Method and apparatus for controlling packet duplication by considering dual connectivity in next generation mobile communication systems

Abstract

The present disclosure relates to a communication method and system for integrating a fifth generation (5G) communication system and a technology for the Internet of Things (IoT) for supporting a higher data rate beyond the fourth generation (4G) system. The present disclosure can be applied to smart services based on 5G communication technology and IoT-related technology, such as smart homes, smart buildings, smart cities, smart cars, connected cars, healthcare, digital education, smart retail, safety and security services. An embodiment relates to packet replication control. In addition, an embodiment relates to cell reselection. A communication method, a terminal and a base station are provided. The method includes: receiving system information related to cell reselection of a neighboring cell from a base station on which the terminal resides; when the terminal supports a supplementary uplink (SUL) and the system information includes a first minimum required reception level information related to the SUL, obtaining a first cell selection reception level value based on the first minimum required reception level information related to the SUL; and performing cell reselection to a new air interface (NR) cell based on the first cell selection reception level value.

Description

Technical Field

[0001] The present disclosure relates to packet duplication control considering dual connectivity architecture in a mobile communication system. More specifically, the present disclosure relates to cell reselection in a mobile communication system. Background Art

[0002] In order to meet the increased demand for wireless data services since the deployment of 4G communication systems, efforts have been made to develop improved 5th generation (5G) or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "super 4th generation (4G) networks" or "post-Long Term Evolution (LTE) systems". 5G communication systems are considered to be implemented in higher frequency (millimeter wave (mmWave)) frequency bands (e.g., 60GHz band) in order to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (Multiple-Input Multiple-Output, MIMO), full-dimensional MIMO (Full Dimensional MIMO, FD-MIMO), array antennas, analog beamforming, and massive antenna technology are discussed in 5G communication systems. In addition, in the 5G communication system, system network improvements are being developed based on advanced small cells, cloud radio access network (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, collaborative communications, coordinated multi-points (CoMP), and receiving-end interference elimination. In the 5G system, hybrid frequency shift keying (FSK) and quadrature amplitude modulation (QAM) modulation, frequency and quadrature amplitude modulation (FQAM) and sliding window superposition coding (SWSC) as advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies have been developed.

[0003] The Internet, which is a human-centered connected network in which humans generate and consume information, is now evolving into the Internet of Things (IoT) in which distributed entities (such as things) exchange and process information without human intervention. The Internet of Everything (IoE), which is a combination of IoT technology and big data processing technology through connection with cloud servers, has emerged. As IoT implementation requires technical elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology" and "security technology", sensor networks, machine-to-machine (M2M) communication, machine type communication (MTC), etc. have been studied recently. This IoT environment can provide intelligent Internet technology services to create new value for human life by collecting and analyzing data generated between networked things. IoT can be applied to multiple fields such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, health care, smart appliances and advanced medical services through the integration and combination of existing information technology (IT) with various industrial applications.

[0004] In line with this, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine type communications (MTC), and machine-to-machine (M2M) communications can be implemented through beamforming, MIMO, and array antennas. Cloud radio access networks (RAN) as an application of the above-mentioned big data processing technology can also be considered as an example of the fusion of 5G technology and IoT technology.

[0005] The above information is presented as background information only to assist with understanding the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with respect to the present disclosure. Summary of the invention

[0006] Technical issues

[0007] Aspects of the present disclosure are to solve at least the above problems and / or disadvantages and provide at least the advantages described below. Therefore, one aspect of the present disclosure is to provide a method for controlling packet replication by considering a dual-connectivity architecture and an apparatus for performing the method.

[0008] Another aspect of the present disclosure is to provide a cell reselection method and an apparatus for performing the method.

[0009] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments.

[0010] Problem Solution

[0011] According to one aspect of the present disclosure, a method of a terminal is provided. The method includes: receiving system information related to cell reselection of a neighboring cell from a base station on which the terminal resides; acquiring a first cell selection reception level value based on the first minimum required reception level information related to the SUL when the terminal supports a supplementary uplink (SUL) and the system information includes first minimum required reception level information related to the SUL; and performing cell reselection to a new radio (NR) cell based on the first cell selection reception level value.

[0012] According to another aspect of the present disclosure, a terminal of a communication system is provided. The terminal includes a transceiver and a controller coupled to the transceiver. The controller is configured to: receive system information related to cell reselection of a neighboring cell from a base station on which the terminal resides; if the terminal supports a supplementary uplink (SUL) and the system information includes first minimum required reception level information related to the SUL, obtain a first cell selection reception level value based on the first minimum required reception level information related to the SUL; and perform cell reselection to a new radio (NR) cell based on the first cell selection reception level value.

[0013] According to another aspect of the present disclosure, a method of a base station is provided. The method includes: identifying a neighboring new radio (NR) cell supporting a supplementary uplink (SUL), generating system information related to cell reselection to the neighboring NR cell supporting SUL, and transmitting the system information, wherein, in a case where a terminal receives the system information and supports SUL, a first cell selection reception level value is acquired based on first minimum required reception level information related to SUL included in the system information, and wherein cell reselection is performed based on the first cell selection reception level value.

[0014] According to another aspect of the present disclosure, a base station is provided. The base station includes a transceiver and a controller coupled to the transceiver. The controller is configured to: identify an adjacent new radio (NR) cell supporting a supplementary uplink (SUL), generate system information related to cell reselection to an adjacent NR cell supporting SUL, and send system information. Wherein, when a terminal receives the system information and supports SUL, a first cell selection reception level value is obtained based on the first minimum required reception level information related to SUL included in the system information, and wherein cell reselection is performed based on the first cell selection reception level value.

[0015] Technical problems to be solved in the embodiments are not limited to the above-mentioned technical problems, and other technical problems not mentioned will be clearly understood by a person having ordinary knowledge in the technical field to which the present disclosure belongs through the following description.

[0016] Technical problems to be solved in the embodiments are not limited to the above-mentioned technical problems, and other technical problems not mentioned will be clearly understood by a person having ordinary knowledge in the technical field to which the present disclosure belongs through the following description.

[0017] Advantageous Effects of the Invention

[0018] The embodiments may provide a method of controlling packet duplication by considering a dual connectivity architecture and an apparatus for performing the method.

[0019] Furthermore, the embodiments may provide a cell reselection method considering uplink and an apparatus for performing the method.

[0020] Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses various embodiments of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description in conjunction with the accompanying drawings, in which:

[0022] Figure 1A is a block diagram showing the structure of a data radio bearer configured with packet copy transmission according to an embodiment of the present disclosure;

[0023] Figure 1B A form in which a base station controls activation or deactivation of packet duplication according to an embodiment of the present disclosure is shown;

[0024] Figure 1C The format of a packet replication activation / deactivation message according to an embodiment of the present disclosure is shown;

[0025] Figure 1D is a signal flow diagram illustrating a method for configuring a data radio bearer configured for packet duplication according to an embodiment of the present disclosure;

[0026] Figure 1E is a flow chart illustrating a method for distinguishing a message for applying an activation state or a deactivation state of a radio bearer and a message for not applying an activation state or a deactivation state of a radio bearer according to an embodiment of the present disclosure;

[0027] Figure 1Fis a flow chart illustrating a method for distinguishing a message for applying an activation state or a deactivation state of a radio bearer and a message for not applying an activation state or a deactivation state of a radio bearer according to an embodiment of the present disclosure;

[0028] Figure 1G is a flow chart illustrating a method for distinguishing a message for applying an activation state or a deactivation state of a radio bearer and a message for not applying an activation state or a deactivation state of a radio bearer according to an embodiment of the present disclosure;

[0029] Figure 1H is a flow chart illustrating a method for distinguishing a message for applying an activation state or a deactivation state of a radio bearer and a message for not applying an activation state or a deactivation state of a radio bearer according to an embodiment of the present disclosure;

[0030] Fig. 1I is a flow chart illustrating a method for distinguishing a message for applying an activation state or a deactivation state of a radio bearer and a message for not applying an activation state or a deactivation state of a radio bearer according to an embodiment of the present disclosure;

[0031] Figure 1J is a flow chart illustrating a method for distinguishing a message for applying an activation state or a deactivation state of a radio bearer and a message for not applying an activation state or a deactivation state of a radio bearer according to an embodiment of the present disclosure;

[0032] Figure 1K is a flow chart illustrating a method for applying an activation or deactivation state of a radio bearer according to an embodiment of the present disclosure;

