Method for cell reselection in idle mode of next generation mobile communication system

Abstract

The present disclosure relates to a communication technology and a system thereof that integrates a 5G communication system that supports a higher data transmission rate over a 4G system and IoT technology. The present disclosure can be applied to smart services based on 5G communication technology and IoT-related technologies (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail business, security and safety-related services, etc.). A communication method for a base station, the method comprising: establishing at least one bearer with a terminal; receiving a downlink packet sent to the terminal; determining a bearer of quality of service (QoS) information mapped to the downlink packet; and sending a downlink packet to the terminal through the determined bearer.

Description

[0001] This application is a divisional application of the invention patent application with the application date of August 2, 2017, application number 201780049041.1, and invention name "Method for cell reselection in idle mode of next-generation mobile communication system". Technical Field

[0002] Various embodiments of the present disclosure relate to operations of a terminal and a base station in a mobile communication system.

[0003] Various embodiments of the present disclosure relate to a method and apparatus for establishing and processing QoS based on user traffic in a next generation mobile communication system.

[0004] Various embodiments of the present disclosure relate to reselection of a serving beam of a terminal in a beam-based NR system, and more particularly, to a method and apparatus for measuring adjacent beams using a differential threshold.

[0005] Various embodiments of the present disclosure are directed to a method for measuring a downlink reference signal in a wireless communication system performing beam-based communication. Background Art

[0006] In order to meet the demand for radio data services, which has been on an upward trend since the commercialization of the 4G communication system, efforts have been made to develop an improved 5G communication system or a pre-5G communication system. For this reason, the 5G communication system or the pre-5G communication system is called a super 4G network communication system or a post-LTE system. In order to achieve a high data transmission rate, the 5G communication system is considered to be implemented in a very high frequency (mmWave) band (for example, similar to the 60GHz band). In the 5G communication system, in order to alleviate the path loss of radio waves and increase the transmission distance of radio waves in the extremely high frequency band, beamforming, massive MIMO, full-size MIMO (FD-MIMO), array antennas, analog beamforming, and massive antenna technology have been discussed. In addition, in order to improve the network of the system, in the 5G communication system, technologies such as evolved small cells, advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device-to-device communication (D2D), wireless backhaul, mobile networks, cooperative communications, coordinated multi-point (CoMP), and reception interference elimination have been developed. Besides this, in 5G systems, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) have been developed as advanced coding modulation (ACM) schemes, filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies, etc.

[0007] Meanwhile, the Internet, a human-centered connected network where humans generate and consume information, is now developing toward the Internet of Things (IoT), which sends and receives information between distributed components such as things and processes the information. The Internet of Everything (IoE), in which IoT technology is combined with big data processing technology, etc. by connecting to cloud servers, etc., has emerged. In order to realize IoT, technical elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology are required. Recently, technologies such as sensor networks, machine-to-machine (M2M), and machine type communication (MTC) have been studied for connection between things. In the IoT environment, intelligent Internet technology (IT) services can be provided that create new value for human life by collecting and analyzing data generated between connected things. Through the integration and combination of existing information technology (IT) with various industrial applications, IoT can be applied to multiple fields such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart appliances, and advanced medical services.

[0008] Therefore, various attempts have been made to apply 5G communication systems to IoT networks. For example, 5G communication technologies such as sensor networks, machine-to-machine (M2M), and machine-type communications (MTC) have been implemented through technologies such as beamforming, MIMO, and array antennas. The application of cloud radio access networks (cloud RAN), which are the above-mentioned big data processing technologies, can also be regarded as an example of the fusion of 5G communication technologies and IoT technologies. Summary of the invention

[0009] Technical issues

[0010] In order to solve the above-mentioned defects, when a method for establishing QoS based on a bearer such as the current LTE system is applied, the main purpose of the present disclosure is to process several groups of flows in a network with the same QoS. Therefore, it is impossible to control QoS more finely at the EPC stage and the E-UTRAN stage. Therefore, in addition to the method for establishing QoS based on a bearer, the present disclosure also proposes a method for establishing QoS based on a flow.

[0011] In addition, in a beam-based NR system, the complexity and cost of the measurement of adjacent beams performed for the terminal to reselect beams are different according to intra-TRP, inter-TRP, and inter-frequency. In addition, since all beams must be measured for a very large number of adjacent beams in order to measure all beams, the consumption cost is high. In the present disclosure, considering the difference in the complexity of the measurement method as described above, an effective process for measuring adjacent beams is defined.

[0012] Therefore, embodiments of the present disclosure are intended to reduce power consumption of a terminal when the terminal intends to continuously search for an optimal beam combination in a wireless communication system that performs beam-based communication.

[0013] The purpose of the present disclosure is not limited to the above-mentioned purpose. That is, those skilled in the art to which the present disclosure belongs can clearly understand other purposes not mentioned from the following description.

[0014] Technical Solution

[0015] According to another aspect of the present disclosure, a communication method of a base station is provided. The method includes: establishing at least one bearer with a terminal; receiving a downlink packet sent to the terminal; determining a bearer of quality of service (QoS) information mapped to the downlink packet; and sending the downlink packet to the terminal through the determined bearer.

[0016] The method also includes: if there is no bearer of QoS information mapped to the downlink packet, establishing a bearer of QoS information mapped to the downlink packet with the terminal; and sending the downlink packet to the terminal via the established bearer of QoS information mapped to the downlink packet.

[0017] The method further includes: if there is no bearer mapped to the QoS information of the uplink packet, receiving the uplink packet from the terminal through a default bearer, and wherein the uplink packet includes a QoS tag indicating the QoS information of the uplink packet.

[0018] The method further includes: establishing a bearer of QoS information mapped to uplink packets with the terminal.

[0019] In the method, determining the bearer of QoS information mapped to a downlink packet is performed by a layer above a PDCP (Packet Data Convergence Protocol) layer.

[0020] According to another aspect of the present disclosure, a communication method of a terminal is provided. The method includes: establishing at least one bearer with a base station; and receiving a downlink packet from the base station through the bearer mapped to Quality of Service (QoS) information of the downlink packet.

[0021] The method also includes: if there is no bearer of QoS information mapped to the downlink packet, establishing a bearer of QoS information mapped to the downlink packet with the base station; and receiving the downlink packet from the base station through the established bearer of QoS information mapped to the downlink packet.

[0022] The method further includes: if there is no bearer mapped to the QoS information of the uplink packet, uplinking the packet to the base station through a default bearer, and wherein the uplink packet includes a QoS tag indicating the QoS information of the uplink packet.

[0023] The method further includes: establishing a bearer of QoS information mapped to uplink packets with a base station.

[0024] In the method, sending an uplink packet also includes: determining a bearer of QoS information mapped to the uplink packet, and marking the QoS information of the uplink packet in the uplink packet, and wherein determining the bearer of QoS information mapped to the uplink packet and marking the QoS information of the uplink packet in the uplink packet are performed by a layer above the PDCP (Packet Data Convergence Protocol) layer.

[0025] According to another aspect of the present disclosure, a base station is provided. The base station includes: a transceiver configured to send and receive signals; a controller coupled to the transceiver and configured to establish at least one bearer with a terminal, receive a downlink packet sent to the terminal, determine a bearer of QoS (Quality of Service) information mapped to the downlink packet, and send the downlink packet to the terminal through the determined bearer.

[0026] According to another aspect of the present disclosure, a terminal is provided. The terminal includes: a transceiver configured to send and receive signals; a controller coupled to the transceiver and configured to establish at least one bearer with a base station, and receive a downlink packet from the base station through a bearer mapped to QoS (Quality of Service) information of the downlink packet.

[0027] Beneficial Effects

[0028] According to the present disclosure, if the method for establishing a bearer-based QoS is applied as in the current LTE system, several groups of flows are treated as the same QoS in the network. Therefore, it is impossible to control the QoS more finely in the EPC stage and the E-UTRAN stage. However, if the method for establishing a flow-based QoS proposed in the present disclosure is applied, it is possible to control the QoS more finely on a flow basis and provide a systematic QoS for each service.

[0029] In addition, according to the present disclosure, if the method for measuring differential adjacent beams proposed in the present disclosure is applied to a beam-based NR system, not all adjacent beams are measured, so the time required for adjacent beam measurement can be reduced. That is, the process of measuring adjacent beams is simplified, which reduces the time for the terminal to reselect the serving beam.

[0030] In addition, according to the present disclosure, the terminal determines appropriate transmit beams and receive beams, and can then measure the strength and quality of the reference signal according to a predetermined downlink receive beam configuration in a predetermined period without continuously measuring all beams, thereby reducing power consumption of the terminal.

[0031] The effects that can be achieved by the embodiments of the present disclosure are not limited to the above-mentioned effects. That is, those skilled in the art to which the present disclosure belongs can clearly understand other effects that are not mentioned from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals represent like parts:

[0033] Figure 1 The structure of a next generation mobile communication system according to an embodiment of the present disclosure is shown;

[0034] Figure 2 The basic structure of the time-frequency domain of the LTE and LTE-A systems according to the embodiments of the present disclosure is shown;

[0035] Figure 3 Example 1 (subcarrier spacing of 15 KHz) of an extended frame structure according to an embodiment of the present disclosure is shown;

[0036] Figure 4 Example 2 (30KHz subcarrier spacing) of an extended frame structure according to an embodiment of the present disclosure is shown;

[0037] Figure 5 Example 3 (60KHz subcarrier spacing) of an extended frame structure according to an embodiment of the present disclosure is shown;

[0038] Figure 6 An example of a multiplexing extension frame structure according to an embodiment of the present disclosure is shown;

[0039] Figure 7 An example of a process of sending priority information of each frequency for cell reselection in LTE technology to a terminal and applying the priority information according to an embodiment of the present disclosure is shown;

[0040] Figure 8 A method for a terminal to perform cell reselection according to signal strength according to an embodiment of the present disclosure is shown;

[0041] Fig. 9 An example of a configuration supporting numerology according to an embodiment of the present disclosure is shown;

[0042] Fig.10 A process of performing cell reselection according to an embodiment of the present disclosure is shown;

[0043] Fig.11 illustrates the operation of a terminal according to an embodiment of the present disclosure;

[0044] Fig.12 Showing the configuration of a terminal according to an embodiment of the present disclosure;

[0045] Fig.13 Showing the configuration of a base station according to an embodiment of the present disclosure;

[0046] Fig.14 An example of a network structure of an LTE system according to an embodiment of the present disclosure is shown;

[0047] Fig.15 The radio protocol structure in the LTE system according to the embodiment of the present disclosure is shown;

[0048] Fig.16 A detailed example of a network structure of a wireless communication system according to an embodiment of the present disclosure is shown;

[0049] Fig.17a and Fig.17b A method for establishing bearer-based QoS in a wireless communication system according to an embodiment of the present disclosure is shown;

[0050] Fig.18 A method for establishing flow-based QoS in a next-generation wireless communication system according to an embodiment of the present disclosure is shown;

[0051] Fig.19 A signaling process of allocating a QoS policy including QoS mapping information to each flow or allocating information about packet marking to a base station and a terminal in a method for establishing flow-based QoS according to an embodiment of the present disclosure is shown;

[0052] Fig. 20 The process of establishing a bearer and sending downlink data in a method for establishing a flow-based QoS according to an embodiment of the present disclosure is shown;

[0053] Fig.21 The process of establishing a bearer and sending uplink data by a terminal in a method for establishing a flow-based QoS according to an embodiment of the present disclosure is shown;

[0054] Fig. 22 An example of the operation of a base station in a method for establishing flow-based QoS according to an embodiment of the present disclosure is shown;

[0055] Fig.23 An example of the operation of a terminal in a method for establishing flow-based QoS according to an embodiment of the present disclosure is shown;

[0056] Fig.24The configuration of a terminal and a configuration of a base station applied to the method for establishing a flow-based QoS according to an embodiment of the present disclosure are shown;

[0057] Figure 25 to Figure 27 The configuration of the terminal when the terminal to which the method for establishing flow-based QoS according to the embodiment of the present disclosure can be applied interacts with the LTE system and the next generation wireless communication system;

[0058] Fig.28 A scenario of interaction between a base station (rNB) of a next generation wireless communication system and a base station (eNB) of an LTE system to which a method for establishing flow-based QoS according to an embodiment of the present disclosure is applied is shown;

[0059] Fig.29 Another scenario of interaction between a base station (rNB) of a next generation wireless communication system and a base station (eNB) of an LTE system to which the method for establishing flow-based QoS according to an embodiment of the present disclosure is applied is shown;

[0060] Fig.30 Showing the configuration of a terminal according to an embodiment of the present disclosure;

[0061] Fig.31 The configuration of a base station, an MME and an S-GW according to an embodiment of the present disclosure is shown;

[0062] Fig.32 The structure of the NR system according to the embodiment of the present disclosure is shown;

[0063] Fig.33 A frame structure of an NR system operating in a beam-based manner according to an embodiment of the present disclosure is shown;

[0064] Fig.34 The process of reselecting a cell in an LTE system by a terminal according to an embodiment of the present disclosure is shown;

[0065] Fig.35 A method for a terminal to reselect a serving beam in an NR system according to an embodiment of the present disclosure is shown;

[0066] Fig.36 Example 1 of beam measurement of an NR system according to an embodiment of the present disclosure is shown;

[0067] Fig.37 and Fig.38 Example 2 of beam measurement of an NR system according to an embodiment of the present disclosure is shown;

[0068] Fig.39 The operation of the terminal of Example 2 for the terminal to reselect a serving beam in an NR system according to an embodiment of the present disclosure is shown;

[0069] Fig.40shows the configuration of a terminal according to an embodiment of the present disclosure;

[0070] Fig.41 The configuration of a base station according to an embodiment of the present disclosure is shown;

[0071] Fig.42 An example of a network structure of an LTE system according to an embodiment of the present disclosure is shown;

[0072] Fig.43 The radio protocol structure of the LTE system according to the embodiment of the present disclosure is shown;

[0073] Fig.44 An example of a frame structure of a 5G system using an embodiment of the present disclosure is shown;

[0074] Fig.45 A beam adjustment method according to an embodiment of the present disclosure is shown;

[0075] Fig.46 The message flow between the terminal and the base station when the beam adjustment method according to the embodiment of the present disclosure is used is shown;

[0076] Fig.47 The following is a flow diagram showing an operation of a terminal according to an embodiment of the present disclosure;

[0077] Fig.48 shows the configuration of a terminal according to an embodiment of the present disclosure;

[0078] Fig.49 The structure of a next generation mobile communication system according to an embodiment of the present disclosure is shown;

[0079] Fig.50 shows beam scanning of an NR system according to an embodiment of the present disclosure;

[0080] Fig.51 The subframe structure of the NR system according to an embodiment of the present disclosure is shown;

[0081] Fig.52 Shows the overall operation according to an embodiment of the present disclosure;

[0082] Fig.53 illustrates the operation of a terminal according to an embodiment of the present disclosure;

[0083] Fig.54 shows the configuration of a terminal according to an embodiment of the present disclosure; and

[0084] Fig.55 The configuration of a base station according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0085] Before proceeding to the following detailed description, it may be helpful to set forth definitions of certain words and phrases used in this patent document: the terms "include" and "comprising" and their derivatives mean including but not limiting; the term "or" is inclusive, meaning and / or; the phrases "associated with" and "associated with" and their derivatives may mean including, included therein, interconnected therewith, containing, contained therein, connected to or connected therewith, coupled to or coupled therewith, communicating with, cooperating with, interleaved, juxtaposed, proximate, bound to or bound therewith, having, having the property of, and the like; and the term "controller" means any device, system, or portion thereof that controls at least one operation, such device being implemented in hardware, firmware, or software, or some combination of at least two thereof. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided in this patent document, and those of ordinary skill in the art should understand that in many, if not most, cases, such definitions apply to prior and future uses of such defined words and phrases.

[0086] The following discussion Figures 1 to 55 The various embodiments used to describe the principles of the present disclosure in this patent document are exemplary only and should not be interpreted in any way as limiting the scope of the present disclosure. Those skilled in the art will understand that the principles of the present disclosure can be implemented in any suitably arranged electronic device.

[0087] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. When it is determined that a detailed description of a known function or configuration related to the present disclosure may obscure the subject matter of the present disclosure, its detailed description will be omitted. In addition, the following terms are defined in consideration of the functions in the present disclosure, and these terms may be interpreted in different ways by the intention or practice of users and operators. Therefore, their definitions should be interpreted based on the content in the entire specification.

[0088] According to the following detailed description of the embodiments with reference to the accompanying drawings, various advantages and features of the present disclosure and methods for achieving the advantages and features will become apparent. However, the present disclosure is not limited to the embodiments disclosed herein, but will be implemented in various forms. The embodiments make the disclosure of the present disclosure complete and are provided so that those skilled in the art can easily understand the scope of the present disclosure. Therefore, the present disclosure will be limited by the scope of the attached claims. The same reference numerals throughout the specification represent the same elements.

[0089] It should be understood that when a component is referred to as being "connected to" or "coupled to" another component in this specification, it may mean that one component is directly connected to or directly coupled to another component, or is electrically connected to or coupled to another component through other components interposed therebetween. In addition, in this specification, "comprising" a specific configuration will be understood as additional configurations may also be included within the scope of the embodiments or technical concepts of the present disclosure.

[0090] In addition, the components shown in the embodiments of the present disclosure are shown independently to represent different characteristic functions. Therefore, it does not mean that each component is composed of separate hardware or one software. That is, for ease of description, each component is included by being arranged as each component, and at least two components of each component can form a component, or a component is divided into multiple components to perform functions. Unless it departs from the essence of the present disclosure, the integrated embodiments and separate embodiments of the various components are also included in the scope of the present disclosure.

[0091] In addition, some components may not be essential components for performing the basic functions of the present disclosure, but are selective components that only improve their performance. In addition to components for improving performance, the present disclosure can be realized by only including essential constituent parts for realizing the essence of the present disclosure. In addition to selective components for only improving performance, structures that only include essential components are also included in the scope of the present invention.

[0092] Hereinafter, when it is determined that the detailed description of the known technology related to the present disclosure may obscure the subject matter of the present disclosure when describing the embodiments of the present disclosure, its detailed description will be omitted. Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, the following terms are defined in consideration of the functions in the present disclosure, and these terms may be interpreted in different ways by the intention or practice of the user and operator. Therefore, their definitions should be interpreted based on the contents in the entire specification.

[0093] In this case, it is understood that each block of the processing flow chart and the combination of the flow chart can be performed by computer program instructions. Since these computer program instructions can be installed in a processor for a general-purpose computer, a special computer or other programmable data processing device, these instructions executed by the processor for the computer or other programmable data processing device create a device for performing the functions described in the blocks of the flow chart. Since these computer program instructions can also be stored in a computer-usable or computer-readable memory of a computer or other programmable data processing device to implement the functions in a specific scheme, the computer program instructions stored in the computer-usable or computer-readable memory can also produce and manufacture articles, including instruction devices for performing the functions described in the blocks of the flow chart. Since the computer program instructions can also be installed on a computer or other programmable data processing device, a series of operating steps are performed on the computer or other programmable data processing device to create a process executed by the computer to perform the instructions of the computer or other programmable data processing device can also provide steps for performing the functions described in the blocks of the flow chart.

[0094] Here, the term "~unit" used in the present embodiment represents software or hardware components such as FPGA and ASIC, and the "~unit" performs any role. However, the meaning of "~unit" is not limited to software or hardware. "~unit" can be configured in a storage medium that can be addressed, and can also be configured to reproduce one or more processors. Therefore, for example, "~unit" includes components (such as software components, object-oriented software components, class components and task components) and processors, functions, attributes, processes, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays and variables. The functions provided in components and "units" can be combined with a smaller number of components and "~units", or can be further divided into additional components and "~units". In addition, components and "~units" can also be implemented to reproduce one or more CPUs in a device or a secure multimedia card.

[0095] Hereinafter, if it is determined that the detailed description of known technologies related to the present disclosure may obscure the gist of the present disclosure, the detailed description thereof will be omitted. Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0096] In recent years, in order to handle the explosive growth of mobile data services, the fifth generation (5G) system or new radio access technology (NR) is the next generation telecommunication system since the long term evolution (LTE) or evolved universal terrestrial radio access (E-UTRA) and LTE advanced (LTE-A) or E-UTRA evolution have been actively discussed. The existing mobile communication system focuses on typical voice / data communication, while the 5G system aims to meet various services such as enhanced mobile broadband (eMBB) service for enhancing existing voice / data communication, ultra-reliable / ultra-low latency communication (URLLC) service, and machine type communication (massive MTC) service for supporting large-scale communication required by the Internet of Things and requirements.

[0097] Figure 1 The structure of a next generation mobile communication system according to the present disclosure is shown.

[0098] Reference Figure 1 , the radio access network of the next generation mobile communication system includes a next generation base station (new radio node B (NR NB) or gNB, etc.) 110 and a next generation core network (new radio core network (NR CN), access and mobility management function (AMF), user plane function (UPF), session management function (SMF), etc.) 120. The user terminal (new radio user equipment (NR UE) or terminal (UE)) 130 can be connected to an external network via the NR NB 110 and the NR CN 120.

[0099] At the same time, Figure 1 In the present invention, NR NB 110 may correspond to a base station (evolved Node B (eNB)) 140 of an existing LTE system. NR NB 110 is connected to NR UE 130 via a radio channel and may provide services superior to those of the existing Node B (base station) 140. In the next generation mobile communication system, since all user services are served through a shared channel, a device is required for collecting status information to perform scheduling, such as a buffer status, available transmission power status, and channel status of UE 130. NR NB 110 may play the role of the device. One NR NB 110 may typically control multiple cells.

[0100] In order to achieve ultra-high-speed data transmission compared with the existing LTE, the next-generation mobile communication system may have a bandwidth equal to or greater than the maximum bandwidth of the existing LTE, and may additionally apply a beamforming technology using orthogonal frequency division multiplexing (OFDM) as a radio access technology. In addition, an adaptive modulation and coding (hereinafter referred to as AMC) scheme for determining a modulation scheme and a channel coding rate according to a channel state of the terminal 130 may be applied. The NR CN 120 may perform functions such as mobility support, bearer establishment, QoS setting, and the like. The NR CN 120 is a device for performing various control functions of the terminal 130 and a mobility management function, and may be connected to a plurality of base stations 110.

[0101] In addition, the next generation mobile communication system can even interact with the existing LTE system, and the NR CN 120 can be connected to the MME 150 through a network interface according to an embodiment. The MME 150 is connected to the eNB 140, which is a base station of the existing LTE.

[0102] The system transmission bandwidth of each single carrier of the existing LTE and LTE-A is limited to a maximum of 20MHz, while the 5G system aims to provide ultra-high-speed data services of several Gbps using an ultra-wide bandwidth wider than this. As a result, the 5G system considers very high frequency bands from several GHz to 100GHz as candidate frequencies, and it is relatively easy to secure ultra-wideband frequencies. In addition, a method for securing wideband frequencies for the 5G system is also being considered by reallocating or allocating frequencies in the frequency bands of several hundred MHz to several GHz used in the existing mobile communication system.

[0103] Radio waves in the very high frequency band have a wavelength of about several millimeters, and are therefore sometimes referred to as millimeter waves (mmWave). However, in the very high frequency band, the path loss of radio waves increases in proportion to the frequency band, making the coverage of the mobile communication system smaller.

[0104] In order to overcome the disadvantage of reduced coverage of the extremely high frequency band, beamforming technology, which concentrates the radiation energy of radio waves to a predetermined destination by using multiple antennas to increase the reach of radio waves, becomes more important. Beamforming technology can be applied to the transmitting end and the receiving end respectively. In addition to increasing the coverage, beamforming technology also reduces interference in areas other than the beamforming direction. In order for the beamforming technology to operate properly, a method for accurately measuring and feeding back the transmit / receive beam is required.

[0105] As another requirement of the 5G system, there is an ultra-low latency service with a transmission delay of about 1ms between the transmitting end and the receiving end. As a method for reducing transmission delay, there may be a frame structure design based on a short transmission time interval (TTI) compared to LTE and LTE-A. TTI is a basic unit for performing scheduling, and the TTI of LTE and LTE-A systems is 1ms, corresponding to the length of one subframe. For example, a short TTI that meets the requirements of ultra-low latency services of the 5G system can be 0.5ms, 0.2ms, 0.1ms, etc., which is shorter than that of LTE and LTE-A systems. In the following description, unless otherwise specified, one TTI and subframe are the basic units of scheduling and are used interchangeably with each other as meanings of a predetermined time interval.

