Methods and apparatus for controlling access in next-generation mobile communication systems

Abstract

An apparatus and method for applying a 5G communication system to an IoT network are provided. The apparatus includes technologies such as sensor networks, machine-type communication (MTC), and machine-to-machine (M2M) communication, which can be implemented through beamforming, multiple-input multiple-output (MIMO), and array antennas. Cloud radio access network (RAN), as an application of the aforementioned big data processing technologies, can also be considered an example of the convergence between 5G and IoT technologies. This disclosure relates to methods and apparatus for controlling network access in next-generation mobile communication systems.

Description

[0001] This case is a divisional application of the invention patent application filed on August 3, 2018, with application number 201880050623.6 and title "Method and apparatus for controlling access in a next-generation mobile communication system". Technical Field

[0002] This disclosure relates to methods and apparatus for controlling access in a next-generation mobile communication system. More specifically, this disclosure relates to a receiver-triggered packet data convergence protocol (PDCP) status reporting method in a next-generation mobile communication system. Background Technology

[0003] To meet the increasing demand for wireless data services since the deployment of fourth-generation (4G) communication systems, efforts have been made to develop improved fifth-generation (5G) or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "super-4G networks" or "post-Long Term Evolution (LTE) systems." 5G communication systems are considered to be implemented in higher-frequency millimeter-wave (mmWave) bands (e.g., the 60GHz band) to achieve higher data rates. To reduce radio wave propagation loss and increase transmission distance, beamforming, massive MIMO (Multiple-Input Multiple-Output), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive MIMO technologies are discussed in 5G communication systems. In addition, in 5G communication systems, the development of system network improvements based on advanced small cells, radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multi-point (CoMP), and receiver interference cancellation is underway. In 5G systems, hybrid frequency-shift keying (FSK) and quadrature amplitude (QAM) modulation, frequency and quadrature amplitude modulation (FQAM), and sliding window superposition coding (SWSC) are used as advanced coding modulation (ACM). Filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) have also been developed as advanced access technologies.

[0004] The Internet, a human-centric network in which humans generate and consume information, is now evolving into the Internet of Things (IoT), in which distributed entities, such as things, exchange and process information without human intervention. The Internet of Everything (IoE), combining IoT technology and big data processing technology through connections to cloud servers, has emerged. With the increasing demand for technological elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology in IoT implementation, sensor networks, machine-to-machine (M2M) communication, and machine-type communication (MTC) have recently been explored. This IoT environment can provide intelligent Internet technology services, creating new value for human life by collecting and analyzing data generated between interconnected things. Through the integration and combination of existing information technology (IT) and various industrial applications, IoT can be applied to a wide range of fields, including smart homes, smart buildings, smart cities, smart or connected cars, smart grids, healthcare, smart appliances, and advanced medical services.

[0005] Consistent with this, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, MTC, and M2M communication can be implemented through beamforming, MIMO, and array antennas. Cloud radio access networks (RAN), as an application of the aforementioned big data processing technologies, can also be considered an example of the convergence between 5G and IoT technologies.

[0006] The above information is presented as background information only to aid in understanding this disclosure. No determination or assertion is made regarding whether any of the above constitutes an application of the prior art of this disclosure. Summary of the Invention

[0007] [Technical Issues]

[0008] The present disclosure addresses at least the aforementioned problems and / or disadvantages, and provides at least the advantages described below. Therefore, one aspect of the present disclosure is to provide a method and apparatus for controlling access in a next-generation mobile communication system.

[0009] Another aspect of this disclosure is to provide a method and apparatus for controlling access to a terminal.

[0010] Additional aspects will be set forth in part in the description which follows, and in part will be obvious from the description or may be learned by practice of the presented embodiments.

[0011] Furthermore, this disclosure specifies the portions of the packet delay tolerance report to be modified for use in wireless communication systems (LTE systems), and details the procedures required to apply the packet delay tolerance report to next-generation mobile communication systems. The packet delay tolerance report is used to adjust Discontinuous Reception (DRX) to improve LTE Voice over LTE (VoLTE) performance and enhance data (Physical Uplink Shared Channel (PUSCH)) transmission to extend coverage. For example, a terminal sends an RRC report message to request the DRX period and retransmission time period, thereby improving the delay tolerance level and extending coverage based on the current VoLTE call quality.

[0012] In next-generation mobile communication systems supporting high data rates, if a PDCP PDU is lost or delayed in a single-connectivity environment, if a PDCP PDU is discarded at the transmitter due to the expiration of a PDCP expiration timer, or if one of the two PDCP entities delays receiving a PDCP PDU in a dual-connectivity environment, all received data should be stored in a buffer until the reordering timer triggered at the receive PDCP layer expires, resulting in transmission delays. Therefore, the terminal must have a large-capacity memory or buffer to store all data received during the reordering timer's runtime. Insufficient memory or buffer capacity can lead to data loss. If data for which a PDCP reordering timer has been triggered arrives before the timer expires, or if the PDCP reordering timer expires, a large amount of data received during the timer's runtime may be transmitted to the upper layer all at once, potentially overwhelming the upper layer and causing data loss.

[0013] [Problem Solving]

[0014] According to one aspect of this disclosure, an access control method for a terminal in a wireless communication system is provided. The method includes: if access is triggered, checking the access type of the triggered access, and determining the access type of the triggered access as a predetermined access category based on the checked access type.

[0015] Preferably, determining the access type of the triggered access as the access category includes: determining whether the detected access type is an emergency access type, and if the detected access type is an emergency access type, determining the triggered access type as a first access category related to the emergency access type.

[0016] Preferably, the method further includes determining whether the triggered access type is an operator-providing service access type if the detected access type is not an emergency access type, and determining the triggered access type as a second access category related to the operator-providing service access type if the triggered access type is an operator-providing service access type.

[0017] Preferably, the method further includes determining the triggered access type as a third access category if the detected access type is not an access type provided by the operator.

[0018] Preferably, the method further includes receiving information from the operator's server about a second access category related to the access type provided by the operator.

[0019] Preferably, the method further includes receiving information about an access category list from a base station, and determining the access type of the triggered access as a predetermined access category, including determining the access type of the triggered access based on the detected access type and the information about the access category list.

[0020] Preferably, the method further includes determining whether to perform triggered access based on the determined access category, and if it is determined that triggered access should be performed, sending a connection request message to the base station.

[0021] According to another aspect of this disclosure, a terminal for a wireless communication system is provided. The terminal includes a transceiver and at least one processor configured to: if access is triggered, check the access type of the triggered access, and determine the access type of the triggered access as a predetermined access category based on the checked access type.

[0022] Preferably, the at least one processor is configured to control: determine whether the detected access type is an emergency access type, and if the detected access type is an emergency access type, determine the triggered access type as a first access category associated with the emergency access type.

[0023] Preferably, the at least one processor is configured to control: if the detected access type is not an emergency access type, to determine whether the triggered access type is an access type provided by the operator, and if the triggered access type is an access type provided by the operator, to determine the triggered access type as a second access category associated with the access type provided by the operator.

[0024] Preferably, the at least one processor is configured to control the triggering of an access type as a third access category if the detected access type is not the type of access provided by the operator.

[0025] Preferably, the at least one processor is configured to control the transceiver to receive information from the operator server regarding a second access category related to the access type provided by the operator.

[0026] Preferably, the at least one processor is configured to control the transceiver to receive information about the access category list from the base station, and the access type of the triggered access is determined based on the detected access type and the information about the access category list.

[0027] Preferably, the at least one processor is configured to control the transceiver to: determine whether to perform triggered access based on the determined access category, and if it is determined that triggered access should be performed, control the transceiver to send a connection request message to the base station.

[0028] Preferably, the at least one processor is configured to determine whether to execute the triggered access based on the determined access category and the triggered access type.

[0029] Other aspects, advantages, and distinctive features of this disclosure will become apparent to those skilled in the art from the following detailed description of various embodiments disclosed in conjunction with the accompanying drawings.

[0030] According to one aspect of this disclosure, a method is provided performed by a user equipment (UE) in a communication system supporting dual connectivity, the method comprising: identifying a delay budget report indicating a preferred value for discontinuous reception of DRX; identifying that transmission of the delay budget report has been initiated; and sending UE auxiliary information including the delay budget report to a first base station, wherein the delay budget report is for a long DRX period length associated with the primary cell group (MCG) of the first base station, and wherein the secondary cell group (SCG) of a second base station is aggregated with the UE's MCG.

[0031] According to one aspect of this disclosure, a method is provided performed by a base station in a communication system supporting dual connectivity, the method comprising: sending a Radio Resource Control (RRC) message to a User Equipment (UE) including parameters associated with Discontinuous Reception (DRX); and, upon initiation of delay budget report transmission, receiving from the UE UE assisted information including a delay budget report indicating a preferred value of DRX, wherein the delay budget report is used for a long DRX period length associated with the primary cell group (MCG) of a first base station, and wherein the secondary cell group (SCG) of a second base station is aggregated with the UE's MCG.

[0032] According to one aspect of this disclosure, a user equipment (UE) is provided in a dual-connectivity communication system, the UE comprising: a transceiver; and a controller coupled to the transceiver and configured to: recognize a delay budget report indicating a preferred value for discontinuous DRX reception, recognize that transmission of the delay budget report is initiated, and transmit UE auxiliary information including the delay budget report to a first base station, wherein the delay budget report is for a long DRX period length associated with the primary cell group (MCG) of the first base station, and wherein the secondary cell group (SCG) of a second base station is aggregated with the UE's MCG.

[0033] According to one aspect of this disclosure, a base station is provided in a communication system supporting dual connectivity, the base station comprising: a transceiver; and a controller coupled to the transceiver and configured to: send a Radio Resource Control (RRC) message to a User Equipment (UE) including parameters associated with Discontinuous Reception (DRX); and, upon initiation of delay budget report transmission, receive from the UE UE assisted information including a delay budget report indicating a preferred value of DRX, wherein the delay budget report is used for a long DRX period length associated with the primary cell group (MCG) of a first base station, and wherein the secondary cell group (SCG) of a second base station is aggregated with the UE's MCG.

[0034] [Beneficial effects of the invention]

[0035] As stated above, this disclosure is advantageous in facilitating network access in next-generation mobile communication systems.

[0036] Furthermore, the access control method disclosed herein is advantageous in improving system throughput by effectively controlling UE access.

[0037] Furthermore, the PDCP status reporting method disclosed herein is advantageous in addressing transmission delays and data loss caused by a reordering timer running at the receiver. Specifically, the receiver triggers a PDCP status report and sends the PDCP status report to the transmitter when a predetermined timer running at the receiving PDCP layer expires, when the amount of data stored in the receive buffer becomes equal to or greater than a threshold, or when the reordering timer value reaches a predetermined time. The transmitter receives and examines the PDCP status report to discard the data successfully received by the receiver (PDCP PDU or PDCP SDU) and quickly retransmits the lost data.

[0038] Furthermore, the UE-assisted packet delay budget reporting method of this disclosure is advantageous in clarifying the operation of the UE and gNB by modifying and explicitly defining the operations used in legacy LTE systems. Moreover, the UE-assisted packet delay budget reporting method of this disclosure is advantageous in its applicability to next-generation mobile communication systems. Attached Figure Description

[0039] The above and other aspects, features, and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0040] Figure 1A This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure;

[0041] Figure 1B This is a diagram illustrating a method for determining whether to accept access in a conventional Long Term Evolution (LTE) system according to an embodiment of the present disclosure;

[0042] Figure 1C This is a diagram illustrating the process of performing Application Specific Congestion Control for Data Communication (ACDC) operation in a conventional LTE system according to an embodiment of the present disclosure;

[0043] Figure 1D This is a diagram illustrating the structure of ACDC configuration information used in a conventional LTE system according to an embodiment of the present disclosure;

[0044] Figure 1E This is a diagram illustrating the process of UE access control operation according to an embodiment of the present disclosure;

[0045] Figure 1F This is a flowchart illustrating the operation of a user equipment (UE) non-access stratum (NAS) according to an embodiment of this disclosure;

[0046] Figure 1G This is a signal flow diagram illustrating the access control process according to an embodiment of the present disclosure;

[0047] Figure 1H This is a flowchart illustrating UE NAS operation according to Embodiment 2 of this disclosure;

[0048] Figure 1I This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure;

[0049] Figure 1J This is a block diagram illustrating the configuration of a novel radio Node B (gNB) according to an embodiment of the present disclosure;

[0050] Figure 2A This is a signal flow diagram illustrating the access control process according to an embodiment of the present disclosure;

[0051] Figure 2B This is a flowchart illustrating UE NAS operation according to embodiment 2-1 of this disclosure;

[0052] Figure 2C This is a flowchart illustrating the operation of the UE AS according to Embodiment 2-1 of this disclosure;

[0053] Figure 2D This is a flowchart illustrating UE NAS operation according to Embodiment 2-2 of this disclosure;

[0054] Figure 2E This is a flowchart illustrating the operation of the UE AS according to Embodiment 2-2 of this disclosure;

[0055] Figure 2F This is a signal flow diagram according to embodiments of the present disclosure for providing various types of prohibition configuration information for access control to a UE from a network.

[0056] Figure 3A This is a signal flow diagram illustrating the process for providing system information in a next-generation mobile communication system according to embodiments of the present disclosure;

[0057] Figure 3B This is a signal flow diagram illustrating the random access process in a conventional LTE system according to embodiments of the present disclosure;

[0058] Figure 3C This is a flowchart illustrating a process for selecting one of a system information (SI) request method based on msg1 and an SI request message based on msg3, according to an embodiment of the present disclosure.

[0059] Figure 3D This is a signal flow diagram illustrating the service request processing procedure in the process of requesting system information according to Embodiment 3-1 of this disclosure;

[0060] Figure 3E This is a signal flow diagram illustrating the process of processing a service request during the process of requesting system information according to Embodiment 3-2 of this disclosure;

[0061] Figure 4A This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure;

[0062] Figure 4B This is a diagram illustrating a method for determining whether to accept access in a conventional LTE system according to an embodiment of the present disclosure;

[0063] Figure 4C This is a diagram illustrating a process for performing AC / DC operation in a conventional LTE system according to an embodiment of the present disclosure;

[0064] Figure 4DThis is a diagram illustrating the structure of ACDC configuration information used in a conventional LTE system according to an embodiment of the present disclosure;

[0065] Figure 4E This is a diagram illustrating the process of UE access control operation according to an embodiment of the present disclosure;

[0066] Figure 4F This is a signal flow diagram illustrating the access control process according to an embodiment of the present disclosure;

[0067] Figure 4G This is a diagram illustrating a method for configuring access prohibition configuration information according to an embodiment of the present disclosure;

[0068] Figure 4H This is a flowchart illustrating the operation of a UE NAS according to an embodiment of the present disclosure;

[0069] Figure 4I This is a flowchart illustrating the operation of a UE AS according to an embodiment of this disclosure;

[0070] Figure 4J This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure;

[0071] Figure 4K This is a block diagram illustrating the configuration of a gNB according to an embodiment of the present disclosure;

[0072] Figure 5A This is a diagram illustrating the architecture of an LTE system according to an embodiment of the present disclosure;

[0073] Figure 5B This is a diagram illustrating the protocol stack of the interface between a UE and an eNB in ​​an LTE system according to an embodiment of the present disclosure;

[0074] Figure 5C This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure;

[0075] Figure 5D This is a diagram illustrating the protocol stack of the interface between a New Radio (NR) UE and an NR gNB in ​​a next-generation mobile communication system according to an embodiment of the present disclosure;

[0076] Figure 5E This is a signal flow diagram illustrating the process by which the gNB configures the Packet Data Convergence Protocol (PDCP) Status Report Request function via RRC message when the UE establishes a connection with the network, according to an embodiment of this disclosure;

[0077] Figure 5F This is a diagram illustrating the transmission delay and data loss problem caused by the PDCP reordering timer of the PDCP entity according to an embodiment of this disclosure;

[0078] Figure 5G This is a diagram illustrating the format of a first type of PDCP status report according to an embodiment of this disclosure;

[0079] Figure 5H A flowchart illustrating the operations of a sending PDCP entity and a receiving PDCP entity for processing a proposed PDCP status report according to embodiments of the present disclosure is described;

[0080] Figure 5I This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure;

[0081] Figure 5J This is a block diagram illustrating the configuration of a gNB according to an embodiment of the present disclosure;

[0082] Figure 6A This is a diagram illustrating the architecture of an LTE system according to an embodiment of the present disclosure;

[0083] Figure 6B This is a diagram illustrating the protocol stack of the interface between a UE and an eNB in ​​an LTE system according to an embodiment of the present disclosure;

[0084] Figure 6C This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure;

[0085] Figure 6D This is a diagram illustrating the protocol stack of the interface between an NR UE and an NR gNB in ​​a next-generation mobile communication system according to an embodiment of the present disclosure;

[0086] Figure 6E This is a diagram illustrating the discontinuous reception (DRX) operation of a UE in idle mode in an LTE system according to an embodiment of the present disclosure;

[0087] Figure 6F This is a diagram illustrating the DRX operation of a UE in Radio Resource Control (RRC) connection mode in an LTE system according to an embodiment of the present disclosure;

[0088] Figure 6G This is a diagram illustrating packet delay budget reporting operations for improving the quality of LTE voice (VoLTE) in a wireless communication system according to an embodiment of the present disclosure;

[0089] Figure 6H This is a diagram illustrating a method for measuring packet transmission delay in a VoLTE system according to an embodiment of the present disclosure;

[0090] Figure 6IThis is a signal flow diagram illustrating a method for a UE to request a change in the ConnectedMode Discontinuous Reception (CDRX) cycle and to transmit and receive data in the changed CDRX cycle, according to an embodiment of this disclosure.

[0091] Figure 6J This is a flowchart illustrating the CDRX cycle change process of a UE according to an embodiment of the present disclosure;

[0092] Figure 6K This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure;

[0093] Figure 6L This is a block diagram illustrating the configuration of a gNB according to an embodiment of the present disclosure;

[0094] Figure 7A This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure;

[0095] Figure 7B This is a diagram illustrating a method for determining whether to accept access in a conventional LTE system according to an embodiment of the present disclosure;

[0096] Figure 7C This is a diagram illustrating a process for performing ACDC operation in an LTE system according to an embodiment of the present disclosure;

[0097] Figure 7D This is a diagram illustrating the structure of ACDC configuration information used in an LTE system according to an embodiment of the present disclosure;

[0098] Figure 7E This is a diagram illustrating a process for controlling access of a UE in connected mode or inactive mode according to an embodiment of the present disclosure;

[0099] Figure 7F This is a signal flow diagram illustrating the access control process of a UE in connected mode or inactive mode according to an embodiment of the present disclosure;

[0100] Figure 7G This is a flowchart illustrating the operation of a UE NAS according to an embodiment of the present disclosure;

[0101] Figure 7H This is a flowchart illustrating the operation of a UE AS according to an embodiment of this disclosure;

[0102] Figure 7I This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure; and

[0103] Figure 7J This is a block diagram illustrating the configuration of a gNB according to an embodiment of the present disclosure.

[0104] In all the accompanying drawings, similar reference numerals will be understood to refer to similar parts, components and structures. Detailed Implementation

[0105] The following description, provided with reference to the accompanying drawings, is intended to aid in a comprehensive understanding of the various embodiments of this disclosure as defined by the claims and their equivalents. It includes various specific details to aid understanding, but these are merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the various embodiments described herein without departing from the scope and spirit of this disclosure. Furthermore, for clarity and brevity, descriptions of well-known functions and structures may be omitted.

[0106] The terms and words used in the following description and claims are not limited to their literal meaning, but are used by the inventors only to enable a clear and consistent understanding of this disclosure. Therefore, it will be apparent to those skilled in the art that the following description of various embodiments of this disclosure is for illustrative purposes only and is not intended to limit the disclosure as defined by the appended claims and their equivalents.

[0107] It should be understood that the singular forms “a,” “one,” and “the” include plural referents unless the context clearly indicates otherwise. Thus, for example, a reference to “a component surface” includes a reference to one or more such surfaces.

[0108] The term “substantially” means that it is not necessary to obtain the listed characteristics, parameters or values ​​precisely, but rather that deviations or variations may occur in a quantity that does not exclude the effect that the characteristic is intended to provide, including, for example, tolerances, measurement errors, measurement accuracy limitations and other factors known to those skilled in the art.

[0109] To avoid obscuring the subject matter of this disclosure, detailed descriptions of well-known functions and structures incorporated herein may be omitted. This is intended to omit unnecessary descriptions in order to clarify the subject matter of this disclosure.

[0110] For the same reason, some elements are enlarged, omitted, or simplified in the accompanying drawings, and in practice, these elements may have different dimensions and / or shapes than those shown in the drawings. In all the drawings, the same reference numerals are used to refer to the same or similar parts.

[0111] The advantages and features of this disclosure, as well as methods for achieving these advantages and features, can be more readily understood by referring to the following detailed description of embodiments and accompanying drawings. However, this disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to make the invention thorough and complete, and to fully convey the concept of the invention to those skilled in the art, and this disclosure will be defined only by the appended claims. Throughout the specification, similar reference numerals refer to similar elements.

[0112] It should be understood that each block of a flowchart and / or block diagram, and combinations of blocks in a flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus, such that instructions executed by the processor of the computer or other programmable data processing apparatus create means for implementing the functions / actions specified in the flowchart and / or block diagram. These computer program instructions can also be stored in a non-transitory computer-readable storage medium that can direct the computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the non-transitory computer-readable storage medium produce an article of writing embedding means for implementing the functions / actions specified in the flowchart and / or block diagram. Computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational operations to be performed on the computer or other programmable apparatus, thereby producing a computer-implemented process, such that instructions executing on the computer or other programmable apparatus provide operations for implementing the functions / actions specified in the flowchart and / or block diagram.

[0113] Furthermore, the block diagrams may illustrate modules, segments, or portions of code comprising at least one or more executable instructions for performing a specific logical function(s). It should also be noted that in some modifications, the functions of blocks may be executed in different orders. For example, two consecutive blocks may be executed substantially simultaneously, or they may be executed in reverse order depending on their functions.

[0114] According to various embodiments of this disclosure, the term "module" refers to, but is not limited to, a software or hardware component that performs a particular task, such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC). Modules can advantageously be configured to reside on an addressable memory medium and configured to execute on one or more processors. Thus, as examples, a module may include components (such as software components, object-oriented software components, class components, and task components), processes, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided in components and modules may be combined into fewer components and modules, or further separated into additional components and modules. Furthermore, components and modules may be implemented such that they execute one or more Central Processing Units (CPUs) in a device or secure multimedia card. According to various embodiments of this disclosure, a module may include at least one processor.

[0115] Example 1

[0116] Figure 1A This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure.

[0117] refer to Figure 1A The next-generation mobile communication system's radio access network 1a-20 includes the new radio Node B (NRNB) 1a-10 and the new radio core network (NR CN) 1a-05. New radio user equipment (hereinafter referred to as new radio user equipment (NR UE) or simply UE) 1a-15 connects to external networks via NR NB 1a-10 and NR CN 1a-05.

[0118] exist Figure 1AIn this context, NR NB 1a-10 corresponds to the evolved Node B (eNB) in a traditional LTE system. NR UE 1a-15 connects to the NR NB, which can provide services superior to those of a traditional eNB. In next-generation mobile communication systems where all user services are served through a shared channel, entities are needed to collect UE-specific state information (such as buffer status, power margin status, and channel status) and schedule UEs based on the collected information; NR NB 1a-10 is responsible for these functions. Typically, one NR NB carries multiple cells. To meet the higher data rate requirements of traditional LTE, it is necessary to employ advanced technologies (such as Orthogonal Frequency Division Multiplexing (OFDM) as a radio access scheme and beamforming) to ensure a wider maximum bandwidth than before. Adaptive Modulation and Coding (AMC) techniques can be used to determine the modulation scheme and channel coding rate to adapt to the UE's channel conditions. NR CN 1a-05 is responsible for mobility management, bearer establishment, and QoS establishment. NR CN1a-05 is responsible for other control functions and UE mobility management functions associated with multiple NR NBs. Next-generation mobile communication systems can interoperate with legacy LTE systems by connecting NR CN 1a-05 to the Mobility Management Entity (MME) 1a-25 via a network interface. The MME 1a-25 is connected to the eNB 1a-30, which acts as a legacy base station.

[0119] Figure 1B This is a diagram illustrating a method for determining whether to accept access in a conventional LTE system according to an embodiment of the present disclosure.