[0033] Figure 1L is a block diagram showing a configuration of a terminal according to an embodiment of the present disclosure;

[0034] Figure 1M is a block diagram showing a configuration of a base station according to an embodiment of the present disclosure;

[0035] Figure 2A A Long Term Evolution (LTE) base station connected to a next generation mobile communication network according to an embodiment of the present disclosure is shown;

[0036] Figure 2B An additional application of uplink frequency according to an embodiment of the present disclosure is shown;

[0037] Figure 2CA and 2CBis a flowchart illustrating a process for broadcasting frequency specific priority information for cell reselection via a System Information Block (SIB) or applying frequency specific priority information for cell reselection to a specific terminal through an RRC connection release message as dedicated Radio Resource Control (RRC) signaling according to various embodiments of the present disclosure;

[0038] Figure 2D A method for performing cell reselection by a terminal according to an embodiment of the present disclosure is shown;

[0039] Figure 2E is a flowchart showing an operation of a terminal camped on LTE in Embodiment 2-1 according to an embodiment of the present disclosure for performing cell reselection to a new radio (NR) cell;

[0040] Figure 2F is a flowchart showing an operation of a terminal camped on LTE in Embodiment 2-1 according to an embodiment of the present disclosure for performing cell reselection to an NR cell;

[0041] Figure 2G is a flowchart showing an operation of a terminal camped on an NR in Embodiment 2-2 according to an embodiment of the present disclosure for performing cell reselection to a neighboring NR cell;

[0042] Figure 2H is a flowchart showing an operation of a terminal camped on an NR in Embodiment 2-2 according to an embodiment of the present disclosure for performing cell reselection to a neighboring NR cell;

[0043] Fig.2I is a block diagram showing a configuration of a terminal according to an embodiment of the present disclosure; and

[0044] Figure 2J is a block diagram showing a configuration of a base station according to an embodiment of the present disclosure.

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

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

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

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

[0049] When describing the embodiments in this specification, descriptions of technical contents that are well-known in the technical field to which the present disclosure belongs and are not directly related to the present disclosure will be omitted. This omission of unnecessary descriptions is intended to prevent blurring the subject matter of the present disclosure and to convey its subject matter more clearly.

[0050] For the same reason, some elements are exaggerated, omitted or schematically shown in the accompanying drawings. In addition, the size of each element does not fully reflect its actual size. In each of the accompanying drawings, the same or corresponding elements are represented by the same reference numerals.

[0051] By referring to the embodiments described in detail below with reference to the accompanying drawings, the advantages and features of the present disclosure and the methods for achieving them will become apparent. However, the present disclosure is not limited to the embodiments disclosed herein, but can be implemented in various different forms. The following embodiments are provided only for the completeness of the present disclosure, and fully inform those skilled in the art of the scope of the present disclosure, and the present disclosure is limited only by the scope of the attached claims. Throughout the specification, the same or similar reference numerals represent the same or similar elements.

[0052] Here, it is understood that each block of the process flow chart and the combination of the flow chart can be performed by computer program instructions. Since these computer program instructions can be loaded into a processor for a general-purpose computer, a special-purpose 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 (multiple) blocks of the flow chart. Since these computer program instructions can also be stored in a computer-available 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-available or computer-readable memory can also produce a manufactured product including an instruction device for performing the functions described in the (multiple) blocks of the flow chart. Since the computer program instructions can also be loaded into a computer or other programmable data processing device, these instructions can cause a series of operating steps to be performed on the computer or other programmable data processing device to generate a process that can be run by a computer, and enable the computer or other programmable data processing device to operate, and can also provide steps for implementing the functions described in the (multiple) flow chart blocks.

[0053] In addition, each block may indicate some of the modules, segments or codes that include one or more executable instructions for running (multiple) specific logic functions. In addition, it should be noted that in some alternative embodiments, the functions mentioned in the blocks may not occur in order. For example, two blocks shown in succession may be executed substantially simultaneously, or may sometimes be executed in reverse order, depending on the corresponding functions.

[0054] Here, the term "~ unit" used in the embodiment means a software or hardware element, such as a Field-Programmable Gate Array (FPGA) and an Application-Specific Integrated Circuit (ASIC), and the "~ unit" can perform any role. However, the meaning of "~ unit" is not limited to software or hardware. "~ unit" can be configured to reside in an addressable storage medium, and can also be configured to reproduce one or more processors. Accordingly, for example, "~ unit" includes: elements such as software elements, object-oriented software elements, class elements and task elements; and processors, functions, attributes, programs, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays and variables. The functions provided in the elements and "~ units" can be combined with a smaller number of elements and "~ units", or can be further divided into additional elements and "~ units". In addition, elements and "~ units" can also be implemented to reproduce one or more central processing units (CPUs) in a device or a secure multimedia card.

[0055] <First Embodiment>

[0056] Figure 1A is a block diagram showing the structure of a data radio bearer (DRB) configured with packet copy transmission according to an embodiment of the present disclosure.

[0057] refer to Figure 1A , assuming that three DRBs are configured, namely DRB1 1a-10, DRB2 1a-20 and DRB31a-30, and each DRB corresponds to a Packet Data Convergence Protocol (PDCP) device. Packet replication is performed by duplicating a packet at the PDCP layer of the transmitter and passing it to each different Radio Link Control (RLC) device. To this end, the DRB configured with packet replication requires at least two RLC devices to correspond to one PDCP. Figure 1AIn the embodiment, PDCP1 1a-10 is connected to RLC1 1a-40 and RLC2 1a-50, PDCP2 1a-20 is connected to RLC3 1a-60 and RLC4 1a-70, and PDCP3 1a-30 is connected to RLC5 1a-80 and RLC6 1a-90. RLC devices connected to one PDCP device may be classified into: primary RLC devices 1a-40, 1a-60, and 1a-80; and secondary RLC devices 1a-50, 1a-70, and 1a-90. The primary RLC devices 1a-40, 1a-60, and 1a-80 are RLC devices configured to perform packet delivery at the PDCP layer of the transmitter regardless of whether packet copying is activated, and the secondary RLC devices 1a-50, 1a-70, and 1a-90 are configured to perform packet delivery at the PDCP layer of the transmitter only when packet copying is activated. Figure 1A In the embodiment of FIG. 1 , it is assumed that the primary RLC of DRB1 1a-10 is RLC11a-40, the primary RLC of DRB2 1a-20 is RLC2 1a-60, and the primary RLC of DRB3 1a-30 is RLC3 1a-80.

[0058] For such packet duplication transmission, the terminal is connected to two base stations in a dual-connection or multi-connection architecture, and a data radio bearer configured with packet duplication may also be configured. In this example, the connections with each base station may be classified into a cell group (CG). Figure 1A The embodiment of the present invention assumes a dual connectivity architecture and implements configurations of Master Cell Groups (MCG) 1a-100 assuming connection with a primary base station and configurations of Secondary Cell Groups (SCG) 1a-110 assuming connection with a secondary base station. Figure 1AIn the embodiment of , all RLC devices 1a-40 and 1a-50 connected to DRB1 1a-10 are connected to MCG 1a-100, and this configuration means that packet copy transmission performed by DRB1 1a-10 is performed on MCG 1a-100. In this example, a list of cells that each RLC device can use can be pre-specified, and each RLC device performs data transmission only on the cells specified in the list. Since, among the RLC devices connected to DRB2 1a-20, RLC3 1a-60 is connected to MCG 1a-100, and RLC4 1a-70 is connected to SCG 1a-110, this configuration means that packet copy transmission performed by DRB2 1a-20 is performed on both MCG 1a-100 and SCG 1a-110. Since all RLC devices 1a-80 and 1a-90 connected to DRB3 1a-30 are connected to SCG 1a-110, this configuration means that packet copy transmission performed by DRB3 1a-30 is performed on SCG 1a-110. In this example, a list of cells that each RLC device can use can be specified in advance, and each RLC device performs data transmission only on the cells specified in the list.

[0059] DRBs configured with packet replication transmission can be classified into dual connectivity (DC) type packet replication (DC replication) and carrier aggregation (CA) type packet replication (CA replication). The DC type packet replication assumes that packet transmission is performed on bearers in which each RLC device is connected to a different CG, as in the case of DRB21a-20. The CA type packet replication assumes that, as in the case of DRB1 1a-10 and DRB3 1a-30, all RLC devices are connected to the same cell group, and a list of cells that each RLC device can use is pre-specified.