[0106] Hereinafter, the frame structures of LTE and LTE-A systems will be described with reference to the accompanying drawings, and the design direction of the 5G system will be described.

[0107] Figure 2 The basic structure of a time-frequency resource region according to the present disclosure is shown, where the time-frequency resource region is a radio resource region for transmitting data or control channels of LTE and LTE-A systems.

[0108] Reference Figure 2 , the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The uplink (UL) represents a radio link through which a terminal sends data or a control signal to a base station, and the downlink (DL) represents a radio link through which a base station sends data or a control signal to a terminal. The minimum transmission unit in the time domain of the existing LTE and LTE-A systems is an OFDM symbol in the downlink and an SC-FDMA symbol in the uplink. In addition, N symb 230 symbols are grouped together to form a time slot 220, and two time slots 220 are grouped together to form a subframe 210. The length of the time slot 220 is 0.5 ms and the length of the subframe 210 is 1.0 ms. In addition, the radio frame 205 is a time domain unit consisting of 10 subframes. The minimum transmission unit in the frequency domain is a subcarrier with a unit of 15 kHz (the subcarrier spacing is 15 kHz), and the entire system transmission bandwidth consists of a total of N BW The subcarriers consist of 240.

[0109] The basic unit of resources in the time-frequency domain is a resource element (RE) 270, and can be represented by an OFDM symbol index or an SC-FDMA symbol index and a subcarrier index. A resource block (RB) 250 (or a physical resource block (PRB)) is represented by N in the time domain. symb consecutive OFDM symbols or SC-FDMA symbols 230 and N in the frequency domain RB Thus, one RB 250 is defined by N consecutive subcarriers 260.symb x N RB It consists of 270 REs.

[0110] In LTE and LTE-A systems, data is mapped in RB units, and the base station performs scheduling for a predetermined terminal in RB pair units configuring one subframe. The number of SC-FDMA symbols or the number of OFDM symbols N can be determined according to the length of a cyclic prefix (CP) added to each symbol to prevent inter-symbol interference. symb 230. For example, if normal CP is applied, then N symb =7, if scalable CP is applied, then N symb =6. Scalable CP is applied to systems with a relatively longer radio wave transmission distance than normal CP, thereby maintaining inter-symbol orthogonality. The CP length per symbol can be additionally adjusted so that a subframe is configured to an integer number of symbols. For example, in the case of normal CP, the CP length of the first symbol of each time slot 220 is 5.21usec, and the CP length of the remaining symbols in the time slot is 4.69usec. Since the OFDM symbol length has an inverse relationship with the subcarrier spacing, the length of each OFDM symbol is 1 / 15kHz=66.67usec, and if the OFDM symbol length includes the CP length, the length of the first symbol of each time slot 220 is 71.88usec and the length of the remaining symbols of each time slot is 71.36usec. If this is represented by a mathematical expression, the symbol length T_I of the lth symbol can depend on the following equation 1.

[0111]

Mathematical formula 1

[0112] T l =T cp，l +T symb

[0113]

[0114] Subcarrier spacing, CP length, etc. are basic information for OFDM transmission and reception and need to be recognized as common values ​​by a base station and a terminal in order to smoothly transmit and receive signals.

[0115] N BW 240 and N RB 260 is proportional to the system transmission bandwidth. The data rate increases in proportion to the number of RBs scheduled for the terminal.

[0116] The frame structure of the LTE and LTE-A systems described above is designed in consideration of normal voice / data communication and has limitations in scalability to meet various services and requirements such as the 5G system. Therefore, the 5G system needs to flexibly define and operate the frame structure in consideration of various services and requirements.

[0117] As mentioned above, since the operating frequency band of the 5G system is as wide as several hundred MHz to 100GHz, if a single frame structure is operated over the entire frequency band, transmission and reception suitable for the channel environment of each frequency band may be difficult. That is, the 5G system subdivides the operating frequency band, and thus operates a frame structure that defines the subcarrier spacing, so as to efficiently send and receive signals. For example, in order to overcome the performance degradation caused by phase noise in the high frequency band, it is preferred to keep the subcarrier spacing relatively large. In addition to the operating frequency band, even the cell size can be a major consideration in defining the frame structure. For example, when the cell size is large, a relatively long CP length may be preferably applied to avoid inter-symbol interference due to multipath propagation signals. In the following, for ease of explanation, the frame structure defined according to various scenarios such as the operating frequency band and the cell size will be referred to as a scalable frame structure.

[0118] The main purpose of the present disclosure is to define a basic parameter set (in the present disclosure, the set is referred to as numerology) that defines a scalable frame structure for each operation scenario and maintain compatibility between the basic parameter sets to achieve effective system operation. The basic parameter set may be a set of values ​​applied to mobile communications and may include, for example, subcarrier spacing, CP length, frequency bandwidth, subframe length, etc. The operation scenario may be defined based on service types such as operating frequency band, cell size, eMBB, URLLC, and large-scale MTC.

[0119] In a 5G system, multiple numerologies may exist and may coexist in one cell. A cell may support at least one numerology, and the cell will need to effectively notify the terminals within the service area of ​​the cell of the supported numerologies. A set of numerologies may be configured by several elements, i.e., a combination of frequency bandwidth, subcarrier spacing, cyclic prefix (CP) length, subframe length, etc. Therefore, there will be many possible numerologies. Therefore, it is necessary to optimize the notification of numerologies supported by the cell to the terminal in terms of signaling overhead. Therefore, according to the present disclosure, a method for effectively signaling numerologies supported by a cell will be described.

[0120] On the other hand, since it is very inefficient in terms of complexity and cost for a terminal to support all combinations of numerologies, only a few numerologies may be supported, taking into account the usage of each terminal, the numerologies of the cells provided by the main contract operator, features, etc. This means that when a mobile terminal reselects a serving cell, it is necessary to consider the numerologies supported by the cell newly residing in the numerology supported by the terminal. Therefore, the present disclosure is characterized in that, in addition to the signal quality and frequency priority provided by the operator when reselecting a cell, the terminal also considers the numerology.

[0121] Figures 3 to 5 Examples 1 to 3 of scalable frame structures according to an embodiment of the present disclosure are shown.

[0122] As an example, Figures 3 to 5 It shows a case where a basic parameter set defining a scalable frame structure includes a subcarrier spacing, a CP length, a subframe length, etc.

[0123] In the early stages of introducing the 5G system, at least coexistence or dual-mode operation with the existing LTE / LTE-A system is expected. In this way, the existing LTE and LTE-A systems can be used to provide stable system operations, and the 5G system can be used to provide enhanced services. Therefore, the scalable frame structure of the 5G system needs to include at least the frame structure or basic parameter set of LTE and LTE-A.

[0124] Figure 3 The 5G frame structure is similar to the frame structure or basic parameter set of LTE and LTE-A. Figure 3 In frame structure type A, the subcarrier spacing is 15 kHz, a 1 ms subframe consists of 14 symbols, and a PRB consists of 12 subcarriers (=180 kHz=12×15 kHz).

[0125] Reference Figure 4 In frame structure type B, the subcarrier spacing is 30kHz, a 0.5ms subframe consists of 14 symbols, and a PRB consists of 12 subcarriers (=360kHz=12×30kHz). That is, it can be seen that the subcarrier spacing and PRB size of frame structure type B are twice that of frame structure type A, and the subframe length and symbol length of frame structure type B are half of those of frame structure type A.

[0126] Reference Figure 5In frame structure type C, the subcarrier spacing is 60kHz, a 0.25ms subframe consists of 14 symbols, and a PRB consists of 12 subcarriers (=720kHz=12×60kHz). That is, it can be seen that the subcarrier spacing and PRB size of frame structure type C are four times that of frame structure type A, and the subframe length and symbol length of frame structure type C are one quarter of those of frame structure type A.

[0127] That is, if the frame structure type is generalized, for each type, the subcarrier spacing, CP length, subframe length, etc. as the basic parameter set have an integer multiple relationship with each other, so that high scalability can be provided. In addition, as with the characteristics of the LTE frame structure, under the defined frame structure, the CP length of some symbols in the subframe may be different from the CP length of the remaining symbols in the subframe.

[0128] The exemplary frame structure types can be applied corresponding to various scenarios. In terms of cell size, as the CP length increases, cells with larger sizes can be supported, so that frame structure type A can support relatively larger cells than frame structure types B and C. In terms of operating frequency bands, as the subcarrier spacing increases, it is more conducive to recovering phase noise in the high frequency band, so that frame structure type C can support relatively higher operating frequencies than frame structure types A and B. In terms of services, in order to support ultra-low latency services such as URLLC, it is advantageous to make the subframe length shorter, and therefore, frame structure type C is relatively more suitable for URLLC services than frame structure types A and B.

[0129] In addition, a scenario in which frame structure types are multiplexed in one system and operated as a whole can be considered.

[0130] Figure 6 An example of a multiplexing extension frame structure according to an embodiment of the present disclosure is shown.

[0131] Figure 6 Show Figures 3 to 5 The example of frame structure type A 610, frame structure type B 612 and frame structure type C 630 multiplexed in one system is shown in FIG. That is, by maintaining the integer multiple relationship between the basic parameter sets defining the frame structure types, even in the case of Figure 6 In the case of multiplexing as shown, resource mapping within a subframe or PRB can also be performed smoothly.

[0132] Figure 7 An example of a process of transmitting priority information of each frequency for cell reselection in LTE technology to a terminal and applying the priority information according to the present disclosure is shown.

[0133] Reference Figure 7In LTE technology, priority information of each frequency for cell reselection may be broadcast through a system information block (SIB), or may be sent to a specific terminal through a radio resource control (RRC) connection release message which is dedicated RRC signaling and applied.

[0134] Cell reselection is the process of reselecting a serving cell so that the mobile terminal can connect to the cell with the best channel state. The network assigns priorities on each frequency and controls the cell reselection of the terminal in idle mode. For example, if a terminal receives priority information about two frequencies f1 and f2 and f1 has a higher priority than f2, the probability that the terminal will remain at f1 increases. In addition, even if the terminal stays at f2, if the channel state of f2 is not good, the terminal will try to change to f1. Priority information about the frequency can be broadcast through the SIB, or can be provided to a specific terminal through an RRC connection release message as a dedicated RRC signaling. Even if the terminal has priority information about the frequency in advance through the SIB, if the terminal receives UE-specific priority information provided by RRC signaling, the priority information about the SIB can be ignored. Priority information about each frequency is sent through the following cell reselection priority information element (IE), for example, one of the eight assigned priorities. The lower the value, the lower the priority becomes. For example, "0" can represent the lowest priority.

[0135] CellReselectionPriority Information Elements

[0136] --ASN1START

[0137] CellReselectionPriority::=INTEGER(0..7)

[0138] --ASN1STOP

[0139] Frequencies between radio access technologies (RATs) may not be assigned the same priority. If the idle state of the terminal is "staying in any cell state", the terminal applies the frequency priority information received through the SIB and may only store the priority information received from the RRC signaling without using the priority information. On the other hand, the cellReselectionPriority IE is an optional IE that may not exist. In this case, priority information about the corresponding frequency is not assigned. At this time, the terminal may regard the priority of the corresponding frequency as the lowest level.

[0140] In step 710, the terminal may receive priority information about frequencies used not only in EUTRA but also in other RATs through SIB. However, it is not necessary to provide the terminal with priority information about all frequencies. Priority information about the frequency of the currently camped serving cell may also not be provided to the terminal.

[0141] In step 715, the terminal may confirm whether the priority information about the frequency of the current serving cell exists in the SIB. If the priority information about the frequency of the current serving cell is not provided, then in step 720, the terminal may regard the priority on the current frequency as the lowest level.

[0142] The terminal may apply the priority information on each frequency received through the SIB and / or the priority information on the current frequency determined in step 720 in step 725 .

[0143] If the terminal receives an RRC connection release message from the base station, the terminal switches from the connected mode to the idle mode. At this time, the RRC message may include priority information about the frequency. The priority information is UE-specific information and may preferably be applied to the frequency priority information received from the SIB. Therefore, in step 730, the terminal may confirm whether there is frequency priority information (e.g., UE-specific cell reselection priority information) in the RRC message (e.g., RRC connection release message).

[0144] If the frequency priority information exists in the RRC message, the terminal may apply the T 320 value included in the RRC message to drive a timer in step 735 .

[0145] In step 740, the terminal may determine whether the current standby mode state is "camped in any cell state" or "normal camped state". "Normal camped state" refers to a state in which the terminal camps in a suitable cell. A suitable cell is a cell that can provide normal services to the terminal and is a cell that meets the following detailed conditions: corresponds to a public land mobile network (PLMN) selected by the cell (selected PLMN), a registered PLMN, or one of the PLMNs in an equivalent PLMN list; the cell is not prohibited; a cell that meets the cell selection criteria; if the cell is a closed subscriber group (CSG) cell, a cell in which the corresponding CSG ID exists in the terminal's white list.

[0146] In addition, "camped in any cell state" refers to a state in which the terminal camps in an acceptable cell because the terminal does not camp in a suitable cell. In an acceptable cell, normal service is impossible, and the terminal can only attempt an emergency call. An acceptable cell is a cell that satisfies the following conditions: the cell is not barred; and the cell satisfies the cell selection criteria.

[0147] If the terminal is in the "camped on any cell state" idle state, the terminal returns to step 725 instead of the priority information received from the RRC connection release message and applies the frequency priority information received from the SIB.

[0148] However, if the terminal is in the "normal camp" idle state, the terminal determines whether at least one of the following three conditions 747 is met in step 745. The three conditions 747 are as follows: the terminal switches to the connected mode; the T320 timer expires; and the PLMN selection process is performed according to the non-access stratum (NAS) request.

[0149] If any of the above conditions are met, the terminal discards the priority information received from the RRC connection release message in step 750 and returns to step 725 to apply the frequency priority information received from the SIB. Otherwise, if any condition is not met, the terminal may apply the priority information received from the RRC connection release message in step 755.

[0150] Frequency priority information affects the terminal's measurement of a specific frequency. The terminal can always perform measurements with a higher frequency priority than the current serving cell. On the other hand, other frequencies with a priority equal to or lower than the same frequency as the serving cell or the frequency of the serving cell may not always perform measurements on the corresponding frequency to save terminal power. At this time, whether to perform measurements on the corresponding frequency can be performed when the channel service quality (QoS) of the serving cell is less than or equal to a specific threshold. Cell reselection is performed to move the terminal to a cell with a good channel state. However, because the channel QoS of the current serving cell is good, there is no reason for the terminal to move to a frequency with the same priority or lower priority. Therefore, in order to reduce power consumption due to unnecessary channel measurements of the terminal, it is determined based on a specific threshold whether the terminal performs measurements on the corresponding frequency. In the case of intra-frequency, if the QoS of the serving cell is equal to or lower than a specific threshold Sintrasearch, the terminal can perform channel measurements on other cells within the frequency. For other frequencies with the same priority or lower priority, when the QoS of the serving cell is equal to or lower than a specific threshold Snonintrasearch, the terminal can perform channel measurements on cells of different frequencies. Channel QoS usually takes into account reference signal received power (RSRP) and reference signal received quality (RSRQ).

[0151] If the channel QoS of the cell of the high priority frequency becomes higher than a specific threshold ThreshX-high while the terminal performs measurement, the terminal can reselect the cell of the high priority frequency as the serving cell. If the channel QoS of the cell of the low priority frequency is higher than a specific threshold ThreshX-low and the QoS of the serving cell is lower than ThreshServing-low, the terminal can reselect the cell of the low priority frequency as the serving cell.

[0152] Figure 8 A method in which a terminal performs cell reselection according to signal strength according to the present disclosure is shown.

[0153] Reference Figure 8 , the terminal always performs inter-frequency / inter-RAT measurements on a higher priority frequency or RAT, regardless of the measured signal strength of the serving cell 810. If the measured signal strength of the serving cell 810 is lower than a first threshold (e.g., SintraSearch) 870, the terminal may perform intra-frequency measurements. If the measured signal strength of the serving cell 810 is lower than a second threshold (e.g., SnonintraSearch) 850, the terminal may set inter-frequency / frequency measurements on a frequency equal to or lower than the frequency of the current serving cell. The reason for gradually triggering the terminal measurement is to reduce the power consumption of the terminal due to the measurement of the neighboring cells.

[0154] If the channel QoS of the high-priority frequency cell 830 is higher than a specific threshold (e.g., a third threshold) (ThreshX-high) 865, the terminal may reselect the high-priority frequency cell 830 as a serving cell. If the channel QoS of the low-priority frequency cell 820 is higher than a specific threshold (e.g., a fourth threshold) (ThreshX-low) 860, and the QoS of the serving cell 810 is lower than a fifth threshold (e.g., ThreshServing-low) 840, the terminal may reselect the low-priority frequency cell 820 as a serving cell.

[0155] The reference signal received strength (RSRP) or reference signal received quality (RSRQ) may be considered when the terminal reselects a cell. When the received signal quality (ie, RSRQ) is used, the base station may provide Threshserving-lowQ, ThreshX-lowQ, and ThreshX-highQ to the terminal respectively by broadcasting. If the received signal strength (ie, RSRP) is used, Threshserving-lowP, ThreshX-lowP, and ThreshX-highP may be used in the present disclosure to distinguish them from the above variables.

[0156] On the other hand, 5G systems can support various numerologies. In existing LTE, frequency bandwidth is the main numerology. However, in addition, other factors such as subcarrier spacing between subcarriers, CP length, and subframe length can be considered. The specific values ​​of the above factors depend on various services, such as enhanced mobile broadband (eMBB) services for enhancing existing voice / data communications supported by 5G cells, ultra-reliable and low-latency communications (URLLC) services, and large-scale machine type communications (MTC) services for large-scale Internet of Things and requirements.

[0157] The 5G physical layer is expected to have a maximum of 2048 subcarriers. In the existing LTE, a subcarrier spacing of 15kHz is applied to support frequency bandwidths up to 20MHz. However, since 5G will support wider frequency bandwidths, the subcarrier spacing will also increase. In the 5G system, 30kHz and 60kHz are considered in addition to the existing 15kHz. In general, wide subcarrier spacing reduces the Doppler shift effect. 15kHz can be considered for Internet of Things (IoT) terminals or services using narrow bandwidths in low frequency bands and 30kHz or 60kHz for wide bandwidths and fast moving scenarios. On the other hand, it may be inefficient for one terminal to support all the various subcarrier spacings in terms of complexity and cost. The supported numerology may be limited depending on the services that the base station also supports.

[0158] In the present disclosure, a 5G base station broadcasts the numerology supported by each 5G frequency or cell. In addition, the terminal considers the numerology supported by the cell when reselecting the cell.

[0159] The base station can provide the terminal with the numerology supported by each frequency or cell using the system information.

[0160] Fig. 9 An example of a configuration supporting numerology according to an embodiment of the present disclosure is shown.

[0161] Reference Fig. 9, a cell can use system information (SIB) 910 to broadcast the numerology supported by a cell itself 920 and adjacent frequency / cells 930 and 935. A cell can support at least one numerology 940 and 945. Each numerology 940 and 945 can be composed of a combination of several elements. For example, each numerology 940 and 945 can be composed of at least one combination of system bandwidth, subcarrier spacing, CP length, subframe length, etc. Although not shown, each numerology 940 and 945 can also be composed of a combination of different elements. In order to reduce signaling overhead, each numerology 940 and 945 can be encoded with an index. For example, a frequency bandwidth of 10MHz, a subcarrier spacing of 15kHz, a CP length of 1ms, and a subframe length of 10ms can be represented by an index value of 1.

[0162] Fig.10 A process of performing cell reselection according to an embodiment of the present disclosure is shown.

[0163] In the present disclosure, the terminal may use system information to receive numerology information supported by the serving cell and the neighboring cell (frequency) from the cell. The terminal may derive a priority by considering both the numerology supported by the cell at the same or different frequencies and the numerology supported by the current serving cell to perform cell reselection using the priority information. If a specific cell having a frequency with a priority higher than the priority of the current frequency has a received signal quality better than a specific threshold, the terminal may reselect the cell with the better received signal quality. The cell may be able to support at least the numerology supported by the terminal. The terminal may derive frequency priority 1010 (1015) based on the numerology supported by each frequency (or a specific cell of each frequency). The rules for determining frequency priority may be various. For example, the base station may use system information to provide the terminal with priority information and supported numerology about each frequency.

[0164] For example, the base station may send system information including priority information corresponding to each frequency and supported numerology (e.g., consisting of subcarrier spacing information) to the terminal, as shown in the following example. At this time, a priority with a higher number may mean a higher priority. For example, "0" may represent the lowest priority: (1) Frequency: A; numerology: 60kHz; priority: 1; (2) Frequency: B; numerology: 15kHz; priority: 4; (3) Frequency: C; numerology: 15kHz, 30kHz; priority: 3; (4) Frequency: D; numerology: 30kHz; priority: 0; and (5) Frequency: E; numerology: 30kHz, 60kHz; priority: 2.

[0165] The terminal can derive a new (UE-specific) frequency priority applied to the terminal by considering the priority of each frequency and the supported numerology. At this time, the frequency that supports all numerologies supported by the terminal can have the highest priority. At this time, the frequency that supports some numerologies supported by the terminal can have the second highest priority. On the other hand, the frequency that does not support the numerologies supported by the terminal at all can have the lowest priority. At the same time, according to an embodiment, when the priority of each frequency is the same, the frequency that only supports one subcarrier spacing (or supports a smaller number of subcarrier spacings) can have a higher priority.

[0166] For example, the priority of the frequencies in the above examples can be determined based on the numerology supported by the terminal (UE supported numerology) (e.g., the subcarrier spacing supported by the terminal), as follows: (1) UE supports 15kHz, 30kHz, 60kHz: B, C, E, A, D; (2) UE supports 15kHz, 30kHz: B, C, D, E; (3) UE supports 15kHz, 60kHz: B, A, E; (4) UE supports 30kHz, 60kHz: E, A, D; and (5) UE supports 60kHz: A, E.

[0167] The terminal may perform an initial frequency selection process (1020) based on the derived frequency priority information. The terminal may select a frequency (1025) of the terminal by considering signal quality, etc. If the frequency at which the terminal currently resides is the best, the terminal may determine whether there is an appropriate cell within the frequency range (1040). If all cells of the frequency do not support the desired numerology (1050) or the signal quality is poor, the terminal may select an appropriate cell (1030) of another frequency with the next priority. If a higher priority frequency (1035) with good signal quality is found, the terminal may select the frequency (1025). If a higher priority frequency with good signal quality is not found, the terminal may perform a frequency search (1030) again. If all cells of a specific frequency support a numerology supported by the terminal, the terminal may reside on a specific cell of the frequency. If there are multiple cells on a frequency and only a specific cell supports the numerology supported by the terminal, the terminal may reside only on those cells. The terminal residing on a cell supporting the numerology supported by the terminal may proceed to step 1055 and return to step 1015.

[0168] Fig.11 The operation of the terminal according to an embodiment of the present disclosure is illustrated.

[0169] Reference Fig.11 In step 1110, the terminal may receive numerology supported by the serving cell and the neighboring cells from the serving cell. In addition, the terminal may receive priority information about each frequency and information about numerology supported by the serving cell and the neighboring cells through separate messages.

[0170] In step 1120, the terminal may derive a cell reselection priority using the received numerology and the priority information of each frequency. In step 1130, the terminal may perform cell reselection using the reselection priority information.

[0171] After that, the terminal can camp on the cell supporting the numerology supported by the UE at the reselected frequency. The received signal quality of the camped cell will meet a certain threshold. If no cell meets the threshold, the terminal can reselect the next priority frequency.

[0172] Fig.12 The configuration of a terminal according to an embodiment of the present disclosure is shown.

[0173] Reference Fig.12According to an embodiment of the present disclosure, a terminal may include a transceiver and a controller 1240. The terminal may further include a memory 1230. At this time, the transceiver may be a radio frequency (RF) processor 1210. In an embodiment, the transceiver may include an RF processor 1210 and a baseband processor 1220.