[0120] refer to Figure 1BTypically, the functions of an LTE UE are divided into Access Stratum (AS) 1b-15 and Non-Access Stratum (NAS) 1b-05. The AS is responsible for all access-related functions, while the NAS is responsible for non-access-related functions such as Public Land Mobile Network (PLMN) selection and service requests. Accessibility determination can be primarily made by the UE AS. As mentioned above, a congested network can restrict new access, and for this purpose, it broadcasts relevant configuration information so that each UE can make its own access determination, as shown in reference numeral 1b-35. With the introduction of new requirements in legacy LTE systems, new prohibition mechanisms have been proposed, resulting in allowing multiple access prohibition checks. If the UE NAS layer issues a service request, as shown in reference numeral 1b-10, the UE AS checks whether the UE can actually access the network. If the establishment reason value of the service request is "delay-tolerant access," the UE AS first performs an Extended Access Barring (EAB), as shown in reference numeral 1b-20. The EAB prohibition mechanism is performed as an access check procedure applicable only to Machine Type Communication (MTC). If the EAB check passes, the UE AS performs dedicated congestion control (ACDC) for data communication, as shown in reference numeral 1b-55. The application requesting service is assigned an ACDC category, the value of which can be included in the service request transmitted to the UE AS. The network can provide prohibition configuration information for each ACDC category. Therefore, the access check process can be performed in groups, categorized by ACDC category. If the prohibition configuration information for each ACDC category is not provided by the network, the UE AS omits the ACDC access check process. If the ACDC check passes, the UE AS performs Access Class Barring (ACB), as shown in reference numeral 1b-30. ACB is an access check process that uses prohibition configuration information provided separately based on Mobile Originating (MO) data or MO signaling. For multiple telephony (MMTEL) voice / video / SMS services, the ACB process can be omitted using an ACB skip indicator, as shown in reference numeral 1b-25. If all the above access checks pass, the UE AS can attempt to access the network. For example, the UE AS performs random access and sends a Radio Resource Control (RRC) Connection Request message to the eNB, as shown in Figure 1b-40. There may be another access check procedure not performed by the UE AS.If a SSAC (Service-Suppressed Configuration Message) for MMTEL voice / video is received from the network, as shown in Figure 1b-45, the UE AS transmits this message to the IMS (Integrated Management System) layer responsible for managing services within the UE, as shown in Figure 1b-50. Upon receiving the SSAC, the IMS layer can perform an access check procedure when the service is triggered. SSAC was introduced with the intention of enabling the UE AS to perform corresponding functions regardless of the application or service type. Therefore, to control the determination of whether to accept access to a specific service (such as MMTEL voice / video), it is necessary to transmit the SSAC directly to the layer managing that service so that the corresponding layer can perform the access check procedure.

[0121] In next-generation mobile communication systems, such a complex process is unnecessary. This is because it is possible to design a single access check procedure that incorporates all the requirements introduced in LTE from the outset. This disclosure proposes a single prohibition mechanism evolved from the traditional ACDC access check procedure.

[0122] Figure 1C This is a diagram illustrating the process of performing ACDC operation in a conventional LTE system according to an embodiment of the present disclosure.

[0123] refer to Figure 1C In traditional LTE systems, ACDC (Advanced Access Control) has been proposed to determine accessibility for each application (service). Each application is assigned at least one ACDC category value. The ACDC category value is selected from a range of 1 to 16. At Operation 1c-25, Network 1c-20 provides the ACDC category information for each application to UE NAS 1c-10 using NAS messages. At Operation 1c-50, Network 1c-20 provides UE AS1c-15 with prohibition configuration information to be applied to each ACDC category using System Information Block 2 (SIB2). The prohibition configuration information includes the ac-BarringFactor Information Element (IE) and the ac-Barringtime IE. The value of ac-BarringFactor α is in the range of 0 ≤ α < 1. UE AS1c-15 extracts a random value of rand within the range of 0 ≤ rand < 1; if the random value is less than ac-BarringFactor, access is assumed to be not prohibited; otherwise, access is assumed to be prohibited. If access is determined to be denied, the UE AS1c-15 will delay the access attempt for a duration based on the following equation.

[0124] "Tbarring"(0.7+0.6*rand)*ac-BarringTime. Equation 1

[0125] If a service request is triggered, at operation 1c-30, UE AS1c-15 extracts the ACDC category value corresponding to the application for that service. At operation 1c-35, UE NAS1c-10 sends a service request including the ACDC category value to UE AS1c-15. Upon receiving the service request, at operation 1c-40, UE AS1c-15 determines whether access is accepted based on the ACDC category value and the ACDC prohibition configuration information included in SIB2. If SIB2 does not include prohibition configuration information corresponding to the ACDC category, it is assumed that the application belonging to that ACDC category is allowed access during the ACDC process. If access is allowed through the access prohibition check process, at operation 1c-45, UE AS1c-15 sends an RRC connection request for random access to the network.

[0126] Figure 1D This is a diagram illustrating the structure of ACDC configuration information used in a conventional LTE system according to an embodiment of the present disclosure.

[0127] refer to Figure 1D The ACDC configuration information (ACDC-BarringForCommon-r13) 1d-10 can provide PLMN-specific prohibition configuration information sets (ACDC-BarringPerPLMN 1, ACDC-BarringPerPLMN 2, ...) 1d-35 and 1d-40. If all PLMNs have the same prohibition configuration information set, a single prohibition configuration information set (ACDC-BarringForCommon-r13) 1d-05 can be set most broadly. PLMN-specific or common prohibition configuration information sets include category-specific prohibition configuration information 1d-20, 1d-25, and 1d-30. As mentioned above, prohibition configuration information 1d-45 includes ac-BarringFactor IE and ac-Barringtime IE. If there is no prohibition configuration information for a specific ACDC category, it is assumed that applications belonging to the corresponding ACDC category are not prohibited by ACDC.

[0128] Figure 1E This is a diagram illustrating the process of UE access control operation according to an embodiment of the present disclosure.

[0129] refer to Figure 1EThis disclosure proposes a category-based access control scheme similar to traditional ACDC. However, the proposed access control scheme differs from traditional ACDC in that the classification is performed using other elements and applications, such as service access type, call type, UE class, user group, signaling type, slice type, and any combination thereof. For example, access control can be performed on specific access types for certain elements. In this disclosure, access is classified into two categories. One category is a standardized access category. This category is defined at the RAN level, i.e., explicitly classified in standard documents. In this disclosure, the emergency-related category belongs to the standard access category. Each access belongs to at least one standardized access category. The other is a non-standardized access category. This category is defined outside the 3rd Generation Partnership Project (3GPP) architecture and therefore is not explicitly classified in standard documents. This is similar to the characteristics of categories in traditional ACDC. However, a specific access triggered by UE NAS may not be mapped to a non-standardized access category. The operator's server 1e-25 provides non-standardized category information to UE NAS1e-10 via NAS signaling or application layer data transmission. Non-standardized category information provides a mapping between non-standardized categories and classification elements (such as applications). The new radio Node B (gNB) 1e-20 uses system information to provide the UE with a list of categories containing prohibition configuration information and prohibition configuration information for each category. UE AS1e-15 sends the list of categories provided by gNB 1e-20 to UE NAS 1e-10. UE NAS1e-10 maps triggered access to one of the categories according to predetermined rules. UE NAS1e-10 sends information about the mapped categories and a service request to UE AS1e-15. UE AS1e-15 determines whether to allow access triggered by UE NAS1e-10 based on the prohibition configuration information (prohibition check).

[0130] Example 1-1

[0131] This disclosure proposes a method for mapping access triggered by UE NAS to a specific category. In Example 1-1, UE NAS maps access to a category.

[0132] In Embodiment 1-1, access is mapped to at least one standardized access category. Furthermore, access may not be mapped to any subcategory of a non-standardized access category provided by the network. In this disclosure, the categories provided by the network to which access is mapped are assigned at least one predetermined priority. Triggered access is mapped to the category with the highest priority among the categories to which the access can be mapped. In this disclosure, the category corresponding to "emergency" belongs to the set of categories with the highest priority. The category corresponding to "high-priority access" may belong to the set of categories with the highest priority. High-priority access represents access dedicated to mobile communication operators or public officials, such as access for police and firefighters. It corresponds to the traditional LTE Access Class (AC) 11 to 15. All categories belonging to non-standardized access categories belong to the second high-priority category set. Except for emergency and high-priority access, all categories belonging to standardized access categories belong to the third high-priority category set.

[0133] For example, UE NAS maps triggered access to categories, as shown below.

[0134] [Operation 1] The UE NAS determines whether the triggered access can be mapped to one of the following standardized access categories. The following categories have the highest priority.

[0135] -urgent

[0136] -High-priority access (AC 11~15)

[0137] If there is no category to which the access can be mapped among the standardized access categories provided by the network, the process proceeds to operation 2.

[0138] [Operation 2] The UE NAS determines whether the triggered access can be mapped to one of the following non-standard access categories. All non-standard access categories have the second highest priority.

[0139] -application

[0140] -UE type, user group

[0141] -Service Access Type

[0142] -Call Type

[0143] -Signaling type

[0144] - Slice type

[0145] -The combination of the above elements

[0146] If there is no non-standard access category that the access can be mapped to among the non-standard access categories provided by the network, the process proceeds to operation 3.

[0147] [Operation 3] The UE NAS determines whether the triggered access can be mapped to one of the standardized access categories other than those considered in Operation 1. All standardized access categories have the third highest priority, except for those with the highest priority. All accesses belong to at least one standardized access category.

[0148] Figure 1F This is a flowchart illustrating the operation of a UE NAS according to an embodiment of the present disclosure.

[0149] refer to Figure 1F At operation 1f-02, the UE NAS receives information about the non-standardized access categories supported in the network via NAS signaling or application layer signaling. This information includes information about the mapping between categories and elements. For example, this information may include information about the mapping between categories and applications.

[0150] At operation 1f-05, the UE NAS receives an access category list from the UE AS, which provides prohibition configuration information in the system information sent by the gNB. At operation 1f-10, the UE NAS triggers access. At operation 1f-15, the UE NAS determines whether access can be mapped to one of the categories with the highest priority. Categories with the highest priority include those corresponding to "urgent" or "high-priority access". If it is determined that access can be mapped to one of the categories with the highest priority, then at operation 1f-20, the UE NAS maps the access to the corresponding category. If it is determined that access cannot be mapped to one of the categories with the highest priority, then at operation 1f-25, the UE NAS determines whether the access can be mapped to one of the non-standardized access category information received from the network at operation 1f-02 and the non-standardized access category included in the list provided by the gNB at operation 1f-05. If it is determined that access can be mapped to one of the non-standardized access categories, then at operation 1f-30, the UE NAS maps the access to the corresponding category. If it is determined that access cannot be mapped to one of the non-standardized access categories, then at operation 1f-35, the UE NAS maps the access to one of the standardized access categories. At operation 1f-40, the UE NAS sends a service request message to the UE AS including the mapped category.

[0151] Examples 1-2

[0152] In embodiments 1-2, the UE NAS maps access to a standardized access class, and additionally, to a non-standardized access class to which that access can be mapped. In this disclosure, the service request sent by the UE NAS to the UE AS includes information indicating a standardized access class, because the triggered access should be mapped to a standardized access class. At operation 1f-05, the UE AS does not provide a list of access classes. Therefore, the operation at operation 1f-25 determining whether access can be mapped to one of the non-standardized access classes is not performed based on non-standardized access classes included in the list. For example, the UE NAS determines the existence of a non-standardized access class solely based on information about network-supported non-standardized access classes provided via NAS signaling or application layer signaling.

[0153] In Examples 1-2, the UE NAS can send both a standardized access category and a non-standardized access category to the UE AS. In this case, the UE AS selects one of the standardized and non-standardized access categories to use the prohibition configuration information corresponding to the selected access category. If the prohibition configuration information associated with both the mapped standardized and non-standardized access categories is broadcast by the gNB, the UE NAS uses the prohibition configuration information corresponding to the non-standardized access category to perform an access prohibition check. If the prohibition configuration information associated with the non-standardized access category is not broadcast by the gNB, the UE NAS uses the prohibition configuration information corresponding to the standardized access category to perform an access prohibition check. If neither the prohibition configuration information associated with the mapped standardized access category nor the prohibition configuration information associated with the mapped non-standardized access category is broadcast by the gNB, the UE NAS does not perform an access prohibition check and assumes access is allowed. However, there is an exception. If the mapped standardized access category corresponds to "urgent" or "high-priority access" with the highest priority, if the prohibition configuration information regarding the category is broadcast by the gNB, and if the prohibition configuration information indicates that access is allowed, the mapped non-standardized access category provided along with the mapped standardized access category is not considered. For example, access is allowed.

[0154] Figure 1G This is a signal flow diagram illustrating the access control process according to an embodiment of the present disclosure.

[0155] refer to Figure 1GAt Operation 1g-25, Network 1g-20 sends information about its supported non-standardized access categories to UE NAS1g-10 via NAS signaling or application layer signaling. This information includes a mapping between categories and elements. For example, this information may include information about the mapping between categories and applications. At Operation 1g-30, UE NAS triggers access. At Operation 1g-35, the UE maps the access to a standardized access category. If the information received from the network includes information about non-standardized access categories to which the access can be mapped, the UE maps the access to one of the non-standardized access categories. At Operation 1g-45, UE NAS sends a service request to UE AS1g-15 including the mapped categories. For example, at Operation 1g-45, UE NAS may notify UE AS1g-15 of only standardized access categories or both standardized and non-standardized access categories. At Operation 1g-40, gNB provides the UE with prohibition configuration information for each category using system information. Prohibition configuration information is not mandatory for all categories.

[0156] UE AS1g-15 determines whether access is allowed based on predetermined rules.

[0157] Referring to Operation 1g-50, if the mapped standardized access category corresponds to either "urgent" or "high priority access", if the category's prohibition configuration information is provided by the gNB, and if the prohibition configuration information indicates access permission, then access is assumed to be permitted.

[0158] Otherwise, if the prohibition configuration information for the mapped non-standard access category is provided by the gNB, the UE AS1g-15 determines whether access is permitted based on the corresponding prohibition information.

[0159] If the access does not correspond to either "urgent" or "high priority access", and if the prohibition configuration information for the mapped standardized access category is provided by the gNB for access that is not mapped to any non-standardized access category, then the UE AS1g-15 applies the prohibition configuration information to determine whether access is allowed.

[0160] The UE AS1g-15 determines whether access is allowed, and if so, sends a connection request message to the gNB at Operation 1g-55.

[0161] Figure 1H This is a flowchart illustrating UE NAS operation according to Embodiment 2 of this disclosure.

[0162] refer to Figure 1HAt operation 1h-05, the UE NAS receives information about the non-standardized access categories supported in the network, provided via NAS signaling or application layer signaling. This information includes information about the mapping between categories and elements. For example, this information may include information about the mapping between categories and applications.

[0163] At operation 1h-10, the UE NAS triggers access. At operation 1h-15, the UE NAS maps the access to one of the standardized access categories. At operation 1h-20, if possible, the UE NAS maps the access to a non-standardized access category. If there is no non-standardized access category to which the access can be mapped among those notified at operation 1h-05, the non-standardized access category may not be notified to the UE AS. At operation 1h-25, the UE NAS notifies the UE AS of the mapped category.

[0164] Figure 1I This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure.

[0165] refer to Figure 1I The UE includes a radio frequency (RF) processor 1i-10, a baseband processor 1i-20, a storage unit 1i-30, and a controller 1i-40.

[0166] The RF processor 1i-10 has the function of transmitting / receiving signals through a radio channel, such as frequency band conversion and amplification of signals. For example, the RF processor 1i-10 up-converts a baseband signal from the baseband processor 1i-20 into an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back into a baseband signal. For example, the RF processor 1i-10 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), and an analog-to-digital converter (ADC). Although only one antenna is depicted in the figures, the UE may be equipped with multiple antennas. The RF processor 1i-10 may also include multiple RF chains. The RF processor 1i-10 can perform beamforming. For beamforming, the RF processor 1i-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. The RF processor 1i-1 can be configured to support a multiple-input multiple-output (MIMO) scheme, which allows the UE to receive signals from multiple layers simultaneously.

[0167] The baseband processor 1i-20 has baseband signal-to-bit string conversion capabilities according to the system's physical layer standard. For example, in data transmission mode, the baseband processor 1i-20 encodes and modulates the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 1i-20 demodulates and decodes the baseband signal from the RF processor 1i-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 1i-20 encodes and modulates the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs an inverse fast Fourier transform (IFFT) on the symbols, and inserts a cyclic prefix (CP) into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 1i-20 divides the baseband signal from the RF processor 1i-10 into OFDM symbols, performs a Fast Fourier Transform (FFT) on the OFDM symbols to recover the signal mapped to the subcarrier, and performs demodulation and decoding on the signal to recover the transmitted bit string.

[0168] The baseband processor 1i-20 and RF processor 1i-10 process transmitted and received signals as described above. Therefore, the baseband processor 1i-20 and RF processor 1i-10 can be referred to as a transmitter, receiver, transceiver, or communication unit. At least one of the baseband processor 1i-20 and RF processor 1i-10 may include multiple communication modules for supporting different radio access technologies. At least one of the baseband processor 1i-20 and RF processor 1i-10 may also include multiple communication modules for processing signals in different frequency bands. For example, different radio access technologies may include Wireless Local Area Network (WLAN) (e.g., Institute of Electrical and Electronics Engineers (IEEE) 802.11) and cellular networks (e.g., LTE). Different frequency bands may include super high frequency (SHF) bands (e.g., 2.5 GHz and 5 GHz bands) and mmWave bands (e.g., 60 GHz).

[0169] Storage unit 1i-30 stores data, such as basic procedures, applications, and settings information for operating the UE. Storage unit 1i-30 can also store information about a second access node that uses a second radio access technology for radio communication. Storage unit 1i-30 provides the stored information in response to requests from controller 1i-40.

[0170] Controller 1i-40 includes a multi-connection processor 1i-42 and controls the overall operation of the UE. For example, controller 1i-40 controls baseband processor 1i-20 and RF processor 1i-10 to transmit and receive signals. Controller 1i-40 writes data to and reads data from storage unit 1i-30. For this purpose, controller 1i-40 may include at least one processor. For example, controller 1i-40 may include a communication processor (CP) for controlling communications and an application processor (AP) for controlling higher-level programs (such as applications).

[0171] Figure 1J This is a block diagram illustrating the configuration of a novel radio Node B (gNB) according to an embodiment of this disclosure.

[0172] refer to Figure 1J The gNB includes an RF processor 1j-10, a baseband processor 1j-20, a backhaul communication unit 1j-30, a storage unit 1j-40, and a controller 1j-50.

[0173] RF processor 1j-10 has the function of transmitting / receiving signals through a radio channel, such as frequency band conversion and amplification of signals. For example, RF processor 1j-10 up-converts a baseband signal from baseband processor 1j-20 to an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back to a baseband signal. For example, RF processor 1j-10 may include transmit filters, receive filters, amplifiers, mixers, oscillators, DACs, and ADCs. Although one antenna is depicted in the figures, the gNB may be equipped with multiple antennas. RF processor 1j-10 may also include multiple RF chains. RF processor 1i-10 can perform beamforming. For beamforming, RF processor 1j-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. RF processor 1j-10 can be configured to transmit one or more layers of downlink MIMO operation.

[0174] The baseband processor 1j-20 has baseband signal-to-bit string conversion functionality according to the system's physical layer standard. For example, in data transmission mode, the baseband processor 1j-20 performs encoding and modulation on the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 1j-20 performs demodulation and decoding on the baseband signal from the RF processor 1j-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 1j-20 performs encoding and modulation on the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs inverse IFFT on the symbols, and inserts CP into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 1j-20 divides the baseband signal from the RF processor 1j-10 into OFDM symbols, performs FFT on the OFDM symbols to recover the signal mapped to the subcarriers, and performs demodulation and decoding on the signals to recover the transmitted bit string. The baseband processor 1j-20 and the RF processor 1j-10 process the transmitted and received signals as described above. Therefore, the baseband processor 1j-20 and the RF processor 1j-10 can be referred to as transmitters, receivers, transceivers, or communication units.

[0175] The backhaul communication unit 1j-30 provides an interface for communicating with other nodes in the network. For example, the backhaul communication unit 1j-30 converts bit strings to be sent from the gNB to another node (e.g., another gNB and the core network) into physical signals, and converts physical signals received from another node into bit strings.

[0176] Storage unit 1j-40 stores data such as basic procedures, application programs, and setting information for gNB operation. Storage unit 1j-40 can also store information about bearers established for the UE and measurement results reported by connected UEs. Storage unit 1j-40 can also store information used by the UE when determining whether to enable or disable multiple connections. Storage unit 1j-40 can provide stored data based on requests from controller 1j-50.

[0177] The controller 1j-50 includes a multi-connection processor 1j-52 and controls the overall operation of the gNB. For example, the controller 1j-50 controls the baseband processor 1j-20, the RF processor 1j-10, and the backhaul communication unit 1j-30 for transmitting and receiving signals. The controller 1j-50 reads and writes data to the storage unit 1j-40. For this purpose, the controller 1j-50 may include at least one processor.

[0178] Example 2

[0179] Figure 2A This is a signal flow diagram illustrating the access control process according to an embodiment of the present disclosure.

[0180] refer to Figure 2A At operation 2a-25, network 2a-20 sends information about its supported non-standardized access categories to UE NAS2a-10 via NAS signaling or application layer signaling. This information includes a mapping between categories and elements. For example, this information may include information about the mapping between categories and applications. At operation 2a-30, the UE maps the establishment reason value corresponding to the access to the access category. The establishment reason value is included in the initial message sent to the gNB for the connection request and is used by the gNB to make an access prohibition determination. At operation 2a-50, the gNB sends prohibition configuration information for each category to the UE via system information. Not all categories are required to provide prohibition configuration information.

[0181] At Operation 2a-35, the UE NAS notifies the UE AS2a-15 to map to the access category of the determined establishment reason value.

[0182] At operation 2a-40, UE AS2a-15 determines whether access is permitted according to predetermined rules.

[0183] If access is granted, then at operation 2a-45, UE AS2a-15 sends a connection request message to gNB.

[0184] In this disclosure, establishment reason values ​​are mapped one-to-one to standardized access categories. Standardized access categories are used for access denial. Standardized access categories include at least one category corresponding to "urgent" and "high-priority access," and each category is used to indicate the establishment reason value. In this disclosure, connection request messages may include standardized access category information (index values) instead of establishment reason values. In conventional LTE technologies, the following establishment reason values ​​are used.

[0185] -emergency

[0186] -highPriorityAccess

[0187] -mt-Access,

[0188] -mo-Signalling

[0189] -mo-Data,

[0190] -delayTolerantAccess

[0191] -mo-VoiceCall

[0192] According to embodiments of this disclosure, the establishment reason value has a corresponding standardized access category, as shown below:

[0193] -emergency(Access Category 0),

[0194] -highPriorityAccess (Access Category 1)

[0195] -mt-Access (Access Category 2),

[0196] -mo-Signalling (Access Category 3),

[0197] -mo-Data (Access Category 4),

[0198] -delayTolerantAccess (Access Category 5)

[0199] -mo-VoiceCall (Access Category 6)

[0200] Example 2-1

[0201] In Example 2-1, if there is any non-standardized access class that can be mapped to, the UE NAS notifies the UE AS2a-15 of both the non-standardized access class and the standardized access class to be mapped.

[0202] Figure 2B This is a flowchart illustrating UE NAS operation according to Embodiment 2-1 of this disclosure.

[0203] refer to Figure 2B At operation 2b-05, the UE NAS receives information about the non-standardized access categories supported in the network, provided via NAS signaling or application layer signaling. At operation 2b-10, the UE NAS triggers access. At operation 2b-15, the UE NAS maps the access to a standardized access category. At operation 2b-20, the UE NAS determines whether the access can be mapped to a non-standardized access category. If the access can be mapped to a non-standardized access category, the category corresponding to that access should be included in the non-standardized access categories notified at operation 2b-05. If a non-standardized access category exists to which the access can be mapped, at operation 2b-25, the UE NAS sends a service request to the UE AS including both the mapped standardized and non-standardized access categories. If no non-standardized access category exists to which the access can be mapped, at operation 2b-30, the UE NAS sends a service request to the UE AS including only the mapped standardized access category. Sending a standardized access category to the UE AS has the same meaning as sending an establishment cause value to the UE AS, because standardized access categories are mapped one-to-one to establishment cause values.

[0204] Figure 2C This is a flowchart illustrating the operation of a UE AS according to Embodiment 2-1 of this disclosure.

[0205] refer to Figure 2C At operation 2c-05, the UE AS receives a service request from the UE NAS and determines whether the service request includes a standardized access class (or establishment reason value) or both a standardized access class and a non-standardized access class. If the service request is determined to include only the standardized access class, at operation 2c-10, the UE AS determines whether to allow access to the requested service based solely on the prohibition configuration information corresponding to the standardized access class. If access is determined to be allowed, the UE AS sends an RRC Connection Request message to the gNB. If the prohibition configuration information corresponding to the standardized access class is not included in the system information broadcast by the gNB, the UE AS assumes access is allowed. At operation 2c-15, the UE AS includes a standardized access class value (index value) or an establishment reason value corresponding to the standardized access class in the RRC Connection Request message sent to the gNB. If the service request is determined to include both the standardized access class and a non-standardized access class, at operation 2c-20, the UE AS determines whether to first allow access to the requested service based on the prohibition configuration information corresponding to the non-standardized access class. If the prohibition configuration information corresponding to the non-standardized access category is not included in the system information broadcast by the gNB, the UE AS determines whether access will be permitted based on the prohibition configuration information corresponding to the standardized access category. If neither the prohibition configuration information corresponding to the non-standardized access category nor the prohibition configuration information corresponding to the standardized access category is included in the system information broadcast by the gNB, the UE AS assumes access is permitted. At operation 2c-25, the UE AS includes the standardized category value (index value) or establishment reason value corresponding to the standardized access category in the RRC connection request message sent to the gNB.

[0206] Example 2-2

[0207] In Example 2-2, if there are any non-standardized access categories to which access can be mapped, the UE NAS only notifies the UE AS of the mapped non-standardized access categories.