[0060] Figure 1B A form in which a base station controls activation or deactivation of packet duplication according to an embodiment of the present disclosure is shown.

[0061] refer to Figure 1B , packet copy transmission is configured to send the same packet by using at least two RLC devices, thereby increasing the consumption of radio resources. Since packet copy transmission may cause inefficiency in radio resource utilization, it is not good to always perform packet copying. Therefore, packet copy transmission can be performed only when necessary, and the configuration that allows the radio bearer configured with packet copy to actually perform packet copying is called "activation of packet copying". On the contrary, the configuration that allows the radio bearer configured with packet copy not to perform packet copying is called "deactivation of packet copying".

[0062] In operation 1b-10, the base station may send a packet duplication activation / deactivation message to the terminal. In this example, the message used may use the same form of message for activation or deactivation, and the included value may be used to distinguish between activation of packet duplication and deactivation thereof. The packet duplication activation / deactivation message may indicate on which radio bearer the packet duplication is activated or deactivated. In operation 1b-20, after the terminal receives the message, the terminal may apply activation or deactivation of the packet duplication according to the indication included in the message.

[0063] Figure 1C The format of the packet replication activation / deactivation message according to an embodiment of the present disclosure is shown.

[0064] refer to Figure 1C , assuming that the message has a medium access control (MAC) control element (CE) format including one byte (i.e., eight bitmaps). The bits of each of the eight bitmaps indicate activation or deactivation of packet copy transmission on a specific radio bearer, and "1" may indicate activation, and "0" may indicate deactivation. Figure 1C The eight bitmaps in may indicate the activation or deactivation status of packet duplication on each of up to eight radio bearers.

[0065] An embodiment proposes to use a duplicate activation / deactivation message to send the activation or deactivation status of a radio bearer. In this example, which radio bearer will be indicated by each bitmap within the duplicate activation / deactivation message implemented by applying one of the following configurations:

[0066] - a bitmap indication in ascending or descending order of identifiers (IDs) of the DRBs among the DRBs, wherein packet duplication is configured for each DRB and each DRB comprises an RLC device connected to a cell group on which a corresponding MAC CE (MAC CE for indicating duplication activation or deactivation on a radio bearer) is sent;

[0067] - a bitmap indication in ascending or descending order of the IDs of the DRBs among the DRBs, wherein packet duplication is configured for each DRB and each DRB comprises a primary RLC device connected to a cell group on which a corresponding MAC CE is sent;

[0068] - a bitmap indication in ascending or descending order of the IDs of the DRBs among the DRBs, wherein packet duplication is configured for each DRB and each DRB comprises a secondary RLC device connected to a cell group on which a corresponding MAC CE is transmitted;

[0069] - a bitmap indication in ascending or descending order of IDs of DRBs among DRBs, wherein packet duplication is configured for each DRB and each DRB includes a PDCP anchor of a base station included in a base station node corresponding to a cell group on which a corresponding MAC CE is transmitted;

[0070] - a bitmap indication in ascending or descending order of the IDs of the DRBs among the DRBs, wherein packet duplication is configured for each DRB and each DRB includes an encryption key (security key) of a base station node corresponding to a cell group on which a corresponding MAC CE is sent;

[0071] - an indication of activation or deactivation of packet duplication by using a corresponding MAC CE, a bitmap indication in ascending or descending order of DRB IDs among DRBs, wherein packet duplication pre-configured by the base station is configured for each DRB;

[0072] - In case the MAC CE is sent over the MCG, a bitmap indication is given in ascending or descending order regarding the IDs of the DRBs for which the CA type packet replication configured by the MCG is configured and the DRBs for which the DC type packet replication configured by the MCG is configured. In case the MAC CE is sent over the SCG, a bitmap indication is given in ascending or descending order regarding the IDs of the DRBs for each of which the CA type packet replication configured by the SCG is configured; or

[0073] -The base station specifies the bitmap location of a specific MAC CE.

[0074] Figure 1D is a signal flow diagram illustrating a process for configuring a DRB configured for packet replication according to an embodiment of the present disclosure.

[0075] refer to Figure 1D In operation 1d-10, the base station sends a radio resource control (RRC) configuration message to the terminal. The base station can generate or modify a radio bearer by using the RRC configuration message, and can configure packet duplication for the radio bearer. In this example, the base station can configure a DRB ID for each radio bearer and a logical channel ID corresponding to each RLC device, and can configure the DRB ID for each radio bearer by corresponding to these IDs. Figure 1A The PDCP device configuration shown in FIG. 1 includes radio bearers of at least two RLC devices. In this example, the base station can be configured so that the primary RLC device is distinguished from the secondary RLC device among the RLC devices. In operation 1d-20, the terminal can receive the configuration message, and after the configuration change of the terminal is completed, an RRC configuration complete message can be sent to the base station. The terminal can use the RRC configuration complete message to notify the base station that the configuration according to the configuration message has been completed.

[0076] Figure 1E Detailed description is a flowchart illustrating a method for distinguishing a duplicate activation / deactivation message for an activation state or a deactivation state of an applied radio bearer and a duplicate activation / deactivation message for an activation state or a deactivation state of a non-applied radio bearer according to an embodiment of the present disclosure.

[0077] refer to Figure 1E , it can be assumed that the format of the packet replication activation / deactivation message adopts the reference Figure 1C The MACCE format described in the description is not limited to this. If packet replication is configured for the DRB in operation 1e-10, then in operation 1e-20, the terminal may determine, for all CGs used by the terminal, whether the MAC CE received on a specific cell group will be used to activate or deactivate the packet replication of the DRB for the cell group. In operation 1e-20, the cell group to which the network node at which the base station PDCP anchor of the DRB (for which the activation or deactivation of packet replication is to be determined) is located can be a determination criterion. If the base station PDCP anchor of the DRB is located at a network node connected to the first cell group, then in operation 1e-30, the terminal may apply the activation or deactivation of the packet replication of the DRB by using the MAC CE sent on the first cell group. If the base station PDCP anchor of the DRB is not located at a network node connected to the first cell group, then in operation 1e-40, the terminal does not apply the activation or deactivation of the packet replication of the relevant DRB by using the MAC CE sent on the first cell group. For example, for DRB, if the base station PDCP anchor is located at the master node, the terminal applies activation or deactivation of packet replication of DRB by using the MAC CE received on the MCG, instead of applying activation or deactivation of packet replication of DRB by using the MAC CE received on the SCG. However, although the MAC CE is not used to apply activation or deactivation of packet replication to DRB, the bitmap may correspond to the DRB in the MAC CE. Even if any bitmap of the MAC CE corresponds to the DRB, the terminal may ignore the bitmap when the relevant MAC CE is not used to apply activation or deactivation of packet replication.

[0078] Figure 1F Detailed description is a flowchart illustrating a method for distinguishing a duplicate activation / deactivation message for an activation state or a deactivation state of an applied radio bearer and a duplicate activation / deactivation message for an activation state or a deactivation state of a non-applied radio bearer according to an embodiment of the present disclosure.

[0079] refer to Figure 1F In this case, it can be assumed that the format of the packet replication activation / deactivation message adopts the reference Figure 1CThe MACCE format described above is not limited to this. If packet replication is configured for the DRB in operation 1f-10, then in operation 1f-20, the terminal may determine, for all CGs used by the terminal, whether the MAC CE received on a specific cell group will be used to activate or deactivate the packet replication of the DRB for the cell group. In operation 1f-20, which cell group the network node is connected to (wherein the security key used by the DRB is a security key corresponding to the network node) may be a determination criterion. If the security key used by the DRB is a security key corresponding to the network node connected to the first cell group, then in operation 1f-30, the terminal may apply activation or deactivation of packet replication of the DRB by using the MAC CE sent on the first cell group. If the security key used by the DRB is not a security key corresponding to the network node connected to the first cell group, then in operation 1f-40, the terminal does not apply activation or deactivation of packet replication of the DRB by using the MAC CE sent on the first cell group. For example, if the security key used by the DRB is the KgNB as the security key of the primary node, the terminal applies activation or deactivation of packet replication of the DRB by using the MAC CE received on the MCG. If the security key used by the DRB is the S-KgNB as the security key of the secondary node, the terminal applies activation or deactivation of packet replication of the DRB by using the MAC CE received on the SCG. However, although the MAC CE is not used to apply activation or deactivation of packet replication to the DRB, the bitmap may correspond to the DRB in the MAC CE. Even if any bitmap of the MAC CE corresponds to the DRB, the terminal may ignore the bitmap when the relevant MAC CE is not used to apply activation or deactivation of packet replication.