[0174] The RF processor 1210 is used to transmit / receive signals through a radio channel, such as frequency band conversion and signal amplification. That is, the RF processor 1210 can up-convert the baseband signal provided from the baseband processor 1210 into an RF band signal, and then transmit the RF band signal through an antenna, and down-convert the RF band signal received through the antenna into a baseband signal. For example, the RF processor 1210 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc. Fig.12 Only one antenna is shown, but the terminal may include multiple antennas. In addition, the RF processor 1210 may include multiple RF chains. In addition, the RF processor 1210 may perform beamforming. For beamforming, the RF processor 1210 may adjust the phase and size of each signal sent and received by multiple antennas or antenna elements. In addition, the RF processor 1210 may perform MIMO and may receive multiple layers when performing MIMO operations. The RF processor 1210 may perform receive beam scanning (sweep) by appropriately configuring multiple antennas or antenna elements under the control of the controller 1240, or adjust the direction and beam width of the receive beam so that the receive beam resonates with the transmit beam.

[0175] The baseband processor 1220 performs a conversion function between a baseband signal and a bit string according to the physical layer standard of the system. For example, when sending data, the baseband processor 1220 generates a complex symbol by encoding and modulating the transmitted bit string. In addition, when receiving data, the baseband processor 1220 can recover the received bit string by demodulating and decoding the baseband signal provided from the RF processor 1210. For example, according to the orthogonal frequency division multiplexing (OFDM) scheme, when sending data, the baseband processor 1220 can generate a complex symbol by encoding and modulating the transmitted bit string, map the complex symbol to a subcarrier, and then configure the OFDM symbol by an inverse fast Fourier transform (IFFT) operation and a cyclic prefix (CP) insertion. In addition, when receiving data, the baseband processor 1220 can segment the baseband signal provided from the RF processor 1410 in OFDM symbol units, recover the signal mapped to the subcarrier by a fast Fourier transform (FFT) operation, and then recover the bit string received by modulation and decoding.

[0176] As described above, the baseband processor 1220 and the RF processor 1210 can send and receive signals. Therefore, the baseband processor 1220 and the RF processor 1210 can be referred to as a transmitter, a receiver, a transceiver, or a communication interface. In addition, at least one of the baseband processor 1220 and the RF processor 1210 may include multiple communication modules to support a variety of different radio access technologies. In addition, at least one of the baseband processor 1220 and the RF processor 1210 may include different communication modules to process signals of different frequency bands. For example, different radio access technologies may include radio LANs (e.g., IEEE 802.11, etc.), cellular networks (e.g., LTE, etc.), etc. In addition, different frequency bands may include ultra-high frequency (SHF) (e.g., 2.5 GHz, 5 GHz, etc.) bands, millimeter wave (e.g., 60 GHz, etc.) bands.

[0177] The memory 1230 may store data, such as basic programs, applications, and configuration information for the operation of the terminal. Specifically, the storage device 1230 may store information associated with a second access node that performs wireless communication using a second access technology. The memory 1230 may provide stored data according to a request from the controller 1240. The controller 1240 may control the overall operation of the terminal to perform any one of the operations of the above-mentioned embodiments. For example, the controller 1240 may send / receive signals through the baseband processor 1220 and the RF processor 1210. In addition, the controller 1240 may record data in the memory 1230 and read data from the memory 1230. For this purpose, the controller 1240 may include a circuit, a dedicated circuit, or at least one processor. For example, the controller 1240 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls a higher layer such as an application. In addition, the operation of the terminal may be implemented by including a memory device that stores corresponding program codes in any component of the terminal. That is, the controller 1240 may perform the above-mentioned operations by reading and executing the program codes stored in the memory device by a processor, a central processing unit (CPU), etc. In addition, according to an embodiment of the present disclosure, the controller 1240 may include a multi-connection processor 1245 to perform processing to be operated in the multi-connection mode. The controller 1240 may be electrically connected to other components, for example, the transceiver 1210 .

[0178] Fig.13 The configuration of a base station according to an embodiment of the present disclosure is shown.

[0179] Reference Fig.13, the base station according to an embodiment of the present disclosure may include a transceiver and a controller 1340. In addition, the base station may further include a backhaul communication interface 1350 and a memory 1330. At this time, the transceiver may be a radio frequency (RF) processor 1310. According to an embodiment, the transceiver may include an RF processor 1310 and a baseband processor 1320.

[0180] The RF processor 1310 is used to transmit / receive signals through a radio channel, such as frequency band conversion and signal amplification. That is, the RF processor 1310 can up-convert the baseband signal provided from the baseband processor 1320 into an RF band signal, then transmit the RF band signal through an antenna, and down-convert the RF band signal received through the antenna into a baseband signal. For example, the RF processor 1310 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc. Fig.13 Only one antenna is shown, but the base station may include multiple antennas. In addition, the RF processor 1310 may include multiple RF chains. In addition, the RF processor 1310 may perform beamforming. For beamforming, the RF processor 1310 may adjust the phase and size of each signal sent and received through multiple antennas or antenna elements. The RF processor 1310 may perform downlink MIMO operations by sending one or more layers.

[0181] The baseband processor 1320 performs a conversion function between a baseband signal and a bit string according to the physical layer standard of the system. For example, when sending data, the baseband processor 1320 generates a complex symbol by encoding and modulating the transmitted bit string. In addition, when receiving data, the baseband processor 1320 can recover the received bit string by demodulating and decoding the baseband signal provided from the RF processor 1310. For example, according to the OFDM scheme, when sending data, the baseband processor 1320 can generate a complex symbol by encoding and modulating the transmitted bit string, mapping the complex symbol to a subcarrier, and then configuring the OFDM symbol through an IFFT operation and CP insertion. In addition, when receiving data, the baseband processor 1320 divides the baseband signal provided from the RF processor 1310 in OFDM symbol units, and recovers the signal mapped to the subcarrier through an FFT operation, and then recovers the received bit string through modulation and decoding.

[0182] The baseband processor 1320 and the RF processor 1310 can send and receive signals as described above. Therefore, the baseband processor 1320 and the RF processor 1310 can be referred to as a transmitter, a receiver, a transceiver, a communication interface, or a wireless communication interface. In addition, at least one of the baseband processor 1320 and the RF processor 1310 may include multiple communication modules to support a variety of different radio access technologies. In addition, at least one of the baseband processor 1320 and the RF processor 1310 may include different communication modules to process signals in different frequency bands. For example, different radio access technologies may include wireless LANs (e.g., IEEE 802.11, etc.), cellular networks (e.g., LTE, etc.), etc. In addition, different frequency bands may include ultra-high frequency (SHF) (e.g., 2.5 GHz, 5 GHz, etc.) bands, millimeter wave (e.g., 60 GHz, etc.) bands.

[0183] The backhaul communication interface 1350 provides an interface for performing communication with other nodes within the network. That is, the backhaul communication interface 1350 can convert a bit string sent from a base station to other nodes (e.g., an auxiliary base station (or other adjacent base stations), a core network, etc.) into a physical signal, and convert a physical signal received from other nodes into a bit string.

[0184] The memory 1330 may store data such as basic programs, applications, and configuration information for base station operation. Specifically, the memory 1330 may store information about bearers assigned to access terminals, measurement results reported from access terminals, etc. In addition, the memory 1330 may store information as a determination criterion for providing multiple connections to the terminal or stopping multiple connections to the terminal. The memory 1330 may provide stored data according to a request from the controller 1340.

[0185] The controller 1340 can control the overall operation of the base station to perform any one of the operations of the above-mentioned embodiments. For example, the controller 1340 can send / receive signals through the baseband processor 1320 and the RF processor 1310 or the backhaul communication interface 1350. In addition, the controller 1340 can record data in the memory 1330 and read data from the memory 1330. For this purpose, the controller 1340 may include a circuit, a dedicated circuit, or at least one processor. For example, the controller 1340 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls a higher layer such as an application. In addition, the operation of the base station can be implemented by including a memory device storing corresponding program codes in any component of the terminal. That is, the controller 1340 can perform the above-mentioned operations by reading and executing the program codes stored in the memory device by a processor, a central processing unit (CPU), etc. In addition, according to an embodiment of the present disclosure, the controller 1340 may include a multi-connection processor 1345 to perform processing to be operated in a multi-connection mode. The controller 1340 may be electrically connected to other components, for example, a transceiver 1310.

[0186] Hereinafter, the operating principle of the present disclosure will be described in detail with reference to the accompanying drawings. Hereinafter, when it is determined that the detailed description of the known technology related to the present disclosure may obscure the subject matter of the present disclosure, its detailed description will be omitted. In addition, the following terms are defined in consideration of the functions in the present disclosure, and these terms may be interpreted in different ways by the intention or practice of the user and operator. Therefore, their definitions should be interpreted based on the contents in the entire specification.

[0187] For convenience of explanation, terms indicating access nodes, terms indicating network entities, terms indicating messages, terms indicating interfaces between network entities, terms indicating various types of identification information, etc. used in the following description are exemplified. Therefore, the present disclosure is not limited to the terms to be described below, and other terms indicating objects having equivalent technical meanings may be used.

[0188] Hereinafter, for convenience of explanation, the present disclosure uses terms and names defined in 3rd Generation Partnership Project Long Term Evolution (3GPP LTE). However, the present disclosure is not limited to the terms and names, but may also be equally applied to systems according to other standards.

[0189] Fig.14 An example of a network structure of an LTE system according to an embodiment of the present disclosure is shown.

[0190] Reference Fig.14, a wireless communication system (e.g., an LTE system) may include a plurality of base stations (evolved Node Bs (eNBs)) 1420, 1423, 1425, and 1427, a mobility management entity (MME) 1430, and a serving gateway (S-GW) 1440. A user equipment (UE) (or terminal) 1410 is connected to an external network through the base stations 1420, 1423, 1425, and 1427 and the S-GW 1440.

[0191] Base stations 1420, 1423, 1425, and 1427 are access nodes of a cellular network and provide wireless access to a terminal 1410 connected to the network. That is, in order to serve the user's business, the base stations 1420, 1423, 1425, and 1427 collect and schedule state information such as a buffer state, an available transmission power state, and a channel state of the terminal 1410 to support a connection between the terminal 1410 and a core network (CN). The MME 1430 is a device for performing various control functions of the terminal 1410 and a mobility management function, and is connected to a plurality of base stations 1420, 1423, 1425, and 1427. In addition, the S-GW 1440 is a device for providing data bearers. In addition, MME 1430 and S-GW 1440 can also perform authentication, bearer management, etc. for the terminal 1410 connected to the network, and process packets arriving from base stations 1420, 1423, 1425 and 1427 and packets to be sent to base stations 1420, 1423, 1425 and 1427.

[0192] Fig.15 A radio protocol structure in an LTE system according to an embodiment of the present disclosure is shown.

[0193] Reference Fig.15According to the radio protocol of the LTE system, the terminal and the base station (eNB) include packet data convergence protocol (PDCP) 1510 and 1530, radio link control (RLC) 1515 and 1535, and medium access control (MMC) 1520 and 1540, respectively. The packet data convergence protocol (PDCP) 1510 and 1530 performs operations such as IP header compression / recovery, and the radio link control 1515 and 1535 reconfigures the PDCP packet data unit (PDU) to an appropriate size. The MAC 1520 and 1540 are connected to several RLC layer devices configured in one terminal, and perform operations of multiplexing RLC PDUs in MAC PDUs and demultiplexing RLC PDUs from MAC PDUs. The physical layer (PHY) 1525 and 1545 perform operations of channel coding and modulating high-layer data, making the high-layer data into OFDM symbols, and sending the high-layer data to the radio channel, or demodulating the OFDM symbols received through the radio channel, channel decoding the OFDM symbols, and sending the OFDM symbols to the high layer. In addition, even the physical layers 1525 and 1545 use hybrid automatic repeat request (HARQ) for additional error correction, and can send whether the receiving end receives the packet sent from the transmitting end with 1 bit. This is called HARQ ACK / NACK information. Downlink HARQ ACK / NACK information about uplink transmission can be sent through the physical channel of the physical hybrid ARQ indicator channel (PHICH), and uplink HARQ ACK / NACK information about downlink transmission can be sent through the physical channel of the physical uplink control channel (PUCCH) or the physical uplink shared channel (PUSCH).

[0194] Although not shown in the drawing, a radio resource control (RRC) layer exists at a higher part of the PDCP layers 1510 and 1530 of the terminal and the base station, and the RRC layer may receive and send connection and measurement-related control messages for radio resource control.

[0195] Fig.16 A detailed example of a network structure of a wireless communication system according to an embodiment of the present disclosure is shown.

[0196] Reference Fig.16 , a radio access network (RAN) of an LTE mobile communication system may include a base station 1420, an MME 1430, and an S-GW 1440. A user equipment 1410 may access an external network through the base station 1420, the S-GW 1440, and a packet data network (PDN) gateway (P-GW) 1470.

[0197] The base station 1420 is a RAN node and corresponds to the radio network controller (RNC) of the universal terrestrial radio access network (UTRAN) system and the base station controller (BSC) of the GSM edge radio access network (GERAN) system. The base station 1420 is connected to the terminal 1410 through a radio channel and is used for wireless communication similar to the RNC / BSC management of the terminal 1410, and several cells can be used simultaneously. In LTE, since all user services are provided through a shared channel, a device for collecting and scheduling the situation information of the terminal 1410 is required, which is processed by the base station 1420.

[0198] The MME 1430 is a device for being responsible for various control functions, wherein one MME may be connected to a plurality of base stations. The MME 1430 may be connected to a serving GPRS support node (SGSN) 1450 via an S3 interface, and may be connected to a home subscriber server (HSS) 1460 via an S6a interface. The S-GW 1440 is a device for providing data bearers and generating or removing bearers under the control of the MME 1430. The application function (AF) 1490 is a device for exchanging application-related information with a user at an application level. For example, an enhanced proxy call session control function (eP-CSCF) as an IMS network device is a type of AF.

[0199] The policy charging and rules function (PCRF) 1480 is a device that controls policies related to quality of service (QoS). The policy is defined by a policy and charging control (PCC) rule, and the PCC rule is sent and applied to the P-GW 1470. In order to apply the PCC rule, the P-GW 1470 may include a policy and charging rules enforcement function (PCEF).

[0200] In general, a user plane (UP) refers to a path connected between a terminal 1410 that transmits and receives user data and a base station 1420 that is a RAN node, a path connected between the base station 1420 that is a RAN node and an S-GW 1440, and a path connected between the S-GW 1440 and the P-GW 1470. Among these paths, the portion of the radio channel that uses a severe resource restriction is the path between the terminal 1410 and the base station 1420 that is a RAN node. In a wireless communication system such as LTE, QoS can be applied in units of an evolved packet system (EPS) bearer. One EPS bearer can be used to transmit IP flows with the same QoS requirements. Parameters associated with QoS can be specified in the EPS bearer. Examples of parameters may include a QoS class identifier (QCI) and an allocation and retention priority (ARP). The QCI is a parameter that defines the QoS priority, and the ARP is a parameter used to determine whether to allow or deny the generation of a new EPS bearer.

[0201] The EPS bearer corresponds to a packet data protocol context (PDP context) of a general packet radio service (GPRS) system. One EPS bearer may belong to a PDN connection, and the PDN connection may have an access point name (APN) as an attribute. If a PDN connection for an IMS service is generated, the PDN connection may be generated using a well-known IMS APN. If the terminal 1410 accesses the communication network through a web application of a web browser, a PDN connection for access may be generated through an APN for Internet services or through an IMS APN.

[0202] Fig.17a and 17b A method for establishing bearer-based QoS in a wireless communication system according to an embodiment of the present disclosure is shown.

[0203] Reference Fig.17a and Fig.17b , an operator providing LTE services may be able to provide services requiring different quality of service (QoS) to subscribers with different service levels. For this purpose, the operator may know the service level and service type of the subscriber and be able to differentially allocate and manage radio resources 1750 for user IP traffic (IP flows). Therefore, the network sets the user traffic transmission path or controls the IP flow 1750 for each service according to the QoS requirements.

[0204] In the Evolved Packet System (EPS), a user traffic transmission path generates another EPS bearer according to QoS to the EPS bearer 1710. IP flows with the same QoS are mapped to a service data flow (SDF) 1730, and the SDF 1730 becomes a unit for applying QoS rules reflecting an operator policy.

[0205] Fig.17a and Fig.17b A specific relationship between the EPS bearer 1710 and the SDF 1730 is shown. In the EPS transport network, the SDF 1730 provides QoS corresponding to the service to the IP flow 1750 sent from the PDN 1790, and the EPS bearer 1710 provides QoS between the terminal 1410 and the P-GW 1470. When the SDF 1730 is sent to the user terminal 1410 through the EPS, the SDF 1730 is sent after being mapped to the EPS bearers 1710, 1720, and 1725 that can provide appropriate QoS according to the QoS rules installed in the P-GW 1470. The IP flow 1750 has different QoS characteristics depending on what service (or application) is used. The SDF 1730 filters (classifies) the IP flow of the user traffic for each service or a group of IP flows, and applies a specific QoS policy according to the subscriber class of the terminal 1410 and the application to be used. In Fig.17a and Fig.17b , the IP flow 1750 from the PDN 1790 to the user terminal 1410 is filtered to the SDF 1730 through the SDF template (classifier) ​​1740 of the P-GW 1470 according to the service characteristics, and the QoS policy (e.g., bandwidth control) is applied to each SDF to be sent to the user. For example, the first IP flow can be classified as the first SDF, so the first QoS policy can be applied, and the second IP flow can be classified as the second SDF, so the second QoS policy can be applied. The third IP flow and the fourth IP flow are classified as the third SDF, so the third QoS policy can be applied, and the fifth IP flow is classified as the fourth SDF, so the fourth QoS policy can be applied. Since the QoS in the EPS transport network is provided by the EPS bearers 1710, 1720 and 1725, each SDF 1730 is mapped and sent to the EPS bearers 1710, 1720 and 1725 that can meet the QoS requirements of each SDF itself.

[0206] An EPS bearer 1710 includes a default bearer 1725 and a dedicated bearer 1720. If the terminal 1410 accesses the LTE network, the terminal 1410 is allocated an IP address and a default data bearer 1725 is generated, and a packet data network (PDN) connection (EPS session) 1760 is generated. If the user terminal 1410 uses a service (e.g., video on demand (VOD)) that may not properly receive QoS from the default bearer 1725 during use of the service (e.g., the Internet) through the default bearer 1725, a dedicated bearer 1720 may be generated on demand (upon request). That is, the dedicated bearer 1720 is set to a different QoS from established bearers (e.g., the default bearer 1725 and other dedicated bearers).

[0207] The terminal 1410 may access several access point names (APNs) (P-GW) 1470, and a default EPS bearer 1725 and a plurality of dedicated EPS bearers 1720 may be established for each APN. The default bearer 1725 is generated when the terminal 1410 initially accesses the network, and the default bearer 1725 continues to be maintained even if the terminal 1410 does not use the service on the way, and then disappears when the terminal 1410 leaves the network. When the terminal 1410 initially accesses the network, a default bearer 1725 is generated for each APN, and whether the default bearer 1725 is generated by providing what QoS is applied to which APN as user subscription information to the HSS 1460. If the terminal 1410 initially accesses the network, the MME 1430 may download user subscription information (e.g., default APN, QoS profile of EPS subscription) from the HSS 1460, and may generate the default bearer 1725 to the corresponding PDN 1790 using the subscriber QoS profile.

[0208] exist Fig.17a and Fig.17b In the embodiment, when a downlink IP flow is sent to a user terminal 1410 via EPS, a downlink IP flow 1750 is sent through EPS bearers 1710, 1720, and 1725 and SDF 1730. The user IP flow 1750 arriving at the P-GW 1470 via the PDN 1790 is filtered into the SDF 1730 via the SDF template 1740. For example, the first IP flow (IP flow 1) is classified into the first SDF (SDF 1), the second IP flow (IP flow 2) is classified into the second SDF (SDF 2), the third IP flow (IP flow 3) and the fourth IP flow (IP flow 4) are classified into the third SDF (SDF 3), and the fifth IP flow (IP flow 5) is classified into the fourth SDF (SDF 4), so that QoS rules can be applied to each SDF and then mapped to the EPS bearers 1710, 1720, and 1725 according to the service flow template (TFT) filtering rules (1730). For example, SDF 1 and SDF 2 are mapped to the default bearer 1725, and SDF 3 and SDF 4 are mapped to the dedicated bearer 1720 and transmitted to the terminal 1410 through the corresponding EPS bearers 1720 and 1725. The flows arriving at the terminal 1410 are transmitted to the corresponding applications.

[0209] In an LTE network, QoS parameters are defined based on bearers 1710, 1720, and 1725. EPS bearer QoS parameters are bearer level QoS parameters. The bearer level is also called the SDF aggregation level. SDF aggregation refers to a collection of SDFs with the same QoS class identifier (QCI) and allocation and reservation priority (ARP) value belonging to the same EPS session. QCI and ARP are basic QoS parameters applied to all EPS bearers. QCI is a standardized different QoS characteristic represented by an integer value (e.g., 1 to 9). The standardized QoS characteristics are represented by resource type, priority, packet delay budget, and packet error loss rate.

[0210] According to the QCI resource type, EPS bearers 1710, 1720, and 1725 are divided into guaranteed bit rate (GBR) type bearers and non-GBR type bearers. The default bearer 1725 is always a non-GBR type bearer, and the dedicated bearer 1720 can be set to a GBR type bearer and a non-GBR type bearer. The GBR type bearer has QCI, ARP, GBR (UL / DL), and maximum bit rate (MBR) (UL / DL) as QoS parameters for the GBR type bearer, and the non-GBR type bearer has QCI, ARP, aggregated maximum bit rate (APN-AMBR) (UL / DL) and UE-AMBR (UL / DL). In addition to QCI and ARP, the GBR type bearer has GBR and MBR as QoS parameters, which means that fixed resources (bandwidth guarantee) are allocated to each bearer. On the other hand, the non-GBR type bearer has an aggregated maximum bit rate (AMBR) as a QoS parameter, which means that resources are not allocated to each bearer but are allocated the maximum bandwidth that can be used with other non-GBR type bearers. APN-AMBR is the maximum bandwidth that non-GBR type bearers can share within the same PDN, and UE-AMBR is the maximum bandwidth that can be shared within the same terminal. If terminal 1410 has multiple PDN connections, the sum of APN-AMBRs for each PDN may not exceed UE-AMBR.

[0211] like Fig.17a and Fig.17b As shown, if the method for establishing bearer-based QoS is applied in a wireless communication system, a group of multiple IP flows 1750 is processed with the same QoS in the network. Therefore, more precise QoS control is not possible in the EPC stages 1440 and 1470 and the E-UTRAN stages 1410 and 1420.

[0212] Therefore, according to the present disclosure, a method for establishing flow-based QoS will be described instead of Fig.17a and Fig.17b The method for establishing bearer-based QoS is shown. In the present disclosure, flows may refer to IP flows 1750 and service data flows (SDFs) 1730. SDFs may be represented by IP flow groups.

[0213] Fig.18 A method for establishing flow-based QoS in a next-generation wireless communication system according to an embodiment of the present disclosure is shown.

[0214] As mentioned above, a flow can refer to an IP flow and can refer to an SDF. An SDF can be represented by an IP flow group.

[0215] Reference Fig.18,In E-UTRAN, there are concepts of bearers 1830, 1833 and 1835, such as Fig.17a and Fig.17b As shown, however, in the next generation core network (NGCN) 1803 and 1804, the concept of bearer 1850 may or may not exist. NGCN 1803 and 1804 may be an evolved CN or a new CN of EPC 1440 and 1470 of the LTE system. NGCN may include P-GW 1804 and S-GW 1803. Optionally, NGCN may include a user plane function (UPF), a session management function (SMF) (control plane function (CPF)), etc.

[0216] If downlink data is generated in PDN 1805, IP flow 1810 is sent to base station (rNB or gNB) 1802 through PDN 1805, P-GW (0804) and S-GW 1803. At this time, base station (rNB or gNB) 1802 can be an evolved base station or a new base station of an LTE base station for a next-generation wireless communication system.

[0217] At the same time, the packets of flow 1810 may be subjected to packet marking indicating QoS information. Optionally, each flow may be mapped to specific QoS information. QoS refers to the ability or measure to ensure a specific performance level in data transmission by assigning priorities to applications, users, or data flows. QoS may indicate minimum transmission bit rate, delay, packet loss rate, etc.

[0218] The base station 1802 receiving the stream 1810 can interpret the packet tag in the packet of the stream 1810 to obtain the QoS information. Optionally, the QoS information of each stream 1810 can also be obtained based on the mapping information about the predefined stream 1810 and the QoS information. The base station 1802 can allocate the stream 1810 to the corresponding bearer of the base station through a layer or device called a packet tag / QoS mapper (PMQM) 1820 according to the QoS information. If there is no bearer corresponding to the QoS of the stream 1810, the base station 1802 can newly establish a bearer corresponding to the QoS with the terminal 1801.