[0208] Figure 2D This is a flowchart illustrating UE NAS operation according to Embodiment 2-2 of this disclosure.

[0209] refer to Figure 2DAt operation 2d-05, the UE NAS receives information about the non-standardized access categories supported in the network, provided via NAS signaling or application layer signaling. At operation 2d-10, the UE NAS triggers access. At operation 2d-15, the UE NAS maps the access to a standardized access category. At operation 2d-20, the UE NAS determines whether the access can be mapped to a non-standardized access category. If the access can be mapped to a non-standardized access category, the category corresponding to that access should be included in the non-standardized access categories provided at operation 2d-05. If a non-standardized access category exists to which the access can be mapped, at operation 2d-25, the UE NAS sends a service request to the UE AS including the mapped non-standardized access category. If no non-standardized access category exists to which the access can be mapped, at operation 2d-30, the UE NAS sends a service request to the UE AS including the mapped standardized access category. Sending a standardized access category to the UE AS has the same meaning as sending an establishment cause value to the UE AS, because standardized access categories are mapped one-to-one to establishment cause values.

[0210] Figure 2E This is a flowchart illustrating the operation of a UE AS according to Embodiment 2-2 of this disclosure.

[0211] refer to Figure 2EAt Operation 2e-05, the UE AS receives a service request from the UE NAS and determines whether the service request includes a standardized access class (or establishment reason value) or a non-standardized access class. If the service request is determined to include only a standardized access class, at Operation 2e-10, the UE AS determines whether to allow access to the requested service based solely on the prohibition configuration information corresponding to the standardized access class. If access is determined to be allowed, the UE AS sends an RRC connection request message to the gNB. If the prohibition configuration information corresponding to the standardized access class is not included in the system information broadcast by the gNB, the UE AS assumes access is allowed. At Operation 2e-15, the UE AS includes the standardized access class value (index value) or establishment reason value corresponding to the standardized access class in the RRC connection request message sent to the gNB. If the service request is determined to include only a non-standardized access class, at Operation 2e-20, the UE AS determines whether to allow access to the requested service based on the prohibition configuration information corresponding to the non-standardized access class. If the prohibition configuration information corresponding to a non-standardized access category is not included in the system information broadcast by the gNB, the UE AS determines whether to allow access based on the prohibition configuration information corresponding to a standardized access category. At Operation 2e-25, since the UE NAS does not notify any standardized access category, the UE AS must autonomously determine the appropriate standardized access category based on the non-standardized access category. If neither the prohibition configuration information corresponding to a non-standardized access category nor the prohibition configuration information corresponding to a standardized access category is included in the system information broadcast by the gNB, the UE AS assumes access is allowed. At Operation 2c-30, the UE AS includes a standardized category value (index value) or establishment reason value corresponding to the standardized access category in the RRC connection request message sent to the gNB.

[0212] Figure 2F This is a signal flow diagram according to embodiments of the present disclosure for providing various types of prohibition configuration information for access control to a UE from a network.

[0213] refer to Figure 2FAt operation 2f-15, gNB 2f-10 sends prohibition configuration information to UE 2f-05 using system information. This disclosure proposes a method for effectively configuring prohibition configuration information. As described above, prohibition configuration information can be provided for each access category. Here, prohibition configuration information corresponding to the "emergency" access category has a BOOLEAN format. For example, a 1-bit information is used to indicate whether access to emergency services is permitted. Prohibition configuration information corresponding to the "high priority access" access category has a BOOLEAN or bitmap format. "High priority access" means mobile operator-dedicated or public security-dedicated access. In cases where multiple types of dedicated links may exist, a bitmap format is used to indicate whether each of the dedicated links is permitted access. For example, a 5-bit map can be used, where the first bit indicates whether mobile operator-dedicated links are permitted access, and the second bit indicates whether police-exclusive links are permitted access. The information carried by predetermined bits of the bitmap may only be valid in a specific country or PLMN. For example, the first and last bits of a 5-bit map may be valid in the home PLMN / equivalent PLMN (HPLMN / EPLMN), while the second, third, and fourth bits may be valid in the home country. Bitmap information can be provided to indicate whether access to the "high-priority access" service is allowed for each category. For example, bitmap information can be included in the prohibition configuration information for each category to indicate whether access to the "high-priority access" service is allowed for each category.

[0214] The prohibition configuration information corresponding to standardized and non-standardized access categories includes ac-BarringFactor IE and ac-Barringtime IE. The value of ac-BarringFactor α is in the range of 0 ≤ α < 1. UE AS1c-15 extracts a random value of rand in the range of 0 ≤ rand < 1; if the random value is less than ac-BarringFactor, access is assumed to be not prohibited, and if not, access is assumed to be prohibited. If access is determined to be prohibited, the UE AS will delay the access attempt for a duration derived from a predetermined equation. For example, the delay duration can be calculated according to the following equation.

[0215] "Tbarring"(0.7+0.6*rand)*ac-BarringTime.

[0216] In this disclosure, if a mobile communication operator wants to allow 100% access to services belonging to a specific standardized access category, all it needs to do is not provide the prohibition configuration information corresponding to that category.

[0217] Mobile communication operators may want to allow 100% access to services belonging to a specific non-standardized access category. However, although no prohibition configuration information corresponding to the category is provided as in the case of a standardized access category, this disclosure first utilizes prohibition configuration information corresponding to the standardized access category to perform access prohibition checks. Therefore, it is difficult to allow access as expected with 100% permission. Therefore, an indicator is needed to indicate whether access associated with a specific non-standardized access category is 100% permitted. This disclosure proposes a 1-bit indicator in the prohibition configuration information for the corresponding category to indicate whether to skip the prohibition check for that category.

[0218] In LTE Rel-11 EAB technology, the prohibition configuration information for MTC devices applies to specific UE groups. Table 1 shows the relevant ASN.1 taken from 3GPP TS36.331.

[0219] [Table 1]

[0220]

[0221]

[0222] In Table 1, eab-Category represents the category of UEs to which EAB applies. Value a corresponds to all UEs, value b corresponds to UEs that are neither in their HPLMN nor in a PLMN equivalent to their HPLMN, and value c corresponds to UEs that are neither in the PLMN of the country in which the UE is roaming, nor in their HPLMN, nor in a PLMN equivalent to their HPLMN, as defined in the PLMN selector list by the operator on the USIM, see TS 22.011

[10] .

[0223] The eab-Category IE is used to indicate which of the three categories of groups to which the prohibition configuration information is applied. In next-generation mobile communication systems, prohibition configuration information can be applied to each access category in a similar manner. In this disclosure, access category-specific prohibition configuration information includes information indicating a group of UEs to which the configuration information is applied. UEs can be divided into three groups.

[0224] 1) Group 1: All UEs

[0225] 2) Group 2: UEs that are neither in their HPLMN nor in a PLMN equivalent to their HPLMN.

[0226] 3) Group 3: UEs that are neither listed in the operator-defined PLMN selector list on the USIM as the preferred PLMN of the country the UE is roaming in, nor in their HPLMN, nor in a PLMN equivalent to their HPLMN.

[0227] Example 3

[0228] Figure 3A This is a signal flow diagram illustrating the process used to provide system information in next-generation mobile communication systems.

[0229] refer to Figure 3A In next-generation mobile communication systems, the system information broadcast by gNB 3a-10 is divided into minimum system information (SI) and other SIs. At Operation 3a-15, gNB 3a-10 periodically broadcasts the minimum SI, which includes configuration information required for initial access and SI scheduling information required for UE 3a-05 to receive other SIs broadcast periodically or in response to requests. Typically, other SIs include all configuration information not included in the minimum SI. At Operation 3a-20, other SIs are broadcast periodically or in response to requests from UE 3a-05, or at Operation 3a-25, they are sent to UE 3a-05 via dedicated signaling. When other SIs are sent in response to requests from UE 3a-05, UE 3a-05 needs to determine whether the other SI is valid in the serving cell or is being broadcast (in response to a request from another UE). This determination can be based on specific information included in the minimum SI. UEs in idle mode (RRC_IDLE) or inactive mode (RRC_INACTIVE) can request other SIs without requiring an RRC state transition. UEs in connected mode (RRC_CONNECTED) can request and receive other SIs via dedicated RRC signaling. Other SIs are broadcast at predetermined intervals within a time period. Public Warning System (PWS) information is provided as part of other SIs. Whether other SIs are broadcast or sent to the UE via RRC signaling depends on the network implementation.

[0230] Figure 3B This is a signal flow diagram illustrating the random access process in a traditional LTE system.

[0231] refer to Figure 3BThe system performs random access to achieve uplink synchronization and send data to the network. Random access can be performed for mode switching from idle mode to connected mode, RRC reconstruction, handover, and uplink / downlink data transmission. If UE 3b-05 receives a dedicated preamble from gNB 3b-10, it performs the random access procedure by sending the dedicated preamble to gNB 3b-10. Otherwise, UE 3b-05 selects one of two preamble groups and then randomly selects a preamble from the selected group. These two groups are referred to as group A and lease B. If the channel quality state is greater than a threshold, and if the size of msg3 is greater than a threshold, UE 3b-05 selects a preamble from group A; if these conditions are not met, UE 3b-05 selects a preamble from group B. At operation 3b-15, UE 3b-05 sends the selected preamble in the nth subframe. If the preamble is transmitted in the nth subframe, the Random Access Response (RAR) window begins in the (n+3)th subframe, causing UE 3b-05 to monitor the RAR window for receiving the RAR at operation 3b-20. RAR scheduling information can be indicated using the Random Access Radio Network Temporary Identifier (RA-RNTI) of the Physical Downlink Control Channel (PDCCH). The RA-RNTI is derived based on the radio resource location in the time-frequency domain used for preamble transmission. The RAR includes a Timing Advance Command, UL grant, and a temporary cell RNTI (C-RNTI). If the RAR is successfully received within the RAR window, at operation 3b-25, UE 3b-05 transmits msg3 based on the information included in the UL grant contained in the RAR. msg3 includes different information depending on the purpose of random access. Table 2 illustrates examples of information that may be included in msg3.

[0232] [Table 2]

[0233]

[0234]

[0235] If a RAR is received in the nth subframe, UE 3b-05 sends msg3 in the (n+6)th subframe. The Hybrid Automatic Repeat Request (HARQ) procedure begins with msg3. Upon sending msg3, UE 3b-05 starts a predetermined timer and monitors for a Contention Resolution (CR) message at operation 3b-30 until the timer expires. Depending on the purpose of the random access, in addition to the CR Media Access Control (MAC) control element (CE), the CR message may also include an RRC connection establishment or RRC connection re-establishment message.

[0236] Figure 3C This is a flowchart illustrating a process for selecting one of a system information (SI) request method based on msg1 and an SI request message based on msg3, according to an embodiment of the present disclosure.

[0237] refer to Figure 3C To request other SIs, the UE performs a random access procedure. The UE can use msg1 (preamble) or msg3 to request the required system information from the network. At operation 3c-05, the UE determines whether the minimum SI periodically broadcast by the gNB includes information about the Physical Random Access Channel (PRACH) resources used to request the SI. The PRACH resource information may include the preamble ID (prach-ConfigIndex) used to request the SI and information about the radio resources used to transmit the preamble. If the minimum SI is determined to include PRACH resource information, at operation 3c-10, the UE can use msg1, dedicated to SI requests, to request other SIs. If the minimum SI is determined not to include PRACH resource information, at operation 3c-15, the UE can use msg3 to request other SIs. A new RRC message is defined for requesting SIs.

[0238] Example 3-1

[0239] In Example 3-1, if a service request is triggered before a predetermined time point during the random access procedure in which the UE requests system information from the gNB, the UE sends an RRC connection request or RRC connection resumption request message indicating system information, which is used for the service request. In this case, it is not necessary to define a new RRC message for the system information request.

[0240] Figure 3D This is a signal flow diagram illustrating the service request processing procedure in the process of requesting system information according to Embodiment 3-1 of this disclosure.

[0241] refer to Figure 3D At operation 3d-15, UE 3d-05 receives system information from gNB 3d-10. This system information may include random access configuration information required for an SI request based on msg1. If the system information does not include the random access configuration information required for an SI request based on msg1, then at operation 3d-20, UE 3d-05 triggers an SI request based on msg3. At operation 3d-25, UE 3d-05 triggers a random access procedure for the SI request purpose by sending a preamble. At operation 3d-30, UE 3d-05 receives a RAR from gNB 1d-10, and at operation 3d-45, sends an RRC message to gNB 3d-10 using msg3, which is newly defined for the SI request. At operation 3d-35, during the random access procedure, UE 3d-05 may trigger a service request before sending msg3. Service requests can be triggered by a UE NAS in idle mode or a UE AS in inactive mode. At operation 3d-40, instead of a new RRC message defined for a system information request, the UE sends msg3 carrying an RRC connection request message in idle mode or an RRC connection recovery request message in inactive mode. This RRC connection request or RRC connection recovery request message includes an indicator indicating the requested system information (i.e., an SI message or SIB).

[0242] If gNB 3d-10 receives an RRC connection request message from UE 3d-05, it generates msg4 at operation 3d-50, which includes the UE CR identifier MAC CE and the RRC connection establishment message.

[0243] If gNB 3d-10 receives an RRC connection restoration request message from UE 3d-05, it generates msg4 at operation 3d-50, which includes the UE CR identifier MAC CE and the RRC connection restoration message.

[0244] If gNB 3d-10 receives a new RRC message defined for a system information request from UE 3d-05, then at operation 3d-50, it generates msg4 which includes the UE CR identifier MAC CE.

[0245] At operation 3d-55, gNB 3d-10 sends msg4 to UE 3d-05.

[0246] If gNB 3d-10 receives an RRC connection request or RRC connection restoration request message from UE 3d-05, which is one of the new RRC messages defined for SI requests and includes an indicator indicating the requested system information, then gNB 3d-10 sends the system information indicated by that indicator to UE 3d-05 according to the schedule. The scheduling information is provided to gNB 3d-10 in advance via the minimum SI.

[0247] If a service request is triggered after sending msg3 carrying a system information request message, UE 3d-05 triggers a separate random access procedure to handle the access corresponding to the service request. If the random access procedure for the service request is in progress, UE 3d-05 can request system information by sending msg3 carrying an RRC connection request message in idle mode or an RRC connection recovery request message in inactive mode. This RRC message includes an indicator indicating a request for system information (i.e., an SI message or SIB).

[0248] Example 3-2

[0249] In Example 3-2, if a service request is triggered before a predetermined time point during the random access procedure during which the UE requests system information from the gNB, the UE prioritizes processing the service request. Typically, the configuration information required for network access is included in the minimum SI. Therefore, it is possible to perform the random access procedure without needing to request other SIs as described above. Furthermore, considering the user, it is preferable to prioritize processing the service request over obtaining system information. Although the random access procedure is performed to request system information, msg3 carries an RRC connection request or RRC connection resumption request message for the service request. The UE suspends the system information request and resumes it if the service request has been fully processed.

[0250] Figure 3E This is a signal flow diagram illustrating the process of processing a service request during the request for system information according to Embodiment 3-2 of this disclosure.

[0251] refer to Figure 3EAt Operation 3e-15, UE 3e-05 receives system information from gNB 3e-10. The system information may include random access configuration information required for an SI request based on msg1. If the system information does not include the random access configuration information required for an SI request based on msg1, then at Operation 3e-20, UE 3e-05 triggers an SI request based on msg3. At Operation 3e-25, UE 3e-05 triggers a random access procedure for the SI request purpose by sending a preamble. At Operation 3e-30, UE 3e-05 receives a RAR from gNB 1e-10. UE 3e-05 sends an RRC message including an indicator indicating the requested SI to gNB 3e-10 via msg3, based on the UL authorization included in the RAR. During the random access procedure, UE 3e-05 may trigger a service request before sending msg3. At Operation 3e-35, a service request can be triggered by a UE NAS in idle mode or a UE AS in inactive mode. At Operation 3e-40, the UE sends msg3 carrying an RRC connection request message in idle mode or an RRC connection recovery request message in inactive mode, instead of the new RRC message defined for system information requests.

[0252] If gNB 3e-10 receives an RRC connection request message from UE 3e-05, it generates msg4, which includes the UE CR identifier MAC CE and the RRC connection establishment message.

[0253] If gNB 3e-10 receives an RRC connection restoration request message from UE 3e-05, it generates msg4, which includes the UECR identifier MAC CE and the RRC connection restoration message.

[0254] At operation 3d-45, gNB 3e-10 sends msg4 to UE 3e-05.

[0255] If a service request is triggered after sending msg3 carrying a system information request message, UE 3e-05 triggers a separate random access procedure to handle the access corresponding to that service request. If the random access procedure for the service request is in progress, UE 3e-05 does not request system information.

[0256] According to another embodiment of this disclosure, the gNB can send configuration information to the UE such that when a service request is triggered before a predetermined time point during a random access procedure in which the UE requests system information from the gNB, the UE selects one of the system information request and the service request for priority processing. To achieve this, the gNB can configure a 1-bit indicator in the minimum SI to indicate the request to be prioritized.

[0257] Fourth embodiment

[0258] To avoid obscuring the subject matter of this disclosure, detailed descriptions of well-known functions and structures incorporated herein may be omitted. Embodiments of this disclosure are described with reference to the accompanying drawings.

[0259] Figure 4A This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure.

[0260] refer to Figure 4A The radio access network for the next-generation mobile communication system includes the new radio Node B (gNB) 4a-10 and the new radio core network (AMF) 4a-05. The new radio user equipment (hereinafter referred to as NR UE or simply UE) 4a-15 connects to the external network via gNB 4a-10 and AMF 4a-05.

[0261] exist Figure 4A In this context, gNB 4a-10 corresponds to the evolved Node B (eNB) in a traditional LTE system. NR UE 4a-15 connects to a gNB that can provide services superior to those of a traditional eNB. In next-generation mobile communication systems where all user traffic is served through a shared channel, entities are needed to collect UE-specific state information (such as buffer status, power margin status, and channel status) and schedule UEs based on the collected information; gNB 4a-10 is responsible for these functions. Typically, a gNB carries multiple cells. To meet the higher data rate requirements of traditional LTE, it is necessary to employ advanced technologies (such as Orthogonal Frequency Division Multiplexing (OFDM) as a radio access scheme and beamforming) to ensure a wider maximum bandwidth than before. Adaptive modulation and coding (AMC) techniques can be used to determine the modulation scheme and channel coding rate to suit the UE's channel conditions. AMF 4a-05 is responsible for mobility management, bearer establishment, and QoS establishment. AMF 4a-05 is also responsible for other control functions and UE mobility management functions associated with multiple gNBs. The next-generation mobile communication system can interoperate with legacy LTE systems by connecting the AMF 4a-05 to the Mobility Management Entity (MME) 4a-25 via a network interface. The MME 4a-25 connects to the eNB 4a-30, which acts as a legacy base station. UEs supporting LTE-NR dual connectivity can establish connections to the eNB 4a-30, as shown in the attached diagram 4a-35, and to the gNB 4a-10, as shown in the attached diagram 4a-20.

[0262] Figure 4B This is a diagram illustrating a method for determining whether to accept access in a conventional LTE system according to an embodiment of the present disclosure.

[0263] refer to Figure 4ATypically, the functions of an LTE UE are divided into Access Layer (AS) 4b-15 and NAS 4b-05. The AS is responsible for all access-related functions, while NAS 4b-05 is responsible for non-access-related functions, such as Public Land Mobile Network (PLMN) selection and service requests. Accessibility determination can be primarily made by the UE AS. As mentioned above, a congested network can restrict new access, and for this purpose, it broadcasts relevant configuration information so that each UE can make its own access determination, as shown in reference numeral 4b-35. With the introduction of new requirements in legacy LTE systems, new prohibition mechanisms have been proposed, resulting in allowing multiple access prohibition checks. If the UE NAS layer issues a service request, as shown in reference numeral 4b-10, the UE AS checks whether the UE can actually access the network. If the establishment reason value of the service request is "delay-tolerant access," the UE AS first performs an Extended Access Prohibition (EAB), as shown in reference numeral 4b-20. The EAB prohibition mechanism is performed as an access check procedure applicable only to Machine Type Communication (MTC). If the EAB check passes, the UE AS performs dedicated congestion control (ACDC) for data communication, as shown in reference numeral 4b-20. The application requesting service is assigned an ACDC category, the value of which can be included in the service request transmitted to the UE AS, as shown in reference numeral 4b-55. The network can provide prohibition configuration information for each ACDC category. Therefore, the access check procedure can be performed on a per-group basis, categorized by ACDC category. If the prohibition configuration information for each ACDC category is not provided by the network, the UE AS omits the ACDC access check procedure. If the ACDC check passes, the UE AS performs access level prohibition (ACB), as shown in reference numeral 4b-30. ACB is an access check procedure using prohibition configuration information provided separately based on Mobile Initiated (MO) data or MO signaling. For Multi-Telephone (MMTEL) voice / video / SMS services, the ACB procedure can be omitted using an ACB skip indicator, as shown in reference numeral 4b-25. If all the above access checks pass, the UE AS can attempt to access the network. For example, the UE AS performs random access and sends a Radio Resource Control (RRC) Connection Request message to the eNB, as shown in reference numerals 4b-40. There may be another access check procedure not performed by the UE AS. If a Voice / Video Disabled Configuration Message (SSAC) is received from the network, as shown in reference numerals 4b-45, the UE AS forwards this message to the IMS layer responsible for managing services within the UE, as shown in reference numerals 4b-50. After receiving the Disabled Configuration Message, the IMS layer can perform the access check procedure when a service is triggered. SSAC was introduced with the UE AS designed to perform the corresponding function, regardless of the application or service type.Therefore, in order to control the determination of whether to accept access to a specific service (such as MMTEL voice / video), it is necessary to transmit the prohibition configuration information directly to the layer that manages the service so that the corresponding layer can perform the access check process.

[0264] In next-generation mobile communication systems, such a complex process is unnecessary. This is because it is possible to design a single access check procedure that incorporates all the requirements introduced in LTE from the outset. This disclosure proposes a single prohibition mechanism evolved from the traditional ACDC access check procedure.

[0265] Figure 4C This is a diagram illustrating the process of performing ACDC operation in a conventional LTE system according to an embodiment of the present disclosure.

[0266] refer to Figure 4C In traditional LTE systems, ACDC (Advanced Access Control) has been proposed to determine accessibility for each application (service). Each application is assigned at least one ACDC category value. The ACDC category value is selected from a range of 1 to 16. At Operation 4c-25, Network 4c-20 provides the ACDC category information for each application to UE NAS 4c-10 using NAS messages. At Operation 4c-50, Network 4c-20 provides the prohibition configuration information to be applied to each ACDC category to UE AS 4c-15 using System Information Block 2 (SIB2). The prohibition configuration information includes the ac-BarringFactor Information Element (IE) and the ac-Barringtime IE. The value of ac-BarringFactor α is in the range of 0 ≤ α < 1. UE AS 4c-15 extracts a random value of rand within the range of 0 ≤ rand < 1; if the random value is less than ac-BarringFactor, access is assumed to be not prohibited; otherwise, access is assumed to be prohibited. If access is determined to be denied, the UE AS 4c-15 will delay the access attempt for a duration based on the following equation.

[0267] "Tbarring"(0.7+0.6*rand)*ac-BarringTime. Equation 2

[0268] If a service request is triggered, at operation 4c-30, UE AS 4c-15 extracts the ACDC category value corresponding to the application for that service. At operation 4c-35, UE NAS 4c-10 sends a service request including the ACDC category value to UE AS 4c-15. Upon receiving the service request, at operation 4c-40, UE AS 4c-15 determines whether access is accepted based on the ACDC prohibition configuration information included in SIB2 and the ACDC category value. If SIB2 does not include prohibition configuration information corresponding to the ACDC category, it is assumed that the application belonging to that ACDC category is allowed access during the ACDC process. If access is allowed through the access prohibition check process, at operation 4c-45, UE AS 4c-15 sends an RRC connection request for random access to the network.

[0269] Figure 4D This is a diagram illustrating the structure of ACDC configuration information used in a conventional LTE system according to an embodiment of the present disclosure.

[0270] refer to Figure 4D The ACDC configuration information (ACDC-BarringForCommon-r13) 4d-10 can provide PLMN-specific prohibition configuration information sets (ACDC-BarringPerPLMN 1, ACDC-BarringPerPLMN 2, ...) 4d-35 and 4d-40. If all PLMNs have the same prohibition configuration information set, a single prohibition configuration information set (ACDC-BarringForCommon-r13) 4d-05 can be set most broadly. PLMN-specific or common prohibition configuration information sets include category-specific prohibition configuration information 4d-20, 4d-25, and 4d-30. As mentioned above, prohibition configuration information 4d-45 includes ac-BarringFactor IE and ac-Barringtime IE. If there is no prohibition configuration information for a specific ACDC category, it is assumed that applications belonging to the corresponding ACDC category are not prohibited by ACDC.

[0271] Figure 4E This is a diagram illustrating the process of UE access control operation according to an embodiment of the present disclosure.

[0272] refer to Figure 4EThis disclosure proposes a method for controlling access based on access identifiers and access categories, similar to traditional ACDC methods. Access identifiers are indication information defined in 3GPP standards, i.e., explicitly specified in standard documents. Access identifiers are used to indicate one of several access types, as shown in the table below. They primarily indicate access types classified as Access Class 11 to 15 and high-priority Multimedia Priority Service (MPS) and Mission Critical Service (MCS) services. Access Class 11 to 15 indicate operator-dedicated or public-purpose access.