[0080] Figure 1G Detailed description is a flowchart illustrating a method for distinguishing a duplicate activation / deactivation message for an activation state or a deactivation state of an applied radio bearer and a duplicate activation / deactivation message for an activation state or a deactivation state of a non-applied radio bearer according to an embodiment of the present disclosure.

[0081] refer to Figure 1G , it can be assumed that the format of the packet replication activation / deactivation message adopts the reference Figure 1CThe MACCE format described above is not limited to this. If packet replication is configured for the DRB in operation 1g-10, in operation 1g-20, the terminal may determine, for all CGs used by the terminal, whether the MAC CE received on a specific cell group will be used to activate or deactivate packet replication of the DRB of the cell group. In operation 1g-20, whether the relevant cell group is the cell group used by the primary RLC of the relevant DRB may become a determination criterion. If the primary RLC of the DRB is connected to the first cell group, in operation 1g-30, the terminal may apply activation or deactivation of packet replication of the DRB by using the MAC CE sent on the first cell group. If the primary RLC of the DRB is not connected to the first cell group, in operation 1g-40, the terminal may not apply activation or deactivation of packet replication of the relevant DRB by using the MAC CE sent on the first cell group. For example, if the primary RLC of the DRB is connected to the MCG, the terminal applies activation or deactivation of packet replication of the DRB by using the MAC CE received on the MCG, but does not apply activation or deactivation of packet replication of the DRB by using the MAC CE received on the SCG. However, although the MAC CE is not used to apply activation or deactivation of packet replication to the DRB, the bitmap may correspond to the DRB in the MAC CE. Even if any bitmap of the MAC CE corresponds to the DRB, the terminal may ignore the bitmap when the relevant MAC CE is not used to apply activation or deactivation of packet replication.

[0082] Figure 1H Detailed description is a flowchart illustrating a method for distinguishing a duplicate activation / deactivation message for an activation state or a deactivation state of an applied radio bearer and a duplicate activation / deactivation message for an activation state or a deactivation state of a non-applied radio bearer according to an embodiment of the present disclosure.

[0083] refer to Figure 1H , it can be assumed that the format of the packet replication activation / deactivation message adopts the reference Figure 1CThe MACCE format described above is not limited to this. If packet replication is configured for the DRB in operation 1h-10, in operation 1h-20, the terminal may determine whether the MAC CE received on a specific cell group will be used to activate or deactivate packet replication of the DRB for all CGs used by the terminal. In operation 1h-20, whether the relevant cell group is the cell group used by the secondary RLC of the relevant DRB may become a determination criterion. If the secondary RLC of the DRB is connected to the first cell group, in operation 1h-30, the terminal may apply activation or deactivation of packet replication of the DRB by using the MAC CE sent on the first cell group. If the secondary RLC of the DRB is not connected to the first cell group, in operation 1h-40, the terminal does not apply activation or deactivation of packet replication of the DRB by using the MAC CE sent on the first cell group. For example, if the secondary RLC of the DRB is connected to the MCG, the terminal applies activation or deactivation of packet replication of the DRB by using the MAC CE received on the MCG, instead of applying activation or deactivation of packet replication of the DRB by using the MAC CE received on the SCG. However, although the MAC CE is not used to apply activation or deactivation of packet replication to the DRB, the bitmap may correspond to the DRB in the MAC CE. Even if any bitmap of the MAC CE corresponds to the DRB, the terminal may ignore the bitmap when the relevant MAC CE is not used to apply activation or deactivation of packet replication.

[0084] Fig. 1I Detailed description is a flowchart illustrating a method for distinguishing a duplicate activation / deactivation message for an activation state or a deactivation state of an applied radio bearer and a duplicate activation / deactivation message for an activation state or a deactivation state of a non-applied radio bearer according to an embodiment of the present disclosure.

[0085] refer to Fig. 1I , it can be assumed that the format of the packet replication activation / deactivation message adopts the reference Figure 1C The MACCE format described in the above description is not limited to this. If packet replication is configured for the DRB in operation 1i-10, then in operation 1i-20, the terminal may determine, for all CGs used by the terminal, whether a MAC CE received on a specific cell group will be used to activate or deactivate packet replication of the DRB. In operation 1i-20, whether the base station configures a cell group on which a MAC CE for activating or deactivating application of packet replication to the relevant DRB is sent may become a determination criterion. In this example, the configuration of the base station may be Figure 1DIndicated in the RRC configuration message. If the base station configures a cell group on which a MAC CE for controlling activation or deactivation of packet replication on the relevant DRB will be sent, then in operation 1i-30, the terminal can apply activation or deactivation of packet replication for the DRB by using the MAC CE sent on the cell group. If the base station does not configure a cell group on which a MAC CE for controlling activation or deactivation of packet replication on the DRB will be sent, then in operation 1i-40, the terminal does not apply activation or deactivation of packet replication for the DRB by using the MAC CE sent on the cell group. For example, if activation or deactivation of packet replication for the DRB is configured to be applied using a MAC CE received on the MCG, the terminal applies activation or deactivation of packet replication for the DRB by using the MAC CE received on the MCG, but does not apply activation or deactivation of packet replication for the DRB by using the MAC CE received on the SCG. However, although the MAC CE is not used to apply activation or deactivation of packet replication to the DRB, the bitmap may correspond to the DRB in the MAC CE. Even if any bitmap of MAC CE corresponds to DRB, the terminal may ignore the bitmap when the relevant MAC CE is not used for activation or deactivation of application packet duplication.

[0086] Figure 1J Detailed description is a flowchart illustrating a method for distinguishing a duplicate activation / deactivation message for an activation state or a deactivation state of an applied radio bearer and a duplicate activation / deactivation message for an activation state or a deactivation state of a non-applied radio bearer according to an embodiment of the present disclosure.

[0087] refer to Figure 1J , it can be assumed that the format of the packet replication activation / deactivation message adopts the reference Figure 1C The MACCE format described in the above description is not limited to this. If packet replication is configured for the DRB in operation 1j-10, then in operation 1j-20, the terminal may determine, for all CGs used by the terminal, whether the MAC CE received on a specific cell group will be used to activate or deactivate packet replication for the DRB. In this example, only a specific cell group can control the activation or deactivation of packet replication on the relevant DRB. Figure 1JIn an embodiment of the present invention, in operation 1j-30, the terminal applies activation or deactivation of packet replication to each DRB among all DRBs for which packet replication is configured, using only the MAC CE received on the MCG. In operation 1j-40, the terminal does not apply activation or deactivation of packet replication by using a MAC CE received on another cell group that is not the MCG. However, although the MAC CE is not used to apply activation or deactivation of packet replication to the DRB, the bitmap may correspond to the DRB in the MAC CE. Even if any bitmap of the MAC CE corresponds to a DRB, the terminal may ignore the bitmap when the relevant MAC CE is not used to apply activation or deactivation of packet replication. Figure 1J In the embodiment, it is assumed that only the MAC CE received on the MCG is used to control the activation or deactivation of packet duplication, but the criterion can be specified to the SCG or a specific cell group and thus can be applied to this criterion.

[0088] Figure 1K is a flow chart illustrating a method for applying an activation or deactivation state of a radio bearer according to an embodiment of the present disclosure.

[0089] refer to Figure 1K , it can be assumed that the format of the packet replication activation / deactivation message adopts the reference Figure 1C The MACCE format described in the description is not limited to this. If the base station configures packet replication for the DRB in operation 1k-10, then in operation 1k-20, the terminal can identify whether the relevant radio bearer is a dual-connection radio bearer. In operation 1k-30, if the relevant DRB is a dual-connection radio bearer, the always active state can be applied to the packet replication of the DRB. In this example, the base station can configure the MAC CE so that the packet replication of the dual-connection radio bearer for which packet replication is configured is always activated according to a pre-configured scheme. Alternatively, the terminal can always apply the activation of packet replication regardless of which value the MAC CE is set to. If the DRB is not a dual-connection radio bearer, then in operation 1k-40, a node determines the activation or deactivation of packet replication for the DRB, and therefore does not use the MAC CE to apply the activation or deactivation of packet replication for the DRB. However, although the MAC CE is not used to apply activation or deactivation of packet replication to the DRB, the bitmap may correspond to the DRB in the MAC CE. Even if any bitmap of MAC CE corresponds to DRB, the terminal may ignore the bitmap when the relevant MAC CE is not used for activation or deactivation of application packet duplication.

