown;

[0021] Figure 1D A method for collecting and reporting cell measurement information according to an embodiment of the present disclosure is shown;

[0022] Figure 1E A flowchart illustrating operations for collecting and reporting cell measurement information according to an embodiment of the present disclosure is shown;

[0023] Figure 1F illustrates a visited separate non-public network (V-SNPN) according to an embodiment of the present disclosure;

[0024] Figure 1G shows data loading (O)-SNPN according to an embodiment of the present disclosure;

[0025] Figure 1H A flowchart showing operations of collecting and reporting NPN related information through logged minimization of drive tests (MDT) according to an embodiment of the present disclosure;

[0026] Fig. 1I A flowchart showing terminal operations for collecting and reporting NPN related information via logged MDT according to an embodiment of the present disclosure is shown;

[0027] Figure 1J A flowchart showing a base station operation for collecting and reporting NPN related information via logged MDT according to an embodiment of the present disclosure;

[0028] Figure 1K A flowchart illustrating operations of collecting and reporting NPN related information through a charging enabling function (CEF) report according to an embodiment of the present disclosure;

[0029] Figure 1L A flowchart of terminal operations for collecting and reporting NPN related information through CEF reporting according to an embodiment of the present disclosure is shown;

[0030] Figure 1M A flowchart illustrating operations for collecting and reporting NPN related information through a radio link failure (RLF) report according to an embodiment of the present disclosure;

[0031] Figure 1N A flowchart of terminal operations for collecting and reporting NPN related information through RLF reporting according to an embodiment of the present disclosure is shown;

[0032] Fig.1O shows the internal structure of a terminal according to an embodiment of the present disclosure; and

[0033] Figure 1P The configuration of a base station according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0034] The following patent document discusses Figure 1A to Figure 1P The various embodiments used to describe the principles of the present disclosure are for illustration only and should not be interpreted in any way as limiting the scope of the present disclosure. Those skilled in the art will appreciate that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0035] Hereinafter, when describing the present disclosure, if it is considered that the detailed description of the relevant known functions or configurations unnecessarily obscures the subject matter of the present disclosure, their detailed description will be omitted. The terms to be described below are defined by considering the functions in the present disclosure and may differ according to the intention or practice of the user or operator. Therefore, they should be defined based on the contents of the entire specification. Hereinafter, embodiments of the present disclosure are described in detail with reference to the accompanying drawings.

[0036] The advantages and features of the present disclosure and methods for achieving them will become apparent with reference to the embodiments described in detail below in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below, but can be implemented in various different forms, which are provided not only to make the scope of the present disclosure comprehensive but also to allow those skilled in the art to fully understand the category of the present disclosure, and the present disclosure is limited only to the scope of the claims. Throughout the specification, the same reference numerals refer to the same elements.

[0037] At this point, it should be understood that each block of the process flow diagram and the combination of the flow diagram can be executed by computer program instructions. Since these computer program instructions can be installed on a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, the instructions executed by the processor of the computer or other programmable data processing device can produce a device for performing the functions described in the flow chart box. Because these computer program instructions can also be stored in a computer-usable or computer-readable memory, which can instruct the computer or other programmable data processing device to operate in a specific manner, the instructions stored in the computer-usable or computer-readable memory can produce a product including an instruction device for implementing the functions described in the flow chart box. Because the computer program instructions can also be loaded on a computer or other programmable data processing device, a series of operating steps can be executed on a computer or other programmable data processing device to produce a computer executable process, and thus the instructions of the computer or other programmable data processing device can provide steps for performing the functions described in the flow chart box.

[0038] In addition, each box can represent a part of a module, section or code, which includes one or more executable instructions for implementing a specified logical function. In addition, it should be noted that in some alternative implementations, the functions mentioned in the box can occur out of order. For example, two boxes shown in succession can actually be executed substantially simultaneously, or boxes can sometimes be executed in reverse order, depending on the corresponding functionality.

[0039] At this time, the term "~ unit" used in the present embodiment indicates a software component or hardware component such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), and the "~ unit" performs a specific role. However, the "~ unit" is not limited to software or hardware. The "~ unit" can be configured to reside on an addressable storage medium and is configured to be reproduced on one or more processors. Therefore, the "~ unit" may include, for example, components (such as software components, object-oriented software components, class components and task components), processes, functions, attributes, procedures, subroutines, program code fragments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays and variables. The functionality provided in the components and "~ units" can be combined into fewer components and "~ units", or can be further divided into other components and "~ units". In addition, the components and "~ units" can be implemented as one or more central processing units (CPUs) in a reproduction device or a secure multimedia card. In addition, the "~ unit" in the embodiment may include one or more processors.

[0040] In the following description of the present disclosure, if it is considered that detailed descriptions of well-known functions or elements associated with the present disclosure will unnecessarily obscure the subject matter of the present disclosure, such detailed descriptions will be omitted. Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0041] For the convenience of description, only the terms used to identify access nodes, the terms indicating network entities, the terms indicating messages, the terms indicating interfaces between network entities, and the terms indicating various pieces of identification information used in the following description are shown. Therefore, the present disclosure is not limited to the terms to be described, and other terms with the same technical meaning may be used.

[0042] In the following description, physical channels and signals may be used interchangeably with data or control signals. For example, a physical downlink shared channel (PDSCH) indicates a physical channel that carries data, but PDSCH may also be used to indicate data. That is, in the present disclosure, the expression "transmitting a physical channel" may be equally interpreted as indicating "transmitting data or a signal through a physical channel".

[0043] Hereinafter, in the present disclosure, high-layer signaling indicates a signal transmission method transmitted from a base station to a terminal using a downlink data channel of a physical layer or transmitted from a terminal to a base station using an uplink data channel of a physical layer. High-layer signaling can be understood as radio resource control (RRC) signaling or medium access control (MAC) control element (CE).

[0044] In the following, for ease of description, the present disclosure adopts the terms and names defined in the 3rd Generation Partnership Project (3GPP) New Radio (NR) or 3GPP Long Term Evolution (LTE) standards. However, the present disclosure is not limited to such terms and names, and may be equally applied to systems conforming to other standards. In the present disclosure, next generation Node B (gNB) may be used interchangeably with evolved Node B (eNB). That is, a base station described as an eNB may indicate a gNB. In addition, the term "terminal" may indicate not only cellular phones, machine type communication (MTC) devices, narrowband (NB) Internet of Things (IoT) devices, and sensors, but also other wireless communication devices.

[0045] In the following, a base station as an entity for performing resource allocation of a terminal may be at least one of a gNB, an eNB, a Node B, a base station (BS), a radio access unit, a base station controller, or a node on 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 for performing a communication function. It is worth noting that the present disclosure is not limited to those examples.

[0046] Specifically, the present disclosure may be applied to 3GPP NR (fifth generation (5G) mobile communication standard). The present disclosure may be applied to smart services based on 5G communication and IoT-related technologies (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail, security and safety services, etc.). In the present disclosure, for ease of explanation, eNB may be used interchangeably with gNB. That is, a base station described as an eNB may indicate a gNB. In addition, the term "terminal" may indicate other wireless communication devices as well as mobile phones, NB-IoT devices, and sensors.

[0047] Wireless communication systems are evolving from their early voice-oriented service systems to, for example, broadband wireless communication systems that provide high-speed, high-quality packet data services according to communication standards such as 3GPP's High Speed ​​Packet Access (HSPA), LTE or Evolved Universal Terrestrial Radio Access (E-UTRA), Advanced LTE (A), LTE-Pro, 3GPP2's High Rate Packet Data (HRPD), Ultra Mobile Broadband (UMB), and Institute of Electrical and Electronics Engineers (IEEE) 802.16e.

[0048] As a representative example of a broadband wireless communication system, the LTE system adopts an orthogonal frequency division multiplexing (OFDM) scheme in a downlink (DL) and a single carrier frequency division multiple access (SC-FDMA) scheme in an uplink (UL). UL indicates a radio link through which a UE or MS transmits data or a control signal to an eNB or a BS, and DL indicates a radio link through which an eNB transmits data or a control signal to a UE. The multiple access scheme distinguishes the data or control information of each user by assigning and operating time-frequency resources for carrying the data or control information of each user so as not to overlap, that is, to establish orthogonality.

[0049] The future communication system after LTE (i.e., 5G communication system) which should be able to freely reflect the various needs of users and service providers needs to support services for simultaneously meeting various needs. The services considered by the 5G communication system include enhanced mobile broadband (eMBB), massive MTC (mMTC), ultra-reliable low-latency communication (URLLC), etc.