[0273]

[0274]

[0275] Access categories are divided into two categories. One of these categories is the standardized access category. This category is defined at the RAN level, i.e., explicitly classified in standard documents. Therefore, the same standardized access category applies to different operators. In this disclosure, the emergency-related category belongs to the standard access category. Each access belongs to at least one standardized access category. The other is the non-standardized access category. This category is defined outside the 3GPP architecture and therefore is not explicitly classified in standard documents. Therefore, operators have their own operator-specific access categories with different meanings. This is similar to the characteristics of categories in traditional ACDC. However, a specific access triggered by UE NAS may not be mapped to a non-standardized access category. The proposed access control scheme differs from traditional ACDC in that the classification is performed using other elements and applications, such as service access type, call type, UE class, user group, signaling type, slice type, and any combination thereof. For example, access control can be performed on access types specific to certain elements. The aforementioned access categories are used to indicate specific accesses, as shown in the table below. Access categories 0 to 7 are used to indicate standardized access categories, and access categories 32 to 63 are used to indicate operator-specific access categories.

[0276]

[0277]

[0278] The operator's server 4e-25 provides operator-specific access category information (MO) to the UE NAS1e-10 via NAS signaling or application layer data transmission. This information indicates a corresponding element, such as an application. For example, this information could explicitly indicate that access category 32 corresponds to Facebook application access. The gNB 4e-20 uses system information to provide the UE with a list of categories containing prohibition configuration information and prohibition configuration information for each category. The UE 4e-05 includes logical blocks of NAS 4e-10 and AS4e-15. The UE NAS maps triggered access to one or more access identifiers and an access category according to predetermined rules. Alternatively, access can be mapped to a standardized access category, and additionally, to an operator-specific access category. The UE NAS 4e-10 sends the mapped access identifier and access category, along with a service request, to the UE AS 4e-10. The UE AS 4e-15 determines whether to allow access triggered by the UE NAS 4e-10 based on the prohibition configuration information (prohibition check).

[0279] Providing an access identifier and access class can be considered associated with the establishment reason. In LTE, the UE NAS provides establishment reason information to the UEAS, and the UE sends an RRC connection request message including the establishment reason information to the network. The network determines whether to accept or reject the RRC connection request based on the establishment reason information. The traditional establishment reason information configuration is shown in Table 3.

[0280] [Table 3]

[0281]

[0282] The cause value can be replaced by the access identifier and the standardized access category. For example, in the establishment cause information, highPriorityAccess can be replaced by the access identifier, Emergency can be replaced by Standardized Access Category 2, mt-Access can be replaced by Standardized Access Category 0, mo-Signalling can be replaced by Standardized Access Category 3, mo-Data can be replaced by Standardized Access Category 7, delayTolerantAccess can be replaced by Standardized Access Category 1, and mo-VoiceCall can be replaced by Standardized Access Category 4. If the access attempt is mapped to the access identifier and the standardized access category, it is not necessary to provide the establishment cause information and the service request. However, if the access attempt is mapped to an operator-specific access category instead of a standardized access category, the establishment cause information is still required. Three options are presented in this disclosure.

[0283] In Option 1, access attempts are always mapped to a standard access category, and, if available, to an operator-specific access category. In this case, the UE NAS does not provide establishment reason information to the UE AS. The UE AS includes an establishment reason value corresponding to the access identifier or standardized access category information in the (alternative) RRC connection request message. Alternatively, the access identifier or standardized access category value may be included in the RRC connection request message without substitution.

[0284] In Option 2, the access attempt is mapped to an access class, regardless of whether that access class is a standardized access class or a carrier-specific access class. The UE NAS may selectively provide establishment reason information to the UE AS depending on whether the access attempt is mapped to a standardized access class. For example, if the access attempt is mapped to a standardized access class, the UE NAS does not provide an establishment reason value to the UE AS; if the access attempt is mapped to a carrier-specific access class instead of a standardized access class, the UE NAS provides an establishment reason value to the UE AS.

[0285] In option 3, the access attempt is mapped to an access class, regardless of whether that access class is a standardized access class or an operator-specific access class. If the access attempt is mapped to an operator-specific access class and not to any other access identifier, the UE AS derives the establishment reason value from the operator-specific access class according to a predetermined rule and includes the establishment reason value in the RRC connection request message. For example, the predetermined rule is that all operator-specific access classes correspond to mo-Data for establishment reason information.

[0286] If the access attempt is mapped to a standardized access category, the UE AS includes an establishment reason value corresponding to the access identifier or standardized access category information in the (alternative) RRC connection request message. Alternatively, the access identifier or standardized access category value may be included in the RRC connection request message without substitution.

[0287] If the UE NAS provides an access identifier in any option, the highPriorityAccess value corresponding to that access identifier is included as the establishment reason value in the RRC connection request message. Alternatively, the access identifier value may be included in the RRC connection request message without substitution.

[0288] Operators may wish to allow access to services of a predetermined type corresponding to at least one of access classes 11 to 15. This disclosure is characterized by determining whether access belonging to access classes 11, 12, 13, 14, and 15 is allowed based on the attributes identified by the access class. To achieve this, this disclosure provides a method for configuring prohibition configuration information for access identifiers or access classes. In this disclosure, it is assumed that the access class-specific prohibition configuration information is configured with ac-barringFactor and ac-barringtime, similar to the prohibition configuration information of related technologies such as ACB or ACDC.

[0289] Figure 4F This is a signal flow diagram illustrating the access control process according to an embodiment of the present disclosure.

[0290] refer to Figure 4FUE 4f-05 includes NAS 4f-10 and AS 4f-15. NAS is responsible for operations not directly related to radio access, such as authentication service requests and session management, while AS 4f-15 is responsible for radio access-related operations. At operation 4f-25, network 4f-20 provides MOI to NAS 4f-10 via OAM (Application Layer Data Message) or NAS messages. The MOI indicates an element, such as an application, corresponding to each operator-specific access class. NAS 4f-10 uses the MOI to identify the operator-specific class to which a triggered access is mapped. If a service is triggered, at operation 4f-30, NAS maps the access identifier corresponding to the attributes of that service to an access class. A service can be mapped to none or at least one access identifier. A service can be mapped to an access class. Under the assumption that a service can be mapped to an access class, NAS 4f-10 determines whether the service is mapped to the operator-specific access class provided in the MO. If the service is not mapped to any carrier-specific access class, NAS 4f-10 maps the service to one of the available standardized access classes. Under the assumption that the service can be mapped to multiple access classes, NAS 4f-10 maps the service to both carrier-specific and standardized access classes. However, if the service is not mapped to any carrier-specific access class, NAS 4f-10 maps the service to one of the available standardized access classes. This mapping rule can be applied except for emergency services. At Operation 4f-40, NAS 4f-10 sends a service request to AS 4f-15 including the mapped access identifier and access class. At Operation 4f-35, AS 4f-15 receives prohibited configuration information included in system information broadcast by Network 4f-20. The prohibited configuration information is described below. At Operation 4f-45, AS determines whether the service request is accepted based on the access identifier and access class information that NAS has already mapped to the service and the corresponding mapping configuration information received from Network 4f-20. If the service request is accepted according to the predefined rules, then at operation 4f-50, AS 4f-15 requests network 4f-20 to establish an RRC connection.

[0291] Figure 4G This is a diagram illustrating a method for configuring access prohibition configuration information according to an embodiment of the present disclosure.

[0292] refer to Figure 4G This disclosure proposes a method for allowing a specific type of access in an access corresponding to at least one of access levels 11 to 15. For example, access belonging to access level 11 and attempting to conduct text and voice call services may be allowed.

[0293] In a first embodiment of this disclosure, the network provides individual configuration information corresponding to each access identifier in the form of a bitmap where bits are mapped to predetermined services, such as... Figure 4G As shown in part (a). Services can be categorized as one of text services, voice call services, video call services, etc. In this embodiment of the present disclosure, bits are mapped to services indicated by access categories. Here, access categories can be limited to standardized access categories. In this case, an 8-bit bitmap is generated as prohibition configuration information for each access identifier, since the number of the aforementioned standardized access categories is 8. When configuring the bitmap, certain services corresponding to standardized access categories can be excluded. For example, it can be assumed that standardized access category number 0 corresponding to a Mobile Terminated (MT) service is always allowed access. Under this assumption, bits mapped to such services are not needed in the bitmap. If one of the bits constituting the bitmap is set to "0", it means that the service corresponding to the access category mapped to the corresponding bit is allowed access. If the corresponding bit is set to "1", it means that the corresponding service is not allowed access, or additional prohibition checks are required to make a final decision on whether access is allowed. Access attempts can be mapped to one or more access identifiers, and in this case, if at least one of the bits corresponding to multiple access identifiers is set to "0", it is assumed that the access attempt is allowed.

[0294] In a second embodiment of this disclosure, the network may include information in the form of a bitmap, which includes bits mapped to corresponding access identifiers in the prohibition configuration information for each access class, such as... Figure 4G As shown in section (b). Assume that the prohibition configuration information for each access class includes ac-barringFactor and ac-barringTime, similar to the prohibition configuration information for traditional ACB or ACDC. Since there are 7 active access identifiers in the table above, the bitmap consists of 7 bits. For example, in Figure 4G In part (b), bit b0 corresponds to identifier 1, bit b1 corresponds to identifier 2, bit b2 corresponds to identifier 11, bit b3 corresponds to identifier 12, bit b4 corresponds to identifier 13, bit b5 corresponds to identifier 14, and bit b6 corresponds to identifier 15.

[0295] In a third embodiment of this disclosure, the network provides separate configuration information corresponding to the first and second access identifiers in the form of a bitmap including bits mapped to predetermined services, such as... Figure 4GAs shown in section (c). This configuration information is used by the UE AS when an access attempt corresponds to the first or second access identifier. The first and second access identifiers indicate a multimedia service with priority (Multimedia Priority Service (MPS)) and a dedicated service (Mission Critical Service (MCS)), respectively. Whether access to a service corresponding to the aforementioned access identifier is allowed depends on one of three UE types.

[0296] a) Configure the UE for MPS (or MCS);

[0297] b) UEs configured for MPS (or MCS) and listed in the operator-defined PLMN selector list as the most preferred PLMN of the country the UE is roaming in, or in their HPLMN, or in a PLMN equivalent to their HPLMN;

[0298] c) Configure UEs for MPS (or MCS) and in their HPLMN or in a PLMN equivalent to their HPLMN.

[0299] Therefore, the individual access restriction configuration information is generated in the form of a 3-bit bitmap corresponding to the three types of UEs. Each bit indicates whether access for the corresponding UE is permitted. For example, in Figure 4G In part (c), bit b0 corresponds to a UE configured for MPS (or MCS), bit b1 corresponds to a UE configured for MPS (or MCS) and listed in the operator-defined PLMN selector list as the most preferred PLMN of the country the UE is roaming in, or in their HPLMN, or in a PLMN equivalent to their HPLMN, and bit b2 corresponds to a UE configured for MPS (or MCS) and in their HPLMN, or in a PLMN equivalent to their HPLMN. The UE knows which type it belongs to among the above types.

[0300] UEs indicated by the bitmap information are allowed access. However, UEs not indicated by the bitmap information are denied access, or their access is ultimately tested by using a denial check based on the denial configuration information corresponding to the access category.

[0301] It can be assumed that UEs not indicated by the bitmap information are allowed access. Conversely, UEs indicated by the bitmap information can be denied access, or their access can be ultimately tested by utilizing a denial check based on the denial configuration information corresponding to the access category.

[0302] Individual prohibition configuration information corresponding to the access identifier may include the configuration information proposed in the first and second embodiments. The configuration information proposed in the third embodiment is included in the configuration information of the first or second identifier. It is also possible that prohibition configuration information corresponding to the access category in the second embodiment is included in the configuration information proposed in the third embodiment. Even in this case, the configuration information proposed in the third embodiment applies only to the first or second access identifier. When the prohibition configuration information corresponding to the access category is included in the configuration information proposed as the best solution in the third embodiment, the first and second identifiers have 3 bits corresponding to them. Each bit is used to indicate the type of UE, as described in the third embodiment. Furthermore, the access identifier has 1 bit corresponding to it.

[0303] Figure 4H This is a flowchart illustrating the operation of a UE NAS according to an embodiment of the present disclosure.

[0304] refer to Figure 4H At operation 4h-05, the UE NAS receives the MOI from the network via OAM or RRC signaling. The MOI indicates an element, such as an "application" corresponding to each operator-specific access category.

[0305] At operation 4h-10, the UE NAS detected an access attempt.

[0306] During operation 4h-15, the UE NAS maps the access attempt to at least one access identifier and access class. There may not be any corresponding access identifier.

[0307] At operation 4h-20, the UE NAS sends a service request to the UE AS, including the mapped access identifier and access category information.

[0308] Figure 4I This is a flowchart illustrating the operation of a UE AS according to an embodiment of the present disclosure.

[0309] refer to Figure 4I At Operation 4i-05, the UE AS receives configuration prohibition information from the network via system information. Configuration prohibition information is provided for each access identifier and access category.

[0310] At Operation 4i-10, the UE AS receives a service request from the UE NAS, which includes access identifier and access category information.

[0311] At operation 4i-15, the UE AS determines whether to initially allow access based on prohibition configuration information corresponding to the access identifier. Two cases are considered. In one case, separate prohibition configuration information corresponding to the access identifier is provided, and the configuration information includes bitmap information as presented in the first or third embodiment. The UE AS determines whether at least one bit corresponding to the access category provided by the UE NAS is set to "0" in the bitmap of the prohibition configuration information corresponding to one or more mappings provided by the UE NAS; if so, access is assumed to always be allowed. For the prohibition configuration information of the first or second access identifier, even the bitmap information presented in the third embodiment is considered. The UE NAS simultaneously determines whether the bit corresponding to the access category is set to "0" and whether the UE belongs to the UE type indicated by the bitmap as presented in the third embodiment of this disclosure. When the UE belongs to the UE type indicated by the bitmap and when the bit corresponding to the access category is set to "0", the UE's access is allowed.

[0312] If access is not permitted using separate prohibition configuration information corresponding to the access identifier, the UE AS performs a prohibition check using configuration information corresponding to the access category to determine whether access is ultimately permitted.

[0313] In another scenario, the prohibition configuration information corresponding to the access category includes the bitmap information presented in the second or third embodiment. Before performing a prohibition check using the prohibition configuration information (i.e., ac-barringFactor and ac-barringtime) for the access category provided by the UE NAS, the UE AS determines whether at least one bit in the bitmap information presented in the second embodiment, corresponding to at least one access identifier provided by the UE NAS, is set to "0". If at least one bit is set to "0", access is allowed, thus omitting the prohibition check. For the case of the first or second identifier, the UE type presented in the third embodiment is further considered.

[0314] At operation 4i-20, the UE AS performs RRC connection establishment with the network and enters connection mode.

[0315] Figure 4J This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure.

[0316] refer to Figure 4J The UE includes a radio frequency (RF) processor 4j-10, a baseband processor 4j-20, a storage unit 4j-30, and a controller 4j-40.

[0317] RF processor 4j-10 has the function of transmitting / receiving signals through a radio channel, such as signal band conversion and amplification. For example, RF processor 4j-10 up-converts a baseband signal from baseband processor 4j-20 into an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back into a baseband signal. For example, RF processor 4j-10 may include transmit filters, receive filters, amplifiers, mixers, oscillators, DACs, and ADCs. Although one antenna is depicted in the figures, the UE may be equipped with multiple antennas. RF processor 4j-10 may also include multiple RF chains. RF processor 4j-10 can perform beamforming. For beamforming, RF processor 4j-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. RF processor 4j-10 can be configured to support MIMO schemes, using which the UE can receive signals from multiple layers simultaneously.

[0318] The baseband processor 4j-20 has baseband signal-to-bit string conversion capabilities according to the system's physical layer standard. For example, in data transmission mode, the baseband processor 4j-20 encodes and modulates the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 4j-20 demodulates and decodes the baseband signal from the RF processor 4j-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 4j-20 encodes and modulates the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs an inverse IFFT on the symbols, and inserts CP into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 4j-20 divides the baseband signal from the RF processor 1i-10 into OFDM symbols, performs an FFT on the OFDM symbols to recover the signal mapped to the subcarriers, and demodulates and decodes the signals to recover the transmitted bit string.

[0319] The baseband processor 4j-20 and RF processor 4j-10 process transmitted and received signals as described above. Therefore, the baseband processor 4j-20 and RF processor 4j-10 can be referred to as a transmitter, receiver, transceiver, or communication unit. At least one of the baseband processor 4j-20 and RF processor 4j-10 may include multiple communication modules for supporting different radio access technologies. At least one of the baseband processor 4j-20 and RF processor 4j-10 may also include multiple communication modules for processing signals in different frequency bands. For example, different radio access technologies may include wireless local area networks (WLANs) (e.g., IEEE 802.11) and cellular networks (e.g., LTE). Different frequency bands may include ultra-high frequency (SHF) bands (e.g., 2.5 GHz and 5 GHz bands) and mmWave bands (e.g., 60 GHz).

[0320] Storage unit 4j-30 stores data, such as basic procedures, application programs, and setting information for operating the UE. Storage unit 4j-30 can also store information about a second access node that uses a second radio access technology for wireless communication. Storage unit 4j-30 provides the stored information in response to requests from controller 4j-40.

[0321] Controller 4j-40 controls the overall operation of the UE. For example, controller 4j-40 controls baseband processor 4j-20 and RF processor 4j-10 to transmit and receive signals. Controller 4j-40 writes data to and reads data from storage unit 4j-30. For this purpose, controller 4j-40 may include at least one processor. For example, controller 4j-40 may include a CP for controlling communications and an AP for controlling higher-level programs (such as applications). Controller 4j-40 may include a multi-connection processor 4j-42 for handling operations in multi-connection mode.

[0322] According to embodiments of this disclosure, the UE may include some of the components depicted in the accompanying drawings, and the components of the UE are controlled by the controller 4j-40.

[0323] Figure 4K This is a block diagram illustrating the configuration of a gNB according to an embodiment of the present disclosure.

[0324] refer to Figure 4K The gNB includes an RF processor 4k-10, a baseband processor 4k-20, a backhaul communication unit 4k-30, a storage unit 4k-40, and a controller 4k-50.

[0325] The RF processor 4k-10 has the capability to transmit / receive signals via a radio channel, such as signal band conversion and amplification. For example, the RF processor 4k-10 up-converts a baseband signal from the baseband processor 4k-20 to an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back to a baseband signal. The RF processor 4k-10 may include, for example, transmit filters, receive filters, amplifiers, mixers, oscillators, DACs, and ADCs. Although one antenna is depicted in the figures, the gNB may be equipped with multiple antennas. The RF processor 4k-10 may also include multiple RF chains. The RF processor 4k-10 can perform beamforming. For beamforming, the RF processor 4k-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. The RF processor 4k-10 can be configured to transmit one or more layers of downlink MIMO operation.

[0326] The baseband processor 4k-20 has baseband signal-to-bit string conversion capabilities according to the system's physical layer standard. For example, in data transmission mode, the baseband processor 4k-20 performs encoding and modulation on the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 4k-20 performs demodulation and decoding on the baseband signal from the RF processor 4k-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 4k-20 performs encoding and modulation on the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs IFFT on the symbols, and inserts CP into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 4k-20 divides the baseband signal from the RF processor 4k-10 into OFDM symbols, performs FFT on the OFDM symbols to recover the signal mapped to the subcarriers, and performs demodulation and decoding on the signals to recover the transmitted bit string. The baseband processor 4k-20 and the RF processor 4k-10 process the transmitted and received signals as described above. Therefore, the baseband processor 4k-20 and the RF processor 4k-10 can be referred to as transmitters, receivers, transceivers, or communication units.

[0327] The backhaul communication unit 4k-30 provides an interface for communicating with other nodes in the network. For example, the backhaul communication unit 4k-30 converts bit strings to be sent from the gNB to another node (e.g., another gNB and the core network) into physical signals, and converts physical signals received from another node into bit strings.

[0328] Storage unit 4k-40 stores data such as basic procedures, applications, and settings information for gNB operation. Storage unit 4k-40 can also store information about bearers established for the UE and measurement results reported by connected UEs. Storage unit 4k-40 can also store information used by the UE when determining whether to enable or disable multiple connections. Storage unit 4k-40 can provide stored data based on requests from controller 4k-50.

[0329] The controller 4k-50 controls the overall operation of the gNB. For example, the controller 4k-50 controls the baseband processor 4k-20, the RF processor 4k-10, and the backhaul communication unit 4k-30 for transmitting and receiving signals. The controller 4k-50 reads and writes data to the storage unit 4k-40. For this purpose, the controller 4k-50 may include at least one processor. The controller 4k-50 may also include a multi-connectivity processor 4k-52 for handling operations in multi-connectivity mode.

[0330] According to embodiments of this disclosure, the gNB may also include some of the components depicted in the drawings, and the components of the gNB are controlled by the controller 4k-50.

[0331] Fifth embodiment

[0332] Embodiments of this disclosure are described with reference to the accompanying drawings. To avoid obscuring the subject matter of this disclosure, detailed descriptions of well-known functions and structures incorporated herein may be omitted. Furthermore, the following terms are defined based on the functions described in this disclosure and may vary depending on the intent, purpose, etc., of the user or operator. Therefore, the definitions should be made based on the overall content of this specification.

[0333] To avoid obscuring the subject matter of this disclosure, detailed descriptions of well-known functions and structures incorporated herein may be omitted. Embodiments of this disclosure are described with reference to the accompanying drawings.

[0334] In the following description, for ease of explanation, terminology is provided to indicate access nodes, network entities, messages, interfaces between network entities, and different identifying information. Therefore, the terminology used in the following description is not limited to its specific meaning, but may be replaced by other technically equivalent terms.

[0335] Figure 5A This is a diagram illustrating the architecture of an LTE system according to an embodiment of the present disclosure.

[0336] refer to Figure 5AThe radio access network of the LTE system includes evolved Node Bs (hereinafter, interchangeably referred to as eNB, Node B, and base station) 5a-05, 5a-10, 5a-15, and 5a-20; a Mobility Management Entity (MME) 5a-25; and a Serving Gateway (S-GW) 5a-30. User terminals (hereinafter, interchangeably referred to as user equipment (UE) and terminals) 5a-35 connect to the external network via eNBs 5a-05, 5a-10, 5a-15, and 5a-20 and S-GW 5a-30.

[0337] eNBs 5a-05, 5a-10, 5a-15, and 5a-20 correspond to traditional Node Bs in the Universal Mobile Telecommunications System (UMTS). UE 5a-35 connects to one of the eNBs via a radio channel, and the eNB has more complex functions than a traditional Node B. In LTE systems where all user services, including real-time services such as Voice over IP (VoIP), are served through a shared channel, entities are needed to collect UE-specific state information (such as buffer status, power margin status, and channel status) and schedule the UE based on the collected information; the eNB is responsible for these functions. Typically, one eNB carries multiple cells. For example, LTE systems use Orthogonal Frequency Division Multiplexing (OFDM) as the radio access technology to ensure data rates up to 100 Mbps within a 20 MHz bandwidth. LTE systems also employ Adaptive Modulation and Coding (AMC) to determine the modulation scheme and channel coding rate to suit the UE's channel conditions. The S-GW5a-30 handles data bearer functions to establish and release data bearers under the control of the MME 5a-25. The MME 5a-25 handles various control functions and mobility management functions for the UE and connects to eNBs 5a-05, 5a-10, 5a-15, and 5a-20.

[0338] Figure 5B This is a diagram illustrating the protocol stack of the interface between a UE and an eNB in ​​an LTE system according to an embodiment of the present disclosure.

[0339] refer to Figure 5BIn LTE systems, the protocol stack of the interface between the UE and eNB consists of multiple protocol layers stacked from bottom to top: the physical layer (denoted by reference numerals 5b-20 and 5b-25), the Media Access Control (MAC) layer (denoted by reference numerals 5b-15 and 5b-30), the Radio Link Control (RLC) layer (denoted by reference numerals 5b-10 and 5b-35), and the Packet Data Convergence Control (PDCP) layer (denoted by reference numerals 5b-05 and 5b-40). The PDCP layer (denoted by reference numerals 5b-05 and 5b-40) is responsible for compressing / decompressing IP headers. The main functions of the PDCP layer are summarized below:

[0340] -Header compression and decompression: ROHC only

[0341] -User data transmission

[0342] - The PDCP reconstruction process of RLC AM involves the sequential transfer of upper-layer PDUs.

[0343] - For split bearers in the DC (RLC AM only): PDCP PDU routing for transmission and PDCP PDU reordering for reception.

[0344] - The PDCP reconstruction process of RLC AM involves repeated detection of the lower-level SDU.

[0345] - Retransmit PDCP SDU during handover, and for separate bearers in the DC, retransmit PDCP PDU during the PDCP data recovery process of the RLC AM.