[0219] For example, the first downlink data stream may be mapped to the first QoS to be assigned to the default bearer 1830, and the second downlink data stream and the third downlink data stream may be mapped to the second QoS to be assigned to the first dedicated bearer 1833. Optionally, according to an embodiment, the first dedicated bearer 1833 may correspond to the second QoS and the third QoS, so that the second downlink data stream and the third downlink data stream may be mapped to the second QoS and the third QoS to be assigned to the first dedicated bearer 1833 corresponding to each thereof. The fourth downlink data stream and the fifth downlink data stream may be mapped to the fourth QoS to be assigned to the second dedicated bearer 1835. Optionally, according to an embodiment, the second dedicated bearer 1835 may correspond to the fourth QoS and the fifth QoS, so that the fourth downlink data stream and the fifth downlink data stream may be mapped to the fourth QoS and the fifth QoS to be assigned to the second dedicated bearer 1835 corresponding to each thereof.

[0220] exist Fig.18In the example, if uplink data is generated, the terminal 1801 can confirm whether a downlink flow corresponding to the uplink data has been previously received. The confirmation process can be performed using the header information of the IP packet such as the source IP address and the destination IP address. If there is a flow corresponding to the uplink data in the previously received downlink flow, the terminal 1801 can map the uplink data to the corresponding flow and send the uplink data to the base station 1802 through the corresponding bearer. If there is no flow corresponding to the uplink data in the previously received downlink flow, the terminal 1801 can mark the QoS information to the uplink data packet through a layer or device called a packet marker / QoS mapper (PMQM) 1840. QoS refers to the ability or measure to ensure a specific performance level of data transmission by assigning priorities to applications, users or data flows. QoS can represent the minimum transmission bit rate, delay, packet loss rate, etc. The PMQM layer or device 1840 of the terminal 1801 can confirm whether there is an appropriate bearer for the marked QoS information in the currently established bearers 1830, 1833 and 1835 based on the marked QoS information. If there is an appropriate bearer, the terminal 1801 can map the uplink flow through the bearer and send the uplink flow to the base station 1802. If there is no appropriate bearer, the PMQM layer or device 1840 of the terminal 1801 can send the uplink flow while mapping the uplink flow to the default bearer 1830. The PMQM layer or device 1820 of the base station 1802 that receives the uplink flow of the default bearer 1830 can confirm the packet marking of the uplink flow to find out the QoS information. If the PMQM layer or device 1820 of the base station 1802 determines that the QoS of the uplink flow is not suitable for the QoS of the default bearer 1830, the PMQM layer or device 1820 of the base station 1802 can establish a new bearer suitable for the QoS of the uplink flow with the terminal 1801. If a new bearer is established, the terminal 1801 may transmit an uplink stream generated later to the base station 1802 through the newly established bearer instead of the default bearer 1830 .

[0221] Fig.19 A signaling process of allocating a QoS policy including QoS mapping information to each flow or allocating information on packet marking to a base station and a terminal in a method for establishing flow-based QoS according to an embodiment of the present disclosure is shown.

[0222] At this time, the flow can refer to the IP flow and can refer to the SDF. The SDF can be represented by the IP flow group.

[0223] Reference Fig.19In step 1960, the terminal 1910 may establish a user session to establish a connection with the network. The user session may include information related to the user session establishment regardless of the QoS of each service flow. Multiple flows multiplexed in the user session may be distinguished by QoS by marking packets related to QoS in each packet.

[0224] In step 1960, the terminal 1910 may receive a predetermined flow priority indicator (FPI). The flow priority indicator may be used to initialize an uplink packet without the terminal 1910 transmitting / receiving control signaling with the network. That is, the terminal 1910 may perform packet marking on the uplink packet generated from the terminal 1910 using the flow priority indicator.

[0225] In steps 1963, 1965, and 1967, the control plane (CP) function 1940 may receive a QoS request (AF QoS Request, UP QoS Request) from at least one of the application function (AF) 1950, the user plane (UP) function 1930, or the terminal 1910, respectively. The AF 1950 may provide a packet flow requiring a specific QoS. Upon receiving a new flow with a specific QoS, the UP 1930 may send a QoS request to the CP 1940 in order to process the new flow.

[0226] After receiving the QoS request message in steps 1963, 1965, and 1967, the CP 1940 may determine the authorized QoS policy according to the operator's requirements. The QoS policy may be a parameter list to be applied to the core networks (CN) 1930 and 1940, the access network (AN) 1920, and the terminal 1910 to process the flow according to the QoS. The parameter may include at least one of a DL flow descriptor, a flow priority indicator, a downlink maximum flow bit rate, a downlink session bit rate, and a reflection QoS indicator. The downlink flow descriptor may be used to distinguish flows and confirm whether to perform packet marking using the flow priority indicator received in the QoS policy. The UP 1930 may adjust the flow and maximum bit rate of the user session based on the downlink flow maximum bit rate and the downlink session bit rate. The flow priority indicator refers to a parameter set in a node of the access network (AN) 1920 and indicates how to process packets. The reflection QoS indicator indicates whether the terminal 1910 applies reflection QoS to the uplink flow corresponding to the downlink flow. The flow priority indicator and the reflective QoS indicator may be used to mark downlink user data packets.

[0227] In step 1969, CP 1930 may distribute the authorized QoS policy as described above to UP 1930 (CN QoS policy establishment).

[0228] In step 1970, CP 1930 may send a message including a QoS policy authorized by AN 1920 (AN QoS policy establishment). The QoS policy may be a list of parameters to be applied to AN 1920 and terminal 1910 to process flows according to QoS. The parameters may include at least one of a UL flow descriptor, a flow priority indicator, a flow priority, a UL maximum flow bit rate, a UL and DL guaranteed flow bit rate, a UL session bit rate, etc. The UL flow descriptor may be used to distinguish flows and confirm whether to perform packet marking using the flow priority indicator received in the QoS policy. AN 1920 may adjust the flow and maximum bit rate of the user session based on the DL flow maximum bit rate and the DL session bit rate.

[0229] In step 1973, the terminal 1910 may receive the authorized QoS policy as non-access stratum (NAS) information (UE QoS request / UE QoS policy establishment) from the CP 1930. Optionally, in steps 1975 and / or 1977, the terminal 1910 may receive the QoS policy authorized as access stratum (AS) information (QoS request to UE) from the AN 1920. The QoS policy may be a list of parameters to be applied to the terminal 1910 to process the flow according to the QoS. The parameter may include at least one of a UL flow descriptor, a flow priority indicator, a UL guaranteed flow bit rate, etc. In steps 1975 and 1977, the access network (AN) 1920 may assign the QoS policy of the terminal 1910 to the terminal 1910. At this time, in step 1975, the flow-based QoS policy may be assigned to the terminal 1910 according to the network interface. Optionally, in step 1977, the bearer-based QoS policy may also be assigned to the terminal 1910. If AN 1920 processes QoS by considering both flows and bearers, both flow-based QoS policies and bearer-based QoS policies may be allocated to terminal 1910 (1975 and 1977). If AN 1920 processes QoS by considering only flows, only flow-based QoS policies may be allocated to terminal 1910 (1975). If AN 1920 processes QoS by considering only bearers, only bearer-based QoS policies may be allocated to terminal 1910 (1977). If AN 1920 and CN 1930 normally receive the authorized QoS policies and complete the establishment, in steps 1980 and 1983, AN 1920 and UP 1930 may send responses (AN QoS Session Ack and CN QoS Session ACK) to CP 1940.

[0230] Fig. 20 The process of configuring a bearer and sending downlink data in a method for establishing flow-based QoS according to an embodiment of the present disclosure is shown.

[0231] At this time, the flow can refer to the IP flow and can refer to the SDF. The SDF can be represented by the IP flow group.

[0232] Reference Fig. 20 , the base station (rNB, gNB) 2020 and the terminal 2010 can receive the Fig.19 The QoS policy for authorization is established by the process. The base station (rNB or gNB) 2020 can be an evolved base station or a new base station of an LTE base station for a next-generation wireless communication system.

[0233] In step 2040, the base station 2020 may receive a QoS policy establishment authorized from a next generation core network (NGCN) 2030. The NGCN 2030 may be an evolved CN or a new CN of the EPC of the LTE system. The NGCN may include a P-GW and an S-GW. Optionally, the NGCN may include a user plane function (UPF), a session management function (SMF) (control plane function (CPF)), etc. The QoS policy may include mapping information about each flow and the QoS corresponding thereto, and may include information related to a packet marking for indicating the QoS of the flow. In step 2043, the base station 2020 that receives the QoS policy in step 2040 may confirm the flow and QoS mapping information, packet marking information, etc.

[0234] The terminal 2010 may request the QoS policy authorized in step 2045 from the base station 2020 at the AS level to receive the authorized QoS policy establishment from the base station 2020. Optionally, in step 2047, the terminal 2010 may request the NGCN 2030 for the authorized QoS policy at the NAS level, thereby receiving the authorized QoS policy establishment from the NGCN 2030. The QoS policy may include mapping information about each flow and the QoS corresponding thereto, and may include information related to the packet marking for indicating the QoS of the flow. In addition, the QoS policy may include QoS information for each bearer. The terminal 2010 that has received the QoS policy in step 2045 or 2047 may confirm the flow and QoS mapping information, the packet marking information, the QoS information for each bearer, etc. in step 2049.

[0235] As described above, if the initial QoS establishment process is completed, then in step 2050, the NGCN 2030 may send a downlink packet to the base station.

[0236] The base station 2020 may confirm the flow and QoS mapping information about the packet in step 2053, or confirm the marking of the packet to confirm the QoS based on the QoS policy established in step 2040. In step 2055, the base station 2010 may confirm whether there is a bearer satisfying the QoS of the downlink flow among the bearers currently established between the base station 2020 and the terminal 2010 (e.g., data radio bearers (DRBs)).

[0237] If there is a bearer satisfying the QoS of the downlink flow in the current bearer, the base station 2020 may send the downlink packet to the terminal 2010 through the bearer in step 2057. Meanwhile, the bearer established between the terminal 2010 and the base station 2020 may be established when the RRC connection between the terminal 2010 and the base station 2020 is established / reconfigured, and multiple bearers may also be established. According to an embodiment, when establishing a bearer, the base station 2020 may include an indicator indicating which bearer is a default bearer to indicate the default bearer to the terminal 2010.

[0238] If there is no bearer satisfying the QoS of the downlink flow in the current bearer, then in step 2059, the base station 2020 may set a new bearer capable of satisfying the QoS of the downlink flow with the terminal 2010. In step 2060, the base station 2020 may send a downlink packet to the MS 2010 through the bearer newly established in step 2059.

[0239] Fig.21 The process of establishing a bearer and sending downlink data by a terminal in a method for establishing flow-based QoS according to an embodiment of the present disclosure is shown.

[0240] At this time, the flow can refer to the IP flow and can refer to the SDF. The SDF can be represented by the IP flow group.

[0241] Reference Fig.21 , the base station (rNB, gNB) 2120 and the terminal 2110 can receive the Fig.19 The process is authorized to establish a QoS policy. The base station (rNB or gNB) 2120 can be an evolved base station or a new base station of an LTE base station for a next-generation wireless communication system.

[0242] In step 2140, the base station 2120 may receive a QoS policy establishment authorized from the NGCN 2130. The NGCN 2130 may be an evolved CN or a new CN of the EPC of the LTE system. The NGCN may include a P-GW and an S-GW. Optionally, the NGCN may include a user plane function (UPF), a session management function (SMF) (control plane function (CPF)), etc. The QoS policy may include mapping information about each flow and the QoS corresponding thereto, and may include information related to a packet marking for indicating the QoS of the flow. In step 2043, the base station 2120 that receives the QoS policy in step 2140 may confirm the flow and QoS mapping information, the packet marking information, etc.

[0243] The terminal 2110 may request the QoS policy authorized in step 2145 from the base station 2120 at the AS level to receive the authorized QoS policy establishment from the base station 2120. Optionally, in step 2147, the terminal 2110 may request the authorized QoS policy from the NGCN 2110 at the NAS level, thereby receiving the authorized QoS policy establishment from the NGCN 2130. The QoS policy may include mapping information about each flow and the QoS corresponding thereto, and may include information related to the packet marking for indicating the QoS of the flow. In addition, the QoS policy may include QoS information for each bearer. The terminal 2110 that has received the QoS policy in step 2145 or 2147 may confirm the flow and QoS mapping information, the packet marking information, the QoS information for each bearer, etc. in step 2149.

[0244] In step 2150, if an uplink packet is generated from the terminal 2110, the terminal 2110 may confirm and use the flow and QoS mapping information about the packet in step 2153 based on the QoS policy established in step 2145 or step 2147, or may indicate the QoS of the uplink flow or packet to the base station 2120 by marking the packet with the QoS corresponding to the packet. In step 2155, the terminal 2110 may confirm whether there is a bearer satisfying the QoS of the uplink flow in the bearer currently established between the base station 2120 and the terminal 2110 (e.g., a data radio bearer (DRB)).

[0245] If there is a bearer satisfying the QoS of the uplink flow in the current bearer, the terminal 2110 may transmit the uplink packet to the terminal 2010 through the bearer in step 2157. If there is a bearer satisfying the QoS of the uplink flow, the QoS of the uplink flow may be represented and mapped by the QoS of the bearer. In this case, the packet marking in step 2153 may be skipped. Alternatively, if a downlink flow corresponding to the flow of the uplink packet has been received before step 2153, the terminal 2110 may skip the packet marking in step 2153. However, if it is determined to be necessary, the terminal 2110 may perform the packet marking in step 2153.

[0246] In step 2157, the base station 2120 receiving the uplink packet may confirm the QoS mapping information or packet marking of the flow in step 2159. However, for some reason (for example, not the default bearer), the base station 2120 may skip the QoS mapping information or packet marking check of the flow. Meanwhile, the bearer established between the terminal 2110 and the base station 2120 may be established when the RRC connection between the terminal 2110 and the base station 2120 is established / reconfigured, and several bearers may also be established. According to an embodiment, when establishing a bearer, the base station 2120 may include an indicator indicating which bearer is the default bearer to indicate the default bearer to the terminal 2110.

[0247] If there is no bearer in the current bearer that satisfies the QoS of the uplink flow, in step 2153, the terminal 2110 may use a packet tag indicating the QoS corresponding to the packet of the uplink flow, or indicate QoS mapping information about the uplink flow to the base station 2120, and in step 2160, send the uplink packet to the base station 2120 through the default bearer previously established during RRC connection establishment / reconfiguration.

[0248] In step 2163, the base station 2120 checks the QoS mapping information or packet marking of the flow of the uplink packet received through the default bearer, and then if the base station 2120 determines that the QoS of the uplink packet matches the default bearer, the uplink packet can be sent to the NGCN 2130.

[0249] However, if it is determined in step 2163 that the base station 2120 checks the QoS mapping information or packet marking of the flow of the uplink packet and then the default bearer does not match the QoS of the uplink packet, the base station 2120 may establish a new bearer suitable for the QoS of the uplink packet in step 2165. In step 2167, the terminal 2110 may send a packet corresponding to the uplink flow to the base station 2120 through the newly established bearer.

[0250] Fig. 22An example of the operation of a base station in a method for establishing flow-based QoS according to an embodiment of the present disclosure is shown.

[0251] At this time, the flow can refer to the IP flow and can refer to the SDF. The SDF can be represented by the IP flow group.

[0252] Reference Fig. 22 , the base station can Fig.19 The process in receives the authorized QoS policy establishment. The base station may be an evolved base station or a new base station of an LTE base station for a next generation wireless communication system. The base station may receive the QoS policy establishment authorized from the NGCN. The NGCN may be an evolved CN or a new CN of the EPC of the LTE system. The QoS policy may include mapping information about each flow and the QoS corresponding thereto, and may include information related to a packet marking for indicating the QoS of the flow.

[0253] If the base station receives a packet of the flow, the base station may separately process the uplink packet and the downlink packet in step 2210. That is, the base station 2210 may confirm whether the packet of the flow is a downlink packet or an uplink packet.

[0254] If the base station receives a downlink packet from the NGCN, the base station confirms the marking information or QoS mapping information about the downlink packet based on the established QoS policy to confirm the QoS of the flow of the downlink packet in step 2220. In step 2230, the base station may confirm whether there is a bearer satisfying the downlink QoS in the bearer currently established between the base station and the terminal (e.g., a data radio bearer (DRB)).

[0255] If there is a bearer that satisfies the QoS of the downlink flow in the current bearer, the base station may send the downlink packet to the terminal through the bearer in step 2250. The bearer established between the terminal and the base station may be established when the RRC connection between the terminal and the base station is established / reconfigured, and several bearers may be established. According to an embodiment, when establishing a bearer, the base station may include an indicator indicating which bearer is a default bearer to indicate the default bearer to the terminal.

[0256] If there is no bearer that satisfies the QoS of the downlink flow in the current bearer, the base station may establish a new bearer that can satisfy the QoS of the downlink flow with the terminal in step 2240. In step 2250, the base station may send a downlink packet to the terminal through the newly established bearer.

[0257] Meanwhile, if the base station receives an uplink packet from the terminal, then in step 2220, the base station confirms the marking information of the packet or confirms the flow and QoS mapping information based on the establishment of a QoS policy to confirm the QoS of the flow of the uplink packet. In step 2270, it is confirmed whether the QoS of the uplink flow matches the QoS of the bearer corresponding to the uplink flow. According to an embodiment, the process of confirming whether the QoS of the uplink flow in step 2270 matches the corresponding QoS of the bearer can be performed only for the uplink flow received by the base station through the default bearer. That is, in the case of a bearer other than the default bearer, the base station can skip the process of confirming whether the QoS of the uplink flow matches the QoS of the corresponding bearer for a predetermined reason (e.g., a reduction in complexity).

[0258] If it is determined in step 2260 that the QoS of the uplink flow received by the base station in step 2210 matches the QoS of the corresponding bearer, then in step 2290, the base station may send the uplink packet to the NGCN.

[0259] However, if it is determined in step 2260 that the QoS of the uplink received by the base station in step 2210 does not match the QoS of the corresponding bearer, the base station may establish a new bearer suitable for the uplink QoS with the terminal in step 2280. In step 2290, the base station may send the uplink packet to the NGCN. Thereafter, the base station may receive a packet corresponding to the uplink flow from the terminal through the newly established bearer.

[0260] Fig.23 An example of an operation of a terminal in a method for establishing flow-based QoS according to an embodiment of the present disclosure is shown.

[0261] At this time, the flow can refer to the IP flow and can refer to the SDF. The SDF can be represented by the IP flow group.

[0262] Reference Fig.23 , the terminal can be based on Fig.19 The terminal may receive the authorized QoS policy establishment by requesting the authorized QoS policy from the base station at the AS level, or may receive the authorized QoS policy establishment by requesting the authorized QoS policy from the NGCN at the NAS level. The QoS policy may include mapping information about each flow and the QoS corresponding thereto, and may include information related to the packet marking used to indicate the QoS of the flow. In addition, the QoS policy may include QoS information for each bearer.

[0263] If the terminal generates a flow of uplink packets, then in step 2310, the terminal confirms and uses the flow and QoS mapping information about the packet based on the established QoS policy, or marks the QoS corresponding to the packet to indicate the uplink flow or QoS of the packet to the base station. In step 2320, the terminal can confirm whether there is a bearer that satisfies the QoS of the uplink flow in the bearer (e.g., data radio bearer (DRB)) currently established between the base station and the terminal.

[0264] If there is a bearer satisfying the QoS of the uplink flow among the current bearers, the terminal may send the uplink packet to the base station through the bearer in step 2230. If there is a bearer satisfying the QoS of the uplink flow, the QoS of the uplink flow may be represented and mapped by the QoS of the bearer, so that the terminal may skip packet marking in step 2310. Alternatively, if a downlink flow corresponding to the flow of the uplink packet has been received before step 2310, the terminal 2310 may skip packet marking in step 2310. However, if it is determined to be necessary, the terminal may perform packet marking in step 2310.

[0265] If there is no bearer in the current bearer that satisfies the QoS of the uplink flow, in step 2340, the terminal 2340 may use a packet tag indicating the QoS corresponding to the packet of the uplink flow, or indicate QoS mapping information about the uplink flow to the base station, and send the uplink packet to the base station 2120 via the default bearer previously established during RRC connection establishment / reconfiguration in step 2340.

[0266] At the same time, the bearer established between the terminal and the base station can be established when the RRC connection between the terminal and the base station is established / reconfigured, and several bearers can be established. According to an embodiment, when establishing a bearer, the base station may include an indicator indicating which bearer is a default bearer to indicate the default bearer to the terminal.

[0267] Fig.24 The configuration of a terminal and the configuration of a base station to which the method for establishing flow-based QoS according to an embodiment of the present disclosure is applied are shown.

[0268] At this time, the flow can refer to the IP flow and can refer to the SDF. The SDF can be represented by the IP flow group.

[0269] Reference Fig.24In the case of uplink, the terminal 2410 can allocate QoS to the uplink flow using mapping information about QoS and the uplink flow or a packet tag indicating QoS through a packet marker / QoS mapper (PMQM) 2415 which is a higher layer or device of the packet data convergence protocol (PDCP), and allocate the uplink flow to an appropriate bearer 2417 having a QoS corresponding to the QoS. Meanwhile, as long as the PMQM 2415 is a layer or device that performs operations of allocating QoS as described above and allocating the uplink flow to an appropriate bearer 2417 having a QoS corresponding to the QoS, any device may correspond thereto regardless of the terminology. For example, the PMQM 2415 may be referred to as a service data adaptation protocol (SDAP), a packet data adaptation protocol (PDAP), etc., and may map between a data radio bearer and a QoS flow, and mark QoS information to an uplink packet and a downlink packet.

[0270] If there is no bearer suitable for the QoS of the uplink flow, the PMQM 2415 may assign the uplink flow to a default bearer 2417 .

[0271] At the same time, the base station 2420 can use mapping information about QoS and flow or a packet tag indicating QoS to confirm the QoS of the uplink flow received from the terminal 2410, and confirm whether the QoS of the uplink flow matches the QoS of the bearer to which the uplink flow is sent in a layer or device called PMQM 2425.

[0272] If the uplink flow matches the QoS of the bearer, the base station 2420 may send the uplink flow to the NGCN. If the QoS of the uplink flow does not match the QoS of the bearer to which the uplink flow is sent, the PMQM 2425 interacts with the RRC layer 2423 to newly establish a bearer 2427 suitable for the QoS of the uplink flow with the terminal 2410. Thereafter, the base station 2420 may send the uplink flow through the newly established bearer 2427.

[0273] At the same time, refer to Fig.24In the case of a downlink, the base station 2420 may analyze the QoS of the downlink flow received from the NGCN using mapping information about the QoS and the flow or a packet marking indicating the QoS through a layer or device called PMQM 2425 located at a higher part of the Packet Data Convergence Protocol (PDCP) layer, and allocate the downlink flow to a bearer 2427 having a QoS that matches the QoS of the downlink. Meanwhile, as long as the PMQM 2425 is a layer or device that performs the operation of allocating QoS as described above and allocating the downlink flow to an appropriate bearer 2427 having a QoS corresponding to the QoS, any device may correspond thereto regardless of the terminology. For example, the PMQM 2425 may be called SDAP, PDAP, etc., and may map between a data radio bearer and a QoS flow, and mark QoS information as an uplink packet and a downlink packet.

[0274] If there is no bearer matching the QoS of the downlink flow, a new bearer matching the QoS of the downlink may be established with the terminal 2410 through interaction with the RRC layer 2423. The base station 2420 may send the downlink flow to the terminal 2410 through the newly established bearer. The terminal 2410 may receive the downlink flow through the bearer, and the PMQM 245 may send them to the corresponding application. The terminal 2410 may analyze the QoS of the downlink flow received from the base station 2420 using mapping information about QoS and flow or a packet marking indicating QoS in the PMQM 2415, and use the QoS information and the downlink bearer information for the uplink flow generated as a response to the downlink flow.

[0275] Figure 25 to Figure 27 is a view showing a configuration of a terminal when a terminal to which a method for establishing flow-based QoS according to an embodiment of the present disclosure can be applied interacts with an LTE system and a next-generation wireless communication system.

[0276] At this time, the flow can refer to the IP flow and can refer to the SDF. The SDF can be represented by the IP flow group.