[0050] According to an embodiment, eMBB is intended to provide a faster data rate than the data rate supported by existing LTE, LTE-A or LTE-Pro. For example, for one base station, the eMBB in the 5G communication system should be able to provide a peak data rate of 20 gigabits per second (Gbps) in DL and a peak data rate of 10Gbps in UL. In addition, the 5G communication system should provide a peak data rate and simultaneously provide an increased user-perceived data rate of the terminal. In order to meet these requirements, it is necessary to improve various transmission and reception technologies, including more advanced multiple-input multiple-output (MIMO) transmission technologies. In addition, when a maximum of 20 megahertz (MHz) transmission bandwidth is used to transmit a signal in the 2GHz band used by LTE, the 5G communication system uses a frequency bandwidth wider than 20MHz in a band of 3GHz to 6GHz or 6GHz or higher, thereby meeting the required data rate in the 5G communication system.

[0051] At the same time, the 5G communication system is regarded as mMTC to support application services such as IoT. mMTC requires large-scale terminal access support in the cell, terminal coverage enhancement, improved battery time, and terminal cost reduction in order to effectively provide IoT. IoT is attached to various sensors and various devices to provide communication functions, and therefore should be able to support a large number of terminals in the cell (e.g., 1,000,000 terminals / km2). In addition, terminals supporting mMTC are likely to be located in shadow areas not covered by the cell, such as the basement of a building, due to their service characteristics, and therefore may require a wider coverage than other services provided by the 5G communication system. Terminals supporting mMTC should be configured with low-priced terminals and may require a fairly long battery life, such as 10 to 15 years, because the battery of the terminal is difficult to replace frequently.

[0052] Finally, URLLC is a cellular-based wireless communication service for mission-critical purposes, and can be used for remote control of robots or mechanical devices, industrial automation, unmanned aerial vehicles, remote health care, emergency notifications, etc. Therefore, the communication provided by URLLC should provide very low latency (ultra-low latency) and very high reliability (ultra-high reliability). For example, services supporting URLLC should meet the requirements of an air interface delay of less than 0.5 milliseconds and a packet error rate of less than 10-5. Therefore, for services supporting URLLC, the 5G system should provide a smaller transmission time interval (TTI) than other services, and at the same time, it is necessary to allocate wider resources in the frequency band to obtain design issues for communication link reliability.

[0053] The three services of the 5G communication system (ie, eMBB, URLLC, and mMTC) can be multiplexed and transmitted in one system. In this case, in order to meet the different needs of the corresponding services, different transmission and reception schemes and transmission and reception parameters can be used between services. It is worth noting that the aforementioned mMTC, URLLC, and URLLC 5G are merely examples of different service types, and the service types according to the present disclosure are not limited to these examples.

[0054] In addition, LTE, LTE-A, LTE Pro or 5G (or NR or next generation mobile communication) are used as examples to explain the embodiments of the present disclosure, but the embodiments of the present disclosure can be applied to other communication systems with similar technical backgrounds or channel forms. In addition, based on the determination of those skilled in the art, the present disclosure can also be applied to other communication systems with some modifications without significantly departing from the scope of the present disclosure.

[0055] Figure 1A A structure of a next generation mobile communication system according to an embodiment of the present disclosure is shown.

[0056] refer to Figure 1A , the radio access network of the next generation communication system (NR) may include but is not limited to NR Node B (gNB) 1a-10 and NR core network, and the NR core network may include but is not limited to Figure 1A Access Management Function (AMF) 1a-05 is shown. NR UE or UE 1a-15 can access external networks via gNB 1a-10 and AMF 1a-05.

[0057] exist Figure 1A In the figure, gNB 1a-10 may correspond to the eNB of the existing LTE system. gNB 1a-10 is connected to NR UE 1a-15 through a radio channel and may provide more advanced services than the existing Node B (LTE base station), as shown in 1a-20. Since each user service is served by a shared channel in the next generation mobile communication system, a device is required for collecting UE status information (such as buffer status, available transmit power status, and channel status) and performing scheduling, which may be managed by gNB 1a-10. One gNB may typically control multiple cells. In order to achieve ultra-high-speed data transmission compared to the existing LTE system, the next generation mobile communication system may have a maximum bandwidth greater than the existing maximum bandwidth, and may adopt beamforming technology as a radio access technology in addition to OFDM.

[0058] According to an embodiment of the present disclosure, gNB 1a-10 may apply adaptive modulation and coding (AMC), which determines a modulation scheme and a channel coding rate based on a UE channel state.

[0059] According to an embodiment of the present disclosure, AMF 1a-05 can perform functions such as mobility support, bearer setting, quality of service (QoS) setting, etc. AMF 1a-05 manages various control functions and mobility management functions of UE, and can be connected to multiple gNBs. The next-generation mobile communication system can also cooperate with the existing LTE system, and AMF 1a-05 can be connected to the mobility management entity (MME) 1a-25 through a network interface. MME 1a-25 can be connected to eNB 1a-30 which is an existing base station. A UE supporting LTE-NR dual connection can transmit and receive data while maintaining connection with eNB 1a-30 and gNB 1a-10, as shown in 1a-35.

[0060] Figure 1B A radio access state transition in a next generation mobile communication system according to an embodiment of the present disclosure is shown.

[0061] The next generation mobile communication system has three RRC states. The connected mode RRC CONNECTED 1b-05 can be an RRC state in which the UE can transmit and receive data. The idle mode RRC IDLE 1b-30 can be an RRC state in which the UE monitors whether paging is transmitted to the UE. The connected mode 1b-05 and the idle mode 1b-30 are RRC states applied to the existing LTE system, and their detailed descriptions are the same as those of the existing LTE system. The next generation mobile communication system defines the inactive mode RRC INACTIVE1b-15 as a new RRC state. In the inactive mode 1b-15RRC state, the UE context is maintained in the gNB and the UE, and paging based on the radio access network (RAN) can be supported. The characteristics of the inactive RRC state are described as follows, but are not limited to:

[0062] -Cell reselection mobility;

[0063] - A CN-NR RAN connection (both C / U plane) has been established for the UE;

[0064] -UE AS context is stored in at least one gNB and the UE;

[0065] -Paging is initiated by NR RAN;

[0066] - the RAN based notification area is managed by the NR RAN; and / or

[0067] - The NR RAN is aware of the RAN based notification area to which the UE belongs.

[0068] According to an embodiment of the present invention, the inactive mode 1b-15 RRC state can be switched to the connected mode or the idle mode through a specific process. The transition from the inactive mode 1b-15 to the connected mode 1-05 can be performed according to the RRC recovery process, and the transition from the connected mode 1b-05 to the inactive mode 1b-15 can be performed by using a release process including the suspension configuration information, as shown in 1b-10. The above process may include a process for transmitting and receiving one or more RRC messages between the UE and the gNB, and may include one or more steps. The transition from the inactive mode 1b-15 to the idle mode 1b-30 can be performed through the release process 1b-20 after the RRC recovery. The transition between the connected mode and the idle mode can comply with the existing LTE technology. That is, the transition between the RRC states (three modes) can be performed by establishing or releasing the process 1b-25.

[0069] Figure 1C A technique for collecting and reporting cell measurement information according to an embodiment of the present disclosure is shown.

[0070] According to an embodiment of the present disclosure, in network deployment or optimization, a mobile communication service provider may generally measure the signal strength in an expected service area, and deploy or rearrange base stations in the service area based on the measured signal strength. The service provider may load the signal measurement device on a vehicle and collect cell measurement information in the service area, which requires considerable time and cost. The process of loading the signal measurement device on a vehicle and collecting cell measurement information in the service area generally utilizes a vehicle and is therefore referred to as a drive test. The UE is equipped with functionality for measuring signals from the gNB to support operations such as cell reselection or switching and adding a service cell if migrating between cells.

[0071] Therefore, the UE in the service area can be used instead of the drive test, which is called minimization of drive test (MDT). The service provider can set the MDT operation for a specific UE through various devices of the network, and the UE can collect and store signal strength information from the serving cell and the neighboring cell in the connected mode RRC_Connected, the idle mode RRC_Idle, or the inactive mode RRC_Inactive. In addition, the UE can also store various information such as location information, time information, and signal quality information. If the UE is in the connected mode, the stored information can be reported to the network, and the reported information can be transmitted to a specific server.

[0072] According to an embodiment of the present disclosure, the MDT operation can be roughly divided into immediate MDT and logged MDT. Immediate MDT can be an operation in which the UE immediately reports the collected information to the network. Since the UE can report the collected information immediately, only terminals in connected mode can perform immediate MDT. Immediate MDT generally reuses the RRM measurement process to support operations such as handover and serving cell addition, and can additionally report location information, time information, etc.