[0346] - Encryption and decryption

[0347] -Timer-based SDU dropping in the uplink

[0348] The RLC layer, designated by reference numerals 5b-10 and 5b-35, is responsible for reformatting the PDCP PDUs to fit the size of ARQ operations. The main functions of the RLC protocol are summarized below:

[0349] -Transmission of upper-layer PDUs

[0350] - Error correction via ARQ (AM data transmission only)

[0351] - Cascading, segmentation, and reassembly of RLC SDUs (UM and AM data transfer only)

[0352] - Resegmentation of RLC data PDUs (AM data transmission only)

[0353] - Reordering of RLC data PDUs (only for UM and AM data transfers)

[0354] - Duplicate detection (only for UM and AM data transfers)

[0355] - Protocol error detection (AM data transmission only)

[0356] -RLC SDU discard (only for UM and AM data transfers)

[0357] -RLC Reconstruction

[0358] The MAC layer, indicated by reference numerals 5b-15 and 5b-30 in the attached figures, allows the establishment of connections between multiple RLC entities for a UE and is responsible for multiplexing RLC PDUs from the RLC layer to MAC PDUs and demultiplexing MAC PDUs to RLC PDUs. The main functions of the MAC protocol are summarized below:

[0359] Mapping between logical channels and transport channels

[0360] - Multiplexing MAC SDUs belonging to one or different logical channels into a Transport Block (TB) transmitted to the physical layer on the transport channel / Demultiplexing MAC SDUs belonging to one or different logical channels from a Transport Block (TB) transmitted from the physical layer on the transport channel.

[0361] - Scheduling Information Report

[0362] - HARQ functionality (error correction via HARQ)

[0363] Priority processing between logical channels of a UE

[0364] - Prioritization among UEs is performed through dynamic scheduling.

[0365] -MBMS service identifier

[0366] -Transmission format selection

[0367] -filling

[0368] The PHY layer, indicated by reference numerals 5b-20 and 5b-25 in the attached figures, is responsible for channel coding and modulation of higher-layer data to generate OFDM symbols and transmit OFDM symbols on the radio channel. It also demodulates and decodes the OFDM symbols received on the radio channel to pass the decoded data to the higher layers.

[0369] Figure 5C This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure.

[0370] refer to Figure 5CThe next-generation mobile communication system's radio access network 5c-20 includes the new radio Node B (RNNB) 5c-10 and the new radio core network (NR CN) 5c-05. The new radio user equipment (hereinafter referred to as NR UE or simply UE) 5c-15 connects to external networks via NR NB 5c-10 and NR CN 5c-05.

[0371] exist Figure 5C In this context, NR NB 5c-10 corresponds to the evolved Node B (eNB) in a traditional LTE system. NR UE 5c-15 connects to an NR NB that can provide services superior to those of a traditional eNB. In next-generation mobile communication systems where all user traffic is served through a shared channel, entities are needed to collect UE-specific state information (such as buffer status, power margin status, and channel status) and schedule UEs based on the collected information; NR NB 5c-10 is responsible for these functions. Typically, one NR NB carries multiple cells. To meet the higher data rate requirements of traditional LTE, it is necessary to employ advanced technologies (such as Orthogonal Frequency Division Multiplexing (OFDM) as a radio access scheme and beamforming) to ensure a wider maximum bandwidth than before. Adaptive modulation and coding (AMC) techniques can be used to determine the modulation scheme and channel coding rate to suit the UE's channel conditions. NR CN 5c-05 is responsible for mobility management, bearer establishment, and QoS establishment. NR CN 5c-05 is also responsible for other control functions and UE mobility management functions associated with multiple NRNBs. The next-generation mobile communication system can interoperate with traditional LTE systems by connecting the NRCN 5c-05 to the Mobility Management Entity (MME) 5c-25 via a network interface. The MME 5c-25 is then connected to the eNB 5c-30, which acts as a traditional base station.

[0372] Figure 5D This is a diagram illustrating the protocol stack of the interface between an NR UE and an NR gNB in ​​a next-generation mobile communication system according to an embodiment of this disclosure.

[0373] refer to Figure 5D In next-generation mobile communication systems, the protocol stack for the interface between the NR UE and the NR gNB comprises multiple protocol layers stacked from bottom to top: the NR PHY layer (denoted by reference numerals 5d-20 and 5d-25), the NR MAC layer (denoted by reference numerals 5d-15 and 5d-30), the NR RLC layer (denoted by reference numerals 5d-10 and 5d-35), and the NR PDCP layer (denoted by reference numerals 5d-05 and 5d-40). The main functions of the NR PDCP layer (denoted by reference numerals 5d-05 and 5d-40) may include some of the following:

[0374] -Header compression and decompression: ROHC only

[0375] -User data transmission

[0376] - Sequential transmission of upper-layer PDUs

[0377] -Disordered transmission of upper-layer PDUs

[0378] - PDCP PDU reordering for received PDUs

[0379] -Duplicate detection of lower-level SDUs

[0380] -PDCP SDU retransmission

[0381] - Encryption and decryption

[0382] -Timer-based SDU dropping in the uplink

[0383] The PDCP PDU reordering function of the NRPDCP entity reorders PDCP PDUs transmitted from the lower layer based on the PDCP sequence number (PDCP SN). It can also include transmitting the reordered data to the upper layer, recording the lost PDCP PDUs in the reordered PDCP PDUs, sending a status report indicating the lost PDCP PDUs to the sender, and requesting the retransmission of the lost PDCP PDUs.

[0384] The main functions of the NRRLC layers, indicated by reference numerals 5d-10 and 5d-35 in the accompanying drawings, may include some of the following functions.

[0385] -Transmission of upper-layer PDUs

[0386] - Sequential transmission of upper-layer PDUs

[0387] -Disordered transmission of upper-layer PDUs

[0388] - Error correction via ARQ

[0389] Cascading, segmentation, and reassembly of RLC SDUs

[0390] - Resegmentation of RLC data PDUs

[0391] -RLC data PDU reordering

[0392] -Duplicate detection

[0393] -Protocol error detection

[0394] -RLC SDU discard

[0395] -RLC Reconstruction

[0396] The sequential delivery function of an NRRLC entity is to deliver RLC SDUs received from a lower layer to an upper layer, and may include: when receiving RLC SDUs that constitute multiple segments of the original RLC SDU, reassembling the RLC SDU and delivering the reassembled RLCSDU to the upper layer; reordering received RLC PDUs based on the RLC sequence number (SN) or PDCP SN; recording lost RLC PDUs in the reordered RLCPDUs; sending a status report to the sender indicating the lost RLC PDUs; requesting retransmission of lost RLC PDUs; and when there are lost RLC PDUs, sequentially delivering the RLC PDUs preceding the lost RLC PDU to the upper layer, and if even if there are any lost RLC SDUs but a predetermined timer expires, sequentially delivering all RLC PDUs received before the timer starts to the upper layer, or if even if there are any lost RLC SDUs but a predetermined timer expires, sequentially delivering all RLC PDUs received up to that time to the upper layer. RLC PDUs can also be processed in the order of receipt (arrival order regardless of sequence number) and delivered to the PDCP entity out of order (out-of-order delivery). If an RLC PDU is sent in segments, the received segments are stored, or the system waits until all segments constituting the RLC PDU are received and then reassembles the segments into the original RLC PDU, which is then delivered to the PDCP entity. The NR RLC layer may not have concatenation functionality, and in this case, concatenation can be performed in the NR MAC layer or replaced by multiplexing functionality in the NR MAC layer.

[0397] The out-of-order delivery function of the NRRLC entity is to deliver RLC SDUs received from the lower layer to the upper layer in an out-of-order manner, and may include: when receiving RLC SDUs consisting of multiple segments that make up the original RLC SDU, reassembling the segmented RLC SDUs, delivering the reassembled RLC SDUs to the upper layer, arranging the received RLC PDUs based on the RLC SN or PDCP SN, and recording the SN of any lost RLC PDUs.

[0398] In the NR MAC layer, as indicated by reference numerals 5d-15 and 5d-30, an NRMAC entity can be connected to multiple NRRLC entities, and the main functions of an NR MAC entity can include some of the following:

[0399] Mapping between logical channels and transport channels

[0400] -Multiplexing / Demultiplexing MAC SDU

[0401] - Scheduling Information Report

[0402] - Error correction via HARQ

[0403] Priority processing between logical channels of a UE

[0404] - Prioritization among UEs is performed through dynamic scheduling.

[0405] -MBMS service identifier

[0406] -Transmission format selection

[0407] -filling

[0408] The NRPHY layer, indicated by reference numerals 5d-20 and 5d-25 in the attached figures, is responsible for channel coding and modulation of upper-layer data to generate OFDM symbols and transmit OFDM symbols on the radio channel. It also demodulates and decodes the OFDM symbols received on the radio channel to pass the decoded data to the upper layer.

[0409] In next-generation mobile communication systems supporting high data rates, if a PDCP PDU is lost or delayed in a single-connectivity environment, if a PDCP PDU is discarded at the transmitter due to the expiration of a PDCP expiration timer, or if one of the two PDCP entities delays receiving a PDCP PDU in a dual-connectivity environment, all received data should be stored in a buffer until the reordering timer triggered at the receive PDCP layer expires, resulting in transmission delays. Therefore, the terminal must have a large-capacity memory or buffer to store all data received during the reordering timer's runtime. Insufficient memory or buffer capacity can lead to data loss. If data for which a PDCP reordering timer has been triggered arrives before the timer expires, or if the PDCP reordering timer expires, a large amount of data received during the timer's runtime may be transmitted to the upper layer all at once, potentially overwhelming the upper layer and causing data loss.

[0410] This disclosure proposes a novel PDCP status reporting method, characterized in that when a predetermined timer running at the receiving PDCP layer expires, when the amount of data stored in the receiving buffer becomes equal to or greater than a threshold, or when the reordering timer value reaches a predetermined time, the receiver triggers a PDCP status report and sends the PDCP status report to the transmitter. The transmitter receives and checks the PDCP status report to discard the data successfully received by the receiver (PDCP PDU or PDCPSDU) and quickly retransmits the lost data, thereby solving the transmission delay and data loss problems caused by the reordering timer running at the receiver.

[0411] This novel PDCP status reporting method enables the transmitter to discard successfully received data from the receiver and immediately retransmit the lost data based on the PDCP status report when a PDCP status report is received from the receiver.

[0412] Figure 5E This is a signal flow diagram illustrating the process by which the gNB configures the Packet Data Convergence Protocol (PDCP) Status Report Request function via RRC message when the UE establishes a connection with the network, according to an embodiment of this disclosure.

[0413] Figure 5E It describes the process by which a UE transitions from RRC idle mode or RRC inactive mode (or lightly-connected mode) to RRC connected mode to establish a connection with the network and configures whether to enable the PDCP status report request function.

[0414] refer to Figure 5EIf no data is sent to or received from the UE in RRC connection mode during the predetermined process or within the predetermined time period, the gNB can send an RRCConnectionRelease message to the UE at Operation 5E-01, causing the UE to enter idle mode. Afterwards, if any data needs to be sent, the UE in idle mode (hereinafter, interchangeably referred to as the idle mode UE) performs the RRC connection establishment procedure with the gNB. If the UE is in RRC inactive mode, it can send an RRCConnectionResumeRequest message to perform the RRC connection recovery procedure. At Operation 5e-05, the UE synchronizes its uplink with the gNB through a random access procedure and sends an RRCConnectionRequest message to the gNB. The RRCConnectionRequest message includes the UE identifier and the establishment cause. At Operation 5e-10, the gNB sends an RRCConnectionSetup message to the UE to establish a connection. This message may include information indicating whether a new PDCP status report is enabled by logical channel configuration, by bearer, or by PDCP entity configuration. More specifically, the IP flow or QoS flow that has enabled new PDCP status reporting can be indicated on each logical channel, each bearer, or each PDCP (or SDAP) entity. New PDCP status reporting can be enabled by configuring a buffer threshold or a threshold for a newly introduced timer or reordering timer as a condition for triggering new PDCP status reporting. This may be triggered if the amount of data in the buffer of a PDCP or RLC entity reaches a threshold, or if a newly introduced timer or reordering timer reaches a threshold. The RRCConnectionSetup message also includes RRC connection configuration information. The RRC connection, referred to as the Signaling Radio Bearer (SRB), is established to exchange RRC messages as control messages between the UE and the gNB. After establishing the RRC connection, at Operation 5e-15, the UE sends an RRCConnectionSetupComplete message to the gNB. If the gNB does not know and wants to know the capabilities of the UE connected to it, it can send a message to inquire about the UE's capabilities. This message may include an indicator indicating whether the UE has new PDCP status reporting capability or supports new PDCP status reporting.The RRCConnectionSetupComplete message includes a control message called SERVICEREQUEST, which the UE uses when requesting access from the MME and the Mobility Management Function (AMF), User Plane Function (UPF), or Session Management Function (SMF) for bearer establishment for a specific service. At Operation 5E-20, the gNB sends the SERVICE REQUEST message to the MME / AMF / UPF / SMF, and the MME / AMF / UPF / SMF determines whether to provide the UE's service request. If it is determined that the service requested by the UE should be provided, at Operation 5e-25, the MME / AMF / UPF / SMF sends the INITIAL CONTEXT SETUP REQUEST message to the gNB. This message includes Quality of Service (QoS) information for configuring the Data Radio Bearer (DRB) and security information (e.g., security keys and security algorithms) to be applied to the DRB. At operation 5e-30, the gNB sends a SecurityModeCommand message to the UE and at operation 5e-35 receives a SecurityModeComplete message from the UE for security configuration. After security configuration is complete, at operation 5e-40, the gNB sends an RRCConnectionReconfiguration message to the UE. This message includes information indicating whether new PDCP status reporting is enabled by logical channel configuration, by bearer, or by PDCP entity configuration. More specifically, it can indicate the IP flow or QoS flow on each logical channel, each bearer, or each PDCP (or SDAP) entity where new PDCP status reporting is enabled. New PDCP status reporting can be enabled by configuring a buffer threshold or a threshold for a newly introduced timer or reordering timer as a condition for triggering new PDCP status reporting. In this case, new PDCP status reporting may be triggered if the amount of data in the buffer of the PDCP or RLC entity reaches the threshold, or if a newly introduced timer or reordering timer reaches the threshold.The RRCConnectionReconfiguration message also includes information for configuring the DRB for user data transmission. The UE configures the DRB based on this DRB configuration information and sends an RRCConnectionReconfigurationComplete message to the gNB at operation 5e-45. After establishing the DRB with the UE, at operation 5e-50, the gNB sends an INI CONTEXT RESPONSE message to the MME. At operation 5e-55, when the MME receives the INI CONTEXT RESPONSE message for establishing an S1 bearer with the S-GW, it sends an S1 BEARERSETUP message to the S-GW. At operation 5e-60, it receives an S1 BEARER SETUP RESPONSE message from the S-GW. The S1 bearer is a connection established between the S-GW and the gNB for data transmission and corresponds one-to-one with the DRB. Once the above process is successfully completed, at operations 5e-65 and 5e-70, the UE sends and receives data via the gNB and the S-GW. The data transmission process can be divided into three phases: RRC connection configuration, security configuration, and DRB configuration. At Operation 5e-75, the gNB can also send an RRCConnectionReconfiguration message to the UE to update, supplement, or modify the configuration. This message includes information indicating whether new PDCP status reporting is enabled by logical channel configuration, by bearer, or by PDCP entity configuration. More specifically, it can indicate the IP flow or QoS flow on each logical channel, each bearer, or each PDCP (or SDAP) entity where new PDCP status reporting is enabled. New PDCP status reporting can be enabled by configuring a buffer threshold or a threshold for a newly introduced timer or reordering timer as a triggering condition. In this case, a new PDCP status report may be triggered if the amount of data in the buffer used for the PDCP or RLC entity reaches the threshold, or if a newly introduced timer or reordering timer reaches the threshold.

[0415] Figure 5F This is a diagram illustrating the transmission delay and data loss problem caused by the PDCP reordering timer of the PDCP entity according to an embodiment of the present disclosure.

[0416] refer to Figure 5FThe transmitting PDCP entity can send data (PDCP PDU or PDCP SDU) with a 12-bit PDCP sequence number (0, 1, 2, 3, ..., 2^(12-1)). Due to HARQ retransmissions by the MAC entity or ARQ retransmissions by the RLC entity depending on the radio link conditions, the receiving PDCP entity can receive data out of order rather than in ascending order of PDCP sequence numbers. In the event of the transmitting PDCP entity's PDCP discard timer expiring or data loss occurring on the radio link, the PDCP entity may fail to receive data (PDCP PDU or PDCP SDU) with a specific PDCP sequence number or receive the data too late.

[0417] exist Figure 5F In the case where data with PDCP sequence number 2 (PDCP PDU or PDCP SDU) has not arrived, data with PDCP sequence number 3 (PDCP PDU or PDCP SDU) can arrive at the receiving PDCP entity indicated by reference numeral 5f-05. In this situation, the receiving PDCP entity triggers a PDCP reordering timer to receive data with PDCP sequence numbers (PDCP PDU or PDCP SDU) for sequentially transmitting the data to the upper layer, as shown in reference numeral 5f-10. The PDCP reordering timer indicates the time the PDCP entity waits for the lost data to arrive. If the PDCP reordering timer expires, the receiving PDCP entity determines that data with PDCP sequence numbers lower than those for which the PDCP reordering timer has been triggered that has not yet arrived is lost, and transmits the data with PDCP sequence numbers lower than those for which the PDCP reordering timer has been triggered to the upper layer in ascending order of PDCP sequence numbers.

[0418] However, for services requiring high data rates, if the PDCP reordering timer is set to the same long period as before, it is necessary to buffer large amounts of received data because data cannot be passed to the upper layer until the PDCP reordering timer expires or lost data arrives, as shown in Figure 5f-15. Increasing the size of the buffer or memory is expensive and thus increases the overall manufacturing cost of the UE. In a state where a large amount of data is stored in the buffer due to the arrival delay of some data, if the reordering timer expires or lost data arrives, all the data stored in the buffer is passed to the upper layer at once. In this case, the upper layer may not be able to process the large amount of data correctly and may discard data at a predetermined level or rate, resulting in data loss.

[0419] To solve the reference Figure 5FIn response to the problems described, this disclosure proposes a new PDCP status report, a method for triggering a new PDCP status report, and operations for sending and receiving PDCP entities.

[0420] Figure 5G This is a diagram illustrating the format of a first type of PDCP status report according to an embodiment of this disclosure.

[0421] refer to Figure 5G According to embodiments of this disclosure, for the case using a 12-bit PDCP sequence number, the first type of PDCP status report can be configured in format 2g-05; for the case using an 18-bit PDCP sequence number, it can be configured in format 2g-10; and for the case using a 32-bit PDCP count value, it can be configured in format 2g-15. In formats 5g-05, 5g-10, and 5g-15, the D / C field indicates whether the buffered data is PDCP user data (PDCP data PDU) or PDCP control data (PDCP control PDU), while the PDU type field indicates the type of PDCP control PDU. The First Missing Sequence number (FMS) field indicates the sequence number of the first lost PDU, and the First Missing Count value (FMC) field indicates the PDCP count value of the first lost PDU within the receive reordering window. The bitmap field following the FMC or FMS field consists of multiple bits mapped in ascending order to PDCP PDUs with consecutive PDCP sequence numbers or PDCP count values. Each bit is set to 0 or 1 to indicate whether the corresponding PDCP data was successfully received.

[0422] To indicate the use of the first type of PDCP status report presented in this disclosure, the PDU type field is set to 011, as shown in Table 4. One of the other reserved values ​​(e.g., 100 to 111) may also be used.

[0423] [Table 4]

[0424]

[0425]

[0426] To solve the problem caused by the reference Figure 5F The problem caused by the transmission delay of the described PDCP reordering timer can be triggered by the receiver under the following circumstances: For example, if the UE anticipates the occurrence of the above-described problem, it triggers a first-type PDCP status report by sending a first-type PDCP status report to the transmitter to request the rapid retransmission of lost data (PDCP PDU or PDCP SDU).

[0427] The receiver may trigger a Type I PDCP status report when at least one of the following conditions is met.

[0428] 1. The amount of data stored in the receive buffer or memory is equal to or greater than a predetermined amount.

[0429] 2. The amount of data stored in the receive buffer or memory is equal to or greater than the threshold configured via the RRC message.

[0430] 3. The new timer configured via RRC message expires.

[0431] 4. The PDCP reordering timer has reached the value configured via the RRC message.

[0432] 5. According to the implementation method, a first type of PDCP status report request is required.

[0433] 6. Upon receiving an RRC message indicating a request for a Type 1 PDCP status report,

[0434] 7. Received data with a PDCP header including a 1-bit polling indicator.

[0435] 8. The PDCP control PDU that instructs the request for a first-type PDCP status report, and

[0436] 9. The MAC entity receives a MAC CE indicating a request for a first status report.

[0437] RRC messages can be in Figure 5E One of the RRC messages sent in operations 5e-10, 5e-40, and 5e-75.

[0438] In embodiments of this disclosure, the transmitter may send an RRC message or request for a first type of PDCP status report to the receiver via MACCE, PDCP header or PDCP control PDU when one of the following conditions is met.

[0439] 1. Whenever a newly defined timer expires, the transmitter may periodically request a Type 1 PDCP status report from the receiver via an indicator included in an RRC message, MAC CE, or PDCP control PDU.

[0440] 2. Whenever a newly defined timer expires, the transmitter may periodically request a Type 1 PDCP status report from the receiver via a 1-bit indicator (e.g., the PDCP polling bit) defined in the PDCP header.

[0441] 3. Depending on the implementation of the transmitter, the transmitter may request a first type of PDCP status report from the receiver via an RRC message, a MAC CE, or an indication in a PDCP control PDU.

[0442] 4. The transmitter may request a first type of PDCP status report from the receiver by means of a 1-bit indicator (e.g., PDCP polling bit) configured in the PDCP header, depending on the implementation of the transmitter or as determined.

[0443] The newly defined timer can be a timer for a first-type PDCP status report, such as t-StatusReportType3.

[0444] In this disclosure, when a first type of PDCP status report is triggered, the receiver or receiving PDCP entity operates as follows.

[0445] If a Type 1 PDCP status report is triggered at the receiver according to the aforementioned Type 1 PDCP status report triggering conditions, the receiver can distinguish between successfully received data and lost data associated with a PDCP sequence number or PDCP count value (a PDCP sequence number or PDCP count value belonging to the PDCP receive window), where the PDCP sequence number or PDCP count value is less than the RX-REORD variable in the PDCP receive window variables that indicates the PDCP reordering status report was triggered; configuration Figure 5G The data format described in the document includes the D / C field, PDU type field, FMC or FMS field, and bitmap field, to generate a first-type PDCP status report; and the first-type PDCP status report is sent to the receiver.

[0446] Optionally, if a first-type PDCP status report is triggered at the receiver according to the first-type PDCP status report triggering conditions described above, the receiver can distinguish between successfully received data and lost data associated with a PDCP sequence number or PDCP count value (a PDCP sequence number or PDCP count value belonging to the PDCP receive window), where the PDCP sequence number or PDCP count value is less than the RX-REORD variable in the PDCP receive window variables that indicates the predicted next PDCP sequence number or PDCP COUNT value to be received; configuration Figure 5G The data format described in the document includes the D / C field, PDU type field, FMC or FMS field, and bitmap field, to generate a first-type PDCP status report; and the first-type PDCP status report is sent to the receiver.

[0447] Optionally, if a first-type PDCP status report is triggered at the receiver according to the aforementioned first-type PDCP status report triggering conditions, the receiver can distinguish between successfully received data and lost data associated with a PDCP sequence number or PDCP count value (a PDCP sequence number or PDCP count value belonging to the PDCP receive window), where the PDCP sequence number or PDCP count value is less than the RX-REORD variable in the PDCP receive window variables, which indicates the first PDCP sequence number or PDCP COUNT value that has not yet been transmitted to the upper layer; configuration Figure 5G The data format described in the document includes the D / C field, PDU type field, FMC or FMS field, and bitmap field, to generate a first-type PDCP status report; and the first-type PDCP status report is sent to the receiver.

[0448] In this disclosure, when a first type of PDCP status report is received, the transmitter or the PDCP sending entity operates as follows.

[0449] If a Type 1 PDCP status report is received, the transmitting PDCP entity can check successfully transmitted data (PDCP PDU or PDCP SDU) and lost data, discard successfully transmitted data from the transmit buffer, and retransmit lost data stored in the buffer. For example, the transmitting PDCP entity can retrieve lost data from the transmit buffer and send the retrieved data to the lower layer for retransmission. To enable the lower layer to prioritize sending the retransmission target data of the PDCP entity, the PDCP entity can send a fast pass or accelerated pass indicator to the lower layer. If this indicator is received, the lower layer (RLC entity) will assume that the data from the upper layer is the retransmission target data (PDCP PDU) and prioritize sending the corresponding data.

[0450] Optionally, if a Type 1 PDCP status report is received, the transmitting PDCP entity can check successfully transmitted data (PDCP PDU or PDCP SDU) and lost data, discard successfully transmitted data from the transmit buffer, and retrieve lost data that has already been sent to the lower layer for retransmission. For example, the transmitting PDCP entity can retrieve lost data from the transmit buffer and send the retrieved data to the lower layer for retransmission. To enable the lower layer to prioritize sending the retransmission target data of the PDCP entity, the PDCP entity can send a fast delivery or accelerated delivery indicator to the lower layer. If this indicator is received, the lower layer (RLC entity) will assume that the data from the upper layer is the retransmission target data (PDCP PDU) and prioritize sending the corresponding data.