[0090] Figure 1L is a block diagram showing a configuration of a terminal according to an embodiment of the present disclosure.

[0091] refer to Figure 1L , the terminal may include a transceiver 11-10, a controller 11-20, and a storage unit 11-30. In the present disclosure, the controller 11-20 may be defined as a circuit, an ASIC, or at least one processor.

[0092] The transceiver 11-10 may send a signal to another network entity or receive a signal from another network entity. For example, the transceiver 11-10 may receive system information from a base station and may receive a synchronization signal or a reference signal therefrom.

[0093] According to the embodiments proposed in the present disclosure, the controller 11-20 can control the overall operation of the terminal. For example, the controller 11-20 can control the signal flow between the blocks so as to perform the above operations according to the above flowchart.

[0094] The storage unit 11-30 may store at least one piece of information among information transmitted or received by the transceiver 11-10 and information generated by the controller 11-20 of the terminal.

[0095] Figure 1M is a block diagram showing a configuration of a base station according to an embodiment of the present disclosure.

[0096] refer to Figure 1M , the base station may include a transceiver 1m-10, a controller 1m-20, and a storage unit 1m-30. In the present disclosure, the controller 1m-20 may be defined as a circuit, an ASIC, or at least one processor.

[0097] The transceiver 1m-10 may send a signal to another network entity or receive a signal from another network entity. For example, the transceiver 1m-10 may send system information to the terminal and may send a synchronization signal or a reference signal thereto.

[0098] According to the embodiments proposed in the present disclosure, the controller 1m-20 can control the overall operation of the base station. For example, the controller 1m-20 can control the signal flow between blocks so as to perform the above operations according to the above flowchart.

[0099] The storage unit 1m-30 may store at least one piece of information among information transmitted or received by the transceiver 1m-10 and information generated by the controller 1m-20.

[0100] <Second Embodiment>

[0101] Figure 2A The structure of a next generation mobile communication system according to an embodiment of the present disclosure is shown.

[0102] refer to Figure 2AThe radio access network of the next generation mobile communication system (NR) includes a next generation base station (NR NodeB) (hereinafter referred to as "gNB") 2a-10 and an access and mobility management function (Access and Mobility Management Function, AMF) (NR core network) 2a-05. User equipment (NR user equipment) (hereinafter referred to as "NRUE", "UE" or "terminal") 2a-15 accesses the external network through gNB 2a-10 and AMF 2a-05.

[0103] exist Figure 2A In the figure, gNB 2a-10 corresponds to the evolved Node B (eNB) of the existing long term evolution (LTE) system. The gNB 2a-10 is connected to the NR UE 2a-15 through a wireless channel and can provide services that are superior to those provided by the existing Node B (as shown in the figure 2a-20). In the next generation mobile communication system, since all user services are provided through a shared channel, a device configured to collect the status information of the UE (including buffer status, available transmission power status, channel status, etc.) and thus perform scheduling is required, and the gNB 2a-10 is used as the device. One gNB generally controls multiple cells. In order to implement ultra-high-speed data transmission compared to the current LTE, the existing maximum bandwidth or larger bandwidth can be provided, and orthogonal frequency division multiplexing (hereinafter referred to as "OFDM") can be used as a wireless access technology, and beamforming technology can be additionally combined with it. In addition, an adaptive modulation and coding (hereinafter referred to as "AMC") scheme that determines the modulation scheme and channel coding rate according to the channel state of the terminal is applied. AMF 2a-05 performs functions including mobility support, bearer configuration, Quality of Service (QoS) configuration, etc. AMF 2a-05 is a device for performing various control functions of the terminal in addition to the mobility management function of the terminal, and is connected to multiple base stations. In addition, the next-generation mobile communication system can interoperate with the existing LTE system, and AMF 2a-05 is connected to the Mobility Management Entity (MME) 2a-25 of the LTE system through a network interface. MME 2a-25 is connected to eNB 2a-30, which is an existing base station. A terminal 2a-15 supporting LTE-NR dual connectivity can send or receive data while maintaining not only a connection with the gNB 2a-10 but also a connection with the eNB 2a-30 (as shown in the figure mark 2a-35).

[0104] Figure 2B Additional applications of uplink frequencies according to embodiments of the present disclosure are shown.

[0105] refer to Figure 2B In a mobile communication system, a phenomenon in which the uplink coverage is inconsistent with the downlink coverage may occur. The inconsistency phenomenon occurs due to the difference between the uplink channel characteristics and the downlink channel characteristics, the limitation of the maximum transmit power of the terminal, or the structural limitation of the transmitting antenna. Generally, the downlink coverage is greater than the uplink coverage. As an example, in a time division duplex (TDD) system of the 3.5GHz frequency band, the downlink coverage 2b-05 is greater than the uplink coverage 2b-10. In this example, the first terminal 2b-20 has no problem receiving services in the uplink and downlink, but the second terminal 2b-25 encounters problems when successfully sending data to the base station 2b-15 in the uplink. Therefore, in order to eliminate the problems caused by the above inconsistency, the effective downlink coverage can be reduced to be consistent with the uplink coverage. That is, although a larger coverage can be provided in the downlink, the downlink coverage is limited to the uplink coverage.

[0106] In order to solve the performance limitation caused by this inconsistency, the next generation mobile communication system allows the terminal to apply an uplink frequency with greater coverage. As an example, an uplink coverage 2b-30 of 1.8GHz separated from the uplink coverage of 3.5GHz is additionally provided to the terminal. The additional uplink frequency is called "supplementary uplink (SUL) frequency". Therefore, due to the frequency characteristics, the lower the frequency band, the longer the propagation distance of the wireless signal. Therefore, 1.8GHz below 3.5GHz allows greater coverage. As a result, the second terminal 2b-50 can successfully send data to the base station 2b-40 by using the uplink coverage 2b-30 of 1.8GHz. In addition, the first terminal 2b-45 is not affected by the coverage problem, but can use both the uplink coverage of 1.8GHz and the uplink coverage of 3.5GHz. Therefore, the first terminal 2b-45 can select one of 1.8GHz and 3.5GHz to disperse the uplink access congestion, and can use them. The additional uplink frequency can be an LTE frequency.

[0107] Both the NR uplink frequency and the SUL frequency can be configured for one terminal, and in this example, the Physical Uplink Shared Channel (PUSCH) as an uplink data channel can be sent only in one uplink at a time. The Physical Uplink Control Channel (PUCCH) can also be sent only in one uplink at a time, and can be sent in the same or different uplink as the uplink in which the PUSCH is sent.

[0108] Figure 2CA and 2CB This is a portion of a flowchart illustrating a process for broadcasting frequency specific priority information for cell reselection via SIB in LTE technology or applying frequency specific priority information for cell reselection to a specific terminal through an RRC connection release message as dedicated RRC signaling according to various embodiments of the present disclosure.

[0109] refer to Figure 2CA and 2CB , cell reselection refers to the process for reselecting a serving cell so that a mobile terminal can connect to a cell with the best channel state. The network assigns a priority to each frequency, thereby controlling the cell reselection of a terminal in idle mode. For example, a terminal has received priority information for two frequencies f1 and f2, and if f1 has a higher priority than f2, the probability that the terminal will stay on f1 becomes higher. In addition, although the terminal stays on f2, if the channel state of f2 is not good, the terminal may try to switch to f1. The priority information of the frequency may be broadcast via the SIB, or may be provided to a specific terminal via an RRC connection release message as a dedicated RRC signaling. Although the terminal already has priority information for the frequency via the SIB, if the terminal receives UE-specific priority information via RRC signaling, the priority information of the SIB is ignored. The priority information of each frequency is transmitted through the cellReselectionPriority (cell reselection priority) information element (IE) described below, and each frequency is assigned one of the priorities with a total of (X+1) levels. A smaller value indicates a lower priority. That is, "0" indicates the lowest priority.

[0110] cellReselectionPriority Information Element

[0111]

[0112] Frequencies associated with Radio Access Technology (RAT) may not be assigned the same priority. If the idle state of the terminal is "camped on any cell state", the frequency priority information received via the SIB is applied, and only the priority information received through RRC signaling is stored without using them. The cellReselectionPriority IE is an optional IE and may not exist. In this example, no priority information for the corresponding frequency is assigned. In this example, the terminal regards the priority of the corresponding frequency as the lowest level.