[0277] Reference Fig.25, the terminal 2510 can segment the uplink flow into NR (5G) flow and LTE (4G) flow in a layer or device called a packet marker / QoS mapper (PMQM) 2530 located in a higher part of the PDCP layer. PMQM 2530 can analyze the mapping information about QoS and flow or the packet marking indicating QoS, and allocate the NR flow to the bearer 2545 suitable for the QoS of each flow to send the NR flow to the NR base station (rNB). If there is no bearer suitable for the QoS of the flow, PMQM 2530 can allocate the flow to a default bearer. In addition, PMQM 2530 can send the LTE flow in the uplink flow to a service flow template (TFT) 2553. After applying the QoS rules, the LTE flow sent to TFT 2553 can be mapped to the EPS bearer 2555 according to the TFT filtering rules.

[0278] The terminal 2510 can analyze the QoS of the downlink received from the LTE or NR base station using the mapping information about QoS and flow or the packet marking indicating QoS in the PMQM 2530, and use the QoS information and downlink bearer information for the uplink flow generated in response to the downlink flow.

[0279] In addition, in order to send data to the NR bearer and the LTE base station for the same bearer, it is possible to consider Fig.26 and Fig. 27 The terminals 2610 and 2710 shown in FIG. At this time, the terminals 2610 and 2710 can perform interactions such as 2660 and 2770.

[0280] Fig.28 A scenario of interaction between a base station (rNB) of a next generation wireless communication system and a base station (eNB) of an LTE system to which a method for establishing flow-based QoS according to an embodiment of the present disclosure is applied is shown.

[0281] At this time, the flow can refer to the IP flow and can refer to the SDF. The SDF can be represented by the IP flow group.

[0282] Fig.28A scenario in which the NR base station 2810 operates as a MeNB and the LTE base station 2820 operates as a SeNB is shown. A layer or device called a packet marker / QoS mapper (PMQM) 2815 of the NR base station 2810 analyzes the QoS using mapping information about QoS and flow or a packet marker indicating the QoS of the downlink flow, and allocates the downlink flow to a bearer 2817 suitable for the analyzed QoS to transmit the downlink flow. The PDCP layer 2817 may transmit a packet of a bearer corresponding to the PDCP layer 2817 to an RLC layer 2819 bearer of the LTE base station 2820 suitable for the QoS of the PDCP layer bearer to interact with the LTE base station 2820. If there is no RLC layer of the LTE base station 2820 suitable for the QoS of the PDCP layer bearer, the NR RRC layer 2813 and the LTE RRC layer 2823 may interact with each other to generate a bearer of an appropriate RLC layer.

[0283] Fig.29 Another scenario of interaction between a base station (rNB) of a next generation wireless communication system and a base station (eNB) of an LTE system to which the method for establishing flow-based QoS according to an embodiment of the present disclosure is applied is shown.

[0284] Reference Fig.29 , Fig.29 A scenario is shown in which the LTE base station 2910 operates as a MeNB and the NR base station 2920 operates as a SeNB. If the LTE base station 2910 receives downlink data with QoS based on bearer processing, in order to interact with the NR base station 2920 in the PDCP layer 2917, the LTE base station may send a packet of a bearer 2911 corresponding to the PDCP layer 2917 to the RLC layer 2929 bearer of the NR base station 2920 suitable for the QoS of the PDCP layer bearer. If there is no RLC layer of the NR base station 2910 suitable for the QoS of the PDCP layer bearer, the LTE RRC layer 2913 and the NR RRC layer 2923 may interact with each other to generate a suitable RLC layer bearer.

[0285] Fig.30 The configuration of a terminal according to an embodiment of the present disclosure is shown.

[0286] Reference Fig.30 , a terminal according to an embodiment of the present disclosure may include a transceiver 3010 and a controller 3040. The terminal includes a multiplexer / demultiplexer 3020, a control message processor 3060, various high-layer processors 3030 and 3035, a layer or device called a packet marker / QoS mapper (PMQM) 3050, and a NAS layer device 3070.

[0287] The transceiver 3010 may receive data and a predetermined control signal through a forward channel of a serving cell, and transmit data and a predetermined control signal through a reverse channel. If multiple serving cells are configured, the transceiver 3010 may transmit and receive data and control signals through multiple serving cells.

[0288] The multiplexer / demultiplexer 3020 can be used to multiplex data generated from the higher layer processors 3030 and 3035 or the control message processor 3060, or demultiplex data received by the transceiver 3010 and transmit the data to the appropriate higher layer processors 3030 and 3035 or the control message processor 3060.

[0289] The control message processor 3060 is an RRC layer device and processes a control message received from the base station to perform a required operation. For example, when an RRC CONNECTION SETUP message is received, the control message processor 3060 configures a signaling radio bearer (SRB) and a temporary DRB.

[0290] A layer or device referred to as PMQM 3050 can use mapping information about QoS and flow or a packet marking indicating QoS to allocate the QoS of the uplink flow, and allocate the uplink flow to appropriate bearers 3030 and 3035 having a QoS corresponding to the QoS. If there is no bearer suitable for the QoS of the uplink flow, PMQM 3050 can allocate the uplink flow to the default bearer 2417. PMQM 3050 can analyze the QoS of the downlink flow received from the base station 2420 using mapping information about QoS and flow or a packet marking indicating QoS, and use the QoS information and downlink bearer information for the uplink flow generated as a response to the downlink flow. Meanwhile, as long as PMQM 3050 is a layer or device that performs the mapping between data radio bearers and QoS flows and marks the QoS information of uplink packets and downlink packets, any device can correspond to this regardless of the terminology. For example, PMQM 3050 can be referred to as a service data adaptation protocol (SDAP), a packet data adaptation protocol (PDAP), etc.

[0291] The high-level processors 3030 and 3035 represent DRB devices and can be configured for each service. The high-level processors 3030 and 3035 can process data generated from user services such as file transfer protocol (FTP) and Internet voice protocol (VoIP) and send the processed data to the multiplexer and demultiplexer 3020, or process data sent from the multiplexer and demultiplexer 3020 and send them to a high-level service application. One service can be mapped one to one with one EPS bearer and one high-level processor on a one-to-one basis.

[0292] The controller 3040 can control the overall operation of the terminal to perform any one of the operations of the above-mentioned embodiments. For example, the controller 3040 can control the transceiver 3010 and the multiplexer and demultiplexer 3020 to confirm the scheduling command received by the transceiver 3010, for example, reverse authorization to control the multiplexer and demultiplexer 3010 to perform reverse transmission to the appropriate transmission resource at the appropriate time. For this purpose, the controller 3040 may include a circuit, a dedicated circuit or at least one processor. For example, the controller 3040 may include a communication processor (CP) for performing control for communication and an application processor (AP) for controlling a high level such as an application program. In addition, the operation of the terminal can be realized by including a memory device storing corresponding program codes in any component of the terminal. That is, the controller 3040 can perform the above operations by reading and executing the program code stored in the memory device by a processor, a central processing unit (CPU), etc. The controller 3040 can be electrically connected to other components, for example, the transceiver 3010.

[0293] Fig.31 The configuration of a base station, an MME, and an S-GW according to an embodiment of the present disclosure is shown.

[0294] Reference Fig.31 , a block diagram illustrating the configuration of a base station, an MME 3195, and an S-GW 3190 according to an embodiment of the present disclosure is shown. At this time, the base station may include a transceiver 3110 and a controller 3140. The base station may also include a multiplexer / demultiplexer 3120, a control message processor 3160, various high-level processors 3130 and 3135, a scheduler 3180, and a layer or device 3150 called a packet marker / QoS mapper (PMQM). The MME may include a NAS layer device 3197.

[0295] The transceiver 3110 may transmit data and a predetermined control signal through a forward carrier and receive data and a predetermined control signal through a reverse carrier. If multiple carriers are configured, the transceiver 3110 may transmit and receive data and control signals through the multiple carriers.

[0296] The multiplexer / demultiplexer 3120 is used to multiplex data generated from the upper layer processors 3130 and 3135 or the control message processor 3160 or demultiplex data received by the transceiver 3110 and send the data to the appropriate upper layer processors 3130 and 3135, the control message processor 3160 or the controller 3140.

[0297] The control message processor 3160 may allow the terminal to process the transmitted control message to perform a desired operation or generate a control message to be transmitted to the terminal, and transmit the generated control message to a lower layer.

[0298] The layer or device referred to as PMQM 3150 can analyze the QoS of the uplink flow using the mapping information about QoS and the flow or the packet marking indicating the QoS, and allocate the downlink flow to the appropriate bearers 3130 and 3135 having the QoS corresponding to the QoS. If there is no bearer suitable for the QoS of the uplink flow, the PMQM 3150 can generate the QoS of the downlink flow. Meanwhile, as long as the PMQM 3150 is a layer or device that performs the mapping between the data radio bearer and the QoS flow and marks the QoS information of the uplink packet and the downlink packet, any device can correspond to this regardless of the terminology. For example, the PMQM 3150 can be referred to as the Service Data Adaptation Protocol (SDAP), the Packet Data Adaptation Protocol (PDAP), etc.

[0299] The upper layer processors 3130 and 3135 may be configured for each EPS bearer. The upper layer processors 3030 and 3035 may configure data sent from the PMQM device 3150 into an RLC PDU and send the RLC PDU to the multiplexer and demultiplexer 3120, or configure the RLC PDU sent from the multiplexer and demultiplexer 3120 into a PDCP SDU and send the PDCP SDU to the PMQM device 3150.

[0300] The scheduler 3180 allocates transmission resources to the terminal at appropriate timing in consideration of a buffer state and a channel state of the terminal, etc., and allows the transceiver 3130 to process a signal transmitted from the terminal or perform a process of transmitting a signal to the terminal.

[0301] The PMQM device 3150 processes data transmitted from a lower layer processor and transmits the processed data to a next network node.

[0302] The higher layer processors 3130 and 3135 and the PMQM device 3150 are interconnected through bearers and flows. The NAS layer device 3197 processes the IP packets included in the NAS message and transfers the processed IP packets to the S-GW 3190.

[0303] The controller 3140 can control the overall operation of the base station to perform any one of the operations of the above-mentioned embodiments. For example, the controller 3140 can control the PMQM 3150 to analyze the QoS of the uplink flow using the mapping information about the QoS and the flow or the packet marking indicating the QoS, and allocate the downlink flow to the appropriate bearers 3130 and 3135 with the QoS corresponding to the QoS. In addition, if there is no bearer suitable for the QoS of the uplink flow, the controller 3140 can control the PMQM 3150 to generate a bearer corresponding to the QoS of the downlink flow. For this purpose, the controller 3140 may include a circuit, a dedicated circuit, or at least one processor. For example, the controller 3140 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls a high layer such as an application. In addition, the operation of the base station can be implemented by including a memory device storing corresponding program codes in any component of the terminal. That is, the controller 3140 can perform the above operations by reading and executing the program codes stored in the memory device by a processor, a central processing unit (CPU), etc. The controller 3140 can be electrically connected to other components, for example, a transceiver 3110.

[0304] Hereinafter, the operating principle of the present disclosure will be described in detail with reference to the accompanying drawings. Hereinafter, when it is determined that the detailed description of the known technology related to the present disclosure may obscure the main purpose of the present disclosure, its detailed description will be omitted. In addition, the following terms are defined in consideration of the functions in the present disclosure, and these terms may be interpreted in different ways by the intention or practice of the user and the operator. Therefore, their definitions should be interpreted based on the contents in the entire specification. For ease of explanation, the terms used in the following description to identify access nodes, terms indicating network entities, terms indicating messages, terms indicating interfaces between network entities, terms indicating various types of identification information, etc. are exemplified. Therefore, the present disclosure is not limited to the terms to be described below, and other terms indicating objects with equivalent technical meanings may be used.

[0305] Hereinafter, for convenience of explanation, the present disclosure uses the terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) or the terms and names modified based on the terms and names. However, the present disclosure is not limited to the terms and names, but can also be equally applied to systems according to other standards.

[0306] The present disclosure relates to reselecting a serving beam of a terminal in a beam-based NR system, and more particularly, to a method and apparatus for measuring adjacent beams using a differential threshold.

[0307] Recently, mobile communication systems have been developed by combining various new technologies to meet the rapidly growing demand for data services and various services. Specifically, discussions on 5G (5th generation), which is a next-generation mobile communication system that reflects the demand, are actively underway. The 5G system is also referred to as a new radio access technology (hereinafter referred to as NR). Compared with the existing LTE and LTE-A, the NR system aims to provide ultra-high-speed data services of several Gbps using ultra-widebands above 100MHz. However, since it is difficult to ensure an ultra-wideband frequency of 100MHz or higher in the frequency bands of several hundred MHz or several GHz used in LTE and LTE-A, the NR system considers operating in very high frequency bands of several GHz or tens of GHz. Since the wavelength of the radio waves used in the above-mentioned very high frequency bands is several millimeters (mm), it is called millimeter wavelength (mmWave). Since the frequency band and path loss of radio waves are proportional to each other, the path loss of radio waves is large at very high frequencies, and thus the service area becomes smaller. In order to overcome the disadvantage of reduced service area in the NR system, beamforming technology has been emphasized to increase the reach of radio waves by converging the radiation energy of radio waves using multiple antennas. Beamforming technology can be applied to both the transmitting end and the receiving end. In addition to expanding the service area, beamforming technology also has the effect of reducing interference due to the convergence of physical beams in the target direction.

[0308] Fig.32 The structure of the NR system according to an embodiment of the present disclosure is shown.

[0309] Reference Fig.32 , a cell served by a NR base station (NR Node B, NR NB, gNB) 3230 based on beam operation includes multiple transmit receive points (TRPs) 3220, 3221, 3222, 3223, 3224, 3225, and 3226. TRPs 3220, 3221, 3222, 3223, 3224, 3225, and 3226 are blocks that separate only the functions of transmitting and receiving physical signals from an existing LTE base station (eNB), and may be configured by multiple antennas. Specifically, TRPs 3220, 3221, 3222, 3223, 3224, 3225, and 3226 may generate beams in various directions by using multiple transmit and receive antennas to perform beamforming, and may be referred to as beam groups (BGs). The user terminal 3210 can access the NR base station 3230 and the external network through TRPs 3220, 3221, 3222, 3223, 3224, 3225 and 3226. In order to serve the user's business, the NR base station 3230 collects and schedules status information (such as the buffer status, available transmission power status and channel status of the terminal 3210) to support the connection between the terminal 3210 and the core network (CN).

[0310] In addition, the MME 3240 in the NR system can be used to perform various control functions and mobility management functions for the terminal 3210, and can be connected to multiple base stations 3230. In addition, the S-GW 3240 is a device that provides data bearers. In addition, the MME and S-GW 3240 can also perform authentication, bearer management, etc. for the terminal 3210 connected to the network, and can process packets arriving from the base station 3230 and packets to be sent to the base station 3230. At the same time, the MME / S-GW 3240 can be configured with an access and mobility management function (AMF), a user plane function (UPF), and a session management function (SMF).

[0311] Fig.33 The frame structure of an NR system operating in a beam-based manner according to an embodiment of the present disclosure is shown.

[0312] Reference Fig.33 , the radio frame 3305 of the NR system is configured by multiple subframes 3310. Specifically, the subframe 3310 of the NR system can be configured by two types: overhead subframe (osf) 3315 and data subframe (dsf) 3320.

[0313] The overhead subframe 3315 is a subframe that transmits an overhead signal required for beam selection. The overhead subframe 3315 transmits different overhead signals for each symbol of the configuration subframe in a beam scanning manner. The overhead subframe 3315 includes a primary synchronization signal (PSS) for acquiring the timing of an orthogonal frequency division multiplexing (OFDM) symbol, a secondary synchronization signal (SSS) for detecting a cell ID, an extended synchronization signal (ESS) for identifying subframe timing, and a beam reference signal (BRS) for identifying a beam. In addition, one or more overhead subframes 3315 may be present in the radio frame 3305. In the figure shown, the overhead subframe 3315 is transmitted in the 0th and 25th subframes.

[0314] The data subframe 3320 is a subframe in which actual data transmitted to a specific terminal is transmitted, and different beam patterns may be applied according to the geographical distribution of the terminals.

[0315] The TRP 3325 performs beam scanning in different directions for each symbol during the overhead subframe 3315, so that resources for transmission to / reception from the terminal are allocated to each beam (3330, 3335, and 3340) within the data subframe 3320. If the beam direction transmitted by the TRP 3325 does not match the position of the terminal, the terminal may not receive any signal of the corresponding data subframe. In addition, one TRP 3325 can transmit multiple data subframes during one radio frame 3305, and the terminal can receive multiple beams from multiple TRPs 3325 according to the position of the terminal itself.

[0316] Fig.34 The process of a terminal reselecting a cell in an LTE system according to an embodiment of the present disclosure is shown.

[0317] Cell reselection is a process for determining which cell a terminal resides in when the service quality of a serving cell is lower than that of a neighboring cell due to the movement of a terminal in an idle state. The handover determination is made by the network (MME or source eNB), while the cell reselection is determined by the terminal based on the measurement value. In addition, the cell reselected when the terminal moves can be a cell using the same LTE frequency (inter-frequency) as the currently residing serving cell, a cell using a different LTE frequency (inter-frequency), or a cell using other radio access technologies (inter-RAT).

[0318] Reference Fig.34 , the terminal in the idle state performs a series of operations while camping on the serving cell in step 3410. First, in step 3420, the terminal may receive a system information block (SIB) broadcasted by the base station of the serving cell. For reference, MIB, SIB 1 and SIB 2 are system information generally applied to all UEs, and SIB 3 to SIB 8 may include information required for the terminal in the idle state to reselect a cell. The system information may include a threshold for determining whether to measure a neighboring cell signal, a parameter for calculating the ranking of the serving cell and the neighboring cell, etc.

[0319] The terminal in the idle state may wake up in each discontinuous reception (DRX) cycle in step 3430 to measure the absolute reference signal received quality (RSRP) (Q rxlevmeas ) and relative reference signal received power (RSRP) (Q qualmeas ). The terminal uses the measured values ​​and the parameters received from the base station to calculate the reception level (Srxlev) and reception quality (Squal) of the serving cell, and compares these values ​​with the threshold to determine whether to reselect the cell. The reception level Srxlev and reception quality Squal of the serving cell can be obtained by the following equations:

[0320] Srxlev=Q rxlevmeas -(Q rxlevmin +Q rxlevminoffset )-Pcompensation-Qoffset temp

[0321] Squal=Qqualmeas-(Q qualmin +Q qualminoffset )-Qoffset temp

[0322] The definitions of the parameters used in this article refer to the 3GPP standard documents.

[0323] In step 3440, the terminal determines whether the signal strength and quality of the serving cell obtained from the measurement value is less than a threshold value (eg, Srxlev IntraSearchP or Squal IntraSearchQ ) to determine whether to trigger cell reselection.

[0324] If the above conditions are not met (ie, if the signal strength and quality of the serving cell obtained from the measurement values ​​become less than the threshold), then in step 3450, the terminal continues to camp on the corresponding serving cell without performing cell reselection.

[0325] However, if the cell reselection is triggered by satisfying the above conditions (i.e., if the signal strength and quality of the serving cell obtained from the measurement value become less than the threshold), then in step 3460, the terminal may measure the neighboring cell based on the priority. According to an embodiment, for a high priority inter-frequency / inter-RAT cell, the neighboring cell measurement may be started regardless of the quality of the serving cell. In addition, if the signal strength and quality of the serving cell become less than the threshold value (S) received as system information for an inter-frequency cell having the same priority as or lower than the serving cell, the neighboring cell measurement may be started. nonIntraSearchP and S nonIntraSearchQ ), that is, if Srxlev nonIntraSearchP or Squal nonIntraSearchQ , you can start measuring neighboring cells.

[0326] After completing the measurement of the neighboring cells in step 3460, the terminal may perform cell reselection based on the priority in step 3470. First, for the reselection of the high-priority inter-frequency / inter-RAT cell, if the signal quality of the corresponding cell is greater than the threshold Thresh X，HighQ Treselection RAT (Squal>Thresh X，HighQ ), the terminal can reselect the corresponding cell. Second, for low-priority inter-frequency cell reselection, first, determine whether the signal quality of the serving cell is less than the threshold Thresh Serving，LowQ Conditions <Thresh Serving，LowQ ), and if it is determined that the condition is met, whether the signal quality of the inter-frequency cell is greater than the threshold Thresh X，LowQ Treselection RAT (Squal>Thresh X，LowQ ). Third, for intra-frequency / inter-frequency cell reselection with the same priority, the rank is determined cell by cell based on the measurement values ​​(RSRP) from neighboring cells. ​​​​

[0327] The ranking of the serving cell and the neighboring cell can be calculated by the following equation:

[0328] R s =Q meas,s +Q Hyst -Qoffset temp

[0329] R n =Q meas,n -Qoffset-Qoffset temp

[0330] In the above equation, Q meas，s is the RSRP measurement value of the serving cell, Q meas，n is the RSRP measurement value of the neighboring cell, Q Hyst is the hysteresis value of the serving cell, Qoffset is the offset between the serving cell and the neighboring cell, and Qoffset temp is an offset temporarily applied to the cell. When the rank of the neighboring cell obtained from the above equation is greater than the rank of the serving cell (Rn>Rs), the terminal can camp on the best cell among the neighboring cells.

[0331] If cell reselection is determined in the above process, the terminal receives system information from the corresponding cell in step 2480 and performs a suitability check on whether the new serving cell can receive service. If the tracking area identifier (TAI) is not in the TAI list of the terminal, a tracking area update (TAU) procedure is performed. If the corresponding cell is determined to be a new cell, operations to the serving cell (system information acquisition, paging monitoring, serving cell signal measurement, etc.) may be performed.

[0332] At the same time, the number of beam measurements in the beam-based NR system is greater than the number of measurements on the cell in LTE. A beam group consists of at least one beam, wherein the reference signal of each beam is sent in the same overhead subframe and is scrambled by at least one code initialized with the same value. That is, the base station sends multiple beams for each TRP by dividing the time domain in the overhead subframe, and the terminal measures the strength of the beam sent by the TRP in the overhead subframe for each receiving beam of the terminal. The above-mentioned intra-TRP beam measurement cost is low (here, the number of times the measurement is required), but in the case of inter-TRP beam measurement, beam measurement needs to be performed from several TRPs, so the search cost increases. In addition, inter-frequency beam measurement is not performed simultaneously with intra-frequency beam measurement, so that more RF resources are required. That is, since there is a large difference in the complexity of the beam measurement process according to the type of cell performing the beam measurement, in the present disclosure, a process for differentially applying the conditions for performing beam measurement according to the type of adjacent cells will be described.

[0333] Fig.35 A method for a terminal to reselect a serving beam in an NR system according to an embodiment of the present disclosure is shown.

[0334] Referring to Fig.35 , in step 3510, an idle NR terminal may camp on the nth beam of the serving TRP. In step 3520, the terminal may monitor paging messages.

[0335] In step 3530, the terminal receives system information through the serving beam, and in step 3540, the terminal may measure the serving beam and adjacent beams.

[0336] If the measurement result of the adjacent beam corresponds to beam reselection, the terminal may reselect the beam in step 3550.

[0337] Fig.36 An example 1 of beam measurement in an NR system according to an embodiment of the present disclosure is shown.

[0338] Referring to Fig.36 , the NR terminal includes a neighboring beam measurement process for measuring the signal strength and quality of the serving beam and sequentially determining the measurement of the neighboring beam. Specifically, three thresholds (Thres 1>Thres 2>Thres 3) are introduced to define different beam measurements according to the type of neighboring cell.

[0339] In step 3610, the NR terminal may measure the strength and quality of the downlink beam reference signal of the serving beam. According to an embodiment, the downlink beam reference signal may be sent / received through the overhead subframe of the corresponding TRP / BG.

[0340] In step 3620, the terminal compares the serving beam quality with threshold 1 (Thres 1) (the first threshold) and determines whether serving beam quality < Thres 1 is satisfied.

[0341] If serving beam quality < Thres 1 is not satisfied, the terminal may not perform neighboring beam measurement in step 3630. That is, in this case, since the service quality of the serving beam is good, beam reselection is not performed.

[0342] However, if serving beam quality < Thres 1 is satisfied, in step 3640, the terminal may start neighboring beam measurement within the TRP. That is, the terminal may start measuring other beams transmitted in the TRP (e.g., TRP 1) including the serving beam.