[0073] Logged MDT may be an operation of not immediately reporting the collected information to the network and reporting the stored information after the UE switches to connected mode. A UE in idle mode that may not immediately report to the network may perform logged MDT. A UE in inactive mode introduced in a next generation mobile communication system may perform logged MDT. If a specific UE is in connected mode, the network may provide the UE with configuration information for performing a logged MDT operation, and the UE may collect and store the configuration information after switching to idle mode or inactive mode.

[0074] [Table 1]

[0075] RRC Status Instant MDT RRC_Connected Recorded MDT RRC_Idle, RRC_Inactive

[0076] Figure 1DA method for collecting and reporting cell measurement information according to an embodiment of the present disclosure is shown.

[0077] UE 1d-05 may switch from idle mode or inactive mode 1d-10 to connected mode 1d-15. UE 1d-05 may collect MDT data in connected mode and report to the gNB through immediate MDT operation. UE 1d-05 switched to connected mode may receive logged MDT configuration information 1d-20 performed in idle mode or inactive mode from the gNB. The logged MDT configuration information is included in a specific RRC message and transmitted to UE 1d-05, and UE 1d-05 receiving the RRC message may drive a first timer in operation 1d-55. UE 1d-05 may perform logged MDT operation during idle mode or inactive mode until the first timer expires. The value of the first timer may be included in the logged MDT configuration information. If UE 1d-05 switches to idle mode or inactive mode, the UE may perform logged MDT according to the configuration information received in operation 1d-25. UE 1d-05 may store specific information collected at intervals (i.e., at a recording interval 1d-35) in operations 1d-30 and 1d-45. In addition, if valid location information 1d-40 is collected, UE 1d-05 may need to store the valid location information. If a specific time 1d-50 has not passed after the location information is collected, whether the location information is valid may be determined to be valid. The specific time may be shorter than or equal to the recording interval.

[0078] Even before the first timer expires, the UE 1d-05 may temporarily stop the recorded MDT operation that has been performed if switched to connected mode in operation 1d-60. However, even during connected mode, the first timer continues to operate without stopping. That is, the first timer may continue to operate regardless of how the RRC state changes. It is noteworthy that the first timer may be stopped if the terminal memory for storing MDT data is insufficient and therefore no more storage space is available, or if the recorded MDT configuration information is released. Releasing the recorded MDT configuration information may correspond to, but is not limited to, providing other recorded MDT configuration information from a serving radio access technology (RAT) or another RAT, or detaching or shutting down the UE 1d-05.

[0079] During RRC connection establishment or RRC connection recovery, UE 1d-05 may report the collected information (MDT data) stored therein to the gNB using an RRC setup complete message or an RRC recovery complete message in operation 1d-65.

[0080] RRC connection establishment may include switching the UE 1d-05 from idle mode to connected mode. RRC connection establishment generally includes but is not limited to three steps and uses but is not limited to the following three types of RRC messages:

[0081] - Step 1: UE sends an RRC Setup Request message to gNB;

[0082] - Step 2: The gNB transmits an RRC setup message to the UE; and

[0083] -Step 3: The UE sends an RRC Setup Complete message to the gNB.

[0084] RRC connection recovery can switch the UE from inactive mode to connected mode. RRC connection recovery can generally include but not limited to three steps and use but not limited to the following three types of RRC messages:

[0085] - Step 1: UE sends an RRC recovery request message to gNB;

[0086] - Step 2: The gNB transmits an RRC recovery message to the UE; and

[0087] -Step 3: The UE sends an RRC recovery complete message to the gNB.

[0088] In addition to RRC connection establishment or RRC connection recovery, UE 1d-05 may report information indicating the collected information to the target gNB even during RRC connection reestablishment and handover procedures. If logged MDT has been configured but information is not collected and stored, the report may be omitted. The gNB receiving the report may request a report of the MDT data (i.e., the collected information) stored in UE 1d-05 when necessary. UE 1d-05 may need to continuously store unreported MDT data for a specific time. If UE 1d-05 returns to idle mode or inactive mode and the first timer has not expired, UE 1d-05 may restart logged MDT operation in operation 1d-70. If the first timer expires, UE 1d-05 may stop logged MDT operation in operation 1d-75. UE 1d-05 that stops logged MDT operation may drive a second timer in operation 1d-80 and maintain the stored MDT data until the second timer expires.

[0089] After the second timer expires, whether to delete the stored MDT data is determined by the implementation of the terminal. The value of the second timer may be included in the recorded MDT configuration information, or may not be configured to apply a predefined value. If UE 1d-05 switches back to connected mode, UE 1d-05 may report the collected information (MDT data) stored therein to the gNB in ​​operation 1d-85. The gNB may request a report of the MDT data stored in UE 1d-05 using a specific RRC message in operation 1d-90. Therefore, UE 1d-05 may include the MDT data stored in a specific RRC message and report the specific message to the gNB in ​​operation 1d-95.

[0090] Figure 1E A flow chart of operations for collecting and reporting cell measurement information according to an embodiment of the present disclosure is shown.

[0091] According to an embodiment of the present disclosure, UE 1e-05 may establish a connection with gNB 1e-10 in operation 1e-15. UE 1e-05 may provide UE capability information to gNB 1e-10 in operation 1e-20, and may provide information related to whether UE 1e-05 supports MDT operation and which frequency may be measured. gNB 1e-10 may include configuration information required to perform logged MDT operation in a specific RRC message, and transmit the RRC message to UE 1e-05 in operation 1e-25. For example, the configuration information required to perform logged MDT operation may include, but is not limited to, at least one of the following information:

[0092] - Track reference information;

[0093] - Track and record session reference information;

[0094] - Tracking Collection Entity (TCE) ID information: The gNB transmits the MDT data information reported from the UE to the data server specified by the TCE ID;

[0095] - Absolute time information: The absolute time information may include the absolute time of the current cell providing the recorded MDT configuration information;

[0096] -Regional configuration: The regional configuration information is regional information for collecting and storing measurement information through the logged MDT operation, and is indicated on a cell basis. In addition, the regional configuration information may include RAT information for collecting measurement information. The list included in the RAT information may be a blacklist or a whitelist. If the list is a blacklist, the UE collects cell measurement information of the RAT not included in the list. If the list is a whitelist, the UE does not collect cell measurement information of the RAT not included in the list;

[0097] - Logging duration: the logging duration information is the value of the first timer, and if the first timer is operating, the logged MDT operation is performed in the idle mode or the inactive mode;

[0098] -Recording interval: the interval for storing collected information;

[0099] - plmn-IdentityList (i.e., MDT Public Land Mobile Network (PLMN) List): It is PLMN list information, and the plmn-IdentityList information may contain PLMN information used not only for performing logged MDT operation but also for performing MDT data storage reporting and MDT data reporting. That is, if the registration (RPLMN) of the serving cell matches at least one PLMN in the PLMNs of the plmn-IdentityList, the UE receiving the plmn-IdentityList information may collect MDT measurement results in the corresponding cell or report the collected MDT measurement results;

[0100] -Indicator indicating whether the logged MDT operation is performed in idle mode, inactive mode, or both: The indicator may indicate whether the logged MDT operation is performed in idle mode, inactive mode, or both, the UE may indicate the RRC state for performing the logged MDT operation, or the UE may define that the logged MDT operation is always performed in idle mode and inactive mode without the indicator indicating whether the logged MDT operation is performed in idle mode, inactive mode, or both. The UE may perform the logged MDT operation only in the RRC state indicated by the indicator indicating whether the logged MDT operation is performed in idle mode, inactive mode, or both;

[0101] -Indicator indicating whether to collect and store beam-level measurement information: The next generation mobile communication system may adopt beam antennas. In the absence of an indicator indicating whether to collect and store beam-level measurement information, it may be defined that beam-level measurements are always collected and stored for frequencies performing beam-based operations;

[0102] - Information of the maximum number of beams collected or stored and information of the minimum signal strength of the stored beams: The UE may skip storing information of beams weaker than the minimum signal strength of the stored beams. If all beams are weaker than the configured minimum signal value, the UE may store information of one beam with the maximum signal strength, or may include an indicator indicating that all beams are weaker than the configured minimum signal value.