[0113] In operation 2c-00, the terminal receives priority information of frequencies via SIB, which is used not only by Evolved Universal Terrestrial Radio Access (EUTRA) but also by RATs other than EUTRA. However, priority information of all frequencies is not necessarily provided. Priority information of the frequency of the serving cell on which the terminal is currently residing may also not be provided. In operation 2c-05, the terminal identifies whether priority information of the frequency of the current serving cell exists. If priority information of the frequency of the current serving cell is not provided, in operation 2c-10, the terminal may regard the priority of the frequency as the lowest level.

[0114] In operation 2c-15, the terminal applies the priority information of each frequency received via the SIB. If the terminal receives a radio resource control (RRC) connection release message from the base station, the terminal switches from the connected mode to the idle mode. The RRC connection release message may include priority information of the frequency. The priority information is user equipment (UE)-specific information and is generally applied in preference to the frequency priority information received from the SIB. Therefore, in operation 2c-20, the terminal identifies whether the RRC connection release message includes frequency priority information. If the RRC connection release message includes frequency priority information, in operation 2c-25, the terminal applies the value of the first timer included with the frequency priority information and thus starts the first timer. In operation 2c-30, the terminal determines whether the current idle mode state is "camped in any cell state" or "camped normally state". "Normal camped state" refers to a state in which the terminal camps on a suitable cell. The suitable cell can provide normal services to the terminal and meets the following specific conditions:

[0115] - the cell corresponds to a Public Land Mobile Network (PLMN) in the Selected PLMN List, the Registered PLMN List or the Equivalent PLMN List;

[0116] - No banned communities;

[0117] - Cells that meet the cell selection criteria;

[0118] - "Camped on any cell state" refers to a state in which the terminal fails to camp on a suitable cell and thus camps on an acceptable cell. In an acceptable cell, the terminal cannot receive normal services,

[0119] And you can try emergency calls. Acceptable cells meet the following conditions;

[0120] - There are no prohibited communities; or

[0121] -Cells that meet the cell selection criteria.

[0122] If the terminal is in an idle state corresponding to the "camped on any cell state", instead of applying the priority information received through the RRC connection release message, the terminal returns to operation 2c-15 and applies the frequency priority information received via the SIB. If the terminal is in an idle state corresponding to the "normal camped state", in operation 2c-35, the terminal determines whether at least one of the following three conditions is met. The three conditions are as follows:

[0123] -The terminal switches to connecting mode.

[0124] - The first timer has expired.

[0125] -Perform the PLMN selection process according to the Non-Access Stratum (NAS) request.

[0126] If any one of the above conditions is met, then in operation 2c-40, the terminal deletes the priority information received through the RRC connection release message, and returns to operation 2c-15, and applies the frequency priority information received via the SIB. On the contrary, if any one of the conditions is not met, then in operation 2c-45, the terminal applies the priority information received through the RRC connection release message.

[0127] Frequency priority information affects the terminal's measurement of a specific frequency. The terminal always performs measurements on frequencies with a priority higher than the current serving cell. On the contrary, in order to save terminal power, the terminal does not perform measurements on the same frequency as the serving cell (intra-frequency) or other frequencies each having a priority lower than or equal to the serving cell. If the QoS of the serving cell is less than or equal to a specific threshold, the measurement is performed. In order to move to a cell with a good channel state, cell reselection is performed, and since the current serving cell has a good channel QoS, the terminal has no reason to move to a frequency with a priority lower than or equal to the serving cell. Therefore, in order to reduce power consumption due to unnecessary channel measurements, it is determined whether to perform measurements based on a specific threshold. In the case of the same frequency (intra-frequency), if the QoS of the serving cell is lower than or equal to a specific threshold SintraSearch, the terminal performs channel measurements on other cells with the same frequency. In the case of other frequencies each having a priority lower than or equal to the serving cell, if the QoS of the serving cell is lower than or equal to a specific threshold SintraSearch, the terminal performs channel measurements on the corresponding cells with other frequencies. Generally, channel QoS takes into account Reference Signal Received Power (RSRP) and Reference Signal Received Quality (RSRQ).

[0128] If the channel QoS of the cell with a higher priority frequency becomes higher than a specific threshold ThreshX-high while the terminal performs the above measurement, the terminal reselects the cell with a higher priority frequency as the serving cell. If the channel QoS of the cell with a lower priority frequency is higher than a specific threshold ThreshX-high, and the QoS of the serving cell becomes lower than the threshold ThreshServing-low, the terminal reselects the cell with a lower priority frequency as the serving cell.

[0129] Figure 2D A method for performing cell reselection by a terminal according to an embodiment of the present disclosure is shown.

[0130] refer to Figure 2D, the terminal always performs inter-frequency / inter-RAT measurements on higher priority frequencies or RATs, regardless of the measured signal strength of the serving cell 2d-05. If the measured signal strength of the serving cell 2d-05 is lower than SintraSearch 2d-25, the terminal performs intra-frequency measurements. If the measured signal strength of the serving cell 2d-05 is lower than SnonintraSearch 2d-30, the terminal performs inter-frequency / inter-RAT measurements on frequencies with a priority lower than or equal to the frequency of the current serving cell 2d-05. The reason for gradually triggering terminal measurements is to reduce terminal power consumption due to measurements of neighboring cells. If the channel QoS of the cell 2d-10 with a higher priority frequency becomes higher than a specific threshold ThreshX-high 2d-35, the terminal reselects the cell 2d-10 with a higher priority frequency as the new serving cell. If the channel QoS of the cell 2d-00 with a lower priority frequency is higher than a specific threshold ThreshX-low 2d-15 and the QoS of the serving cell 2d-05 becomes lower than ThreshServing-low 2d-20, the terminal reselects the cell 2d-00 with a lower priority frequency as a new serving cell.

[0131] RSRP or RSRQ may be considered during cell reselection. RSRP or RSRQ represents a value calculated according to the S-criteria. That is, RSRP or RSRQ is Srxlev or Squal.

[0132] Srxlev=Q rxlevmeas -(Q rxlevmin +Q rxlevminoffset )-P compensation -Qoffset temp

[0133] Squal=Q qualmeas -(Q qualmin +Q qualminoffset )-Qoffset temp

[0134] in:

[0135]

[0136]

[0137] Specifically, in case of inter-RAT cell reselection to NR, Srxlev is used, and the value of Srxlev is compared with a specific threshold ThreshX-high or ThreshX-low.

[0138] In an embodiment, if a long term evolution (LTE) base station provides a value of q-RxLevMinSUL related to a specific NR frequency through system information, and the terminal supports SUL, when the terminal performs inter-RAT cell reselection to an NR cell belonging to the NR frequency, the terminal applies the value of q-RxLevMinSUL as the Q value of Srxlev. rxlevmin The value of q-RxLevMinSUL is obtained from the calculation, and the value of Srxlev is derived accordingly. The value of q-RxLevMinSUL is provided for each NR frequency, and if the NR cell belonging to a specific NR frequency supports SUL, the value of q-RxLevMinSUL for the specific NR frequency is provided. For NR frequencies that do not support SUL, the value of q-RxLevMinSUL is not provided. If RSRQ is used, the base station broadcasts Threshserving-lowQ, ThreshX-lowQ and ThreshX-highQ respectively, and provides them to the terminal. If RSRP is used, Threshserving-lowP, ThreshX-lowP and ThreshX-highP are used.

[0139] Figure 2E 2 is a flowchart showing the operation of a terminal residing on LTE performing cell reselection to an NR cell in Embodiment 2-1 according to an embodiment of the present disclosure.

[0140] Referring to 2E, in operation 2e-15, the LTE base station 2e-10 determines whether a neighboring NR base station that supports SUL exists. If a neighboring NR base station that supports SUL exists, inter-RAT cell reselection to the neighboring NR base station may be required. To this end, the LTE base station 2e-10 includes the cell reselection parameter information required when performing inter-RAT cell reselection to a neighboring NR base station that supports SUL in SIB2N, which is one of the system information. If the neighboring NR base station supports SUL, in operation 2e-20, the required cell reselection parameters include at least q-RxLevMinSUL. If the neighboring NR base station does not support SUL, the value of q-RxLevMinSUL is not included in SIB2N. However, for each NR frequency, the value of q-RxLevMin may be included in SIB2N, regardless of whether the NR cell belonging to a specific NR frequency supports the SUL function. A value of q-RxLevMinSUL is provided for each NR frequency. SIB2N is system information that only terminals supporting NR can understand, and mainly includes information about inter-RAT cell reselection to NR. Therefore, terminals that do not support NR do not need to receive SIB2N.