[0343] In step 3650, the terminal compares the serving beam quality with a threshold 2 (Thres 2) (second threshold) and determines whether serving beam quality < Thres 2 is satisfied.

[0344] If serving beam quality < Thres 2 is not satisfied, in step 3660, the terminal may start measuring adjacent beams within the TRP (e.g., TRP1).

[0345] However, if serving beam quality < Thres 2 is satisfied, in step 3670, the terminal may start measuring adjacent beams between TRPs. That is, the terminal may start measuring beams transmitted in a TRP (e.g., TRP 2) that does not include the serving beam.

[0346] In step 3680, the terminal compares the serving beam quality with a threshold 3 (Thres 3) (third threshold) and determines whether serving beam quality < Thres 3 is satisfied.

[0347] If serving beam quality < Thres 3 is not satisfied, in step 3690, the terminal may start measuring adjacent beams between TRPs (e.g., TRP2).

[0348] However, if serving beam quality < Thres 3 is satisfied, in step 3695, the terminal may start measuring adjacent beams between TRPs (e.g., TRP3). That is, the terminal may start measuring beams transmitted in adjacent beams having different center frequencies.

[0349] Through the above process, the terminal can complete the measurement of the serving beam and adjacent beams and perform beam reselection based on the measurement values.

[0350] Fig.37 and Fig.38 shows Example 2 of beam measurement on an NR system according to an embodiment of the present disclosure.

[0351] According to an embodiment, conditions for establishing differential thresholds and determining beam measurement are defined according to the type of adjacent cell.

[0352] Referring to Fig. 27 , in step 3730, the terminal 3710 camps on the nth beam 3720 of any TRP / BG, and in step 3735, the terminal 3710 may monitor paging messages.

[0353] In step 3740, the terminal 3710 may measure the strength and quality of the downlink beam reference signal of the serving beam. According to an embodiment, the downlink beam reference signal may be transmitted / received through an overhead subframe of the corresponding TRP / BG.

[0354] In step 3745, the terminal 3710 may compare the strength and quality of the downlink beam reference signal of the serving beam with a predetermined reference value. The terminal 3710 may determine the range of the beam to be measured based on the comparison result.

[0355] Reference Fig.38 , three thresholds may be set according to the strength 3810 of the received signal and the quality 3820 of the received signal, respectively, so as to determine the beam measurement range. For example, the thresholds Thres_RP 1 (first received signal strength threshold) 3830, Thres_RP 2 (second received signal strength threshold) 3835, and Thres_RP 3 (third received signal strength threshold) 3837 (Thres_RP 1>Thres_RP 2>Thres_RP 3) may be defined according to the strength 3810 of the received signal. According to an embodiment, the number of thresholds may be equal to or less than 2 or equal to or greater than 4. For example, Thres_RQ 1 (first received signal quality threshold) 3840, Thres_RQ 2 (second received signal quality threshold) 3845, and Thres_RQ 3 (third received signal quality threshold) 3847 (Thres_RQ 1>Thres_RQ 2>Thres_RQ 3) may be defined according to the quality 3820 of the received signal. According to an embodiment, the number of thresholds may be equal to or less than 2 or equal to or greater than 4. The thresholds (Thres_RP 1, Thres_RP 2, Thres_RP 3, Thres_RQ 1, Thres_RQ 2, Thres_RQ 3) may be included in the system information, and the terminal 3710 may also receive them through the corresponding service beam.

[0356] In addition, the terminal 3710 can determine the following four beam measurement ranges by comparing the measurement results with the receiving threshold: (1) only measure the service beam (no adjacent beam measurement); (2) perform measurement on the adjacent beam belonging to the same beam group as the service beam (intra-TRP / BG measurement); (3) perform measurement on the adjacent beam that belongs to a different beam group as the service beam but has the same center frequency as the service beam (inter-TRP / BG measurement); (4) perform measurement on the adjacent beam that has a different center frequency from the service beam (inter-frequency measurement).

[0357] A table of mapping conditions and actions may be established to determine the beam range to be measured, as shown in [Table 1] below.

[0358] [Table 1]

[0359]

[0360] The following operations are steps to determine the beam range to be measured by referring to the table above.

[0361] Refer again Fig.37 , if the service beam reference signal strength and quality meet the first condition in step 3750, then in step 3755, the terminal 3710 can only measure the service beam (e.g., the service beam of TRP 13720).

[0362] In step 3760, if the service beam reference signal strength and quality meet the second condition, then in step 3765, the terminal 3710 can measure the adjacent beams (e.g., the adjacent beams of the service beam of TRP 1 3720) belonging to the same beam group as the service beam (e.g., the service beam of TRP 1 3720).

[0363] In step 3770, if the service beam reference signal strength and quality satisfy the third condition, then in step 3775, the terminal 3710 may measure an adjacent beam (e.g., the beam of TRP 2 3723) that belongs to a different beam group as the service beam (e.g., the service beam of TRP 1 3720) but has the same center frequency FB 1 as the center frequency of the service beam.

[0364] In step 3780, if the service beam reference signal strength and quality satisfy the fourth condition, then in step 3785, the terminal 3710 may measure an adjacent beam (e.g., the beam of TRP 3 3725) having a center frequency FB 2 that is different from the center frequency of the service beam (e.g., the service beam of TRP 1 3720).

[0365] Thereafter, in step 3790 , a new serving beam may be reselected based on the measurement result of the terminal 3710 .

[0366] Fig.39 The operation of a terminal according to Example 2 for the terminal to reselect a serving beam in an NR system according to an embodiment of the present disclosure is illustrated.

[0367] Reference Fig.39 In step 3910, the NR terminal in the idle state may reside in the nth beam of the serving TRP, and in step 3520, the terminal may monitor the paging message. In step 3930, the terminal may receive system information through the serving beam, and in step 3940, the terminal may measure the serving beam.

[0368] In step 3950, the terminal may compare the measurement result of the serving beam with the threshold used to determine the beam measurement range to determine the operating condition. At this time, the terminal may determine the beam to be measured by referring to the above-mentioned beam range determination table (Table 1).

[0369] In step 3960, the beam of the corresponding TRP / BG may be measured according to the mapping rule determined in the previous step. In step 3970, the terminal may reselect the beam based on the measurement results of the adjacent beams.

[0370] Fig.40 The configuration of a terminal according to an embodiment of the present disclosure is shown.

[0371] Reference Fig.40 , the terminal according to an embodiment of the present disclosure may include a transceiver and a controller 3040. The terminal may also include a memory 4030. At this time, the transceiver may be a radio frequency (RF) processor 4010. In an embodiment, the transceiver may include an RF processor 4010 and a baseband processor 4020.

[0372] The RF processor 4010 is used to transmit / receive signals through a radio channel, such as frequency band conversion and signal amplification. That is, the RF processor 4010 can up-convert the baseband signal provided from the baseband processor 4020 into an RF band signal, then transmit the RF band signal through an antenna, and down-convert the RF band signal received through the antenna to the baseband. For example, the RF processor 4010 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc. Fig.40 Only one antenna is shown, but the terminal may include multiple antennas. In addition, the RF processor 4010 may include multiple RF chains. In addition, the RF processor 4010 may perform beamforming. For beamforming, the RF processor 4010 may adjust the phase and size of each signal sent and received by multiple antennas or antenna elements. In addition, the RF processor 4010 may perform MIMO and may receive multiple layers when performing MIMO operations. The RF processor 4040 may perform receive beam scanning by appropriately configuring multiple antennas or antenna elements under the control of the controller 4010, or adjust the direction and beam width of the receive beam so that the receive beam resonates with the transmit beam.

[0373] The baseband processor 4020 performs a conversion function between a baseband signal and a bit string according to the physical layer standard of the system. For example, when sending data, the baseband processor 4020 generates a complex symbol by encoding and modulating the transmitted bit string. In addition, when receiving data, the baseband processor 4020 can recover the received bit string by demodulating and decoding the baseband signal provided from the RF processor 4010. For example, according to the OFDM scheme, when sending data, the baseband processor 4020 can generate a complex symbol by encoding and modulating the transmitted bit string, mapping the complex symbol to a subcarrier, and then configuring the OFDM symbol by an inverse fast Fourier transform (IFFT) operation and CP (cyclic prefix) insertion. In addition, when receiving data, the baseband processor 4020 divides the baseband signal provided from the RF processor 4010 in OFDM symbol units, and recovers the signal mapped to the subcarrier by a fast Fourier transform (FFT) operation, and then recovers the received bit string by modulation and decoding.

[0374] As described above, the baseband processor 4020 and the RF processor 4010 can send and receive signals. Therefore, the baseband processor 4020 and the RF processor 4010 can be referred to as a transmitter, a receiver, a transceiver, or a communicator. In addition, at least one of the baseband processor 4020 and the RF processor 4010 may include multiple communication modules to support a variety of different radio access technologies. In addition, at least one of the baseband processor 4020 and the RF processor 4010 may include different communication modules to process signals of different frequency bands. For example, different radio access technologies may include LTE networks, NR networks, etc. In addition, different frequency bands may include ultra-high frequency (SHF) (e.g., 2.5 GHz, 5 GHz, etc.) bands, millimeter wave (e.g., 60 GHz, etc.) bands.

[0375] The memory 4030 stores data such as basic programs, application programs, and configuration information for operation of the terminal. The memory 4030 may provide the stored data according to a request of the controller 4040.

[0376] The controller 4040 can control the overall operation of the terminal to perform any one of the operations of the above-mentioned embodiments. For example, the controller 4040 can send / receive signals through the baseband processor 4020 and the RF processor 4010. In addition, the controller 4040 can record data in the memory 4030 and read data from the memory 4030. For this purpose, the controller 4040 may include a circuit, a dedicated circuit, or at least one processor. For example, the controller 4040 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls a high level such as an application. In addition, the operation of the terminal can be implemented by including a memory device storing corresponding program codes in any component of the terminal. That is, the controller 4040 can perform the above-mentioned operations by reading and executing the program codes stored in the memory device by a processor, a central processing unit (CPU), etc. In addition, according to an embodiment of the present disclosure, the controller 4040 may include a multi-connection processor 4045 to perform processing to be operated in a multi-connection mode. The controller 4040 may be electrically connected to other components, for example, a transceiver 4010.

[0377] Fig.41 The configuration of a base station according to an embodiment of the present disclosure is shown.

[0378] Reference Fig.41 , a base station (or a transmit receive point (TRP)) according to an embodiment of the present disclosure may include a transceiver and a controller 4140. The base station may also include a backhaul communication interface 4150 and a memory 4130. At this time, the transceiver may be a radio frequency (RF) processor 4110. According to an embodiment, the transceiver may include an RF processor 4110 and a baseband processor 4120.

[0379] The RF processor 4110 is used to transmit / receive signals through a radio channel, such as frequency band conversion and signal amplification. That is, the RF processor 4110 can up-convert the baseband signal provided from the baseband processor 4120 into an RF band signal, then transmit the RF band signal through an antenna, and down-convert the RF band signal received through the antenna to a baseband signal. For example, the RF processor 4110 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc. Fig.41 Only one antenna is shown, but the base station may include multiple antennas. In addition, the RF processor 4110 may include multiple RF chains. In addition, the RF processor 4110 may perform beamforming. For beamforming, the RF processor 4110 may adjust the phase and size of each signal sent and received through multiple antennas or antenna elements. The RF processor 4110 may perform downlink MIMO operations by sending one or more layers.

[0380] The baseband processor 4120 performs a conversion function between a baseband signal and a bit string according to the physical layer standard of the system. For example, when sending data, the baseband processor 4120 generates a complex symbol by encoding and modulating the transmitted bit string. In addition, when receiving data, the baseband processor 4120 recovers the received bit string by demodulating and decoding the baseband signal provided from the RF processor 4110. For example, according to the OFDM scheme, when sending data, the baseband processor 4120 generates a complex symbol by encoding and modulating the transmitted bit string, maps the complex symbol to a subcarrier, and then performs an IFFT operation and CP insertion to configure an OFDM symbol. In addition, when receiving data, the baseband processor 4120 divides the baseband signal provided from the RF processor 4110 in OFDM symbol units, recovers the signal mapped to the subcarrier by FFT operation, and then recovers the received bit string by modulation and decoding.

[0381] The baseband processor 4120 and the RF processor 4110 can send and receive signals as described above. Therefore, the baseband processor 4120 and the RF processor 4110 can be referred to as a transmitter, a receiver, a transceiver, a communication interface, or a wireless communication interface. In addition, at least one of the baseband processor 4120 and the RF processor 4110 may include multiple communication modules to support a variety of different radio access technologies. In addition, at least one of the baseband processor 4120 and the RF processor 4110 may include different communication modules to process signals of different frequency bands. For example, different radio access technologies may include wireless LANs (e.g., IEEE 802.11, etc.), cellular networks (e.g., LTE, etc.), etc. In addition, different frequency bands may include ultra-high frequency (SHF) (e.g., 2.5 GHz, 5 GHz, etc.) bands, millimeter wave (e.g., 60 GHz, etc.) bands.

[0382] The backhaul communicator 4130 provides an interface for performing communication with other nodes within the network. That is, the backhaul communication interface 4130 can convert a bit string sent from the base station to other nodes (e.g., an auxiliary base station (or other adjacent base stations), a core network, etc.) into a physical signal, and convert a physical signal received from other nodes into a bit string.

[0383] The memory 4130 may store data such as basic programs, applications, and configuration information for base station operation. Specifically, the memory 4130 may store information about the bearer assigned to the accessed terminal, measurement results reported from the accessed terminal, etc. In addition, the memory 4130 may store information as a determination standard for providing multiple connections to the terminal or stopping multiple connections to the terminal. The memory 4130 may provide stored data according to a request from the controller 4140.

[0384] The controller 4140 can control the overall operation of the base station to perform any one of the operations of the above-mentioned embodiments. For example, the controller 4140 can send / receive signals through the baseband processor 4120 and the RF processor 4110 or the backhaul communication interface 4150. In addition, the controller 4140 can record data in the memory 4130 and read data from the memory 4130. For this purpose, the controller 4140 may include a circuit, a dedicated circuit, or at least one processor. For example, the controller 4140 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls a high level such as an application. In addition, the operation of the base station can be implemented by including a memory device storing corresponding program codes in any component of the terminal. That is, the controller 4140 can perform the above-mentioned operations by reading and executing the program codes stored in the memory device by a processor, a central processing unit (CPU), etc. In addition, according to an embodiment of the present disclosure, the controller 4140 may include a multi-connection processor 4145 to perform processing to be operated in a multi-connection mode. The controller 4140 may be electrically connected to other components, for example, a transceiver 4110.

[0385] In the detailed embodiments of the present disclosure, according to the detailed embodiments as described above, the components included in the present disclosure are expressed in the singular or plural. However, the singular or plural expressions are selected to meet the situation proposed for the convenience of explanation, and the present disclosure is not limited to a single component or multiple components, and even if the component is expressed in the plural, the component can also be configured in the singular, or even if the component is expressed in the singular, the component can also be configured in the plural.

[0386] Although exemplary embodiments of the present disclosure have been disclosed for illustrative purposes, various modifications, additions and substitutions may be made without departing from the scope and spirit of the present disclosure disclosed in the appended claims. Therefore, the scope of the present disclosure should not be interpreted as limited to the described embodiments, but is defined by the appended claims and their equivalents.

[0387] Hereinafter, the operating principle of the present disclosure will be described in detail with reference to the accompanying drawings. Hereinafter, when it is determined that the detailed description of the known technology related to the present disclosure may obscure the main idea of ​​the present disclosure, its detailed description will be omitted. In addition, the following terms are defined in consideration of the functions in the present disclosure, and these terms may be interpreted in different ways by the intention or practice of the user and operator. Therefore, their definitions should be interpreted based on the contents in the entire specification.

[0388] For convenience of explanation, terms used in the following description to identify access nodes, terms indicating network entities, terms indicating messages, terms indicating interfaces between network entities, terms indicating various types of identification information, etc. are exemplified. Therefore, the present disclosure is not limited to the terms to be described below, and other terms indicating objects having equivalent technical meanings may be used.

[0389] Hereinafter, for ease of explanation, the present disclosure uses terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE), which is the latest standard in current communication standards. However, the present disclosure is not limited to the terms and names, but can also be equally applied to systems according to other standards. Specifically, the present disclosure can be applied to 3GPP New Radio (NR: 5G mobile communication standard).

[0390] Fig.42 An example of a network structure of an LTE system according to an embodiment of the present disclosure is shown.

[0391] Reference Fig.42 , a wireless communication system (e.g., an LTE system) may include a plurality of base stations (evolved Node Bs (eNBs)) 4220, 4223, 4225, and 4227, a mobility management entity (MME) 4230, and a serving gateway (S-GW) 4240. A user equipment (UE) (or terminal) 4210 is connected to an external network through the base stations 4220, 4223, 4225, and 4227 and the S-GW 4240.

[0392] Base stations 4220, 4223, 4225, and 4227 are access nodes of a cellular network and provide radio access to a terminal 4210 connected to the network. That is, in order to serve the user's business, BSs 4220, 4223, 4225, and 4227 collect and schedule state information such as a buffer state, an available transmission power state, and a channel state of the terminal 4210 to support a connection between the terminal 4210 and a core network (CN). MME 4230 is a device for performing various control functions of the terminal 4210 and a mobility management function, and is connected to a plurality of base stations 4220, 4223, 4225, and 4227. In addition, S-GW 4240 is a device for providing data bearers. In addition, MME 4230 and S-GW 4240 can also perform authentication, bearer management, etc. for the terminal 4210 connected to the network, and process packets arriving from base stations 4220, 4223, 4225 and 4227 and packets to be sent to base stations 4220, 4223, 4225 and 4227.

[0393] Fig.43 The radio protocol structure of the LTE system according to an embodiment of the present disclosure is shown.

[0394] Reference Fig.43 , the radio protocol of the LTE system is composed of the Packet Data Convergence Protocol (PDCP) 4310 and 4330 in the UE and the BS (ENB), respectively, the Radio Link Control (RLC) 4315 and 4335, and the Medium Access Control (MMC) 215 and 230. The PDCP 4310 and 4330 are responsible for the operation of IP header compression / recovery, etc., and the RLC 4315 and 4335 reconfigure the PDCP Packet Data Unit (PDU) with an appropriate size to perform an Automatic Repeat Request (ARQ) operation, etc. The MAC 4320 and 4340 are connected to several RLC layer devices configured in one terminal, and perform the operation of multiplexing the RLC PDU in the MAC PDU and demultiplexing the RLC PDU from the MAC PDU. The physical layer (PHY) 4325 and 4345 perform channel coding and modulation of high-layer data, make the high-layer data into OFDM symbols, and send the high-layer data to the radio channel, or demodulate the OFDM symbols received through the radio channel, channel decode the OFDM symbols, and send the OFDM symbols to the high layer. In addition, even the physical layers 4325 and 4345 use hybrid automatic repeat request (HARQ) for additional error correction, and can send 1 bit whether the receiving end receives the packet sent from the transmitting end. This is called HARQ ACK / NACK information. Downlink HARQ ACK / NACK information about uplink transmission can be sent through the physical channel of the physical hybrid ARQ indicator channel (PHICH), and uplink HARQ ACK / NACK information about downlink transmission can be sent through the physical channel of the physical uplink control channel (PUCCH) or the physical uplink shared channel (PUSCH).

[0395] As HARQ transmission schemes, there are asynchronous HARQ and synchronous HARQ. Asynchronous HARQ is a scheme in which retransmission timing is not fixed when (re) transmission fails, and synchronous HARQ is a scheme in which retransmission timing is fixed (e.g., 8ms) when (re) transmission fails. In addition, multiple transmissions and receptions can be performed in parallel for downlink and uplink of one terminal, and each transmission is divided into a HARQ process identifier.

[0396] On the other hand, since retransmission timing is not defined in asynchronous HARQ, each time a retransmission is performed, the base station provides information about the HARQ process to which the transmission belongs and whether the transmission is an initial transmission or a retransmission through the physical downlink control channel (PDCCH) physical channel. More specifically, information about the HARQ process to which the transmission belongs is sent through the HARQ process ID field in the PDCCH, and information about the initial transmission or retransmission can be sent through the new data indicator (NDI) bit in the PDCCH. At this time, if the NDI bit does not change relative to the existing value, it means a retransmission, and if the NDI bit changes to other values, it means a new transmission. Therefore, the terminal can receive resource allocation information in the PDCCH sent by the base station in the case of a downlink to understand the details of the corresponding transmission, receive actual data through the physical downlink shared channel (PDSCH) physical channel, and send actual data sent through the physical uplink shared channel (PUSCH) physical channel in the case of an uplink.

[0397] Meanwhile, although not shown in the drawing, a radio resource control (RRC) layer exists in the upper part of the PDCP layers 4310 and 4330 of the terminal and the base station, and the RRC layer can receive and send connection and measurement-related control messages for radio resource control.

[0398] Fig.44 An example of a frame structure of a 5G system using an embodiment of the present disclosure is shown.

[0399] The 5G system may consider scenarios in which it operates at a high frequency to ensure a wide bandwidth for a high transmission speed, and scenarios in which it generates a beam for transmitting data due to difficulties in signal transmission at a high frequency.

[0400] Therefore, when the base station or the transmission reception point (TRP) 4401 communicates with the terminals 4471, 4473, 4475 and 4477 in the cell, communication scenarios using different beams can be considered. That is, in the current exemplary figure, it is assumed that the terminal 1 4471 uses the beam #1 4451 to perform communication, the terminal 2 4473 uses the beam #5 4455 to perform communication, and the terminal 3 4475, the terminal 4 4477 and the terminal 5 4479 use the beam #7 4457 to perform communication.

[0401] In order to measure on which beam the terminals 4471, 4473, 4475, and 4477 communicate with the TRP 4401, an overhead subframe (osf) 4403 exists in time, and in the osf 4403, the base station 4401 can use a different beam for each symbol (or multiple symbols) to transmit a reference signal. In the current exemplary figure, it is assumed that the beams transmitted by the base station 4401 include 12 beams from beam #1 4451 to beam #12 4462, and in the osf 4403, different beams are transmitted while scanning each symbol. In other words, each beam is transmitted to each symbol (for example, beam #1 4451 is transmitted in the first symbol 4431, and beam #2 to beam #12 4452, 4453, 4454, 4455, 4456, 4457, 4458, 4459, 4460, 4461 and 4462 are transmitted in the second to twelfth symbols 4432, 4433, 4434, 4435, 4436, 4437, 4438, 4439, 4440, 4441 and 4442, respectively), so that the terminal can measure OSF 4403 to measure which signal from which beam transmitted in OSF 4403 is the strongest.

[0402] In the current exemplary drawing, it is assumed that a case where a corresponding OSF 4403 is repeated every 25 subframes, and the remaining 24 subframes are data subframes (dsf) 4405 through which general data is transmitted and received.

[0403] Therefore, according to the scheduling of base station 4401, it is assumed that terminal 3 (4475), terminal 4 (4477) and terminal 5 (4479) jointly use beam 7 4457 to communicate with each other (4411), terminal 1 4471 uses beam #1 4451 to perform communication 4413, and terminal 2 4473 uses beam #5 4455 to perform communication 4415.

[0404] The current exemplary figure mainly shows the transmission beam #1 4451 to the transmission beam #12 4462 of the base station 4401, but the reception beam of the terminal for receiving the transmission beam of the base station 4401 (for example, the reception beam #1 to the reception beam #4 4481, 4483, 4485 and 4487 of the terminal 1 4471) can be further considered. In the current exemplary figure, the terminal 1 4471 has four beams 4481, 4483, 4485 and 4487, and beam scanning can be performed to determine which beam has the best reception performance. At this time, if multiple beams can not be used at the same time, one reception beam can be used for each osf 4403, so as to receive multiple osfs 4403 as many as the number of reception beams, so that the transmission beam and the reception beam can be found.

[0405] Fig.45 A beam adjustment method according to an embodiment of the present disclosure is shown.

[0406] Fig.45 Shown as Fig.44 An example of a frame structure is shown, in which downlink transmission beams (DL TX beams) 4501, 4502, 4503 and 4504 transmitted by a base station are scanned in the osf, which is a scenario repeated at a predetermined period.

[0407] The terminal operates in a connection mode and a sleep / idle mode, in which the terminal can connect to a base station to perform communication that can send / receive data between the terminal and the base station, and in a sleep / idle mode, the terminal (which is called paging) monitors only when there is downlink traffic (whether there is no data to send / receive) within a set period and does not send / receive data in the remaining periods. In order to receive paging even in the sleep state, the terminal needs to continuously search for neighboring base stations. If a beam is used as in the present disclosure, the terminal needs to search and select the best base station transmission beam and terminal reception beam even among the selected base stations.