[0103] The UE 1e-05 receiving the logged MDT configuration information may drive a first timer in operation 1e-30. The value of the first timer may be configured to be equal to the value of the logging duration. The gNB 1e-10 may switch the UE 1e-05 to an idle mode or an inactive mode using an RRC release message in operation 1e-35. Depending on the converted RRC state, the RRC release message may contain configuration information for the operation in the RRC state. If the first timer is being driven, the UE 1e-05 may perform logged MDT in an idle mode or an inactive mode in operation 1e-40. The UE 1e-05 measures the signal strength of the serving cell and the neighboring cells and acquires location information. If beam-level measurement is configured, the UE 1e-05 may collect and store signal strength values ​​of beams greater than a configured minimum value in the serving cell and the neighboring cells. The maximum number of beams to be stored may be configured or predefined. The signal strength may indicate a reference signal received power (RSRP), a reference signal received quality (RSRQ), or a signal-to-noise and interference ratio (SINR). The UE 1e-05 may store the collected information at a logging interval. If the first timer expires in operation 1e-45, the UE 1e-05 may stop the logged MDT operation in operation 1e-50.

[0104] If UE 1e-05 is in idle mode or inactive mode according to the RRC release message, and receives RAN or CN paging or activates MO (mobile originated) data transmission from gNB 1e-10, UE 1e-05 can initialize a setup procedure or a recovery procedure to transition from idle mode or inactive mode to connected mode.

[0105] The establishment process or recovery process may include:

[0106] -Step 1: The UE transmits an RRC setup request message or an RRC recovery request message to the gNB (operation 1e-55);

[0107] -Step 2: The gNB transmits an RRC setup message or an RRC resume message to the UE (operation 1e-60); and

[0108] -Step 3: The UE transmits an RRC setup complete message or an RRC recovery complete message to the gNB (operation 1e-65).

[0109] The UE 1e-05 may include an indicator indicating whether MDT data is stored therein in an RRC setup complete or RRC recovery complete message. In operation 1e-70, the gNB 1e-10 receiving the RRC setup complete message may request an MDT data report using a specific RRC message (ie, UEInformationRequest) when necessary. In operation 1e-75, the UE 1e-05 receiving the MDT data report request may report the MDT data using a specific RRC message (ie, UEInformationResponse).

[0110] Figure 1F An accessed (V) independent non-public network S(NPN) according to an embodiment of the present disclosure is shown.

[0111] The NR mobile communication system of Release 16 has been improved to support non-public networks (NPNs). NPNs are roughly divided into closed access groups (CAGs) and SNPNs. CAG is also called public network integrated NPN (PNI-NPN) and indicates an NPN deployed by utilizing a public network provided by a mobile communication service provider. To indicate a PNI-NPN, the gNB may broadcast a system information block (SIB) 1 including a PNI-NPN ID.

[0112] The PNI-NPN ID may include a PLMN ID and a CAG ID, and the PLMN ID may indicate one ID in a PLMN of a mobile communication service provider providing a cell.

[0113] In contrast, the SNPN may indicate an NPN that is not associated with a network provided by a mobile communication service provider. To indicate the SNPN, the gNB may broadcast SIB1 including the SNPN ID. The SNPN ID may include a PLMN ID and a network identity (NID), and the PLMN ID and the NID may be independent of the mobile communication service provider. The UE may be set to SNPN mode in which normal cell reselection operations are not performed. If the SNPN mode is not set, the UE may perform normal cell reselection operations when camping on a SNPN cell.

[0114] According to an embodiment of the present disclosure, the UE obtains NPN information to be accessed in advance, and determines whether to access a cell by considering the PNI-NPN or SNPN ID broadcasted in SIB1.

[0115] In the present disclosure, SNPN can support external service providers. In the present disclosure, this is referred to as a home service provider (SP) 1f-15 or a credential holder (CH). For example, in order to wirelessly control a smart factory, a SNPN network can be built. Workers working in a smart factory may want to receive services from an external service provider through the SNPN network. The external service provider may be an existing wired / wireless communication service provider. In this case, the AMF and session management function (SMF) in the SNPN of the smart factory can be connected to the network entity of the external service provider to interconnect the user and the external service provider. The SNPN is called V-SNPN 1f-10. V-SNPN 1f-10 can broadcast the (group) ID information of its home SP using system information. The ID information of the home SP is called the group ID (GIN) for network selection. The GIN may include a PLMN ID and a NID, and is provided to the UE via SIB18 as a new system information. The SIB18 extracted from the technical specification (TS) 38.331 is as follows.

[0116] [Table 2]

[0117]

[0118]

[0119] [Table 3]

[0120]

[0121] [Table 4]

[0122]

[0123] The UE 1f-05 receiving the system information can use the pre-acquired specific configuration information to determine whether to access the V-SNPN. In the present disclosure, in terms of access using credentials, the access of the UE 1f-05 to the V-SNPN is referred to as credential access or external CH access. For example, the list information of V-SNPNs allowed to be accessed may be included in the specific configuration information (subscription credentials and configuration).

[0124] Figure 1G Data loading (O)-SNPN according to an embodiment of the present disclosure is shown.

[0125] As mentioned above, the UE that triggers the credential access already has the credential access related configuration information, and the V-SNPN (gNB of V-SNPN) can use system information to broadcast the ID information of the home SP it supports. The UE can determine whether to access the cell by considering the V-SNPN ID broadcast by the V-SNPN gNB in ​​SIB1.

[0126] However, in some cases, the UE 1g-05 may not have the credential access related configuration information. The SNPN that supports the UE 1g-05 to access the gNB to obtain the credential access related configuration information from the specific server 1g-15 is called O-SNPN 1g-10. In the present disclosure, attempting to access the O-SNPN to obtain the credential access related configuration information is called data loading access.

[0127] In order to support SNPN, a new system information SIB18 is used. SIB18 may include the above-mentioned GIN information. In addition, SIB18 may also include an indicator indicating whether the cell broadcasting SIB18 supports V-SNPN or O-SNPN. For example:

[0128] -extCH-Support-r17 field: indicates whether the corresponding cell supports voucher access (i.e. external CH access);

[0129] -extCH-WithoutConfigAllowed-r17 field: indicates whether the corresponding cell supports credentialed access by UEs without SNPN related configuration;

[0130] - onboardingEnabled-r17 field: indicates whether the corresponding cell supports data onboarding access; and / or

[0131] -imsEmergencySupportForSNPN-r17 field: indicates whether the corresponding cell supports Internet Protocol (IP) Multimedia Subsystem (IMS) emergency calls for SNPN.

[0132] The present disclosure proposes to collect and report the measurement information required for NPN optimization at the UE through logged MDT, cell establishment failure (CEF) reporting and radio link failure (RLF) reporting. In conjunction with the new collected information, the present disclosure introduces a process for performing NPN check operations for collection or reporting.

[0133] Figure 1H A flowchart illustrating an operation of collecting and reporting NPN-related information through logged MDT according to an embodiment of the present disclosure.

[0134] UE 1h-05 may report its capability information to gNB 1h-10 in operation 1h-13. The capability information may include indicator information indicating that UE 1h-05 may collect and report measurement information required for NPN optimization through logged MDT, CEF reporting, and RLF reporting.

[0135] UE 1h-05 may receive a LoggedMeasurementConfiguration message including logged MDT configuration information from gNB 1h-10 in operation 1h-15. UE 1h-05 may be connected to gNB 14-10 as an NPN. According to an embodiment of the present disclosure, the LoggedMeasurementConfiguration message may include npn-IdentityList and GIN related information.

[0136] The npn-IdentityList information is NPN ID (PNI-NPN ID or SNPN ID) list information, and may contain NPN ID information used not only for performing logged MDT but also for performing MDT data storage reporting and MDT data reporting.

[0137] The GIN related information is GIN list information, and may include GIN information used not only for performing logged MDT but also for performing MDT data storage reporting and MDT data reporting. The GIN list may be, but is not limited to, a list of PLMN and NID combinations, or a list of GIN index values ​​indicated in SIB18. If the GIN related information is provided as a list of GIN index values ​​indicated in SIB18, the UE 1h-05 may directly search for and store the GIN ID (a combination of PLMN and NID) corresponding to the GIN index from the received SIB18.

[0138] Using the information contained in the LoggedMeasurementConfiguration, the UE 1h-05 can determine whether to perform logged MDT, MDT data storage reporting, and MDT data reporting in a specific cell. In doing so, the UE 1h-05 can make different determinations depending on whether the cell transmitting the LoggedMeasurementConfiguration message is a PNI-NPN or a SNPN.

[0139] According to an embodiment of the present disclosure, since PNI-NPN provides a logical private network via NPN, the entity that actually optimizes the physical mobile communication network may be an existing mobile communication service provider. Therefore, UE 1h-05 may determine whether to report MDT data collected through logged MDT in a specific cell through the plmn-IdentityList information configured by the conventional LoggedMeasurementConfiguration message. That is, if the RPLMN matches at least one PLMN of the plmn-IdentityList in the serving cell, the UE 1h-05 that receives the information contained in the LoggedMeasurementConfiguration may collect MDT measurement results in the corresponding cell or report the collected MDT measurement results.