[0451] According to embodiments of this disclosure, in addition to the first type of PDCP status report, a second type of PDCP status report can also be defined and used. As described above, the first type of PDCP status report is characterized in that, if the transmitter receives the first type of PDCP status report, it discards the successfully transmitted data and quickly retransmits the lost data. However, in the case of the second type of PDCP status report, although the transmitter discards the successfully transmitted data immediately after receiving the second type of PDCP status report, it only retransmits the lost data when performing the PDCP reconstruction process or the PDCP data recovery process, rather than immediately after receiving the second type of PDCP status report.

[0452] Both the first and second type PDCP status reports can be used Figure 5G The format described herein differs only in the PDU type field values. The triggering conditions for the first type of PDCP status report described above can be applied to the second type of PDCP status report in the same manner. The first and second types of PDCP status reports can be configured in the same way. Therefore, it is clear that in this disclosure, the second type of PDCP status report can be used in place of the first type of PDCP status report.

[0453] Figure 5H A flowchart illustrating the operations of a sending PDCP entity and a receiving PDCP entity for processing a proposed PDCP status report according to an embodiment of this disclosure is described.

[0454] refer to Figure 5H If one of the above triggering conditions is met at operation 5h-05 to trigger a PDCP status report, the receiving PDCP entity configures the PDCP status report at operation 5h-10, and at operation 5h-15, for reference... Figure 5G The format described is used to send PDCP status reports. If the sending PDCP entity receives a PDCP status report during operation 5h-20, it can discard successfully transmitted data and perform retransmission of the lost data during operation 5h-25. The sending PDCP entity can also send an indicator to the lower layer indicating that the retransmission target data should be sent first.

[0455] According to another embodiment of this disclosure, for use in Figure 5EIn the case where one of the RRC messages sent at operations 5e-10, 5e-40, and 5e-75 is a PDCP entity or bearer configuration new PDCP status report request function, if the transmitter requests a new PDCP status report from the receiver via a 1-bit polling indicator in the PDCP header, a PDCP control PDU, a MAC CE, or an RRC message, or if the receiver's PDCP status report triggering conditions described above are met, the receiver triggers the first type of PDCP status report as presented in this disclosure, and the transmitter checks the first type of PDCP status report to discard successfully transmitted data and immediately perform retransmission of the lost data. However, for PDCP entities or bearers not using the... Figure 5E In the case where one of the RRC messages sent at operations 5e-10, 5e-40, and 5e-75 configures the new PDCP status report request function, if the transmitter requests a new PDCP status report from the receiver via a 1-bit polling indicator in the PDCP header, a PDCP control PDU, a MAC CE, or an RRC message, or if the receiver meets the aforementioned PDCP status report triggering conditions, the receiver triggers the second type of PDCP status report as disclosed in this disclosure, and the transmitter checks the second type of PDCP status report to discard successfully transmitted data, and performs retransmission of lost data only when performing the PDCP reconstruction process or the PDCP data recovery process, rather than immediately performing retransmission of lost data upon receiving the second type of PDCP status report.

[0456] Figure 5I This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure.

[0457] refer to Figure 5I The UE includes a radio frequency (RF) processor 5i-10, a baseband processor 5i-20, a storage unit 5i-30, and a controller 5i-40.

[0458] The RF processor 5i-10 has the function of transmitting / receiving signals through a radio channel, such as signal band conversion and amplification. For example, the RF processor 5i-10 up-converts the baseband signal from the baseband processor 5i-20 into an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back into a baseband signal. For example, the RF processor 5i-10 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, and an ADC. Although one antenna is depicted in the figures, the UE may be equipped with multiple antennas. The RF processor 5i-10 may also include multiple RF chains. The RF processor 5i-10 can perform beamforming. For beamforming, the RF processor 5i-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. The RF processor 5i-10 can be configured to support MIMO schemes, using which the UE can receive multiple layers simultaneously. The RF processor 5i-10, under the control of the controller 5I-40, can appropriately configure multiple antennas or antenna elements to perform beam scanning and adjust beam direction and beamwidth, thereby achieving alignment of the receive and transmit beams.

[0459] The baseband processor 5i-20 features baseband signal-to-bit string conversion functionality according to the system physical layer standard. For example, in data transmission mode, the baseband processor 5i-20 encodes and modulates the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 5i-20 demodulates and decodes the baseband signal from the RF processor 5i-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 5i-20 encodes and modulates the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs an IFFT on the symbols, and inserts a cyclic prefix (CP) into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 5i-20 divides the baseband signal from the RF processor 5i-10 into OFDM symbols, performs an FFT on the OFDM symbols to recover the signal mapped to the subcarriers, and demodulates and decodes the signals to recover the transmitted bit string.

[0460] The baseband processor 5i-20 and RF processor 5i-10 process transmitted and received signals as described above. Therefore, the baseband processor 5i-20 and RF processor 5i-10 can be referred to as a transmitter, receiver, transceiver, or communication unit. At least one of the baseband processor 5i-20 and RF processor 5i-10 may include multiple communication modules for supporting different radio access technologies. At least one of the baseband processor 5i-20 and RF processor 5i-10 may also include multiple communication modules for processing signals in different frequency bands. For example, different radio access technologies may include wireless local area networks (WLANs) (e.g., IEEE 802.11) and cellular networks (e.g., LTE). Different frequency bands may include ultra-high frequency (SHF) bands (e.g., 2.5 GHz and 5 GHz bands) and mmWave bands (e.g., 60 GHz).

[0461] Storage unit 5i-30 stores data, such as basic programs, applications, and settings information for UE operation. Storage unit 5i-30 provides the stored information in response to requests from controller 5i-40.

[0462] Controller 5i-40 controls the overall operation of the UE. For example, controller 5i-40 controls baseband processor 5i-20 and RF processor 5i-10 to transmit and receive signals. Controller 5i-40 writes data to and reads data from storage unit 5i-30. For this purpose, controller 5i-40 may include at least one processor. For example, controller 5i-40 may include a CP for controlling communications and an AP for controlling higher-level programs (such as applications). Controller 5i-40 may include a multi-connection processor 5i-42 for handling operations in multi-connection mode.

[0463] According to embodiments of this disclosure, the UE may include some of the components depicted in the accompanying drawings, and the components of the UE are controlled by the controller 5i-40.

[0464] Figure 5J This is a block diagram illustrating the configuration of a gNB according to an embodiment of the present disclosure.

[0465] refer to Figure 5J The gNB includes an RF processor 5j-10, a baseband processor 5j-20, a backhaul communication unit 5j-30, a storage unit 5j-40, and a controller 5j-50.

[0466] The RF processor 5j-10 has the function of transmitting / receiving signals through a radio channel, such as frequency band conversion and amplification of signals. For example, the RF processor 5j-10 up-converts a baseband signal from the baseband processor 5j-20 into an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back into a baseband signal. For example, the RF processor 5j-10 may include transmit filters, receive filters, amplifiers, mixers, oscillators, DACs, and ADCs. Although one antenna is depicted in the figures, the gNB may be equipped with multiple antennas. The RF processor 5j-10 may also include multiple RF chains. The RF processor 5j-10 can perform beamforming. For beamforming, the RF processor 5j-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. The RF processor 5j-10 can be configured to transmit one or more layers of downlink MIMO operation.

[0467] The baseband processor 5j-20 has baseband signal-to-bit string conversion capabilities according to the system's physical layer standard. For example, in data transmission mode, the baseband processor 5j-20 encodes and modulates the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 5j-20 demodulates and decodes the baseband signal from the RF processor 5j-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 5j-20 encodes and modulates the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs an IFFT on the symbols, and inserts CP into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 5j-20 divides the baseband signal from the RF processor 5j-10 into OFDM symbols, performs a Fast Fourier Transform (FFT) on the OFDM symbols to recover the signal mapped to the subcarriers, and demodulates and decodes the signal to recover the transmitted bit string. The baseband processor 5j-20 and the RF processor 5j-10 process the transmitted and received signals as described above. Therefore, the baseband processor 5j-20 and the RF processor 5j-10 can be referred to as transmitters, receivers, transceivers, or communication units.

[0468] The 5j-30 backhaul communication unit provides an interface for communicating with other nodes in the network.

[0469] Storage unit 5j-40 stores data such as basic procedures, application programs, and setting information for gNB operation. Storage unit 5j-40 can also store information about bearers established for the UE and measurement results reported by connected UEs. Storage unit 5j-40 can also store information used by the UE when determining whether to enable or disable multiple connections. Storage unit 5j-40 can provide stored data based on requests from controller 5j-50.

[0470] Controller 5j-50 controls the overall operation of the gNB. For example, controller 5j-50 controls baseband processor 5j-20, RF processor 5j-10, and backhaul communication unit 5j-30 for transmitting and receiving signals. Controller 5j-50 writes data to and reads data from storage unit 5j-40. For this purpose, controller 5j-50 may include at least one processor. Controller 5j-50 may also include a multi-connection processor 5j-52 for handling operations in multi-connection mode.

[0471] According to embodiments of this disclosure, the gNB may also include some of the components depicted in the drawings, and the components of the gNB are controlled by controller 5j-50.

[0472] Sixth Embodiment

[0473] Embodiments of this disclosure are described with reference to the accompanying drawings. To avoid obscuring the subject matter of this disclosure, detailed descriptions of well-known functions and structures incorporated herein may be omitted. Furthermore, the following terminology is defined based on the functions described in this disclosure and may vary depending on the intent, purpose, etc., of the user or operator. Therefore, the definitions should be made based on the overall content of this specification. In the following description, for ease of explanation, terms are provided to indicate access nodes, network entities, messages, interfaces between network entities, and different identifying information. Therefore, the terms used in the following description are not limited to their specific meanings but may be replaced by other technically equivalent terms.

[0474] Figure 6A This is a diagram illustrating the architecture of an LTE system according to an embodiment of the present disclosure.

[0475] refer to Figure 6A The radio access network of the LTE system includes evolved Node Bs (hereinafter, interchangeably referred to as eNB, Node B, and base station) 6a-05, 6a-10, 6a-15, and 6a-20; a Mobility Management Entity (MME) 6a-25; and a Service Gateway (S-GW) 6a-30. User terminals (hereinafter, interchangeably referred to as user equipment (UE) and terminals) 6a-35 connect to the external network via eNBs 6a-05, 6a-10, 6a-15, and 6a-20 and S-GW 6a-30.

[0476] eNBs 6a-05, 6a-10, 6a-15, and 6a-20 correspond to traditional Node Bs in the Universal Mobile Telecommunications System (UMTS). The UE 6a-35 connects to one of the eNBs via a radio channel, and the eNB has more complex functions than a traditional Node B. In LTE systems where all user services, including real-time services such as Voice over IP (VoIP), are served through a shared channel, entities are needed to collect UE-specific state information (such as buffer status, power margin status, and channel status) and schedule the UE based on the collected information; the eNB is responsible for these functions. Typically, one eNB carries multiple cells. For example, LTE systems use Orthogonal Frequency Division Multiplexing (OFDM) as the radio access technology to ensure data rates up to 100 Mbps within a 20 MHz bandwidth. LTE systems also employ Adaptive Modulation and Coding (AMC) to determine the modulation scheme and channel coding rate to suit the UE's channel conditions. The S-GW 6a-30 handles data bearer functions to establish and release data bearers under the control of the MME 6a-25. The MME 6a-25 handles various control functions and mobility management functions for the UE and connects to eNBs 6a-05, 6a-10, 6a-15 and 6a-20.

[0477] Figure 6B This is a diagram illustrating the protocol stack of the interface between a UE and an eNB in ​​an LTE system according to an embodiment of the present disclosure.

[0478] refer to Figure 6B In LTE systems, the protocol stack of the interface between the UE and eNB consists of multiple protocol layers stacked from bottom to top: the physical layer (denoted by reference numerals 6b-20 and 6b-25), the Media Access Control (MAC) layer (denoted by reference numerals 6b-15 and 6b-30), the Radio Link Control (RLC) layer (denoted by reference numerals 6b-10 and 6b-35), and the Packet Data Convergence Control (PDCP) layer (denoted by reference numerals 6b-05 and 6b-40). The PDCP layer (denoted by reference numerals 6b-05 and 6b-40) is responsible for compressing / decompressing IP headers. The main functions of the PDCP layer are summarized below:

[0479] -Header compression and decompression: ROHC only

[0480] -User data transmission

[0481] - The PDCP reconstruction process of RLC AM involves the sequential transfer of upper-layer PDUs.

[0482] - For split bearers in the DC (RLC AM only): PDCP PDU routing for transmission and PDCP PDU reordering for reception.

[0483] - The PDCP reconstruction process of RLC AM involves repeated detection of the lower-level SDU.

[0484] - Retransmit PDCP SDU during handover, and for separate bearers in the DC, retransmit PDCP PDU during the PDCP data recovery process of the RLC AM.

[0485] - Encryption and decryption

[0486] -Timer-based SDU dropping in the uplink

[0487] The RLC layer, designated by reference numerals 6b-10 and 6b-35, is responsible for reformatting the PDCP PDUs to fit them to the size of ARQ operations. The main functions of the RLC protocol are summarized below:

[0488] -Transmission of upper-layer PDUs

[0489] - Error correction via ARQ (AM data transmission only)

[0490] - Cascading, segmentation, and reassembly of RLC SDUs (UM and AM data transfer only)

[0491] - Resegmentation of RLC data PDUs (AM data transmission only)

[0492] - Reordering of RLC data PDUs (only for UM and AM data transfers)

[0493] - Duplicate detection (only for UM and AM data transfers)

[0494] - Protocol error detection (AM data transmission only)

[0495] -RLC SDU discard (only for UM and AM data transfers)

[0496] -RLC Reconstruction

[0497] The MAC layer, indicated by reference numerals 6b-15 and 6b-30 in the attached figures, allows the establishment of connections between multiple RLC entities for a UE and is responsible for multiplexing RLC PDUs from the RLC layer to MAC PDUs and demultiplexing MAC PDUs to RLC PDUs. The main functions of the MAC protocol are summarized below:

[0498] Mapping between logical channels and transport channels

[0499] - Multiplexing MAC SDUs belonging to one or different logical channels into a transport block (TB) passed to the physical layer on the transport channel / Demultiplexing MAC SDUs belonging to one or different logical channels from a transport block (TB) passed from the physical layer on the transport channel.

[0500] - Scheduling Information Report

[0501] - Error correction via HARQ

[0502] Priority processing between logical channels of a UE

[0503] - Prioritization among UEs is performed through dynamic scheduling.

[0504] -MBMS service identifier

[0505] -Transmission format selection

[0506] -filling

[0507] The PHY layer, indicated by reference numerals 6b-20 and 6b-25 in the attached figures, is responsible for channel coding and modulation of higher-layer data to generate OFDM symbols and transmit OFDM symbols on the radio channel. It also demodulates and decodes the OFDM symbols received on the radio channel to pass the decoded data to the higher layers.

[0508] Figure 6C This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure.

[0509] refer to Figure 6C The next-generation mobile communication system's radio access network 6c-20 includes the new radio Node B (RNNB) 6c-10 and the new radio core network (NR CN) 6c-05. The new radio user equipment (hereinafter referred to as NR UE or simply UE) 6c-15 connects to external networks via NR NB 6c-10 and NR CN 6c-05.

[0510] exist Figure 6CIn this context, NR NB 6c-10 corresponds to the evolved Node B (eNB) in a traditional LTE system. NRUE 6c-15 connects to an NR NB that can provide services superior to those of a traditional eNB. In next-generation mobile communication systems where all user traffic is served through a shared channel, entities are needed to collect UE-specific state information (such as buffer status, power margin status, and channel status) and schedule UEs based on the collected information; NR NB 6c-10 is responsible for these functions. Typically, one NR NB carries multiple cells. To meet the higher data rate requirements of traditional LTE, it is necessary to employ advanced technologies (such as Orthogonal Frequency Division Multiplexing (OFDM) as a radio access scheme and beamforming) to ensure a wider maximum bandwidth than before. Adaptive modulation and coding (AMC) techniques can be used to determine the modulation scheme and channel coding rate to suit the UE's channel conditions. NR CN 6c-05 is responsible for mobility management, bearer establishment, and QoS establishment. NR CN 6c-05 is also responsible for other control functions and UE mobility management functions associated with multiple NRNBs. The next-generation mobile communication system can interoperate with traditional LTE systems by connecting the NRCN 6c-05 to the Mobility Management Entity (MME) 6c-25 via a network interface. The MME 6c-25 is then connected to the eNB 6c-30, which acts as a traditional base station.

[0511] Figure 6D This is a diagram illustrating the protocol stack of the interface between an NR UE and an NR gNB in ​​a next-generation mobile communication system according to an embodiment of this disclosure.

[0512] refer to Figure 6D In next-generation mobile communication systems, the protocol stack for the interface between the NR UE and the NR gNB comprises multiple protocol layers stacked from bottom to top: the NR PHY layer (denoted by reference numerals 6d-20 and 6d-25), the NR MAC layer (denoted by reference numerals 6d-15 and 6d-30), the NR RLC layer (denoted by reference numerals 6d-10 and 6d-35), and the NR PDCP layer (denoted by reference numerals 6d-05 and 6d-40). The main functions of the NR PDCP layer (denoted by reference numerals 6d-05 and 6d-40) may include some of the following:

[0513] -Header compression and decompression: ROHC only

[0514] -User data transmission

[0515] - Sequential transmission of upper-layer PDUs

[0516] - PDCP PDU reordering for received PDUs

[0517] -Duplicate detection of lower-level SDUs

[0518] -PDCP SDU retransmission

[0519] - Encryption and decryption

[0520] -Timer-based SDU dropping in the uplink

[0521] The PDCP PDU reordering function of the NRPDCP entity reorders the PDCP PDUs passed from the lower layer based on the PDCP sequence number (PDCP SN). It can also include passing the reordered data to the upper layer, recording the lost PDCP PDUs in the reordered PDCP PDUs, sending a status report indicating the lost PDCP PDUs to the sender, and requesting the retransmission of the lost PDCP PDUs.

[0522] The main functions of the NRRLC layers, indicated by reference numerals 6d-10 and 6d-35 in the accompanying drawings, may include some of the following functions.

[0523] -Transmission of upper-layer PDUs

[0524] - Sequential transmission of upper-layer PDUs

[0525] -Disordered transmission of upper-layer PDUs

[0526] - Error correction via ARQ

[0527] Cascading, segmentation, and reassembly of RLC SDUs

[0528] - Resegmentation of RLC data PDUs

[0529] -RLC data PDU reordering

[0530] -Duplicate detection

[0531] -Protocol error detection

[0532] -RLC SDU discard

[0533] -RLC Reconstruction

[0534] The sequential delivery function of an NRRLC entity is to deliver RLC SDUs received from a lower layer to an upper layer, and may include: when receiving RLC SDUs that constitute multiple segments of the original RLC SDU, reassembling the RLC SDU and delivering the reassembled RLCSDU to the upper layer; reordering received RLC PDUs based on the RLC sequence number (SN) or PDCP SN; recording lost RLC PDUs in the reordered RLCPDUs; sending a status report to the sender indicating the lost RLC PDUs; requesting retransmission of lost RLC PDUs; and when there are lost RLC PDUs, sequentially delivering the RLC PDUs preceding the lost RLC PDU to the upper layer, and if even if there are any lost RLC SDUs but a predetermined timer expires, sequentially delivering all RLC PDUs received before the timer starts to the upper layer, or if even if there are any lost RLC SDUs but a predetermined timer expires, sequentially delivering all RLC PDUs received up to that time to the upper layer. RLC PDUs can also be processed in the order of receipt (arrival order regardless of sequence number) and delivered to the PDCP entity out of order (out-of-order delivery). If an RLC PDU is sent in segments, the received segments are stored, or the system waits until all segments constituting the RLC PDU are received and then reassembles the segments into the original RLC PDU, which is then delivered to the PDCP entity. The NR RLC layer may not have concatenation functionality, and in this case, concatenation can be performed in the NR MAC layer or replaced by multiplexing functionality in the NR MAC layer.

[0535] The out-of-order delivery function of the NRRLC entity is to deliver RLC SDUs received from the lower layer to the upper layer in an out-of-order manner, and may include: when receiving RLC SDUs consisting of multiple segments that make up the original RLC SDU, reassembling the segmented RLC SDUs, delivering the reassembled RLC SDUs to the upper layer, arranging the received RLC PDUs based on the RLC SN or PDCP SN, and recording the SN of any lost RLC PDUs.

[0536] In the NR MAC layer, as indicated by reference numerals 6d-15 and 6d-30, an NRMAC entity can be connected to multiple NRRLC entities, and the main functions of an NR MAC entity can include some of the following:

[0537] Mapping between logical channels and transport channels

[0538] -Multiplexing / Demultiplexing MAC SDU

[0539] - Scheduling Information Report

[0540] - Error correction via HARQ

[0541] Priority processing between logical channels of a UE

[0542] - Prioritization among UEs is performed through dynamic scheduling.

[0543] -MBMS service identifier

[0544] -Transmission format selection

[0545] -filling

[0546] The NRPHY layer, indicated by reference numerals 6d-20 and 6d-25 in the attached figures, is responsible for channel coding and modulation of upper-layer data to generate OFDM symbols and transmit OFDM symbols on the radio channel. It also demodulates and decodes the OFDM symbols received on the radio channel to pass the decoded data to the upper layer.

[0547] Figure 6E This is a diagram illustrating discontinuous reception (DRX) operation of a UE in idle mode in an LTE system according to an embodiment of the present disclosure.

[0548] refer to Figure 6E Each of the UEs 6e-10 and 6e-15 in idle mode monitors the PDCCH to receive paging messages from the eNB 6e-05. DRX, adopted in LTE as an effective UE power-saving technique, is characterized by configuring the DRX cycle such that the receiver remains in sleep mode during the "off" period and wakes up at predetermined intervals during the "on" period. For example, the paging cycle is configured so that the UE receives messages from network 6e-05, as shown in reference numerals 6e-25 and 6e-30. If a UE (one of UEs 6e-10 and 6e-15) detects a paging RNTI (P-RNTI), it processes the corresponding downlink paging message. The paging message includes the UE ID, causing other UEs with different UE IDs to discard the received information and enter sleep mode according to the DRX cycle. Since the UE is unaware of the DRX cycle, HARQ is not applied during the DRX cycle.

[0549] Network 6e-05 configures subframe 6e-20 for paging UEs. This configuration is based on the smaller of the UE-requested period Tue and the cell-specific period Tc. The paging period is set to one of 32, 64, 128, and 256 frames. A paging subframe 6e-20 within a frame can be identified based on the UE's International Mobile Subscriber Identity (IMSI). Since UEs have different IMSIs, each UE operates according to the paging instance belonging to that UE among all paging opportunities 63-35.

[0550] Paging messages can be sent in a predetermined number of subframes 6e-20, which can be configured as shown in Table 5.

[0551] [Table 5]

[0552]

[0553] Figure 6F This is a diagram illustrating the DRX operation of a UE in Radio Resource Control (RRC) connection mode in an LTE system according to an embodiment of the present disclosure.

[0554] refer to Figure 6FDRX is also supported in RRC connected mode, and the operation in RRC connected mode differs from that in RRC idle mode. DRX in connected mode is called Connected Mode DRX (CDRX). As mentioned above, if the UE continuously monitors the PDCCH for scheduling information, this will result in significant power consumption. The CDRX is configured with a DRX period 6f-00, which has an on-duration segment 6f-05 during which the UE is woken up to perform PDCCH monitoring. The CDRX can be configured with two DRX periods: a long DRX period and a short DRX period. The long DRX period is typically configured, and the eNB can trigger a short DRX period using a MAC CE if needed. After a predetermined time period, the UE switches from the short DRX period to the long DRX period. Initial scheduling information for the specific UE is provided in the predetermined PDCCH. Therefore, the UE only monitors the corresponding PDCCH candidate to minimize power consumption. If scheduling information for a new packet is received during the on-duration segment 6f-05, as shown in reference numeral 6f-10, the UE starts a DRX inactivity timer, as shown in reference numeral 6f-15. When the DRX inactivity timer is running, the UE remains active. For example, the UE continuously monitors the PDCCH. Additionally, the HARQ RTT timer is active, as shown in reference numeral 6f-20. The HARQ RTT timer prevents the UE from unnecessarily performing PDCCH monitoring during the HARQ Round Trip Time (RTT); that is, the UE does not need to perform PDCCH monitoring while the timer is running. However, when both the DRX inactivity timer and the HARQ RTT timer are running, the UE continuously monitors the PDCCH according to the DRX inactivity timer. If the HARQ RTT timer expires, the DRX retransmission timer is active, as shown in reference numeral 6f-25. When the DRX retransmission timer is running, the UE must continuously monitor the PDCCH. Typically, when the DRX retransmission timer is running, scheduling information for HARQ retransmission is received, as shown in reference numeral 6f-30. If the UE receives the scheduling information, it immediately stops the DRX retransmission timer and restarts the HARQ RTT timer. This operation is repeated until a packet is successfully received, as shown in reference numeral 6f-35.

[0555] The UE receives CDRX operation-related configuration information via the RRCConnectionReconfiguration message. Each of the on-duration timer, DRX inactivity timer, and DRX retransmission timer specifies the number of PDCCH subframes. The timer expires when the specified number of PDCCH subframes has elapsed. In FDD, all downlink subframes can transmit PDCCH; in TDD, downlink subframes and special subframes can transmit PDCCH. In TDD, downlink, uplink, and special subframes exist in the same frequency band. Downlink subframes and special subframes are considered as PDCCH subframes.