[0408] In this way, if the terminal fails to monitor and determine the base station transmit beam and the terminal receive beam in sleep mode, the terminal can perform measurements on all combinations of the corresponding base stations. For example, in the current scenario, it is assumed that the base station has four TX beams, and even the terminal may have four downlink receive beams (DL RX beams) for the downlink. In this case, the terminal can perform all measurements 4511, 4512, 4513, and 4514 by changing the receive beam of the terminal using each receive beam of the terminal per osf. For measurements 4511, 4512, 4513, and 4514, the terminal can synchronize the downlink according to the synchronization signal from the base station to obtain the timing of each subframe, so that it can be known whether a specific subframe is osf or dsf. The terminal determines whether the downlink reference signal of the base station sent to the TX beam of the base station meets the predetermined condition through measurement processes 4511, 4512, 4513, and 4514. If it is determined that the downlink reference signal meets the predetermined condition, the terminal can regard the corresponding beam as a suitable beam. The terminal can camp on the appropriate beam and then monitor paging from the corresponding beam. Through the above process, the terminal can find the combination of the best TX beam from the base station and the RX beam of the terminal (4551).

[0409] exist Fig.45In the example shown, it can be assumed that TX beam #3 and RX beam #2 are found through process 4551. Then, as in the above process 4551, the terminal no longer updates the measurement using each RX beam of each osf, and can have a predetermined discontinuous reception (DRX) cycle 4525 proposed in the present disclosure, and uses the current best RX beam (RX beam #2 in this example) to measure the current best TX beam (TX beam #3 in this example) (4521, 4523). By doing so, the terminal can determine whether the signal strength / quality measured from the combination of the TX beam and the RX beam found in process 4551 is equal to or greater than a predetermined level (e.g., a first threshold) while reducing power consumption.

[0410] In the above example, for ease of explanation, it is assumed that only one selected RX beam (RX beam #2) is measured. However, in another embodiment, in order to further improve the reliability of reception, it is even possible to consider measuring other adjacent RX beams in addition. That is, the number of downlink receive beams in the downlink receive beam configuration (receive beam width or scan length) can be determined by information related to the number of receive beams supported by the terminal and a combination of predetermined integers pre-set for each frequency band (or the lower value of the two). If the level is determined to be equal to or higher than a predetermined level, it can be determined by an equation using the downlink reference signal strength, the uplink correction factor, and a predetermined constant as inputs. The uplink correction factor can be determined by an equation using the uplink transmission beam configuration capability of the terminal and the power level of the terminal, and the uplink transmission beam configuration capability of the terminal can be defined for each NR band supported by the terminal.

[0411] At the same time, according to an embodiment, the base station may send configuration information for performing measurements according to the DRX cycle to the terminal by broadcasting. Optionally, the base station may send the configuration information to the terminal by a control signal sent to a specific terminal. According to an embodiment, the configuration information may be sent to the terminal together with the reference signal BRS, or may be sent as a separate signal. At this time, examples of configuration information may include the DRX cycle, how many RX beams are used to perform measurements (ie, the RX beam scanning frequency), how many TX beams the base station uses to send BRS, a first threshold for comparing the measured signal strength / quality, etc.

[0412] If the measurement result in process 4553 is equal to or less than a predetermined level, the terminal stops the DRX operation (i.e., process 4553) to find a new combination of the best TX beam and RX beam and performs Rx beam scanning in n consecutive osfs to determine a new DL Tx beam and DL Rx beam. That is, the base station can send a reference signal while each osf changes RX beams 4531, 4532, 4533, and 4534. Each osf of the terminal measures the reference signals of all TX beams (4541, 4542, 4543, 4544) from the terminal to find a new combination of the best TX beam and RX beam (4555). If a predetermined reference or larger beam is found from the measurement results, the terminal returns to the DRX operation (i.e., process 4553), but if any combination of beams does not meet the above conditions, the terminal can search for other base stations or TRP signals to find a suitable combination of beams of the appropriate base station.

[0413] Fig.46 The message flow between the terminal and the base station when the beam adjustment method according to the embodiment of the present disclosure is used is shown.

[0414] exist Fig.46 In the foregoing, for ease of description, it is assumed that the best base station TX beam and terminal RX beam (e.g., TX beam #3, RX beam #2) are found in advance as in steps 4551 and 4553.

[0415] In this case, instead of using all RX beams to measure the reference signal from the base station 4615, the terminal 4610 may use a limited number of RX beams (e.g., two (RX beam #1 and RX beam #2)) for measuring the reference signal from the base station 4615. That is, in step 4620, the terminal 4610 may set the default DL RX beam scanning frequency to 2, and may be set to measure the reference signal from the base station 4615 using RX beam #1 and RX beam #2.

[0416] Therefore, in steps 4631 and 4632, the terminal 4610 can measure the beam reference signal (BRS) from the base station 4615 using the Rx beam #1 and RX beam #2 for the previously measured TX beam #3, as in the assumption. Fig.45 As described in the related part, the terminal can measure the corresponding beam in steps 4633 and 4634 without measuring for each osf according to the predetermined discontinuous reception (DRX) cycle 4630. That is, the terminal can measure the BRS from the base station 4615 using Rx beam #1 and RX beam #2 for TX beam #3 in steps 4633 and 4634 according to the DRX cycle.

[0417] Thereafter, all measurement results of a limited number of RX beams (eg, Rx beam #1 and RX beam #2) may not satisfy a predetermined condition. Therefore, in step 4640, the terminal 4610 may not find a suitable beam.

[0418] Therefore, in step 4645, the terminal 4610 may also additionally measure the number of RX beams by increasing the number of RX beams. At this time, according to an embodiment, the terminal 4610 may perform measurements at a period less than the number of DRX cycles 4630, or perform measurements at continuous osfs. In the current exemplary figure, it is assumed that the number of RX beams is increased to 4 (e.g., RX beam #1, RX beam #2, RX beam #3, and RX beam #4). At this time, according to an embodiment, additional measurements may be performed by increasing the number of TX beams when measuring each RX beam. In the current exemplary figure, the case where measurements are performed is by increasing TX beam reception from one (e.g., TX beam #3) to four (e.g., TX beam #1, TX beam #2, TX beam #3, TX beam #4). Therefore, in steps 4651, 4652, 4653, 4654, 4656, 4657, 4658, 4659, 4661, 4662, 4663, 4664, 4666, 4667, 4668 and 4669, the terminal 4610 can measure the BRS of the TX beams (TX Beam #1, TX Beam #2, RX Beam #3, RX Beam #4) sent by the base station 4615 to each RX beam (RX Beam #1, RX Beam #2, RX Beam #3, RX Beam #4).

[0419] Terminal 4610 measures BRS according to the above process to find the best combination of TX beam and RX beam that meets the predetermined condition. Although not shown in the exemplary drawings, if the best combination of TX beam and RX beam that meets the predetermined condition is not found from the corresponding BS 4615, terminal 4610 can also look for beams of other base stations.

[0420] In the current exemplary figure, in step 4670, it can be assumed that the terminal 4610 finds TX beam #1 and RX beam #3 in the best combination. In this case, in steps 4681 and 4682, the terminal 4610 can again use the reduced number of RX beams (e.g., two RX beams (RX beam #3, RX beam #4) to measure the signal strength / quality of the corresponding TX beam (e.g., TX beam #1). The terminal 4610 can adjust the measurement period by using the DRX cycle 4680 to perform the measurement of the corresponding beam in steps 4683 and 4684, thereby reducing the power consumption of the terminal 4610.

[0421] Fig.47 The flow of the operation of the terminal according to an embodiment of the present disclosure is shown.

[0422] Reference Fig.47 In step 4710, the terminal can measure the reference signal from the base station currently camped or connected according to the current downlink receive beam configuration. In the current exemplary drawings, for ease of explanation, as shown in Fig.45 In step 4553, it is assumed that the terminal has found the best TX beam and RX beam. Therefore, it is assumed that the scenario of performing measurement with a predetermined DRX cycle.

[0423] Thereafter, in step 4720, the terminal may determine whether all reference signal measurement results do not meet the predetermined condition according to the current configuration. For example, the terminal may determine whether the quality of the service beam is less than a preset first threshold Thres 1. If the quality of the service beam is not less than the preset first threshold Thres 1, the terminal may return to step 4710 and perform measurement with a predetermined DRX cycle.

[0424] On the other hand, if the quality of the serving beam is less than the preset first threshold Thres 1, the terminal may perform additional measurements by adjusting the receiving beam configuration and direction in step 4730. The receiving beam configuration includes a method of performing additional measurements by increasing the number of receiving beams.

[0425] At this time, in step 4740, the terminal may perform measurement with a period less than the number of DRX cycles, or perform measurement on continuous OSF to find the best combination of TX beam and RX beam. In step 4750, the terminal may determine whether the best combination of TX beam and RX beam is found. For example, the terminal may determine the modified quality of the serving beam, that is, whether the reception quality of the measured beam is less than the preset second threshold Thres 2. If the reception quality of the measured beam is not less than the second threshold Thres 2, the terminal may determine the reception quality of the measured beam as the best combination of TX beam and RX beam. The terminal returns to step 4710 and may perform measurement using a predetermined DRX cycle.

[0426] If the beam combination of the base station that meets the predetermined condition is not found through the above process, the terminal can start looking for beams of other base stations in step 4760.

[0427] Fig.48 A configuration of a terminal according to an embodiment of the present disclosure is shown.

[0428] Reference Fig.48 According to an embodiment of the present disclosure, the terminal may include a transceiver and a controller 4840. The terminal may also include a memory 4830. At this time, the transceiver may be a radio frequency (RF) processor 4810. In an embodiment, the transceiver may include an RF processor 4810 and a baseband processor 4820.

[0429] The RF processor 4810 is used to transmit / receive signals through a radio channel, such as frequency band conversion and signal amplification. That is, the RF processor 4810 can up-convert the baseband signal provided from the baseband processor 4820 into an RF band signal, then transmit the RF band signal through an antenna, and down-convert the RF band signal received through the antenna to a baseband signal. For example, the RF processor 4810 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc. Fig.48 Only one antenna is shown, but the terminal may include multiple antennas. In addition, the RF processor 4810 may include multiple RF chains. In addition, the RF processor 4810 may perform beamforming. For beamforming, the RF processor 4810 may adjust the phase and size of each signal sent and received by multiple antennas or antenna elements. In addition, the RF processor 4810 may perform MIMO and may receive multiple layers when performing MIMO operations. The RF processor 4810 may perform receive beam scanning by appropriately configuring multiple antennas or antenna elements under the control of the controller 4840, or adjust the direction and beam width of the receive beam so that the receive beam resonates with the transmit beam.

[0430] The baseband processor 4820 performs the conversion function between the baseband signal and the bit string according to the physical layer standard of the system. For example, when sending data, the baseband processor 4820 generates complex symbols by encoding and modulating the transmitted bit string. In addition, when receiving data, the baseband processor 4820 can recover the received bit string by demodulating and decoding the baseband signal provided from the RF processor 4810. For example, according to the orthogonal frequency division multiplexing (OFDM) scheme, when sending data, the baseband processor 4820 can generate complex symbols by encoding and modulating the transmitted bit string, mapping the complex symbols to subcarriers, and then configuring OFDM symbols by inverse fast Fourier transform (IFFT) operation and cyclic prefix (CP) insertion. In addition, when receiving data, the baseband processor 4820 can segment the baseband signal provided from the RF processor 1410 in OFDM symbol units, recover the signal mapped to the subcarrier by fast Fourier transform (FFT) operation, and then recover the bit string received by modulation and decoding.

[0431] As described above, the baseband processor 4820 and the RF processor 4810 can send and receive signals. Therefore, the baseband processor 4820 and the RF processor 4810 can be referred to as a transmitter, a receiver, a transceiver, or a communicator. In addition, at least one of the baseband processor 4820 and the RF processor 4810 may include different communication modules to process signals in different frequency bands. Different frequency bands may include ultra-high frequency (SHF) (e.g., 0.5 GHz, 5 GHz, etc.) bands, millimeter wave (e.g., 60 GHz, etc.) bands.

[0432] The memory 4830 may store data such as basic programs, application programs, and configuration information for operation of the terminal. The memory 4830 may provide the stored data according to a request of the controller 4840.

[0433] The controller 4840 can control the overall operation of the terminal to perform any one of the operations of the above-mentioned embodiments. For example, the controller 4840 can send / receive signals through the baseband processor 4820 and the RF processor 4810. In addition, the controller 4840 can record data in the memory 4830 and read data from the memory 4830. For this purpose, the controller 4840 may include a circuit, a dedicated circuit, or at least one processor. For example, the controller 4840 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls high layers such as applications. In addition, the operation of the terminal can be implemented by including a memory device storing corresponding program codes in any component of the terminal. That is, the controller 4840 can perform the above-mentioned operations by reading and executing the program codes stored in the memory device by a processor, a central processing unit (CPU), etc. The controller 1240 can be electrically connected to other components, for example, the transceiver 1210. According to an embodiment of the present disclosure, the controller 4840 includes a multi-connection processor 4845 that performs processing to be operated in a multi-connection mode. For example, the controller 4840 can control the terminal to perform Fig.47 The process shown in the operation of the terminal shown in .

[0434] According to an embodiment of the present disclosure, the controller 4840 of the terminal can instruct the RF processor 4810 and the baseband processor 4820 of the terminal to measure different transmit beams sent by a specific base station using different beams of the terminal, and find the best transmit beam and receive beam, and then use the scheme proposed in the present disclosure to instruct the measurement of using specific transmit beams and receive beams in a predetermined DRX cycle.

[0435] The method according to the embodiments described in the claims or the specification of the present disclosure may be implemented in hardware, software, or a combination of hardware and software.

[0436] When the method is implemented in software, a computer-readable storage medium storing at least one program (software module) may be provided. The at least one program stored in the computer-readable storage medium is configured to be executed by at least one processor in an electronic device. The at least one program includes instructions that allow the electronic device to perform the method according to the embodiments described in the claims or description of the present disclosure.

[0437] The program (software module, software) can be stored in a random access memory, a non-volatile memory including flash memory, a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic disk storage device, a compact disk-ROM (CD-ROM), a digital versatile disk (DVD) or other type of optical storage device, and a magnetic tape cartridge. Alternatively, the program can be stored in a memory configured by a combination of some or all of the memories. In addition, each memory can also include multiple.

[0438] In addition, the program may be stored in an attachable storage device that can be accessed through a communication network (such as the Internet, an intranet, a local area network (LAN), a wide LAN (WLAN), and a storage area network (SAN), or a communication network configured in combination thereof). The storage device may access the apparatus for executing the embodiments of the present disclosure through an external port. In addition, a separate storage device on the communication network may also access the apparatus for executing the embodiments of the present disclosure.

[0439] In the detailed embodiments of the present disclosure, according to the detailed embodiments as described above, the components included in the present disclosure are expressed in the singular or plural. However, the singular or plural expressions are selected to meet the situation proposed for the convenience of explanation, and the present disclosure is not limited to a single component or multiple components, and even if the component is expressed in the plural, the component can also be configured in the singular, or even if the component is expressed in the singular, the component can also be configured in the plural.

[0440] Although exemplary embodiments of the present disclosure have been disclosed for illustrative purposes, various modifications, additions and substitutions may be made without departing from the scope and spirit of the present disclosure disclosed in the appended claims. Therefore, the scope of the present disclosure should not be interpreted as limited to the described embodiments, but is defined by the appended claims and their equivalents.

[0441] Hereinafter, if it is determined that the detailed description of known technologies related to the present disclosure may obscure the gist of the present disclosure, the detailed description thereof will be omitted. Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0442] The present disclosure relates to a method and apparatus for selecting a network for performing wireless mobile communication by a terminal including an NR communication device and an LTE communication device capable of communicating with the NR network and the LTE network, and the terminal operation may include the following steps: applying a first method to obtain a public land mobile network (PLMN) identifier in the LTE network; applying a second method to obtain a PLMN identifier in the NR network; selecting a PLMN based on the obtained PLMN identifier; and initiating a mobile communication service in the selected PLMN.

[0443] The first method is to detect a carrier by scanning all RF channels and obtain a PLMN identifier by receiving system information of a cell having the strongest signal strength among cells of the detected carrier.

[0444] The second method is to detect the carrier by scanning the RF channel that meets condition A in the downlink beam of the detected carrier and obtaining the system information of the downlink beam that meets condition B to obtain the PLMN identifier.

[0445] In addition, the RF channel of LTE is configured by a frequency domain having a first bandwidth and is specified by a predetermined integer called EARFCN. In addition, the RF channel of NR is configured by a frequency domain having a second bandwidth and is specified by a predetermined integer called NARFCN.

[0446] The RF channel satisfying condition A means an RF channel having a frequency lower than a predetermined value or an RF channel having a frequency band for performing an idle mode operation among RF channels that can be scanned by the terminal.

[0447] A downlink beam satisfying condition B indicates a beam whose reference signal strength of the downlink beam is equal to or greater than a predetermined value or which can receive predetermined system information of the downlink beam. At this time, the system information may not be system information accommodating a PLMN identifier, but may be system information transmitted simultaneously with the beam reference signal, that is, system information transmitted through the PBCH.

[0448] Fig.49 A structure of a next generation mobile communication system according to an embodiment of the present disclosure is shown.

[0449] Reference Fig.49As shown in the figure, the radio access network of the next generation mobile communication system includes a next generation base station (new radio node B (NR NB)) 4910 and a next generation core network (new radio core network (NR CN), access and mobility management function (AMF), user plane function (UPF), session management function (SMF), etc.) 4920. The user terminal (new radio user equipment (NR UE) or mobile station, terminal, UE) 4930 can be connected to an external network via the NR NB 4910 and the NR CN 4920.

[0450] At the same time, Fig.49 In the embodiment, NR NB 4910 may correspond to a base station (evolved Node B (eNB)) 4940 of an existing LTE system. NR NB 4910 is connected to NR UE 4930 via a radio channel and may provide services superior to those of the existing Node B (base station) 4940. In the next generation mobile communication system, since all user services are served through a shared channel, a device for collecting status information (such as the buffer status of UE 4930, the available transmission power status, and the channel status) is required to perform scheduling. NR NB 4910 may play the role of the device. One NR NB 4910 may typically control multiple cells.

[0451] In order to achieve ultra-high-speed data transmission compared with the existing LTE, the next-generation mobile communication system may have a bandwidth equal to or greater than the maximum bandwidth of the existing LTE, and may additionally apply a beamforming technology using orthogonal frequency division multiplexing (OFDM) as a radio access technology. In addition, an adaptive modulation & coding (hereinafter referred to as AMC) scheme for determining a modulation scheme and a channel coding rate according to the channel state of the terminal 4930 may be applied. NR CN 4920 may perform functions such as mobility support, bearer establishment, QoS establishment, and the like. NR CN 4920 is a device for performing various control functions of the terminal 4930 and a mobility management function, and may be connected to a plurality of base stations 4910.

[0452] In addition, the next generation mobile communication system can even interact with the existing LTE system, and the NR CN 4920 can be connected to the MME 4950 through a network interface according to an embodiment. The MME 4950 is connected to the eNB 4940 which is an existing base station.

[0453] Fig.50 Beam scanning of an NR system according to an embodiment of the present disclosure is shown.

[0454] NR is designed to support higher data rates than existing LTE. As a method for increasing the data transmission speed in NR, a method of transmitting signals using a wide frequency band existing in a 6GHz or higher frequency band is considered. That is, it is considered to increase the transmission rate by using a millimeter wave (mmWave) band like a 28GHz band or a 60GHz band. Since the frequency band considered by mmWave is relatively large in the signal attenuation amplitude per distance, it is necessary to use a directional beam-based transmission generated by multiple antennas to ensure coverage. Transmission based on directional beams has the problem that it is difficult to send or receive signals at a location where a beam is not formed, and a technology called beam scanning is used to overcome the above problem. Beam scanning is a technology that allows a transmitting device to transmit a directional beam while sequentially scanning or rotating a directional beam with a constant beam width and allows a receiving device to receive the beam within the beam reach distance of the transmitting device.

[0455] For example, a transmission reception point (TRP) 5005 (which is a device for transmitting and receiving radio signals in a network, which may be a 5G NB, and a device connected to the 5G NB) may cover beams in all directions in a predetermined period (e.g., t1 to t11), wherein a directional beam having a predetermined width is transmitted in a predetermined direction at any time t1, and a directional beam having the same width is transmitted in different directions at time t2. As a result, for example, a downlink signal transmitted by the base station 5005 may reach the first terminal 5015 at t9 and the second terminal 5010 at t4.

[0456] Beam scanning is mainly used when the base station 5005 does not know the direction of the directional beam to be applied to the terminals 5010 and 5015. A common overhead signal to be transmitted to the idle state terminal can be transmitted through beam scanning.

[0457] In order to improve the efficiency of the beam, not only the transmission directional beam but also the reception directional beam can be used. If the reception directional beam is used, the directivity / direction of the transmission beam and the directivity / direction of the reception beam need to be tuned with each other.

[0458] For example, even if the terminal is located in the area of ​​the transmission beam, the terminal cannot receive the transmission beam unless the directivity of the terminal's reception beam is tuned with the directivity of the base station's transmission beam, as shown in 5020. On the other hand, as shown in 5025, if the directivity of the base station's transmission beam and the directivity of the terminal's reception beam are tuned with each other, the terminal can send and receive data with much higher efficiency than when the terminal does not have a reception beam.

[0459] In order to find a receiving beam that is synchronized with the transmitting beam, the receiving device searches for a receiving beam that provides the best reception quality by applying different receiving beams to the same transmitting beam. This process is called receiving beam scanning.

[0460] Fig.51 The subframe structure of the NR system according to an embodiment of the present disclosure is shown.

[0461] In a mobile communication system using directional beams, analog beams or hybrid beams, a common overhead signal is subjected to beam scanning transmission in a specific subframe, while in another subframe, a directional beam in a unidirectional direction is used to transmit / receive user data to / from a specific terminal.

[0462] An overhead subframe (OSF) 5105, which is a subframe in which an overhead signal is received, may be repeatedly transmitted in a predetermined period 5110. One subframe consists of a plurality of symbols, and one directional beam for each symbol may be transmitted in the OSF. For example, the first symbol 5115 of the OSF may correspond to t1, the second symbol 5120 may correspond to t2, and the eleventh symbol 5125 may correspond to t11, and a directional beam (or analog beam) having the same beam width for each symbol but covering other areas and having a directivity setting in different directions may be transmitted. On the other hand, the transmission of a beam may have the same meaning as the transmission of a reference signal using the corresponding beam.

[0463] The following overhead signals can be sent for each symbol of OSF 5105: signals used to establish downlink synchronization (such as the primary synchronization signal (PSS) and the secondary synchronization signal (SSS)); the beam reference signal (BRS) capable of measuring the received signal strength or received signal quality of each beam; system information, master information block (MIB) or physical broadcast channel (PBCH); PBCH may include information required for the terminal to access the system, such as the bandwidth of the downlink beam, the system frame number, etc.

[0464] For reference, the PLMN identifier may be broadcast on a channel other than the MIB.

[0465] In a subframe other than the periodically transmitted OSF 5105, the same beam may be transmitted over a plurality of consecutive symbols, and user data for a specific connection terminal may be transmitted through the beam. Hereinafter, this subframe may be referred to as a data subframe (DSF) 5130.

[0466] Meanwhile, in order to receive the desired service in the mobile communication system, the terminal performs a process of selecting an operator or a public land mobile network (PLMN), which is referred to as a PLMN selection process. If the terminal has multiple radio access technologies (RATs), the terminal obtains the PLMN identifiers of the available operators for each radio access technology and selects one of the available PLMNs. Terminals with LTE and NR may also perform a PLMN selection process, and the terminal may obtain system information in a predetermined cell of the LTE frequency to obtain the PLMN identifier contained in the system information, and obtain system information from a predetermined downlink beam of the NR frequency to obtain the PLMN identifier included in the system information. At this time, the terminal applies a differential search operation to LTE and NR to improve the efficiency of the PLMN selection process.

[0467] Fig.52 The overall operation according to the embodiment of the present disclosure is shown.