[0141] In operation 2e-25, if the terminal 2e-05 currently camping on an LTE cell supports connection with the NR system, the terminal receives the SIB2N being broadcast by the LTE base station. In operation 2e-30, if the terminal 2e-05 supports the SUL function, in order to derive the value of Srxlev in cell reselection, the terminal 2e-05 applies q-RxLevMinSUL included in SIB2N as Q rxlevmin If the terminal 2e-05 does not support the SUL function, in order to derive the value of Srxlev in cell reselection, the terminal 2e-05 applies q-RxLevMin included in SIB2N as Q rxlevmin The value of .

[0142] Figure 2F 2 is a flowchart showing the operation of a terminal residing on LTE performing cell reselection to an NR cell in Embodiment 2-1 according to an embodiment of the present disclosure.

[0143] refer to Figure 2F In operation 2f-05, if the terminal residing on the LTE base station supports NR, the terminal receives SIB2N from the LTE base station and stores the information included in SIB2N. SIB2N is mainly used to provide parameters required for inter-RAT cell reselection to NR.

[0144] In operation 2f-07, the terminal triggers an inter-RAT cell reselection operation for an NR cell belonging to a specific NR frequency.

[0145] In operation 2f-10, the terminal determines whether the terminal itself supports the SUL function. If the terminal itself supports the SUL function, the terminal proceeds to operation 2f-15. If the terminal itself does not support the SUL function, the terminal proceeds to operation 2f-25.

[0146] In operation 2f-15, the terminal determines whether the received SIB2N includes a value of q-RxLevMinSUL corresponding to a specific NR frequency. The value of q-RxLevMinSUL may be provided for each NR frequency, and if all NR cells belonging to a specific NR frequency support the SUL function, the value of q-RxLevMinSUL for the specific NR frequency should be provided. If SIB2N includes a value of q-RxLevMinSUL corresponding to a specific NR frequency, the terminal proceeds to operation 2f-20. If SIB2N does not include a value of q-RxLevMinSUL corresponding to a specific NR frequency, the terminal proceeds to operation 2f-25.

[0147] If the terminal supports SUL functionality and a value of q-RxLevMinSUL corresponding to a specific NR frequency is provided, then in operation 2f-20, during inter-RAT cell reselection to the specific NR frequency supporting SUL, the terminal applies the received value of q-RxLevMinSUL as Q of Srxlev rxlevmin The value of .

[0148] If the terminal does not support the SUL function or does not provide a value of q-RxLevMinSUL corresponding to a specific NR frequency, then in operation 2f-25, the terminal applies the received value of q-RxLevMin as the Q value of Srxlev. rxlevmin .

[0149] Figure 2G It is a flowchart showing the operation of a terminal residing on NR performing cell reselection to a neighboring NR cell in Embodiment 2-2 according to an embodiment of the present disclosure.

[0150] refer to Figure 2G In operation 2g-15, the NR base station 2g-10, which is a neighboring NR base station supporting SUL, includes in SIBx, which is one of the system information, the cell reselection parameter information required when performing cell reselection (intra-frequency / inter-frequency cell reselection) to an NR cell belonging to the same or different frequency. As an example, parameters related to intra-frequency cell reselection are included in SIB2, and parameters related to inter-frequency cell reselection are included in SIB4. SIBx may belong to other system information (Other System Information, OSI). That is, the system information is broadcast periodically according to the determination made by the base station, or is broadcast only during a predetermined time period in response to the request 2g-20 of the terminal. In operation 2g-25, if the neighboring NR base station supports SUL, SIBx may include at least q-RxLevMinSUL as a necessary cell reselection parameter. If the neighboring NR base station does not support SUL, SIBx does not include the value of q-RxLevMinSUL. However, for each NR frequency, the value of q-RxLevMin is included in SIBx, regardless of whether the NR cell belonging to the specific NR frequency supports the SUL function. The value of q-RxLevMinSUL is provided for each NR frequency. In operation 2g-30, if the terminal 2g-05 currently camping on an NR cell supports the SUL function, in order to derive the value of Srxlev in cell reselection, the terminal applies q-RxLevMinSUL included in SIBx as Q rxlevmin If the terminal 2g-05 does not support the SUL function, in order to derive the value of Srxlev in cell reselection, the terminal applies q-RxLevMin included in SIBx as Q rxlevminThe value of .

[0151] Figure 2H It is a flowchart showing the operation of a terminal residing on NR performing cell reselection to a neighboring NR cell in Embodiment 2-2 according to an embodiment of the present disclosure.

[0152] refer to Figure 2H In operation 2h-05, if the terminal does not store valid SIBx, the terminal requests system information from the currently serving NR base station.

[0153] At operation 2h-10, the terminal stores the SIBx received from the serving base station.

[0154] In operation 2h-13, the terminal triggers an intra-frequency / inter-frequency cell reselection operation for an NR cell belonging to a specific NR frequency.

[0155] In operation 2h-15, the terminal determines whether the terminal itself supports the SUL function. If the terminal itself supports the SUL function, the terminal proceeds to operation 2h-20. If the terminal itself does not support the SUL function, the terminal proceeds to operation 2h-30.

[0156] In operation 2h-20, the terminal determines whether the received SIBx includes a value of q-RxLevMinSUL corresponding to a specific NR frequency. The value of q-RxLevMinSUL may be provided for each NR frequency, and if all NR cells belonging to a specific NR frequency support the SUL function, the value of q-RxLevMinSUL for the specific NR frequency should be provided. If the received SIBx includes a value of q-RxLevMinSUL corresponding to a specific NR frequency, the terminal proceeds to operation 2h-25. If the received SIBx does not include a value of q-RxLevMinSUL corresponding to a specific NR frequency, the terminal proceeds to operation 2h-30.

[0157] If the terminal supports the SUL function and provides a value of q-RxLevMinSUL corresponding to a specific NR frequency, then in operation 2h-25, during intra-frequency / inter-frequency cell reselection to the specific frequency supporting SUL, the terminal applies the received value of q-RxLevMinSUL as Q of Srxlev rxlevmin The value of .

[0158] If the terminal does not support the SUL function or does not provide the value of q-RxLevMinSUL corresponding to the specific NR frequency, then in operation 2h-30, the terminal applies the received value of q-RxLevMin as the Q value of Srxlev. rxlevmin The value of .

[0159] Fig.2Iis a block diagram showing a configuration of a terminal according to an embodiment of the present disclosure.

[0160] refer to Fig.2I The terminal includes a radio frequency (RF) processor 2i-10, a baseband processor 2i-20, a storage unit 2i-30 and a controller 2i-40. The controller 2i-40 may also include a multi-connection processor 2i-42.

[0161] The RF processor 2i-10 is used to send or receive signals through a wireless channel, such as frequency band conversion and amplification of signals. That is, the RF processor 2i-10 up-converts the baseband signal provided by the baseband processor 2i-20 into an RF band signal and then sends the RF band signal through the antenna, and down-converts the RF band signal received through the antenna into a baseband signal. For example, the RF processor 2i-10 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.2I Only one antenna is shown, but the terminal may be provided with multiple antennas. In addition, the RF processor 2i-10 may include multiple RF chains. In addition, the RF processor 2i-10 may perform beamforming. For beamforming, the RF processor 2i-10 may adjust the phase and amplitude of each signal sent or received through multiple antennas or antenna elements. In addition, the RF processor 21-10 may perform MIMO and may receive multiple layers during the operation of a multiple-input and multiple-output (MIMO) operation.

[0162] The baseband processor 2i-20 performs the conversion function between the baseband signal and the bit stream according to the physical layer standard of the system. For example, when sending data, the baseband processor 2i-20 generates complex symbols by encoding and modulating the sending bit stream. In addition, when receiving data, the baseband processor 2i-20 reconstructs the received bit stream by demodulating and decoding the baseband signal provided by the RF processor 2i-10. For example, according to the OFDM scheme, when sending data, the baseband processor 21-20 generates complex symbols by encoding and modulating the sending bit stream, maps the complex symbols to subcarriers, and then performs an inverse fast Fourier transform (IFFT) operation and a cyclic prefix (CP) insertion to configure the OFDM symbol. In addition, when receiving data, the baseband processor 2i-20 divides the baseband signal provided by the RF processor 2i-10 in units of OFDM symbols, reconstructs the signal mapped to the subcarrier through a fast Fourier transform (FFT) operation, and then reconstructs the received bit stream through modulation and decoding.