[0556] The eNB can be configured with two states: longDRX and shortDRX. Typically, based on power preference indication information sent by the UE, UE mobility history information, and the characteristics of the configured DRB, the eNB can remain in one of these two states. The transition between these two states is triggered by the expiration of a predetermined timer or the reception of a predetermined MAC CE.

[0557] Figure 6G This is a diagram illustrating packet delay budget reporting operations for improving the quality of LTE voice (VoLTE) in a wireless communication system according to an embodiment of this disclosure.

[0558] In LTE, the recommended end-to-end (E2E) one-way latency time to meet current VoLTE QoS requirements is 150ms, with an allowable value of 40ms.

[0559] refer to Figure 6G When two UEs, 6g-05 and 6g-10, use VoLTE service via their respective eNBs, 6g-15 and 6g-20, the VoLTE service quality can vary depending on the channel quality established with the eNB. UE 1 (3g-15) might have good VoLTE quality, while UE 2 (3g-20) might have poor VoLTE quality. The eNB can adjust the UE's CDRX period based on the aforementioned one-way packet delay time, and especially for MTC UEs, can adjust the UE's retransmission period. Typically, when channel conditions between the eNB and UE are good, the eNB configures CDRX for the corresponding UE to reduce unnecessary power consumption. However, if channel conditions between the eNB and UE are poor, the eNB does not configure CDRX for the corresponding UE. Figure 6G The embodiments are for CDRX reconfiguration request operations when UE 1 6g-05 and UE 2 6g-10 are experiencing poor VoLTE service quality (see Table 6).

[0560] [Table 6]

[0561]

[0562]

[0563] As summarized in Table 6, if the channel conditions between UE 1 6g-05 and eNB 2 6g-15 are good, and the channel conditions between UE 2 6g-10 and eNB 2 6g-20 are poor, and the VoLTE quality at both UE 1 6g-05 and UE 2 6g-10 is poor, it is likely that CDRX will be configured for UE 1 6g-05 instead of UE 2 6g-10. However, CDRX operations associated with UE 1 6g-05 may lead to a further reduction in VoLTE communication performance with UE 2 6g-10, affecting packet reception failures at UE 2 6g-20 during its CDRX sleep period. If UE 1 6g-05 knows the E2E one-way delay time with eNB 2 6g-20, it can calculate its allowable delay value and requested CDRX cycle value based on the corresponding delay time and the CDRX cycle configured for the serving eNB. For example, the allowable E2E delay can be calculated using the following equation.

[0564] Allowable E2E delay = E2E delay margin (400ms) - Measured E2E delay

[0565] For example, assuming the E2E latency requirement (latency margin) is 400ms and the UE measures an E2E latency of 200ms, the UE allows an additional 200ms of latency. If UE 1 6g-05 is currently configured with a CDRX period of 160ms, it can adjust the configured CDRX period value to improve VoLTE performance or increase the CDRX period to save power. The measured E2E latency can be considered as the sum of the configured CDRX period value and the packet transmission latency on the radio and wired channels, and the maximum change in CDRX period can be 100ms (allowed E2E latency value / 2). This is the case when considering the channels of both UE 1 6g-05 and UE 2 6g-10 by taking into account the operation of other UEs; the value can be changed precisely. For example, if the CDRX period value decreases, the UE can receive packets more frequently, thereby improving VoLTE performance. The CDRX period change value that the UE can request can be configured based on the allowed E2E latency value, depending on the UE's implementation. Since the eNB and network know the exact value of the E2E transmission delay measured by the UE, the corresponding operation can be triggered by the UE. For example, for delay budget reporting, the UE can request a CDRX period value of Y ms as the target value for change, based on the E2E transmission delay value measured by the UE instead of the previously configured CDRX period value. Once the request message is received, the eNB reconfigures the previously configured CDRX period.

[0566] Figure 6H This is a diagram illustrating a method for measuring packet transmission delay in a VoLTE system according to an embodiment of the present disclosure.

[0567] refer to Figure 6H For reference Figure 6G In short, because the eNB and network cannot measure the one-way packet delay time between UEs, the one-way packet delay time between UEs cannot be known unless the UE reports an accurate packet delay measurement. During VoLTE service, the UE can send data using Real Time Protocol (RTP) packets and measure E2E delay time by sending and receiving Real Time Control Protocol (RTCP) packets. Figure 6H Part (A) describes the sender report format for RTCP packets; the Last Sender Report (LSR) and Delay since LSR (DLSR) in the sender report format can be used to measure E2E packet delay time. For example, Figure 6H The one-way E2E delay time described in part (B) can be calculated using the following equation.

[0568] One-way E2E delay = ((time A – time LSR) - DLSR) / 2

[0569] This method is just an example, and the packet transmission delay between UEs can be calculated using various methods. The reason for dividing the numerator by 2 is that the transmitter can measure the E2E delay based on the round-trip time, i.e., E2E is half the round-trip time.

[0570] Figure 6I This is a signal flow diagram illustrating a method for a UE to request a change in the CDRX cycle and to transmit and receive data in the changed CDRX cycle, according to an embodiment of this disclosure.

[0571] refer to Figure 6I ,refer to Figure 6I The described process applies to both LTE and next-generation mobile communication systems.

[0572] UE 1 and UE 2, in RRC connection mode, are connected to gNB 1 and gNB 2 respectively to send and receive voice data via VoLTE service. This embodiment pertains to a VoLTE service-related process in which the UE measures the E2E latency and requests a change in the CDRX period to reconfigure the DRX period, thereby improving VoLTE service quality. However, this disclosure is not limited to VoLTE service (i.e., voice data service), but can be applied in the same manner to other types of services.

[0573] At Operation 6i-05, UE 1 connected to eNB 1 and UE 2 connected to eNB 2 are making a voice call via VoLTE service. VoLTE data communication can be performed using RTP packets, and in this case, at Operation 6i-10, the UE can send and receive RTCP packets, and decode the corresponding field values ​​in the RTCP packets (as shown in the reference). Figure 6H The round-trip time of packets is measured using the method described above. At operations 6i-15 and 6i-20, UE 1 and UE 2 can measure the one-way transmission delay time based on the signal transmitted at operation 6i-10 for E2E delay measurement. For example, the one-way E2E delay time can be obtained by dividing the packet round-trip time measured at operation 6i-10 by 2. Although this embodiment includes all operations of UE 1 and UE 2, each UE operates independently. For example, the same operation can be performed by one or both of UE 1 and UE 2. Furthermore, the same operation can be performed by UE 1 and UE 2 at different timings.

[0574] At operations 6i-25 and 6i-30, UE 1 and UE 2 can request to change the CDRX cycle or repetition transmission cycle of the eMTC UE based on the measured one-way transmission delay time and the predetermined required E2E delay requirement time margin value, in order to improve VoLTE quality. In this embodiment of the present disclosure, the DRX cycle change is performed in such a manner that the UE sends a DRX cycle change request to the corresponding gNB via a delay budget request. At operations 6i-35 and 6i-40, the delay budget request can be transmitted in an RRC message (i.e., UEAssistanceInformation). This UEAssistanceInformation is generated in the format shown in Table 7. Here, the DRX cycle change request corresponds to the Type 1 field value of the DelayBudgetReport-14 IE, and the UE sets the Type 1 field to the target DRX cycle value to be changed.

[0575] [Table 7]

[0576]

[0577]

[0578] UEAssistanceInformation message

[0579] In this operation, there are several options for selecting the DRX period as a reference.

[0580] Option 1: Long DRX cycle of MCG (Master Cell Group)

[0581] - Apply the long DRX period value set for MCG

[0582] Option 2: Short DRX cycle of MCG

[0583] - Apply the short DRX cycle value set for MCG

[0584] 3. Option 3: The actual DRX cycle of MCG (the long or short DRX cycle of the current application)

[0585] - Apply the DRX period value (long DRX or short DRX) currently set for MCG.

[0586] 4. Option 4: If a short DRX period is configured for the MCG, then the short DRX period of the MCG. Otherwise, the long DRX period of the MCG.

[0587] - If a short DRX period is set for MCG, then the short DRX period value of MCG will be applied.

[0588] 5. Option 5: The DelayBudgetReport indicates which DRX period should be adjusted.

[0589] -DelayBudgetReport indicates the DRX value to apply.

[0590] At operations 6i-45 and 6i-50, eNB 1 and eNB 2 reconfigure the DRX cycle based on the DRX cycle change request signal received from the UE (UE 1 and UE 2). The eNB can reconfigure the DRX cycle as requested via a DRX cycle change request included in an RRC report message from the UE, or according to its own determination or eNB implementation. At operations 6i-55 and 6i-60, the eNB sends an RRC message to the UE including the reconfigured DRX cycle value. Thereafter, UE 1 and UE 2 continue to perform services (VoLTE or another data communication) according to the reconfigured DRX cycle, and perform an E2E latency measurement operation at operation 6i-65. If, at operation 6i-65, the currently requested DRX change value calculated based on the one-way packet latency measured by the UE is different from the previously requested DRX cycle, the DRX change request operation from operations 6i-25 to 6i-60 is triggered.

[0591] Figure 6J This is a flowchart illustrating the CDRX cycle change process of a UE according to an embodiment of the present disclosure.

[0592] refer to Figure 6JAt Operation 6j-05, the UE in connected mode measures the one-way E2E delay. One-way E2E delay can be measured in various ways, such as by sending / receiving RTP packets, particularly RTCP packets. When using RTCP packets, the UE decodes the specific fields configured for E2E delay measurement in the RTCP packets, measures the round-trip time of the packets sent by the transmitter, and measures the one-way D2D delay based on the measurement result. At Operation 6j-10, the UE determines to change the CDRX period based on the measured one-way E2E delay and a predetermined E2E delay requirement (which can be predetermined based on time margin and QoS). For example, if the currently configured DRX period is too long or too short to match the E2E delay requirement, data transmission / reception performance can be improved by adjusting the DRX period. For example, if a UE using VoLTE service has poor VoLTE quality and the measured E2E value exceeds the E2E delay requirement, the UE can request a reduction in the CDRX period value to improve VoLTE quality and meet the E2E delay requirement. For reference, the CDRX period value and E2E latency are related; therefore, if the DRX period decreases, the E2E latency also decreases. This is because the E2E latency should be longer than the CDRX period, since no data is transmitted / received during the CDRX period. Otherwise, if the UE's VoLTE quality is good and if the measured E2E latency value is less than the E2E latency requirement, the UE can request an increase in the CDRX period value to achieve power saving gains for the UE.

[0593] At operation 6j-15, the UE triggers a delay budget report and generates a delay budget report message, which includes the changed DRX cycle value expected by the UE as determined in previous operations. Here, the DRX cycle change request can correspond to the Type 1 field value of the DelayBudgetReport-14 IE in the UEAssistanceInformation message as RRC signaling, where the Type 1 field is configured with the DRX cycle value requested by the UE to be changed. The corresponding information can be sent via other RRC messages or MAC CE.

[0594] At operation 6j-20, the UE receives an RRC message (RRCConnectionReconfiguration) from the gNB and reconfigures the DRX period. At operation 6j-25, the UE compares the currently reconfigured preferred DRX period value with the previously reported DRX period value to perform a first operation if the two values ​​are the same, and a second operation if the two values ​​are different. In the first operation of operation 6j-30, the UE maintains the current configuration and sends / receives data; in the second operation of operation 6j-35, the UE triggers a delay budget report to re-request the UE's desired DRX period value via RRC signaling. This means repeating operations 6j-10 to 6j-20.

[0595] Figure 6K This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure.

[0596] refer to Figure 6K The UE includes a radio frequency (RF) processor 6k-10, a baseband processor 6k-20, a storage unit 6k-30, and a controller 6k-40.

[0597] The RF processor 6k-10 has the function of transmitting / receiving signals through a radio channel, such as signal band conversion and amplification. For example, the RF processor 6k-10 up-converts the baseband signal from the baseband processor 6k-20 into an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back into a baseband signal. For example, the RF processor 6k-10 may include transmit filters, receive filters, amplifiers, mixers, oscillators, DACs, and ADCs. Although one antenna is depicted in the figures, the UE may be equipped with multiple antennas. The RF processor 6k-10 may also include multiple RF chains. The RF processor 6k-10 can perform beamforming. For beamforming, the RF processor 6k-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. The RF processor 6k-10 can be configured to support MIMO schemes, using which the UE can receive multiple layers simultaneously.

[0598] The baseband processor 6k-20 features baseband signal-to-bit string conversion functionality according to the system physical layer standard. For example, in data transmission mode, the baseband processor 6k-20 encodes and modulates the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 6k-20 demodulates and decodes the baseband signal from the RF processor 6k-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 6k-20 encodes and modulates the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs an IFFT on the symbols, and inserts CP into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 6k-20 divides the baseband signal from the RF processor 6k-10 into OFDM symbols, performs an FFT on the OFDM symbols to recover the signal mapped to the subcarriers, and demodulates and decodes the signals to recover the transmitted bit string.

[0599] The baseband processor 6k-20 and RF processor 6k-10 process transmitted and received signals as described above. Therefore, the baseband processor 6k-20 and RF processor 6k-10 can be referred to as a transmitter, receiver, transceiver, or communication unit. At least one of the baseband processor 6k-20 and RF processor 6k-10 may include multiple communication modules for supporting different radio access technologies. At least one of the baseband processor 6k-20 and RF processor 6k-10 may also include multiple communication modules for processing signals in different frequency bands. For example, different radio access technologies may include wireless local area networks (WLANs) (e.g., IEEE 802.11) and cellular networks (e.g., LTE). Different frequency bands may include ultra-high frequency (SHF) bands (e.g., 2.5 GHz and 5 GHz bands) and mmWave bands (e.g., 60 GHz).

[0600] Storage unit 6k-30 stores data such as basic procedures, applications, and settings information for operating the UE. Storage unit 6k-30 can also store information about a second access node that uses a second radio access technology for radio communication. Storage unit 6k-30 provides the stored information in response to requests from controller 6k-40.

[0601] Controller 6k-40 controls the overall operation of the UE. For example, controller 6k-40 controls baseband processor 6k-20 and RF processor 6k-10 to transmit and receive signals. Controller 6k-40 writes data to and reads data from storage unit 6k-30. For this purpose, controller 6k-40 may include at least one processor. For example, controller 6k-40 may include a CP for controlling communications and an AP for controlling higher-level programs (such as applications). Controller 6k-40 may include a multi-connection processor 6k-42 for handling operations in multi-connection mode.

[0602] According to embodiments of this disclosure, the UE may include some of the components depicted in the accompanying drawings, and the components of the UE are controlled by the controller 5i-40.

[0603] Figure 6L This is a block diagram illustrating the configuration of a gNB according to an embodiment of the present disclosure.

[0604] refer to Figure 6L The gNB includes an RF processor 6l-10, a baseband processor 6l-20, a backhaul communication unit 6l-30, a storage unit 6l-40, and a controller 6l-50.

[0605] RF processor 6l-10 has the function of transmitting / receiving signals through a radio channel, such as frequency band conversion and amplification of signals. For example, RF processor 6l-10 up-converts a baseband signal from baseband processor 6l-20 to an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back to a baseband signal. For example, RF processor 6l-10 may include transmit filters, receive filters, amplifiers, mixers, oscillators, DACs, and ADCs. Although one antenna is depicted in the figures, the gNB may be equipped with multiple antennas. RF processor 6l-10 may also include multiple RF chains. RF processor 6l-10 can perform beamforming. For beamforming, RF processor 6l-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. RF processor 6l-10 can be configured to transmit one or more layers of downlink MIMO operation.

[0606] The baseband processor 61-20 has baseband signal-to-bit string conversion functionality according to the system physical layer standard. For example, in data transmission mode, the baseband processor 61-20 encodes and modulates the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 61-20 demodulates and decodes the baseband signal from the RF processor 61-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 61-20 encodes and modulates the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs an IFFT on the symbols, and inserts CP into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 61-20 divides the baseband signal from the RF processor 61-10 into OFDM symbols, performs a Fast Fourier Transform (FFT) on the OFDM symbols to recover the signal mapped to the subcarriers, and demodulates and decodes the signal to recover the transmitted bit string. The baseband processor 61-20 and the RF processor 61-10 process the transmitted and received signals as described above. Therefore, the baseband processor 6l-20 and the RF processor 6l-10 can be referred to as transmitters, receivers, transceivers, or communication units.

[0607] The backhaul communication unit 6l-30 provides an interface for communicating with other nodes in the network. For example, the backhaul communication unit 6l-30 converts bit strings to be sent from the gNB to another node (e.g., another gNB and the core network) into physical signals, and converts physical signals received from another node into bit strings.

[0608] Storage unit 6l-40 stores data such as basic procedures, application programs, and setting information for gNB operation. Storage unit 6l-40 can also store information about bearers established for the UE and measurement results reported by connected UEs. Storage unit 6l-40 can also store information used by the UE when determining whether to enable or disable multiple connections. Storage unit 6l-40 can provide stored data based on requests from controller 6l-50.

[0609] Controller 6l-50 controls the overall operation of the gNB. For example, controller 6l-50 controls baseband processor 6l-20, RF processor 6l-10, and backhaul communication unit 6l-30 for transmitting and receiving signals. Controller 6l-50 reads and writes data to storage unit 6l-40. For this purpose, controller 6l-50 may include at least one processor. Controller 6l-50 may also include a multi-connection processor 6l-52 for handling operations in multi-connection mode.

[0610] The sixth embodiment of this disclosure can be summarized as follows.

[0611] Question 1: Which DRX cycle?

[0612] delayBudgetAdjustment

[0613] This parameter indicates the preferred increment / decrement relative to the current configuration. This parameter has a millisecond value. For example, ms40 corresponds to 40 milliseconds, msMinus40 corresponds to -40 milliseconds, and so on.

[0614] As mentioned above, the UE reports the preferred DRX cycle relative to the current DRX cycle. The question is, which DRX cycle is the current DRX cycle? Is it the MCG DRX cycle or the SCG DRX cycle, or the short DRX cycle or the long DRX cycle?

[0615] Possible options

[0616] Option 1: Long DRX cycle of MCG

[0617] Option 2: Short DRX cycle of MCG

[0618] Option 3: The actual DRX cycle of MCG (the long or short DRX cycle of the current application)

[0619] Option 4: If a short DRX cycle is configured for the MCG, then the short DRX cycle of the MCG.

[0620] Otherwise, the long DRX cycle of MCG

[0621] Option 5: The DelayBudgetReport indicates which DRX period should be adjusted.

[0622] (Option 1: MCG's long DRX cycle)

[0623] Option 2: Short DRX cycle of MCG

[0624] Option 3: The actual DRX cycle of MCG (the long or short DRX cycle of the current application)

[0625] Option 4: If a short DRX cycle is configured for the MCG, then the short DRX cycle of the MCG.

[0626] Otherwise, the long DRX cycle of MCG

[0627] Option 5: The DelayBudgetReport indicates which DRX period should be adjusted.

[0628] Question 2: Unnecessary reports caused by changes in the current DRX cycle

[0629] This embodiment addresses the scenario where the UE retransmits the delay budget report if the current delayBudgetAdjustment differs from the reported one. However, delayBudgetAdjustment may change due to a change in the reference value (the current DRX period) rather than a change in UE preference.

[0630] The above comparison should be made between the current preference and the reported preference.

[0631] (Question 2: Unnecessary reporting due to changes in the current DRX cycle)

[0632] In the current specification, if the current delayBudgetAdjustment differs from the reported one, the UE retransmission delay budget is reported.

[0633] However, delayBudgetAdjustment may change, not because of a change in user preferences, but because of a change in the reference value (i.e., the current DRX cycle).

[0634] The comparison should be made between the current preference and the reported preference. (The text can be updated as follows)

[0635] According to embodiments of this disclosure, the gNB may also include some of the components depicted in the drawings, and the components of the gNB are controlled by controller 5j-50.

[0636] Seventh Embodiment

[0637] Figure 7A This is a diagram illustrating the architecture of a next-generation mobile communication system according to an embodiment of the present disclosure.

[0638] refer to Figure 7A The next-generation mobile communication system's radio access network includes the new radio Node B (gNB) 7a-10 and the new radio core network (AMF) 7a-05. The new radio user equipment (hereinafter referred to as NRUE or simply UE) 7a-15 connects to external networks via gNB 7a-10 and AMF 7a-05.

[0639] exist Figure 7AIn this context, gNB 7a-10 corresponds to the evolved Node B (eNB) in a traditional LTE system. NR UE 7a-15 connects to a gNB that can provide services superior to those of a traditional eNB. In next-generation mobile communication systems where all user traffic is served through a shared channel, entities are needed to collect UE-specific state information (such as buffer status, power margin status, and channel status) and schedule UEs based on the collected information; gNB 7a-10 is responsible for these functions. Typically, a gNB carries multiple cells. To meet the higher data rate requirements of traditional LTE, it is necessary to employ advanced technologies (such as Orthogonal Frequency Division Multiplexing (OFDM) as a radio access scheme and beamforming) to ensure a wider maximum bandwidth than before. Adaptive modulation and coding (AMC) techniques can be used to determine the modulation scheme and channel coding rate to suit the UE's channel conditions. AMF 7a-05 is responsible for mobility management, bearer establishment, and QoS establishment. AMF 7a-05 is also responsible for other control functions and UE mobility management functions associated with multiple gNBs. The next-generation mobile communication system can interoperate with legacy LTE systems by connecting the AMF 7a-05 to the Mobility Management Entity (MME) 7a-25 via a network interface. The MME 7a-25 connects to the eNB 7a-30, which acts as a legacy base station. UEs supporting LTE-NR dual connectivity can establish connections to the eNB 7a-30, as shown in the attached reference numeral 7a-35, and to the gNB 7a-10, as shown in the attached reference numeral 7a-20.

[0640] Figure 7B This is a diagram illustrating a method for determining whether to accept access in a conventional LTE system according to an embodiment of the present disclosure.

[0641] refer to Figure 7BThe functions of an LTE UE are divided into Access Layer (AS) 7b-15 and Non-Access Layer (NAS) 7b-20. The AS is responsible for all access-related functions, while the NAS 7b-05 is responsible for non-access-related functions such as Public Land Mobile Network (PLMN) selection and service requests. Accessibility determination can be primarily made by the UE AS. As mentioned above, a congested network can restrict new access, and for this purpose, it broadcasts relevant configuration information so that each UE can make its own access determination, as shown in reference numeral 7b-35. With the introduction of new requirements in legacy LTE systems, new prohibition mechanisms have been proposed, resulting in allowing multiple access prohibition checks. If the UE NAS layer issues a service request, as shown in reference numeral 7b-10, the UE AS checks whether the UE can actually access the network. If the establishment reason value of the service request is "delay-tolerant access," the UE AS first performs an Extended Access Prohibition (EAB), as shown in reference numeral 7b-20. The EAB prohibition mechanism is performed as an access check procedure applicable only to Machine Type Communication (MTC). If the EAB check passes, the UE AS performs dedicated congestion control (ACDC) 7b-55 for data communication, as shown in reference numeral 7b-20. The application requesting service is assigned an ACDC category, the value of which can be included in the service request transmitted to the UE AS. The network can provide prohibition configuration information for each ACDC category. Therefore, the access check procedure can be performed on a per-group basis, categorized by ACDC category. If the prohibition configuration information for each ACDC category is not provided by the network, the UE AS omits the ACDC access check procedure. If the ACDC check passes, the UE AS performs access level prohibition (ACB), as shown in reference numeral 7b-30. ACB is an access check procedure using prohibition configuration information provided separately based on Mobile Initiated (MO) data or MO signaling. For Multi-Telephone (MMTEL) voice / video / SMS services, the ACB procedure can be omitted using an ACB skip indicator, as shown in reference numeral 7b-25. If all the above access checks pass, the UE AS can attempt to access the network. For example, the UE AS performs random access and sends a Radio Resource Control (RRC) Connection Request message to the eNB, as shown in reference numerals 7b-40. There may be another access check procedure not performed by the UE AS. If a Voice / Video Cancellation Configuration Message (SSAC) is received from the network, as shown in reference numerals 7b-45, the UE AS forwards this message to the IMS layer responsible for managing services within the UE, as shown in reference numerals 7b-50. After receiving the cancellation configuration message, the IMS layer can perform the access check procedure when a service is triggered. SSAC was introduced with the UE AS designed to perform the corresponding function, regardless of the application or service type.Therefore, in order to control the determination of whether to accept access to a specific service (such as MMTEL voice / video), it is necessary to transmit the prohibition configuration information directly to the layer that manages the service so that the corresponding layer can perform the access check process.

[0642] In next-generation mobile communication systems, such a complex process is unnecessary. This is because it is possible to design a single access check procedure that incorporates all the requirements introduced in LTE from the outset. This disclosure proposes a single prohibition mechanism evolved from the traditional ACDC access check procedure.

[0643] Figure 7C This is a diagram illustrating the process of performing ACDC operation in an LTE system according to an embodiment of the present disclosure.