[0468] In a mobile communication system including a terminal 5210 capable of communicating with both an NR network and an LTE network, one or more LTE carriers 5221, 5222, and 5223, and one or more NR carriers 5224, 5225, and 5226, a PLMN selection process may be initiated. The PLMN selection is a process mainly performed when the terminal 5210 is powered on again, identifying an operator providing a mobile communication service in a corresponding area at a corresponding time, and selecting one of the operators to select to receive the mobile communication service.

[0469] The radio access technology of LTE is called E-UTRA, and the radio access technology of NR is called NR-UTRA. In the present disclosure, LTE, E-UTRA, NR and NR-UTRA may be used interchangeably.

[0470] The terminal 5210 that initiates the PLMN selection process can scan the radio frequency (RF) channel to determine the accessible operator in the corresponding area at the corresponding time. At this time, the terminal 5210 can perform a full scan 5230 for LTE and a partial scan 5250 for NR. Perform RF channel scanning based on frequency band. Performing a full scan on any frequency band means that all RF channels of the corresponding frequency band are completely scanned in all directions. Partial scanning means that the RF channels of the corresponding frequency band are scanned only in certain directions. In other words, in the full scan, the terminal 5210 performs a receive beam scan on each RF channel, and in the partial scan, the terminal 5210 does not perform a receive beam scan on each RF channel. In addition, the terminal 5210 can perform RF channel scanning (full scan) on all frequency bands supported by the terminal 5210, or can perform RF channel scanning (partial scan) only on certain frequency bands that meet predetermined conditions. This will be described in more detail.

[0471] In step 5231, the terminal 5210 may perform RF channel scanning from the frequency band most likely to be served in the corresponding area among the LTE frequency bands supported by the terminal 5210. As a result of the RF channel scanning, if an LTE carrier (e.g., a first carrier (carrier 1)) is detected in step 5232, then in step 5233, the terminal 5210 may receive predetermined system information in the strongest cell of the corresponding carrier (the cell with the strongest reception strength of the cell reference signal CRS). The system information includes the operator information of the cell, i.e., the PLMN identifier (e.g., PLMN x). The terminal 5210 performs RF channel scanning on all LTE frequencies supported by the terminal to identify available PLMNs. That is, if the terminal 5210 performs RF channel scanning in step 5234 and detects a second carrier (carrier 2) in step 5235, then in step 5236, the terminal 5210 may receive system information including the PLMN identifier (e.g., PLMN y) in the strongest cell of the corresponding carrier. If the terminal 5210 performs RF channel scanning in step 5237 and detects the third carrier (carrier 3) in step 5238, the terminal 5210 may receive system information including a PLMN identifier (e.g., PLMN y) in the strongest cell of the corresponding carrier in step 5239. In step 5240, the terminal 5210 may perform RF channel scanning on all remaining RF channels.

[0472] In step 5250, the terminal 5210 may perform partial scanning on NR. That is, in step 5251, the terminal 5210 may perform RF channel scanning only on some frequency bands that meet predetermined conditions among all NR frequency bands supported by the terminal 5210. Instead of performing downlink reception beam scanning to find a downlink reception beam that resonates with the downlink transmission beam when performing RF channel scanning, the downlink reception beam may perform RF channel scanning by forming it to a predetermined beam width in a predetermined direction.

[0473] In step 5252, when the terminal 5210 detects an NR carrier (e.g., the fourth carrier (carrier 4)), in step 5253, the terminal 5210 may select a good DL beam that satisfies a predetermined condition in the downlink beam of the corresponding carrier to receive system information. The system information includes the operator information of the cell, i.e., a PLMN identifier (e.g., PLMN w). The downlink beam that satisfies the predetermined condition may be, for example, a downlink beam having a reception strength of a beam reference signal exceeding a predetermined reference. If the terminal 5210 performs NR RF channel in step 5254 and detects the fifth carrier (carrier 5) in step 5255, in step 5256, the terminal 5210 may select a good DL beam that satisfies a predetermined condition in the downlink beam of the corresponding carrier to receive system information including a PLMN identifier (e.g., PLMN v). At the same time, as described above, the terminal 5210 may perform RF channel scanning only on some of all NR bands supported by the terminal 5210 that meet the predetermined condition. Next, as in step 5257, terminal 5210 can skip some NR RF scans.

[0474] Meanwhile, the terminal 5210 that has identified at least one available PLMN may proceed to step 5260 to select a PLMN. In step 5270, the terminal 5210 may perform a registration process in the selected PLMN and receive a mobile communication service.

[0475] Fig.53 The operation of the terminal according to an embodiment of the present disclosure is illustrated.

[0476] Reference Fig.53 In step 5310, the terminal may instruct the non-access stratum (NAS) to search for a PLMN available to the radio access device. The above operation may be performed in a specific event, for example, when the terminal is powered on or when the terminal re-enters the service area.

[0477] In step 5320, the radio access device of the terminal (e.g., an E-UTRA radio access device) may scan the RF channels of the E-UTRA band. When selecting the E-UTRA band to be scanned, the terminal may consider the capabilities of the terminal, e.g., the E-UTRA bands supported by the terminal, and may also consider information acquired during the previous same process.

[0478] For any E-UTRA band, the terminal can identify the E-UTRA carrier of the E-UTRA band by RF channel scanning. RF channel scanning is a process of sequentially checking RF channels to determine whether a carrier exists in the corresponding channel. The size of the RF channel of E-UTRA is 100KHz and is formed sequentially from the lowest frequency to the highest frequency of any band and can be specified by an integer called EARFCN ranging from 0 to 262134.

[0479] In step 5330, the terminal identifies a cell having the best reception status among the cells detected in the identified carrier, and receives predetermined system information of the corresponding cell. The PLMN identifier of the cell may be stored in the predetermined system information.

[0480] In step 5340, the access device of the terminal sends the acquired PLMN identifier to the non-access layer.

[0481] At this time, in steps 5320 to 5340, the terminal may be executed on all E-UTRA bands supported by the terminal until the terminal instructs the non-access layer to stop operating.

[0482] Steps 5320 to 5340 are a process for the terminal to determine which PLMN exists in E-UTRA. Steps 5350 to 5370 described later may be performed in parallel with steps 5320 to 5340, or after steps 5320 to 5340 are completed. Steps 5350 to 5370 are a process for determining which PLMN exists in NR-UTRA.

[0483] In step 5350, the NR-UTRA device of the terminal may scan the RF channel of the NR-UTRA band that satisfies condition A. The frequency band that satisfies the predetermined condition A may represent, for example, an NR-UTRA band that allows idle mode operation among the NR-UTRA bands supported by the terminal. At this time, information related to whether the idle mode operation is allowed may be pre-stored in a storage device of the terminal.

[0484] According to this embodiment, when scanning all RF channels of the NR-UTRA band, the terminal can fix and scan the downlink reception beam in a predetermined direction instead of scanning the downlink reception beam. This is because even if the terminal fixes the downlink reception beam in one direction, a carrier capable of providing seamless coverage can receive a signal from at least one TRP.

[0485] The size of the RF channel of NR-UTRA is larger than that of E-UTRA, for example, 500KHz. At this time, NR-UTRA is specified by an integer called NRFCN and can have the same range as EARFCN (range 0 to 262134). Therefore, the RF channel of E-UTRA and the RF channel of NR-UTRA can be specified by the same signaling parameter or information element (IE) and can be signaled to the same IE in the RRC control message.

[0486] In step 5360, the terminal may identify a downlink beam satisfying condition B among the downlink beams of the identified carrier, and may receive predetermined system information in a predetermined frequency / time domain of the corresponding beam. The PLMN identifier of the cell may be stored in the predetermined system information. According to an embodiment, the downlink beam satisfying condition B may represent a downlink beam that can successfully receive the predetermined system information from a downlink beam having a reception strength of a beam reference signal higher than a predetermined reference value or a corresponding downlink beam without an error. The predetermined system information may be system information including a PLMN identifier or system information transmitted in the same time domain or the same symbol as the beam reference signal of the corresponding beam. For example, a downlink beam satisfying the above condition B may represent a downlink beam that can receive system information (e.g., system information transmitted through PBCH) that does not include a PLMN identifier. That is, the terminal may confirm whether the downlink beam is a downlink beam that can receive system information that does not include a PLMN identifier, and then receive system information including a PLMN identifier in the corresponding downlink beam if possible.

[0487] In step 5370, the access device of the terminal may send the acquired PLMN identifier to the non-access layer.

[0488] According to an embodiment, steps 5340 to 5360 may be performed for all NR-UTRA bands that satisfy condition A and are supported by the terminal at the same time until the non-access layer performs an instruction to stop the operation. In addition, according to an embodiment, the NR-UTRA frequency channel that satisfies condition A may represent the remaining channels when the terminal has not yet scanned a channel that can read system information. For example, if the terminal performs a channel scan from a lower frequency (or higher frequency) in the RF channel of the NR-UTRA band, and if the terminal may not read the system information in the scanned channel, the terminal may perform a scan of the next RF channel. However, if the terminal can scan the system information in the scanned channel, the terminal may stop scanning the NR-UTRA frequency channel.

[0489] In step 5370, the non-access stratum of the terminal may select one of the PLMNs reported by the access device. The terminal may select the PLMN based on a PLMN preference list stored in a storage device.

[0490] In step 5390, the non-access layer of the terminal may inform the access device of the identifier and radio access technology of the selected PLMN. If the indicated radio access technology is E-UTRA, the access device of the terminal may camp on the cell of the selected PLMN, and if the indicated radio access technology is NR-UTRA, camp on the downlink beam of the selected PLMN. Camping on a cell or beam means receiving system information from the corresponding cell or beam and monitoring whether a paging message is received.

[0491] Fig.54 A configuration of a terminal according to an embodiment of the present disclosure is shown.

[0492] Reference Fig.54 According to an embodiment of the present disclosure, a terminal may include a transceiver and a controller 5440. The terminal may further include a memory 5430. At this time, the transceiver may be a radio frequency (RF) processor 5410. In an embodiment, the transceiver may include an RF processor 5410 and a baseband processor 5420.

[0493] The RF processor 5410 is used to transmit / receive signals through a radio channel, such as frequency band conversion and signal amplification. That is, the RF processor 5410 can up-convert the baseband signal provided from the baseband processor 5420 into an RF band signal, and then transmit the RF band signal through an antenna, and down-convert the RF band signal received through the antenna into a baseband signal. For example, the RF processor 5410 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc. Fig.54 Only one antenna is shown, but the terminal may include multiple antennas. In addition, the RF processor 5410 may include multiple RF chains. In addition, the RF processor 5410 may perform beamforming. For beamforming, the RF processor 5410 may adjust the phase and size of each signal sent and received by multiple antennas or antenna elements. In addition, the RF processor may perform MIMO and may receive multiple layers when performing MIMO operations. The RF processor 5410 may perform receive beam scanning by appropriately configuring multiple antennas or antenna elements under the control of the controller 5440, or adjust the direction and beam width of the receive beam so that the receive beam resonates with the transmit beam.

[0494] The baseband processor 5420 performs a conversion function between a baseband signal and a bit string according to the physical layer standard of the system. For example, when sending data, the baseband processor 5420 generates a complex symbol by encoding and modulating the transmitted bit string. In addition, when receiving data, the baseband processor 5420 can recover the received bit string by demodulating and decoding the baseband signal provided from the RF processor 5410. For example, according to the orthogonal frequency division multiplexing (OFDM) scheme, when sending data, the baseband processor 5420 can generate a complex symbol by encoding and modulating the transmitted bit string, mapping the complex symbol to a subcarrier, and then configuring the OFDM symbol by an inverse fast Fourier transform (IFFT) operation and a cyclic prefix (CP) insertion. In addition, when receiving data, the baseband processor 5420 can segment the baseband signal provided from the RF processor 5410 in OFDM symbol units, recover the signal mapped to the subcarrier by a fast Fourier transform (FFT) operation, and then recover the bit string received by modulation and decoding.

[0495] As described above, the baseband processor 5420 and the RF processor 5410 can send and receive signals. Therefore, the baseband processor 5420 and the RF processor 5120 can be referred to as a transmitter, a receiver, a transceiver, or a communicator. In addition, at least one of the baseband processor 5420 and the RF processor 5410 may include multiple communication modules to support a variety of different radio access technologies. In addition, at least one of the baseband processor 5420 and the RF processor 5410 may include different communication modules to process signals in different frequency bands. For example, different radio access technologies may include LTE networks, NR networks, and the like. In addition, different frequency bands may include ultra-high frequency (SHF) (e.g., 2.5 GHz, 5 GHz, etc.) bands, millimeter waves (e.g., 60 GHz, etc.),.

[0496] The memory 5430 stores data such as a basic program, application programs, and configuration information for operation of the terminal. The memory 5430 may provide the stored data according to a request of the controller 5440.

[0497] The controller 5440 can control the overall operation of the terminal to perform any one of the operations of the above-mentioned embodiments. For example, the controller 5440 can send / receive signals through the baseband processor 5420 and the RF processor 5410. In addition, the controller 5440 can record data in the memory 5430 and read data from the memory 5430. For this purpose, the controller 5440 may include a circuit, a dedicated circuit, or at least one processor. For example, the controller 5440 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls a high layer such as an application. In addition, the operation of the terminal can be implemented by including a memory device storing corresponding program codes in any component of the terminal. That is, the controller 5440 can perform the above-mentioned operations by reading and executing the program codes stored in the memory device by a processor, a central processing unit (CPU), etc. In addition, according to an embodiment of the present disclosure, the controller 5440 may include a multi-connection processor 5445 to perform processing to be operated in a multi-connection mode. The controller 5440 may be electrically connected to other components, for example, a transceiver 5410.

[0498] Fig.55 The configuration of a base station according to an embodiment of the present disclosure is shown.

[0499] Reference Fig.55 , the base station according to one embodiment of the present disclosure may include a transceiver and a controller 5540. In addition, the base station may further include a backhaul communication interface 5550 and a memory 5530. At this time, the transceiver may be a radio frequency (RF) processor 5510. According to an embodiment, the transceiver may include an RF processor 5510 and a baseband processor 5520.

[0500] The RF processor 5510 is used to transmit / receive signals through a radio channel, such as frequency band conversion and signal amplification. That is, the RF processor 5510 up-converts the baseband signal provided by the baseband processor 5520 into an RF band signal, then transmits the baseband signal through an antenna, and down-converts the RF band signal received through the antenna into a baseband signal. For example, the RF processor 5510 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc. Fig.55 Only one antenna is shown, but the base station may include multiple antennas. In addition, the RF processor 5510 may include multiple RF chains. In addition, the RF processor 5510 may perform beamforming. For beamforming, the RF processor 5510 may adjust the phase and size of each signal sent and received through multiple antennas or antenna elements. The RF processor 5510 may perform downlink MIMO operations by sending one or more layers.

[0501] The baseband processor 5520 performs a conversion function between a baseband signal and a bit string according to the physical layer standard of the first radio access technology. For example, when sending data, the baseband processor 5520 generates a complex symbol by encoding and modulating the transmitted bit string. In addition, when receiving data, the baseband processor 5520 recovers the received bit string by demodulating and decoding the baseband signal provided from the RF processor 5510. For example, according to the OFDM scheme, when sending data, the baseband processor 5520 can generate a complex symbol by encoding and modulating the transmitted bit string, mapping the complex symbol to a subcarrier, and then configuring the OFDM symbol through IFFT operation and CP insertion. In addition, when receiving data, the baseband processor 5520 divides the baseband signal provided from the RF processor 5510 in OFDM symbol units, and recovers the signal mapped to the subcarrier through FFT operation, and then recovers the received bit string through modulation and decoding.

[0502] The baseband processor 5520 and the RF processor 5510 can send and receive signals as described above. Therefore, the baseband processor 5520 and the RF processor 5510 can be referred to as a transmitter, a receiver, a transceiver, a communication interface, or a wireless communication interface. In addition, at least one of the baseband processor 5520 and the RF processor 5510 may include multiple communication modules to support a variety of different radio access technologies. In addition, at least one of the baseband processor 5520 and the RF processor 5510 may include different communication modules to process signals in different frequency bands. For example, different radio access technologies may include wireless LANs (e.g., IEEE 802.11, etc.), cellular networks (e.g., LTE, etc.), etc. In addition, different frequency bands may include ultra-high frequency (SHF) (e.g., 2.5 GHz, 5 GHz, etc.) bands, millimeter wave (e.g., 60 GHz, etc.) bands.

[0503] The communication interface 5550 provides an interface for performing communications with other nodes within the network.

[0504] The memory 5530 stores data such as basic programs, applications, and setting information for base station operation. Specifically, the memory 5530 can store information about the bearer assigned to the accessed terminal, measurement results reported from the accessed terminal, etc. In addition, the memory 5530 can store information as a determination standard for providing multiple connections to the terminal or stopping multiple connections to the terminal. The memory 5530 can provide the stored data according to the request of the controller 5540.

[0505] The controller 5540 can control the overall operation of the base station to perform any one of the operations of the above-mentioned embodiments. For example, the controller 5540 can send / receive signals through the baseband processor 5520 and the RF processor 5510 or the backhaul communication interface 5550. In addition, the controller 5540 can record data in the memory 5530 and read data from the memory 5530. For this purpose, the controller 5540 may include a circuit, a dedicated circuit, or at least one processor. For example, the controller 5540 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls a high layer such as an application. In addition, the operation of the base station can be implemented by including a memory device storing corresponding program codes in any component of the terminal. That is, the controller 5540 can perform the above-mentioned operations by reading and executing the program codes stored in the memory device by a processor, a central processing unit (CPU), etc. In addition, according to an embodiment of the present disclosure, the controller 5540 may include a multi-connection processor 5545 that performs processing to be operated in a multi-connection mode. The controller 5540 may be electrically connected to other components, such as a transceiver 5510.

[0506] The embodiments of the present disclosure disclosed in this specification and the accompanying drawings have been provided to easily describe and help understand the described content, and do not limit the scope of the present disclosure. It is obvious to those skilled in the art that, in addition to the embodiments disclosed herein, various modifications can be made without departing from the scope of the present disclosure.

[0507] Although the present disclosure has been described with exemplary embodiments, various changes and modifications may be suggested to one skilled in the art. The present disclosure is intended to encompass such changes and modifications as fall within the scope of the appended claims.

Claims

1. A method performed by a base station in a wireless communication system, the method include: receiving a downlink DL packet from a next generation core network NGCN, the DL packet including information for identifying a flow-based quality of service QoS; identifying whether there is a DRB to which the flow is mapped among at least one established data radio bearer DRB, wherein the mapping of the flow to the DRB is based on information for identifying a flow-based QoS; In the case that the DRB to which the flow is mapped does not exist in at least one established data radio bearer DRB, establishing the DRB; sending a DL packet to the terminal through the DRB, the DL packet including information for identifying a flow-based QoS and an indication associated with reflective QoS, wherein the flow-to-DRB mapping of the DL packet is applied to the flow-to-DRB mapping of the UL packet based on the indication associated with reflective QoS; as well as An uplink UL packet is received from the terminal through the DRB, the UL packet being associated with the flow.

2. The method according to claim 1, further comprising: include: In a case where the DRB to which the flow is mapped exists in the at least one established DRB, sending a DL packet to the terminal through the at least one established DRB, and The method further comprises: sending a control message including information about the mapping between flows and DRBs to the terminal, Here, the UL packet is received from the terminal through the DRB identified based on the information about the mapping.

3. The method according to claim 1, further comprising: include: receiving, in a case where there is no other DRB to which other flows associated with other UL packets are mapped among the at least one established DRB, other UL packets from the terminal through a default DRB among the at least one established DRB, wherein the other UL packets include information for identifying other QoS based on other flows; and Establish with the terminal the other DRB to which the other flows associated with the other UL packets are mapped.

4. The method according to claim 1, in, Identifying whether there is a DRB to which the flow is mapped is performed by an upper layer of a Packet Data Convergence Protocol PDCP layer.

5. A method performed by a terminal in a wireless communication system, the method include: In the case that there is no DRB to which the flow associated with the downlink DL packet is mapped among the at least one established data radio bearer DRB, establishing the DRB to which the flow associated with the DL packet is mapped; receiving a DL packet from a base station through a DRB, the DL packet including information for identifying a flow-based QoS and an indication associated with reflective QoS, wherein the flow-to-DRB mapping of the DL packet is applied to the flow-to-DRB mapping of the UL packet based on the indication associated with reflective QoS; and An uplink UL packet is sent to the base station through the DRB, the UL packet being associated with the flow.

6. The method according to claim 5, further comprising: include: In a case where the DRB to which the flow is mapped exists in the at least one established DRB, receiving a DL packet from the base station through the at least one established DRB, and The method further comprises: receiving a control message including information about mapping between flows and DRBs from a base station, and The UL packet is transmitted to the base station through the DRB identified based on the information about the mapping.

7. The method according to claim 5, further comprising: include: In the absence of other DRBs to which other flows associated with the other UL packets are mapped, sending other UL packets to the base station through a default DRB in the at least one established DRB, wherein the other UL packets include information for identifying other QoS based on other flows, and The other DRB to which the other flow associated with the other UL packet is mapped is established with the base station.

8. The method according to claim 7, further comprising: include: An upper layer of the Packet Data Convergence Protocol PDCP layer identifies whether there are other DRBs to which other flows associated with other UL packets are mapped.

9. A base station in a wireless communication system, include: Transceiver; as well as A controller is coupled to the transceiver and is configured to: receiving a downlink DL packet from a next generation core network NGCN, the DL packet including information for identifying a flow-based quality of service QoS; identifying whether there is a DRB to which the flow is mapped among at least one established data radio bearer DRB, wherein the mapping of the flow to the DRB is based on information for identifying a flow-based QoS; In the case that the DRB to which the flow is mapped does not exist in at least one established data radio bearer DRB, establishing the DRB; sending a DL packet to the terminal through the DRB, the DL packet including information for identifying a flow-based QoS and an indication associated with reflective QoS, wherein the flow-to-DRB mapping of the DL packet is applied to the flow-to-DRB mapping of the UL packet based on the indication associated with reflective QoS; as well as An uplink UL packet is received from the terminal through the DRB, the UL packet being associated with the flow.

10. The base station according to claim 9, in, The controller is further configured as: In a case where the DRB to which the flow is mapped exists in the at least one established DRB, sending a DL packet to the terminal through the at least one established DRB, The controller is further configured as follows: sending a control message including information about the mapping between flows and DRBs to the terminal, Here, the UL packet is received from the terminal through the DRB identified based on the information about the mapping.

11. The base station according to claim 9, in, The controller is further configured as: receiving, in a case where there is no other DRB to which other flows associated with other UL packets are mapped among the at least one established DRB, other UL packets from the terminal through a default DRB among the at least one established DRB, wherein the other UL packets include information for identifying other QoS based on other flows; and Establish with the terminal the other DRB to which the other flows associated with the other UL packets are mapped.

12. The base station according to claim 9, in, The controller is further configured as: An upper layer of the Packet Data Convergence Protocol (PDCP) layer identifies whether there is a DRB to which the flow is mapped.

13. A terminal in a wireless communication system, the terminal include: Transceiver; as well as A controller is coupled to the transceiver and is configured to: In the case that there is no DRB to which the flow associated with the downlink DL packet is mapped among the at least one established data radio bearer DRB, establishing the DRB to which the flow associated with the DL packet is mapped; receiving a DL packet from a base station through a DRB, the DL packet including information for identifying a flow-based QoS and an indication associated with reflective QoS, wherein the flow-to-DRB mapping of the DL packet is applied to the flow-to-DRB mapping of the UL packet based on the indication associated with reflective QoS; and An uplink UL packet is sent to the base station through the DRB, the UL packet being associated with the flow.

14. The terminal according to claim 13, in, The controller is further configured as: In a case where the DRB to which the flow is mapped exists in the at least one established DRB, receiving a DL packet from the base station through the at least one established DRB, and The controller is further configured as follows: receiving a control message including information about mapping between flows and DRBs from a base station, and The UL packet is transmitted to the base station through the DRB identified based on the information about the mapping.

15. The terminal according to claim 13, in, The controller is further configured as: In the absence of other DRBs to which other flows associated with the other UL packets are mapped, sending other UL packets to the base station through a default DRB in the at least one established DRB, wherein the other UL packets include information for identifying other QoS based on other flows, and The other DRB to which the other flow associated with the other UL packet is mapped is established with the base station.

16. The terminal according to claim 15, in, The controller is configured as: An upper layer of the Packet Data Convergence Protocol PDCP layer identifies whether there are other DRBs to which other flows associated with other UL packets are mapped.

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