[0140] On the other hand, the mobile communication service provider may want to optimize the network based on the PNI-NPN. Therefore, the UE 1h-05 can determine whether to report the MDT data collected through the logged MDT by considering both the plmn-IdentityList information and the npn-IdentityList information or only by considering the npn-IdentityList information. By considering both the plmn-IdentityList information and the npn-IdentityList information, if the PLMN supported in the serving cell matches at least one PLMN of the plmn-IdentityList, and the PNI-NPN selected or registered by the UE matches at least one PNI-NPN of the npn-IdentityList, the UE 1h-05 can collect MDT measurement results in the corresponding cell or report the collected MDT measurement results.

[0141] In contrast, by considering only the npn-IdentityList information, if the PNI-NPN selected or registered by the UE matches at least one PNI-NPN of the npn-IdentityList, the UE 1h-05 may collect MDT measurement results in the corresponding cell or report the collected MDT measurement results.

[0142] Since SNPN is a dedicated network separated from the existing mobile communication network, UE 1h-05 can determine whether to report MDT data collected through recorded MDT by considering only the npn-IdentityList information. That is, if the SNPN selected or registered by UE 1h-05 matches at least one SNPN in the npn-IdentityList, UE 1h-05 can collect MDT measurement results in the corresponding cell or report the collected MDT measurement results. SNPN has been developed to support credential access or data loading access. Therefore, SNPN can collect MDT measurement results based on a specific GIN, and for this purpose, the gedMeasurementConfiguration message can include GIN-related information for collecting MDT measurement results or reporting collected MDT measurement results.

[0143] Therefore, the UE 1h-05 can determine whether to report the MDT data collected through the logged MDT in a specific cell by considering both the npn-IdentityList information and the GIN-related information or by considering only the GIN-related information. By considering both the npn-IdentityList information and the GIN-related information, if the SNPN selected or registered by the UE 1h-05 matches at least one SNPN in the npn-IdentityList, and at least one of the GINs supported in the corresponding cell matches at least one GIN included in the GIN-related information, the UE 1h-05 can collect MDT measurement results in the corresponding cell or report the collected MDT measurement results.

[0144] In contrast, by considering only the GIN-related information, if at least one of the GINs supported in the corresponding cell matches at least one GIN included in the GIN-related information, the UE 1h-05 may collect MDT measurement results in the corresponding cell or report the collected MDT measurement results.

[0145] The UE 1h-05 receiving the LoggedMeasurementConfiguration message may drive a specific timer, namely T330, in operation 1h-20. In operation 1h-30, the UE 1h-05 may receive an RRCRelease message from the gNB and switch to RRC_IDLE or RRC_INACTIVE depending on whether the RRCRelease message includes the suspendConfig IE. In operation 1h-35, the UE 1h-05 switched to RRC_IDLE or RRC_INACTIVE may collect and store MDT measurement results according to the MDT configuration information included in the LoggedMeasurementConfiguration message.

[0146] In operation 1h-40, through cell (re)selection, the UE 1h-05 camping on a cell can receive NPN-related configuration information in SIB1 and SIB18 broadcast by the cell. In operation 1h-45, in this case, based on the new MDT configuration information contained in the LoggedMeasurementConfiguration message, the information contained in SIB1 and SIB18, the UE 1h-05 can determine whether to perform logged MDT in the corresponding cell. In operation 1h-50, if the NPN-related measurement results are stored, the UE 1h-05 can store the following new information:

[0147] -Whether the corresponding cell supports external CH access or data loading access;

[0148] -GIN information supported in the corresponding cell, i.e. SIB18 (partial) content;

[0149] - The ID of the NPN on which the UE is camped, or the ID of the NPN selected or registered by the UE (PLMN+CAG ID or PLMN+NID);

[0150] - GIN information (list of PLMN+NID combinations) supportable by the UE in the GIN supported by the corresponding cell; and / or

[0151] -NPN related indicator information provided by the corresponding cell through SIB1, namely extCH-Support-r17, extCH-WithoutConfigAllowed-r17, onboardingEnabled-r17, and imsEmergencySupportForSNPN-r17.

[0152] Through conventional logged MDT, the collected information may be stored together. The above new information may not be stored in each record, and may be stored in at least one of the records collected in one serving cell.

[0153] In operation 1h-55, UE 1h-05 may report to the gNB an availability indicator indicating new information stored during RRC establishment, RRC recovery, RRC reestablishment, or RRCReconfiguration. Before reporting the availability indicator, UE 1h-05 may perform a PLMN / NPN check in operation 1h-60.

[0154] In the PLMN / NPN check of the PNI-NPN, by considering both the plmn-IdentityList information and the npn-IdentityList information, if the RPLMN matches at least one PLMN of the plmn-IdentityList and the PNI-NPN selected or registered by the UE1h-05 matches at least one PNI-NPN of the npn-IdentityList, the UE 1h-05 can report an availability indicator to the corresponding cell. On the contrary, by considering only the npn-IdentityList information, if the PNI-NPN selected or registered by the UE 1h-05 matches at least one PNI-NPN of the npn-IdentityList, the UE 1h-05 can report an availability indicator to the corresponding cell.

[0155] In the PLMN / NPN check of the SNPN, by considering both the npn-IdentityList information and the GIN-related information, if the SNPN selected or registered by the UE 1h-05 matches at least one SNPN in the npn-IdentityList, and at least one of the GINs supported in the corresponding cell matches at least one GIN included in the GIN-related information, the UE 1h-05 can report an availability indicator to the corresponding cell. On the contrary, by considering only the GIN-related information, if at least one of the GINs supported in the corresponding cell matches at least one GIN included in the GIN-related information, the UE 1h-05 can report an availability indicator to the corresponding cell.

[0156] The availability indicator may be included in an RRCSetupComplete message, an RRCResumeComplete message, an RRCReestablishmentComplete message, or an RRCReconfigurationComplete message and reported to the gNB 1h-10 in operation 1h-65.

[0157] The gNB 1h-10 receiving the availability indicator may request the MDT measurement results stored in the UE 1h-05 using the UEInformationRequest message in operation 1h-70. The UE 1h-05 receiving the MDT measurement result request may report its stored MDT measurement results to the gNB 1h-10 using the UEInformationResponse message in operation 1h-75.

[0158] Fig. 1I A flow chart illustrating a UE operation for collecting and reporting NPN-related information through logged MDT according to an embodiment of the present disclosure.

[0159] In operation 1i-05, the UE may receive a LoggedMeasurementConfiguration message from the gNB. The LoggedMeasurementConfiguration message may include configuration information required to collect and report NPN related information.

[0160] In operation 1i-10, the UE may receive the RRCRelease message and switch to an idle mode or an inactive mode.

[0161] In operation 1i-15, the UE may perform a logged MDT operation according to the configuration information received in the LoggedMeasureemntConfiguration message.

[0162] In operation 1i-20, if a specific condition is met, the UE may collect and store NPN related information. According to an embodiment of the present disclosure, if a specific condition is met by performing a logged MDT operation, the UE may collect NPN related information and store the collected NPN related information as an MDT measurement result.

[0163] In operation 1i-25, the UE may switch to the connected mode through the RRC (re) establishment or RRC recovery process. During the RRC (re) establishment or RRC recovery process, the UE may report an indicator indicating the presence of the stored MDT measurement results to the gNB.

[0164] In operation 1i-30, the UE may receive an MDT measurement result report request from the gNB.

[0165] In operation 1i-35, the UE may report its stored MDT measurement results to the gNB.

[0166] Figure 1J A flowchart of gNB operations for collecting and reporting NPN-related information via logged MDT according to an embodiment of the present disclosure is shown.

[0167] In operation 1j-05, the gNB may transmit a LoggedMeasurementConfiguration message to the UE. The LoggedMeasurementConfiguration message may include npn-IdentityList and GIN related information.

[0168] In operation 1j-10, the gNB may transmit a RRCRelease message to the UE.

[0169] In operation 1j-15, the gNB may receive a specific RRC message including an availability indicator from the UE.

[0170] In operation 1j-20, the gNB may use a UEInformationRequest message to request the UE to report the stored MDT measurement results.

[0171] In operation 1j-25, the gNB may receive a UEInformationResponse message including the MDT measurement result from the UE.

[0172] Figure 1K A flow chart illustrating operations for collecting and reporting NPN related information through CEF reporting according to an embodiment of the present disclosure is shown.