[0644] refer to Figure 7C In LTE systems, ACDC (Advanced Access Control) has been proposed to determine accessibility for each application (service). Each application is assigned at least one ACDC category value. The ACDC category value is selected from a range of 1 to 16. At Operation 7c-25, Network 7c-20 provides the ACDC category information for each application to UE NAS 7c-10 using NAS messages. At Operation 7c-50, Network 7c-20 provides UE AS 7c-15 with prohibition configuration information to be applied to each ACDC category using System Information Block 2 (SIB2). The prohibition configuration information includes the ac-BarringFactor Information Element (IE) and the ac-Barringtime IE. The value of ac-BarringFactor α is in the range of 0 ≤ α < 1. UE AS 7c-15 extracts a random value of rand within the range of 0 ≤ rand < 1; if the random value is less than ac-BarringFactor, access is assumed to be not prohibited; otherwise, access is assumed to be prohibited. If access is determined to be denied, the UE AS 7c-15 will delay the access attempt for a duration based on the following equation.

[0645] Equation

[0646] “Tbarring (0.7 + 0.6 * rand) * ac - BarringTime”. If a service request is triggered, at operation 7c-30, UE AS 7c-15 extracts the ACDC category value corresponding to the application for that service. At operation 7c-35, UE AS 7c-10 sends a service request including the ACDC category value to UE AS 7c-15. Upon receiving the service request, at operation 7c-40, UE AS 7c-15 determines whether access is accepted based on the ACDC prohibition configuration information included in SIB2 according to the ACDC category value. If SIB2 does not include prohibition configuration information corresponding to the ACDC category, it is assumed that the application belonging to that ACDC category is allowed access during the ACDC process. If access is allowed through the access prohibition check process, at operation 7c-45, UE AS 7c-15 sends an RRC connection request for random access to the network.

[0647] Figure 7D This is a diagram illustrating the structure of ACDC configuration information used in a conventional LTE system according to an embodiment of the present disclosure.

[0648] refer to Figure 7D The ACDC configuration information (ACDC-BarringForCommon-r13) 7d-10 can provide PLMN-specific prohibition configuration information sets (ACDC-BarringPerPLMN 1, ACDC-BarringPerPLMN 2, ...) 7d-35 and 7d-40. If all PLMNs have the same prohibition configuration information set, a single prohibition configuration information set (ACDC-BarringForCommon-r13) 7d-05 can be set most broadly. PLMN-specific or common prohibition configuration information sets include category-specific prohibition configuration information 7d-20, 7d-25, and 7d-30. As mentioned above, prohibition configuration information 7d-45 includes ac-BarringFactor IE and ac-Barringtime IE. If there is no prohibition configuration information for a specific ACDC category, it is assumed that applications belonging to the corresponding ACDC category are not prohibited by ACDC.

[0649] Figure 7E This is a diagram illustrating a process for controlling access of a UE in connected or inactive mode according to an embodiment of the present disclosure.

[0650] refer to Figure 7EThis disclosure proposes a method for controlling access based on access identifiers and access categories, similar to conventional ACDC. Access identifiers are indication information defined in 3GPP standards, i.e., explicitly specified in standard documents. Access identifiers are used to indicate one of several access types, as shown in Table 8. They primarily indicate access types classified as Access Class 11 to 15 and those with high priority, such as Multimedia Priority Service (MPS) and Dedicated Service (Mission-Critical Service (MCS)). Access Class 11 to 15 indicate operator-dedicated or public-purpose access.

[0651] [Table 8]

[0652]

[0653]

[0654] Access categories are divided into two categories. One of these categories is the standardized access category. This category is defined at the RAN level, i.e., explicitly classified in standard documents. Therefore, the same standardized access category applies to different operators. In this disclosure, the emergency-related category belongs to the standard access category. Each access belongs to at least one standardized access category. The other is the non-standardized access category. This category is defined outside the 3GPP architecture and therefore is not explicitly classified in standard documents. Therefore, operators have their own operator-specific access categories with different meanings. This is similar to the characteristics of categories in traditional ACDC. However, a specific access triggered by UE NAS may not be mapped to a non-standardized access category. The proposed access control scheme differs from traditional ACDC in that the classification is performed using other elements and applications, such as service access type, call type, UE class, user group, signaling type, slice type, and any combination thereof. For example, access control can be performed on access types specific to certain elements. The aforementioned access categories are used to indicate specific accesses, as shown in Table 9. Access categories 0 to 7 are used to indicate standardized access categories, and access categories 32 to 63 are used to indicate operator-specific access categories.

[0655] [Table 9]

[0656]

[0657]

[0658] The operator's server 7e-25 provides operator-specific access category information (MO) to the UE NAS1e-10 via NAS signaling or application layer data transmission. This information indicates a corresponding element, such as an application. For example, this information could explicitly indicate that access category 32 corresponds to Facebook application access. The gNB 7e-20 uses system information to provide the UE with a list of categories containing prohibited configuration information and the prohibited configuration information for each category. The UE 7e-05 includes logical blocks of NAS 7e-10 and AS7e-15.

[0659] The UE NAS 7e-10 maps triggered accesses to one or more access identifiers and an access class according to predetermined rules. The mapping operation is performed in all RRC states: connected mode (RRC_CONECTED), idle mode (RRC_IDLE), and inactive mode (RRC_INACTIVE). The characteristics of the RRC states are as follows.

[0660] RRC_IDLE:

[0661] -UE-specific DRX can be configured by the upper layer;

[0662] - UE-controlled mobility based on network configuration;

[0663] -UE:

[0664] - Monitor the paging channel;

[0665] - Perform neighboring cell measurements and cell (re)selection;

[0666] - Obtain system information.

[0667] RRC_INACTIVE:

[0668] -UE-specific DRX can be configured by the upper layer or RRC layer;

[0669] - UE-controlled mobility based on network configuration;

[0670] -UE stores AS context;

[0671] -UE:

[0672] - Monitor the paging channel;

[0673] - Perform neighboring cell measurements and cell (re)selection;

[0674] - When moving out of the RAN-based notification area, perform a RAN-based notification area update;

[0675] - Obtain system information.

[0676] RRC_CONNECTED:

[0677] -UE stores AS context.

[0678] - Transmit unicast data to / from the UE.

[0679] - At the lower layer, the UE can be configured with UE-specific DRX;

[0680] - For UEs that support CA, use one or more SCells aggregated with SpCell to increase bandwidth;

[0681] - For UEs that support DC, use an SCG aggregated with MCG to increase bandwidth;

[0682] - Network-controlled mobility, i.e., within the NR and for handover to / from the E-UTRAN.

[0683] -UE:

[0684] - Monitor the paging channel;

[0685] - Monitor the control channel associated with the shared data channel to determine whether data has been scheduled for it;

[0686] - Provides channel quality and feedback information;

[0687] - Perform neighboring cell measurements and measurement reports;

[0688] - Obtain system information.

[0689] Optionally, access can be mapped to a standardized access category, and additionally, to an operator-specific access category. The UE NAS 7e-10 sends the mapped access identifier and access category, along with a service request, to the UE AS 7e-15.

[0690] In this embodiment of the present disclosure, if UE AS 7e-15 receives a message from UE NAS 7e-10 including access identifier or access category information in any of all RRS states, it performs a prohibition check operation to determine whether to allow the corresponding access before attempting radio access triggered by the corresponding message. If the prohibition check operation determines that radio access is allowed, UE AS 7e-15 requests RRC connection establishment from the network. For example, in connected or inactive mode, at operation 7e-30, UE NAS 7e-10 sends the access identifier and access category to UE AS 7e-15 for the following reasons. In this disclosure, the following reasons are collectively referred to as "new session request".

[0691] - New MMTEL voice or video session

[0692] - Send SMS (IP-based SMS or NAS-based SMS)

[0693] - New PDU session established

[0694] - Modify existing PDU sessions

[0695] - Service requests to rebuild the user plane for existing PDU sessions

[0696] However, in idle mode, UE NAS 7e-10 sends the access identifier and access category to UE AS 7e-15 via a service request.

[0697] The UE AS 7e-15 determines whether to allow access triggered by the UE NAS 7e-10 based on the prohibited configuration information (prohibited inspection).

[0698] Operators may wish to allow access to services of a predetermined type corresponding to at least one of access classes 11 to 15. This disclosure is characterized by determining whether access belonging to access classes 11, 12, 13, 14, and 15 is allowed based on the attributes identified by the access class. To achieve this, this disclosure provides a method for configuring prohibition configuration information for access identifiers or access classes. In this disclosure, it is assumed that the access class-specific prohibition configuration information is configured with ac-barringFactor and ac-barringtime, similar to the prohibition configuration information of related technologies such as ACB or ACDC.

[0699] Figure 7F This is a signal flow diagram illustrating the access control process of a UE in connected mode or inactive mode according to an embodiment of the present disclosure.

[0700] refer to Figure 7FUE 7f-05 includes NAS 7f-10 and AS 7f-15. NAS handles operations not directly related to radio access, such as authentication service requests and session management, while AS 7f-15 handles radio access-related operations. At operation 7f-25, network 7f-20 provides MOI to NAS 7f-10 via OAM (Application Layer Data Message) or NAS messages. The MOI indicates an element corresponding to each operator-specific access category, such as an application. NAS 7f-10 uses the MOI to identify the operator-specific category to which triggered access is mapped. Triggered access corresponds to new MMTEL services (voice and video communications), SMS transmissions, new PDU session establishment, changes to previous PDU sessions, etc. If a service is triggered, at operation 7f-30, NAS 7f-10 maps the access identifier corresponding to the attributes of that service to an access category. A service can be mapped to none or at least one access identifier. A service can be mapped to an access category. Under the assumption that a service can be mapped to an access class, NAS 7f-10 determines whether the service is mapped to an operator-specific access class provided in the MO. If the service is not mapped to any operator-specific access class, NAS 7f-10 maps the service to one of the available standardized access classes. Under the assumption that a service can be mapped to multiple access classes, NAS 7f-10 maps the service to both operator-specific and standardized access classes. However, if the service is not mapped to any operator-specific access class, NAS 7f-10 maps the service to one of the available standardized access classes. This mapping rule can be applied except for emergency services. At Operation 7f-40, NAS 7f-10 sends a new session request or service request message to AS 7f-15, including the mapped access identifier and access class. NAS 7f-10 transmits new session requests in connected or inactive mode and service requests in idle mode. At Operation 7f-35, AS 7f-15 receives prohibited configuration information included in system information broadcast by Network 7f-20. The prohibited configuration information is described below. At operation 7f-45, AS determines whether a service request is accepted based on the access identifier and access class information that the NAS has already mapped to the service, as well as the corresponding mapping configuration information received from network 7f-20. If the service request is accepted according to predetermined rules, at operation 7f-50, AS 7f-15 requests RRC connection establishment (RRC connection establishment or RRC connection recovery) from network 7f-20 or sends data related to a new session to network 7f-20.

[0701] Figure 7G This is a flowchart illustrating the operation of a UE NAS according to an embodiment of the present disclosure.

[0702] refer to Figure 7G At Operation 7g-05, the UE NAS receives the MOI from the network via OAM or RRC signaling. The MOI indicates an element, such as an "application" corresponding to each operator-specific access category.

[0703] At operation 7g-10, UE NAS detected one of the following reasons.

[0704] -Access Attempt

[0705] - New MMTEL voice or video session

[0706] - Send SMS (IP-based SMS or NAS-based SMS)

[0707] - New PDU session established

[0708] - Modify existing PDU sessions

[0709] - Service requests to rebuild the user plane for existing PDU sessions

[0710] At Operation 7g-15, the UE NAS maps the access attempt to at least one access identifier and access class. There may not be any corresponding access identifier.

[0711] At Operation 7g-20, the UE NAS sends a new session request / session modification (session management) or a service request that includes mapped access identifier and access category information to the UE AS.

[0712] Figure 7H This is a flowchart illustrating the operation of a UE AS according to an embodiment of the present invention.

[0713] refer to Figure 7H At operation 7h-05, the UE AS receives configuration prohibition information from the network via system information. Configuration prohibition information is provided for each access identifier and access category.

[0714] During operation 7h-10, the UE AS determines whether it has received an access identifier or access class from the UE NAS via a new session request / session modification (session management) or service request. A new session request / session modification (session management) or service request triggers data transmission for RRC connection establishment, RRC connection recovery, or a new session.

[0715] If the access identifier and access class are received from the UE NAS via a new session request / session modification (session management) or service request, then at operation 7h-15, the UE AS performs a prohibition check based on the configuration information corresponding to the access identifier and access class in the prohibition configuration information. Here, the prohibition check is performed regardless of the UE's current RRC state.

[0716] If neither the access identifier nor the access class is received from the UE NAS via a new session request / session modification (session management) or service request, the UE AS will not perform a prohibition check on any data transmission during operation 7h-20. For example, the UE AS will not perform any prohibition checks on initial data transmission and RRC connection recovery not involved in the NAS.

[0717] In this operation, the UE AS only performs prohibition checks on accesses for which the UE NAS provides the access identifier and access category. Meanwhile, there may be accesses triggered by the AS (not involving the NAS). For such accesses, no prohibition checks are performed. If AS-triggered accesses dominate, this can lead to network congestion. Therefore, additional prohibition checks may be needed for AS-triggered accesses. One approach is for the AS to perform separate prohibition checks on AS-triggered accesses. AS-triggered accesses can be categorized by attribute. For example, AS-triggered accesses can fall into one of two types: MO signaling or MO data. The network provides prohibition configuration information for each category applied in connected or inactive modes. Prohibition configurations corresponding to each type of access identifier or access category can be reused. According to embodiments of this disclosure, if a RAN area update is triggered while the UE is in an inactive state, the RAN area update falls into MO signaling. The UE AS uses prohibition configuration information corresponding to the MO signaling to perform prohibition checks. Here, prohibition configuration information corresponding to access category 3 can be reused for prohibition checks.

[0718] This disclosure relates to a prohibition check procedure performed based on access identifier and access category. The prohibition check procedure applies to UEs in idle mode and connected mode.

[0719] The UE NAS maps access to one or more access identifiers and an access class, and sends this mapping to the UEAS. If the access identifier is set to 0, it can be assumed that there are no other mapped access identifiers.

[0720] The UE AS determines whether a received access identifier exists, and if so, the access identifier is set to 0.

[0721] If at least one access identifier is set to a non-zero value, the UE AS performs a prohibition check based on the non-zero access identifier. The UE AS performs the prohibition check based on prohibition configuration information broadcast by the network. The configuration information is used to determine whether access corresponding to that access identifier is allowed. For example, the network may provide information for determining whether access is allowed in the form of a bitmap (each bit of the bitmap is set to on or off) or in the form of probability information (such as a prohibition factor with values ​​ranging from 0 to 1), indicating whether the corresponding access is allowed. If at least one of the non-zero access identifiers is allowed, the UE AS may not perform a prohibition check on the corresponding access based on the access category, and may ultimately determine that access is allowed and perform RRC connection establishment. If a prohibition check is not allowed for the corresponding access identifier, the UE AS may prohibit access and perform additional prohibition checks on the access category and the prohibition configuration information corresponding to that access category to ultimately determine whether access is allowed.

[0722] If an access identifier is received and that access identifier is set to 0, the UE AS performs a prohibition check using the prohibition configuration information corresponding to the received access category. If it is determined that the prohibition check for that access category is allowed, the UE considers access permitted and performs RRC connection establishment.

[0723] Figure 7I This is a block diagram illustrating the configuration of a UE according to an embodiment of the present disclosure.

[0724] refer to Figure 7I The UE includes a radio frequency (RF) processor 7i-10, a baseband processor 7i-20, a storage unit 7i-30, and a controller 7i-40.

[0725] The RF processor 7i-10 has the function of transmitting / receiving signals through a radio channel, such as signal band conversion and amplification. For example, the RF processor 7i-10 up-converts the baseband signal from the baseband processor 7i-20 into an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back into a baseband signal. For example, the RF processor 7i-10 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, and an ADC. Although one antenna is depicted in the figures, the UE may be equipped with multiple antennas. The RF processor 7i-10 may also include multiple RF chains. The RF processor 7i-10 can perform beamforming. For beamforming, the RF processor 7i-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. The RF processor 7i-10 can be configured to support a MIMO scheme, using which the UE can receive signals from multiple layers simultaneously.

[0726] The baseband processor 7i-20 features baseband signal-to-bit string conversion functionality according to the system physical layer standard. For example, in data transmission mode, the baseband processor 7i-20 encodes and modulates the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 7i-20 demodulates and decodes the baseband signal from the RF processor 7i-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 7i-20 encodes and modulates the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs an IFFT on the symbols, and inserts CP into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 7i-20 divides the baseband signal from the RF processor 7i-10 into OFDM symbols, performs an FFT on the OFDM symbols to recover the signal mapped to the subcarriers, and demodulates and decodes the signals to recover the transmitted bit string.

[0727] The baseband processor 7i-20 and RF processor 7i-10 process transmitted and received signals as described above. Therefore, the baseband processor 7i-20 and RF processor 7i-10 can be referred to as a transmitter, receiver, transceiver, or communication unit. At least one of the baseband processor 7i-20 and RF processor 7i-10 may include multiple communication modules for supporting different radio access technologies. At least one of the baseband processor 7i-20 and RF processor 7i-10 may also include multiple communication modules for processing signals in different frequency bands. For example, different radio access technologies may include wireless local area networks (WLANs) (e.g., IEEE 802.11) and cellular networks (e.g., LTE). Different frequency bands may include ultra-high frequency (SHF) bands (e.g., 2.5 GHz and 5 GHz bands) and mmWave bands (e.g., 60 GHz).

[0728] Storage unit 7i-30 stores data, such as basic procedures, applications, and settings information used to operate the UE. Storage unit 7i-30 provides the stored information in response to requests from controller 7i-40.

[0729] Controller 7i-40 controls the overall operation of the UE. For example, controller 7i-40 controls baseband processor 7i-20 and RF processor 7i-10 to transmit and receive signals. Controller 7i-40 writes data to and reads data from storage unit 7i-30. For this purpose, controller 7i-40 may include at least one processor. For example, controller 7i-40 may include a CP for controlling communications and an AP for controlling higher-level programs (such as applications). Controller 7i-40 may include a multi-connection processor 7i-42 for handling operations in multi-connection mode.

[0730] Figure 7J This is a block diagram illustrating the configuration of a gNB according to an embodiment of the present disclosure.

[0731] refer to Figure 7J The gNB includes an RF processor 7j-10, a baseband processor 7j-20, a backhaul communication unit 7j-30, a storage unit 7j-40, and a controller 7j-50.

[0732] The RF processor 7j-10 has the function of transmitting / receiving signals through a radio channel, such as frequency band conversion and amplification of signals. For example, the RF processor 7j-10 up-converts a baseband signal from the baseband processor 7j-20 to an RF band signal and transmits the RF signal via an antenna, and down-converts the RF signal received via the antenna back to a baseband signal. For example, the RF processor 7j-10 may include transmit filters, receive filters, amplifiers, mixers, oscillators, DACs, and ADCs. Although one antenna is depicted in the figures, the gNB may be equipped with multiple antennas. The RF processor 7j-10 may also include multiple RF chains. The RF processor 7j-10 can perform beamforming. For beamforming, the RF processor 7j-10 can adjust the phase and magnitude of the signal to be transmitted / received via antennas or antenna elements. The RF processor 7j-10 can be configured to transmit one or more layers of downlink MIMO operation.

[0733] The baseband processor 7j-20 has baseband signal-to-bit string conversion functionality according to the system physical layer standard. For example, in data transmission mode, the baseband processor 7j-20 performs encoding and modulation on the transmitted bit string to generate complex symbols. In data reception mode, the baseband processor 7j-20 performs demodulation and decoding on the baseband signal from the RF processor 7j-10 to recover the transmitted bit string. When using an OFDM scheme for data transmission, the baseband processor 7j-20 performs encoding and modulation on the transmitted bit string to generate complex symbols, maps the complex symbols to subcarriers, performs IFFT on the symbols, and inserts CP into the symbols to generate OFDM symbols. In data reception mode, the baseband processor 7j-20 divides the baseband signal from the RF processor 7j-10 into OFDM symbols, performs FFT on the OFDM symbols to recover the signal mapped to the subcarriers, and performs demodulation and decoding on the signals to recover the transmitted bit string. The baseband processor 7j-20 and the RF processor 7j-10 process the transmitted and received signals as described above. Therefore, the baseband processor 7j-20 and the RF processor 7j-10 can be referred to as transmitters, receivers, transceivers, or communication units.

[0734] The backhaul communication unit 7j-30 provides an interface for communicating with other nodes in the network. For example, the backhaul communication unit 7j-30 converts bit strings to be sent from the gNB to another node (e.g., another gNB and the core network) into physical signals, and converts physical signals received from another node into bit strings.

[0735] Storage unit 7j-40 stores data such as basic procedures, application programs, and setting information for gNB operation. Storage unit 7j-40 can also store information about bearers established for the UE and measurement results reported by connected UEs. Storage unit 7j-40 can also store information used by the UE when determining whether to enable or disable multiple connections. Storage unit 7j-40 can provide stored data based on requests from controller 7j-50.

[0736] The controller 7j-50 controls the overall operation of the gNB. For example, the controller 7j-50 controls the baseband processor 7j-20, the RF processor 7j-10, and the backhaul communication unit 7j-30 for transmitting and receiving signals. The controller 7j-50 reads and writes data to the storage unit 7j-40. For this purpose, the controller 7j-50 may include at least one processor. The controller 7j-50 may also include a multi-connection processor 7j-52 for handling operations in a multi-connection mode.

[0737] Although preferred embodiments of this disclosure have been described using specific terminology, the specification and drawings are intended to be illustrative rather than restrictive in order to aid in the understanding of this disclosure. It will be apparent to those skilled in the art that various modifications and alterations can be made thereto without departing from the broader spirit and scope of the invention. These embodiments can be combined in whole or in part, if desired. For example, some of the methods presented in this disclosure can be combined for the operation of base stations and terminals. Although these embodiments are directed to LTE / LTE-A systems, it is apparent that they can be applied to other systems (such as 5G or NR systems) to form other alternative embodiments without departing from the spirit and scope of this disclosure.

[0738] Although this disclosure has been shown and described with reference to various embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope of this disclosure as defined by the appended claims and their equivalents.

Claims

1. A method performed by a user equipment (UE) in a communication system supporting dual connectivity, wherein, The method for aggregating the primary cell group (MCG) associated with the first base station and the secondary cell group (SCG) associated with the second base station for the UE includes: Determine the delayed budget; and If the length of the first discontinuous reception DRX period associated with the delay budget differs from the length of the second DRX period associated with the previously transmitted delay budget, UE assistance information including a delay budget report for the delay budget is transmitted to the first base station. The delay budget indicates a preferred value for the variation of the long DRX cycle length associated with the MCG.

2. The method according to claim 1, further comprising: Receive a Radio Resource Control (RRC) reconfiguration message with a long DRX cycle length from the first base station.

3. The method according to claim 2, wherein, The RRC reconfiguration message also includes the short DRX cycle length, duration timer, and DRX inactivity timer.

4. A method performed by a first base station in a communication system supporting dual connectivity, wherein, The method for aggregating a primary cell group (MCG) associated with a first base station and a secondary cell group (SCG) associated with a second base station for a user equipment (UE) includes: Send a Radio Resource Control (RRC) message to the UE, including parameters associated with Discontinuous Reception (DRX); and If the first DRX cycle length associated with the delay budget differs from the second DRX cycle length associated with the previously transmitted delay budget, UE assistance information including a delay budget report for the delay budget is received from the UE. The delay budget indicates a preferred value for the variation of the long DRX cycle length associated with the MCG.

5. The method according to claim 4, in, The parameters associated with DRX include the long DRX period length.

6. The method according to claim 4, wherein, The parameters associated with DRX include short DRX cycle length, duration timer, and DRX inactivity timer.

7. A user equipment (UE) in a communication system supporting dual connectivity, wherein, The UE is configured to aggregate the primary cell group (MCG) associated with the first base station and the secondary cell group (SCG) associated with the second base station. The UE includes: transceiver; and The controller, coupled to the transceiver, is configured to: Determine the delayed budget, and If the length of the first discontinuous reception DRX cycle associated with the delay budget differs from the length of the second DRX cycle associated with the previously transmitted delay budget, UE assistance information including the delay budget for the delay budget is transmitted to the first base station. The delay budget indicates a preferred value for the variation of the long DRX cycle length associated with the MCG.

8. The UE according to claim 7, wherein, The controller is configured to receive a Radio Resource Control (RRC) reconfiguration message from the first base station, which includes a long DRX cycle length.

9. The UE according to claim 8, wherein, The RRC reconfiguration message also includes the short DRX cycle length, duration timer, and DRX inactivity timer.

10. A first base station in a communication system supporting dual connectivity, wherein, For User Equipment (UE), a primary cell group (MCG) associated with a first base station and a secondary cell group (SCG) associated with a second base station are aggregated. The first base station includes: transceiver; and The controller, coupled to the transceiver, is configured to: Send a Radio Resource Control (RRC) message to the UE, including parameters associated with Discontinuous Reception (DRX); and If the first DRX cycle length associated with the delay budget differs from the second DRX cycle length associated with the previously transmitted delay budget, UE assistance information including a delay budget report for the delay budget is received from the UE. The delay budget indicates a preferred value for the variation of the long DRX cycle length associated with the MCG.

11. The first base station according to claim 10, wherein, The parameters associated with DRX include the long DRX period length.

12. The first base station according to claim 10, wherein, The parameters associated with DRX include short DRX cycle length, duration timer, and DRX inactivity timer.

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