[0173] UE 1k-05 that wishes to access the NPN may receive SIB1 and SIB18 broadcasts from gNB 1k-10 in operation 1k-15. Through SIB1 and SIB18, UE 1k-05 may attempt NPN access to gNB 1k-10. In doing so, UE 1k-05 transmits an RRCSetupRequest or RRCResumeRequest message to gNB 1k-10 in operation 1k-20. If an RRCSetupRequest or RRCResumeRequest message is transmitted, UE 1k-05 may drive the T300 (for RRCSeupRequest transmission) or T319 (for RRCResumeRequest transmission) timer in operation 1k-25. If gNB 1k-10 is not successfully accessed until the T300 or T319 timer expires, UE 1k-05 may regard the NPN access attempt as an RRC establishment failure or an RRC recovery failure.

[0174] In this case, UE 1k-05 may store the CEF report content in operation 1k-35. The present disclosure suggests new NPN related information as follows, as the CEF report content in operation 1k-40:

[0175] - The ID of the NPN that the UE is trying to access (PNI-NPN ID (PLMN+CAG ID) or SNPN ID (PLMN+NID)). The ID of the NPN is selected by the UE Non-Access Stratum (NAS). In the CEF report, the information can be used for NPN checking;

[0176] - GIN information (PLMN+NID) that the UE attempts to access. The GIN information is selected by the UE NAS. In the CEF report, the GIN information (PLMN+NID) that the UE 1k-05 attempts to access can be used for NPN check;

[0177] -Whether the corresponding access is used to connect to the NPN cell;

[0178] -Whether the corresponding access is used to connect to a PNI-NPN cell or a SNPN cell;

[0179] -The corresponding access is external CH access or data loading access;

[0180] - GIN information (PLMN+NID combination list) that can be supported by UE 1k-05 in the GIN supported by the corresponding cell;

[0181] - GIN information supported in the corresponding cell, i.e. SIB18 (partial) content; and / or

[0182] -NPN related indicator information provided by the corresponding cell through SIB1, namely extCH-Support-r17, extCH-WithoutConfigAllowed-r17, onboardingEnabled-r17, and imsEmergencySupportForSNPN-r17.

[0183] According to an embodiment of the present disclosure, the UE 1k-05 may store the information together with the regular CEF report content. For example, in PNI-NPN access, the UE 1k-05 may store the PLMN value selected by the UE NAS.

[0184] In operation 1h-45, UE 1k-05 may report to the gNB an availability indicator indicating a CEF report stored during RRC establishment, RRC recovery, RRC reestablishment, or RRCReconfiguration. Before reporting the availability indicator, UE 1k-05 may perform a PLMN / NPN check in operation 1k-50.

[0185] In the PLMN / NPN check of the PNI-NPN, both the PLMN and the PNI-NPN stored in the CEF report content are considered, and if the RPLMN matches the stored PLMN and the PNI-NPN selected or registered by the UE 1k-05 matches the stored PNI-NPN, the UE 1k-05 can report an availability indicator to the corresponding cell. Conversely, by considering only the stored PNI-NPN, if the PNI-NPN selected or registered by the UE 1k-05 matches the stored PNI-NPN, the UE 1k-05 can report an availability indicator to the corresponding cell.

[0186] In the PLMN / NPN check of SNPN, by considering both the SNPN and GIN information stored in the CEF report content (i.e., the GIN that UE1k-05 attempts to access), if the SNPN selected or registered by UE 1k-05 matches the stored SNPN, and at least one of the GINs supported in the corresponding cell (or the GIN selected by UE 1k-05) matches the stored GIN, UE 1k-05 can report an availability indicator to the corresponding cell. On the contrary, by considering only GIN-related information, if at least one of the GINs supported in the corresponding cell (or the GIN selected by UE 1k-05) matches the stored GIN, UE 1k-05 can report an availability indicator to the corresponding cell.

[0187] The availability indicator may be included in an RRCSetupComplete message, an RRCResumeComplete message, an RRCReestablishmentComplete message, or an RRCReconfigurationComplete message and reported to gNB 1k-10 in operation 1h-55.

[0188] The gNB 1k-10 receiving the availability indicator may request the CEF report stored in the UE 1k-05 using the UEInformationRequest message in operation 1k-60. The UE 15-05 receiving the CEF report request may report its stored CEF report to the gNB 1k-10 using the UEInformationResponse message in operation 1k-65.

[0189] Figure 1L A flow chart of UE operations for collecting and reporting NPN-related information through CEF reporting according to an embodiment of the present disclosure is shown.

[0190] In operation 1L-05, the UE may transmit an RRCSetupRequest or RRCResumeRequest message to the gNB for NPN access. In doing so, the T300 or T319 timer may operate.

[0191] In operation 1L-10, the UE may recognize that the T300 or T319 timer expires.

[0192] In operation 1L-15, the UE may configure CEF report content.

[0193] In operation 1L-20, the UE may store the NPN related information as CEF report content.

[0194] In operation 1L-25, the UE may switch to connected mode through an RRC (re)establishment or RRC recovery procedure. The UE may report an indicator indicating a stored CEF report to the gNB.

[0195] In operation 1L-30, the UE may receive a CEF report request from the gNB.

[0196] In operation 1L-35, the UE may report its stored CEF report to the gNB.

[0197] Figure 1M A flow chart of operations for collecting and reporting NPN-related information through RLF reporting according to an embodiment of the present disclosure is shown.

[0198] refer to Figure 1M , UE 1m-05 may connect to gNB 1m-10 through NPN in operation 1m-15. UE 1m-05 may identify radio link failure or handover failure (HOF) in operation 1m-20. In this case, UE 1m-05 may store RLF report content in operation 1m-25. The present disclosure may suggest new NPN related information as RLF report content in operation 1m-30 as follows:

[0199] - ID of the NPN to which the UE 1m-05 is connected (PNI-NPN ID (PLMN+CAG ID) or SNPN ID (PLMN+NID)). The ID of the NPN is selected by the UE NAS. The ID of the NPN to which the UE 1m-05 is connected can be used for NPN check in the CEF report;

[0200] -GIN information (PLMN+NID) to which UE 1m-05 is connected. The GIN information is selected by UE NAS. In the CEF report, the GIN information to which UE 1m-05 is connected can be used for NPN check;

[0201] -Whether the corresponding access is a connection to an NPN cell;

[0202] -Whether the corresponding access is a connection to a PNI-NPN cell or a SNPN cell;

[0203] -The corresponding access is external CH access or data loading access;

[0204] - GIN information (PLMN+NID combination list) that can be supported by UE 1m-05 in the GIN supported by the corresponding cell;

[0205] - GIN information supported in the corresponding cell, i.e. SIB18 (partial) content; and / or

[0206] -NPN related indicator information provided by the corresponding cell through SIB1, namely extCH-Support-r17, extCH-WithoutConfigAllowed-r17, onboardingEnabled-r17, and imsEmergencySupportForSNPN-r17.

[0207] According to an embodiment of the present invention, the UE may store the collected information together with the existing RLF report content. For example, the PNI-NPN access may store the PLMN value selected by the UE NAS.

[0208] In operation 1m-35, the UE 1m-05 may report to the gNB an availability indicator indicating an RLF report stored in RRC establishment, RRC recovery, RRC re-establishment, or RRCReconfiguration. Before reporting the availability indicator, the UE 1m-05 may perform a PLMN / NPN check in operation 1m-40.

[0209] In the PLMN / NPN check of the PNI-NPN, both the PLMN and the PNI-NPN stored in the RLF report content are considered, and if the RPLMN matches the stored PLMN and the PNI-NPN selected or registered by the UE 1m-05 matches the stored PNI-NPN, the UE 1m-05 can report an availability indicator to the corresponding cell. Conversely, by considering only the stored PNI-NPN, if the PNI-NPN selected or registered by the UE 1m-05 matches the stored PNI-NPN, the UE 1m-05 can report an availability indicator to the corresponding cell.

[0210] In the PLMN / NPN check of SNPN, by considering both the SNPN and GIN information stored in the RLF report content (i.e., the GIN that UE1m-05 attempts to access), if the SNPN selected or registered by UE 1m-05 matches the stored SNPN, and at least one of the GINs supported in the corresponding cell (or the GIN selected by UE 1m-05) matches the stored GIN, UE 1m-05 can report an availability indicator to the corresponding cell. On the contrary, by considering only GIN-related information, if at least one of the GINs supported in the corresponding cell (or the GIN selected by UE 1m-05) matches the stored GIN, UE 1m-05 can report an availability indicator to the corresponding cell.

[0211] The availability indicator may be included in an RRCSetupComplete message, an RRCResumeComplete message, an RRCReestablishmentComplete message, or an RRCReconfigurationComplete message and reported to gNB 1m-10 in operation 1m-45.

[0212] The gNB 1m-10 receiving the availability indicator may request the RLF report stored in the UE 1m-05 using the UEInformationRequest message in operation 1m-50. The UE 1m-05 receiving the RLF report request may report its stored RLF report to the gNB 1m-10 using the UEInformationResponse message in operation 1m-55.

[0213] Figure 1N A flow chart of UE operation for collecting and reporting NPN-related information through RLF reporting according to an embodiment of the present disclosure is shown.

[0214] In operation 1n-05, the UE can connect to the gNB through NPN.

[0215] In operation 1n-10, the UE may identify the RLF or the HOF.

[0216] In operation 1n-15, the UE may configure RLF report content.

[0217] In operation 1n-20, the UE may store the NPN related information as RLF report content.

[0218] In operation 1n-25, the UE may switch to the connected mode through the RRC (re) establishment or RRC recovery process. During the RRC (re) establishment or RRC recovery process, the UE may report an indicator indicating the stored RLF report to the gNB.

[0219] In operation 1n-30, the UE may receive a RLF report request from the gNB.

[0220] In operation 1n-35, the UE may report its stored RLF report to the gNB.

[0221] Fig.1O A block diagram showing an internal structure of a terminal according to an embodiment of the present disclosure.

[0222] refer to Fig.1O , the UE may include a radio frequency (RF) processor 1o-10, a baseband processor 1o-20, a storage device 1o-30, and a controller 1o-40. The UE is not limited to this example, and may include more Fig.1O Fewer or more components than shown.

[0223] The RF processor 1o-10 can perform functions for transmitting or receiving signals through a radio wireless channel, such as signal band conversion and amplification. That is, the RF processor 1o-10 can up-convert the baseband signal provided from the baseband processor 1o-20 into an RF band signal, transmit the RF band signal via an antenna, and down-convert the RF band signal received through the antenna into a baseband signal. For example, the RF processor 1o-10 may include, but is not limited to, a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), and the like. Although Fig.1O Only one antenna is shown in the figure, but the terminal may include multiple antennas. The RF processor 1o-10 may include multiple RF chains. In addition, the RF processor 1o-10 may perform beamforming. For beamforming, the RF processor 1o-10 may adjust the phase and amplitude of signals transmitted and received via multiple antennas or antenna elements. The RF processor 1o-10 may perform MIMO and receive several layers when performing MIMO operations.

[0224] The baseband processor 1o-20 can perform the conversion function between the baseband signal and the bit stream according to the physical layer standard of the system. For example, in data transmission, the baseband processor 1o-20 can generate complex symbols by encoding and modulating the transmitted bit stream. In data reception, the baseband processor 1o-20 can recover the received bit stream by demodulating and decoding the baseband signal provided from the RF processor 1o-10. For example, according to OFDM, in data transmission, the baseband processor 1o-20 can generate complex symbols by encoding and modulating the transmitted bit stream, map the complex symbols to subcarriers, and construct OFDM symbols through inverse fast Fourier transform (IFFT) and cyclic prefix (CP) insertion. In addition, in data reception, the baseband processor 1o-20 can divide the baseband signal provided from the RF processor 1o-10 into OFDM symbols, recover the signals mapped to the subcarriers through FFT, and recover the received bit stream by demodulating and decoding these signals.

[0225] The baseband processor 1o-20 and the RF processor 1o-10 can transmit and receive signals, as described above. Therefore, the baseband processor 1o-20 and the RF processor 1o-10 can be referred to as a transmitter, a receiver, a transceiver or a communicator. In addition, at least one of the baseband processor 1o-20 or the RF processor 1o-10 may include multiple communication modules for supporting a variety of different RATs. In addition, at least one of the baseband processor 1o-20 or the RF processor 1o-10 may include multiple communication modules for processing signals in different frequency bands. For example, different RATs may include a wireless local area network (LAN) (e.g., IEEE 802.11), a cellular network (e.g., LTE), etc. In addition, different frequency bands may include ultra-high frequency (SHF, e.g., 2.5 GHz or 5 GHz) bands and millimeter wave (mmWave) (e.g., 60 GHz) bands. The terminal may transmit signals to and receive signals from a base station using the baseband processor 1o-20 and the RF processor 1o-10, and the signals may include control information and data.

[0226] The storage device 1o-30 may store data, such as basic programs, applications, and configuration information for the operation of the terminal. Specifically, the storage device 1o-30 may store information related to a second access node that uses a second RAT to perform wireless communication. The storage device 1o-30 provides the stored data at the request of the controller 1o-40. The storage device 1o-30 may include a storage medium, such as a read-only memory (ROM), a random access memory (RAM), a hard disk, a compact disk (CD)-ROM, and a digital versatile disk (DVD) or a combination of storage media. In addition, the storage device 1o-30 may include multiple memories. According to some embodiments, the storage device 1o-30 may store a program for executing a method for optimizing NPN according to the present disclosure.

[0227] The controller 1o-40 can control the overall operation of the terminal. For example, the controller 1o-40 can transmit and receive signals through the baseband processor 1o-20 and the RF processor 1o-10. The controller 1o-40 records data in the storage device 1o-30 and reads data from it. To this end, the controller 1o-40 may include at least one processor. For example, the controller 1o-40 may include a communication processor (CP) for performing communication control and an application processor (AP) for controlling a high level (such as an application). In addition, at least one configuration of the terminal can be implemented with a single chip.

[0228] Figure 1P The configuration of a base station according to the present disclosure is shown.

[0229] like Figure 1P As shown, the base station includes an RF processor 1p-10, a baseband processor 1p-20, a backhaul communicator 1p-30, a storage device 1p-40, and a controller 1p-50. The base station is not limited to this example, and may include Figure 1P In addition, the network entity (or network function) may be the same as or correspond to the base station.

[0230] The RF processor 1p-10 can perform functions such as frequency band conversion and amplification to transmit and receive signals through a radio channel. That is, the RF processor 1p-10 can up-convert the baseband signal provided from the baseband processor 1p-20 into an RF band signal, transmit the RF band signal via an antenna, and down-convert the RF band signal received through the antenna into a baseband signal. For example, the RF processor 1p-10 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, and the like. Although Figure 1POnly one antenna is shown in the figure, but the base station may also include multiple antennas. The RF processor 1p-10 may include multiple RF chains. In addition, the RF processor 1p-10 may perform beamforming. For beamforming, the RF processor 1p-10 may adjust the phase and amplitude of signals transmitted and received through multiple antennas or antenna elements. The RF processor 1p-10 may perform DL MIMO operations by transmitting one or more layers.

[0231] The baseband processor 1p-20 can perform a conversion function between a baseband signal and a bit string according to the physical layer standard of the first RAT. For example, in data transmission, the baseband processor 1p-20 can generate complex symbols by encoding and modulating the transmitted bit stream. In data reception, the baseband processor 1p-20 can recover the received bit stream by demodulating and decoding the baseband signal provided from the RF processor 1p-10. For example, according to OFDM, in data transmission, the baseband processor 1p-20 can generate complex symbols by encoding and modulating the transmitted bit stream, mapping the complex symbols to subcarriers, and constructing OFDM symbols through IFFT and CP insertion. In addition, in data reception, the baseband processor 1p-20 can divide the baseband signal provided from the RF processor 1p-10 into OFDM symbols, recover the signals mapped to the subcarriers through FFT, and recover the received bit stream by demodulating and decoding these signals. The baseband processor 1p-20 and the RF processor 1p-10 can transmit and receive signals as described above.

[0232] Therefore, the baseband processor 1p-20 and the RF processor 1p-10 can be referred to as a transmitter, a receiver, a transceiver, a communicator, or a wireless communicator. The base station can use the baseband processor 1p-20 and the RF processor 1p-10 to transmit and receive signals to and from the terminal, and the signals may include control information and data.

[0233] The backhaul communicator 1p-30 may provide an interface for communicating with other nodes in the network. That is, the backhaul communicator 1p-30 may convert a bit stream transmitted to another node (e.g., an auxiliary base station, a core network, etc.) into a physical signal, and convert a physical signal received from another node into a bit stream. The backhaul communicator 1p-30 may be included in the communication unit.

[0234] The storage device 1p-40 may store data such as basic programs, applications, and configuration information for the operation of the base station. Specifically, the storage device 1p-40 may store information on the bearers assigned to the connected terminals and measurement results reported from the connected terminals. The storage device 1p-40 may store information for determining whether to provide or stop multiple connections to the terminal. The storage device 1p-40 may provide the stored data at the request of the controller 1p-50. The storage device 1p-40 may include a storage medium such as a ROM, RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media. In addition, the storage device 1p-40 may include a plurality of memories. According to some embodiments, the storage device 1p-40 may store a program for executing a method for optimizing NPN according to the present disclosure.

[0235] The controller 1p-50 may control the general operation of the base station. For example, the controller 1p-50 may transmit and receive signals through the baseband processor 1p-20 and the RF processor 1p-10 or the backhaul communicator 1p-30. The controller 1p-50 records data in the storage device 1p-40 and reads data from it. To this end, the controller 1p-50 may include at least one processor. In addition, at least one configuration of the base station may be implemented with a single chip.

[0236] The present disclosure provides a method for reporting an MDT measurement result of a terminal, the method comprising: receiving configuration information required for collecting and reporting NPN related information from a base station; performing logged MDT based on the configuration information in an idle mode or an inactive mode; storing the MDT measurement result based on the logged MDT; if switching to an RRC connected state, transmitting an indicator indicating the stored MDT measurement result to the base station; receiving a report request for the MDT measurement result from the base station and reporting the MDT measurement result to the base station.

[0237] The methods according to the embodiments described in the claims or the specification of the present disclosure may be implemented in hardware, software, or a combination of hardware and software.

[0238] In terms of software, a computer-readable storage medium storing one or more programs (software modules) may be provided. One or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors of an electronic device. One or more programs may include instructions for controlling an electronic device to perform a method according to an embodiment described in the claims or this disclosure.

[0239] Such a program (software module, software) may be stored in a random access memory, a non-volatile memory including a flash memory, a read-only memory (ROM), an electrically erasable programmable ROM (EEPROM), a magnetic disk storage device, a CD-ROM, a DVD or other optical storage device, and a magnetic tape cassette. Alternatively, the program may be stored in a memory combining some or all of these recording media. A plurality of memories may be included.

[0240] In addition, the program can be stored in an attachable storage device, which can be accessed via a communication network, such as the Internet, an intranet, a LAN, a wide area network (WLAN) or a storage area network (SAN), or a communication network that combines these networks. Such a storage device can access the device that performs the embodiments of the present disclosure through an external port. In addition, an independent storage device on a communication network can access the device that performs the embodiments of the present disclosure.

[0241] In the specific embodiments of the present disclosure, the components included in the present disclosure are expressed in singular or plural form. However, for ease of explanation, singular or plural expression is appropriately selected according to the provided situation, the present disclosure is not limited to a single component or multiple components, a component expressed in plural form can be configured as a single component, and a component expressed in singular form can be configured as multiple components.

[0242] Although specific embodiments of the present disclosure have been described in detail, it will be understood by those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the present disclosure. Therefore, the scope of the present disclosure is not limited by the embodiments of the present disclosure, but by the claims, and all modifications or substitutions derived from the scope and spirit of the claims and their equivalents fall within the scope of the present disclosure. That is, it will be apparent to those of ordinary skill in the art that various modifications may be made based on the technical scope of the present disclosure. In addition, the embodiments of the present disclosure may be combined as needed. For example, some methods provided by the present disclosure may be combined with each other to operate gNB and UE. In addition, although the embodiments of the present disclosure are recommended based on 5G and NR systems, other modifications based on the technical scope of the embodiments of the present disclosure may be applied to other communication systems, such as LTE, LTE-A, and LTE-A-Pro systems.

[0243] Although the present disclosure has been described with various embodiments, various changes and modifications may occur to those skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.

Claims

1. A method performed by a user equipment UE in a wireless communication system, the method include: Receiving logged minimization of drive tests (MDT) configuration information including a list of at least one non-public network (NPN) identifier; performing logged MDT on the independent non-public network SNPN based on the logged MDT configuration information; identifying whether an identity of a SNPN selected or registered by the UE matches the list of at least one NPN identity; transmitting, in case the identity of the SNPN selected or registered by the UE matches the list of the at least one NPN identity, an availability indicator to a base station BS indicating that the result of the logged MDT is stored in the UE; receiving a UE information request message from the BS; as well as In response to the UE information request message, a UE information response message including a result of the logged MDT for the SNPN is transmitted to the BS.

2. The method of claim 1, wherein the result of the logged MDT comprises an identification of the SNPN on which the UE resides or an identification of the SNPN selected by the UE, or an identification of the SNPN registered by the UE, wherein executing the logged MDT further include: Identify whether a radio link failure (RLF) has occurred. The UE information request message includes an RLF report request message, The UE information response message includes a RLF report, and The RLF report includes an identifier of the SNPN on which the UE resides or an identifier of the SNPN selected by the UE, or an identifier of the SNPN registered by the UE.

3. The method according to claim 1, further comprising: include: UE capability information is transmitted to the BS, the UE capability information including information for instructing the UE to report at least one of a logged MDT report or a radio link failure RLF report.

4. The method of claim 2, wherein the recorded MDT configuration information further includes group identifier GIN information for network selection, and The UE information response message further includes at least one result of the logged MDT collected based on the GIN information.

5. A method performed by a base station BS in a wireless communication system, the method include: receiving, from a user equipment UE, an availability indicator indicating that a result of the logged MDT is stored in the UE, if the identity of the independent non-public network SNPN associated with the BS matches a list of at least one non-public network NPN identity configured for the UE; Based on the availability indicator, transmitting a UE information request message to the UE; as well as A UE information response message including a result of the logged MDT for the SNPN is received from the UE as a response to the UE information request message.

6. The method of claim 5, wherein the result of the logged MDT comprises an identification of the SNPN on which the UE resides or an identification of the SNPN selected by the UE, or an identification of the SNPN registered by the UE, The UE information request message includes a radio link failure (RLF) report request message, The UE information response message includes a RLF report, and The RLF report includes an identifier of the SNPN on which the UE resides or an identifier of the SNPN selected by the UE, or an identifier of the SNPN registered by the UE.

7. The method according to claim 5, further comprising: include: UE capability information is received from the UE, the UE capability information including information for indicating the UE to report at least one of a logged MDT report or a radio link failure (RLF) report.

8. The method of claim 5, wherein the UE information response message further includes at least one result of the logged MDT collected based on group identifier GIN information for network selection, and The GIN information is included in logged MDT configuration information used by the UE to perform the logged MDT.

9. A user equipment UE in a wireless communication system, the UE include: transceiver, and A controller is connected to the transceiver and is configured to: Receiving logged minimization of drive tests (MDT) configuration information including a list of at least one non-public network (NPN) identifier; performing logged MDT on the independent non-public network SNPN based on the logged MDT configuration information; identifying whether an identity of a SNPN selected or registered by the UE matches the list of at least one NPN identity; transmitting, in case the identity of the SNPN selected or registered by the UE matches the list of the at least one NPN identity, an availability indicator to a base station BS indicating that the result of the logged MDT is stored in the UE; receiving a UE information request message from the BS; as well as In response to the UE information request message, a UE information response message including a result of the logged MDT for the SNPN is transmitted to the BS.

10. The UE of claim 9, wherein the result of the logged MDT comprises an identification of the SNPN on which the UE resides or an identification of the SNPN selected by the UE, or an identification of the SNPN registered by the UE, The controller is further configured to: Identify whether a radio link failure (RLF) has occurred. The UE information request message includes an RLF report request message, The UE information response message includes a RLF report, and The RLF report includes an identifier of the SNPN on which the UE resides or an identifier of the SNPN selected by the UE, or an identifier of the SNPN registered by the UE.

11. The UE according to claim 9, wherein the controller is further configured to: UE capability information is transmitted to the BS, the UE capability information including information for instructing the UE to report at least one of a logged MDT report or a radio link failure RLF report.

12. The UE according to claim 9, wherein the logged MDT configuration information further includes group identifier GIN information for network selection, and The UE information response message further includes at least one result of the logged MDT collected based on the GIN information.

13. A base station BS in a wireless communication system, the BS include: transceiver, and A controller is connected to the transceiver and is configured to: receiving, from a user equipment UE, an availability indicator indicating that a result of the logged MDT is stored in the UE, if the identity of the independent non-public network SNPN associated with the BS matches a list of at least one non-public network NPN identity configured for the UE; Based on the availability indicator, transmitting a UE information request message to the UE; as well as A UE information response message including a result of the logged MDT for the SNPN is received from the UE as a response to the UE information request message.

14. The BS of claim 13, wherein the result of the logged MDT comprises an identity of the SNPN on which the UE is camped or an identity of the SNPN selected by the UE, or an identity of the SNPN registered by the UE, The UE information request message includes a radio link failure (RLF) report request message, The UE information response message includes a RLF report, and The RLF report includes an identifier of the SNPN on which the UE resides or an identifier of the SNPN selected by the UE, or an identifier of the SNPN registered by the UE.

15. The BS of claim 13, wherein the controller is further configured to: UE capability information is received from the UE, the UE capability information including information for indicating the UE to report at least one of a logged MDT report or a radio link failure (RLF) report.

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