[0163] The baseband processor 2i-20 and the RF processor 2i-10 send and receive signals as described above. Therefore, the baseband processor 2i-20 and the RF processor 2i-10 can be referred to as a "transmitter", "receiver", "transceiver" or "communication unit". In addition, at least one of the baseband processor 2i-20 and the RF processor 2i-10 may include multiple communication modules to support a variety of different radio access technologies. In addition, at least one of the baseband processor 2i-20 and the RF processor 2i-10 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), cellular networks (e.g., LTE), etc. Different frequency bands may include ultra-high frequency (Super High Frequency, SHF) (e.g., 2.5GHz and 5GHz) bands and millimeter wave (e.g., 60GHz) bands.

[0164] The storage unit 2i-30 stores data such as basic programs, applications, and configuration information for terminal operation. Specifically, the storage unit 2i-30 can store information related to a second access node configured to perform wireless communication by using a second radio access technology. In addition, the storage unit 2i-30 provides the stored data in response to a request from the controller 2i-40.

[0165] The controller 2i-40 controls the overall operation of the terminal. For example, the controller 2i-40 sends or receives signals through the baseband processor 2i-20 and the RF processor 2i-10. In addition, the controller 2i-40 records data into the storage unit 2i-30 and reads data from the storage unit 2i-30. To this end, the controller 2i-40 may include at least one processor. For example, the controller 21-40 may include a communication processor (CP) configured to perform communication control and an application processor (AP) configured to control a high level such as an application.

[0166] In addition, the controller 2i-40 may be configured to control: receiving system information related to cell reselection to a neighboring cell from a base station on which the terminal resides; if the terminal supports SUL and the first minimum required reception level information related to SUL is provided through the system information, obtaining a first cell selection reception level value based on the first minimum required reception level information related to SUL; and performing cell reselection to the NR cell based on the first cell selection reception level value. In addition, the controller 2i-40 may be configured to control: if the terminal does not support SUL, obtaining a second cell selection reception level value based on the second minimum required reception level information of the system information; and performing cell reselection based on the second cell selection reception level value. If the base station is an LTE base station, the system information may be related to inter-RAT cell reselection, and the first minimum required reception level information related to SUL may be used for inter-RAT cell reselection to the NR cell. If the base station is an NR base station and the neighboring cell is related to intra-frequency cell reselection, the system information including the first minimum required reception level information related to SUL may correspond to a system information block (SIB) 2 (SIB 2). If the base station is a NR base station and the neighboring cell is related to inter-frequency cell reselection, the system information including the first minimum required reception level information related to SUL may correspond to SIB 4. The system information may include the minimum required reception level information of each neighboring cell supporting SUL.

[0167] Figure 2J is a block diagram showing a configuration of a base station according to an embodiment of the present disclosure.

[0168] refer to Figure 2J The base station includes an RF processor 2j-10, a baseband processor 2j-20, a backhaul communication unit 2j-30, a storage unit 2j-40 ​​and a controller 2j-50. The controller 2j-50 may also include a multi-connection processor 2j-52.

[0169] The RF processor 2j-10 is used to send or receive signals through a wireless channel, such as frequency band conversion and amplification of signals. That is, the RF processor 2j-10 up-converts the baseband signal provided by the baseband processor 2j-20 into an RF band signal and then sends the RF band signal through the antenna, and down-converts the RF band signal received through the antenna into a baseband signal. For example, the RF processor 2j-10 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, an ADC, a DAC, etc. Figure 2J Only one antenna is shown, but the first access node can be provided with multiple antennas. In addition, the RF processor 2j-10 can include multiple RF chains. In addition, the RF processor 2j-10 can perform beamforming. For beamforming, the RF processor 2j-10 can adjust the phase and amplitude of each signal sent or received through multiple antennas or antenna elements. The RF processor 2j-10 can be configured to send one or more layers of downlink MIMO operation.

[0170] The baseband processor 2j-20 performs a conversion function between a baseband signal and a bit stream according to the physical layer standard of the first radio access technology. For example, when sending data, the baseband processor 2j-20 generates complex symbols by encoding and modulating the sending bit stream. In addition, when receiving data, the baseband processor 2j-20 reconstructs the received bit stream by demodulating and decoding the baseband signal provided by the RF processor 2j-10. For example, according to the OFDM scheme, when sending data, the baseband processor 2j-20 generates complex symbols by encoding and modulating the sending bit stream, maps the complex symbols to subcarriers, and then performs IFFT operations and CP insertion to configure OFDM symbols. In addition, when receiving data, the baseband processor 2j-20 divides the baseband signal provided by the RF processor 2j-10 in units of OFDM symbols, reconstructs the signal mapped to the subcarrier through a fast Fourier transform (FFT) operation, and then reconstructs the received bit stream through modulation and decoding. The baseband processor 2j-20 and the RF processor 2j-10 send and receive signals as described above. Therefore, the baseband processor 2j-20 and the RF processor 2j-10 can be referred to as a "transmitter", "receiver", "transceiver", "communication unit" or "wireless communication unit".

[0171] The backhaul communication unit 2j-30 provides an interface for communicating with other nodes in the network. That is, the backhaul communication unit 2j-30 converts a bit stream to be sent from the main base station to another node (e.g., the secondary base station and the core network) into a physical signal, and converts a physical signal received from another node into a bit stream.

[0172] The storage unit 2j-40 ​​stores data such as basic programs, applications, and configuration information for the operation of the main base station. Specifically, the storage unit 2j-40 ​​can store information about the bearer assigned to the accessed terminal, the measurement results reported by the accessed terminal, etc. In addition, the storage unit 2j-40 ​​can store information that becomes a standard for determining whether to provide or stop providing multiple connections to the terminal. In addition, the storage unit 2j-40 ​​provides the stored data according to the request of the controller 2j-50.

[0173] The controller 2j-50 controls the overall operation of the master base station. For example, the controller 2j-50 sends or receives a signal through the baseband processor 2j-20 and the RF processor 2j-10, or through the backhaul communication unit 2j-30. In addition, the controller 2j-50 records data in the storage unit 2j-40 ​​and reads data from the storage unit 2j-40. To this end, the controller 2j-50 may include at least one processor.

[0174] The controller 2j-50 may be configured to control: identifying a neighboring NR cell supporting SUL; generating system information related to cell reselection to a neighboring NR cell supporting SUL; and sending system information. If the terminal that has received the system information supports SUL, a first cell selection reception level value of the first minimum required reception level information related to SUL included in the system information may be obtained, and cell reselection may be performed based on the first cell selection reception level value. If the terminal does not support SUL, a second cell selection reception level value may be obtained based on the second minimum required reception level information of the system information, and cell reselection may be performed based on the second cell selection reception level value. If the base station is an LTE base station, the system information may be related to inter-RAT cell reselection, and the first minimum required reception level information related to SUL may be used for inter-RAT cell reselection to an NR cell. If the base station is an NR base station and the neighboring cell is related to intra-frequency cell reselection, the system information including the first minimum required reception level information related to SUL may correspond to SIB 2. If the base station is an NR base station and the neighboring cell is related to inter-frequency cell reselection, the system information including the first minimum required reception level information related to SUL may correspond to SIB 4. The system information may include the minimum required reception level information of each neighboring cell supporting SUL.

[0175] The embodiments shown and described in the specification and the drawings are only for the purpose of easily describing the contents of the present disclosure and helping to understand the present disclosure, and are not intended to limit the scope of the present disclosure. Therefore, it should be understood that, in addition to the embodiments disclosed herein, all modifications and changes or forms of modifications and changes based on the technical concept of the present disclosure fall within the scope of the present disclosure.

[0176] While the present disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents.

Claims

1. A method performed by a terminal in a communication system, the method include: Sending a request message for system information related to cell reselection of a new radio interface NR neighboring cell to the base station; receiving, from a base station, system information related to cell reselection of an NR neighboring cell, the system information comprising first minimum required reception level information for each NR frequency, wherein in the case where the NR neighboring cell supports a supplementary uplink (SUL), the system information further comprises second minimum required reception level information for the SUL; In a case where the terminal supports SUL and in a case where the system information includes second minimum required reception level information of the SUL of the NR neighboring cell, performing cell reselection using a first cell selection reception level value acquired based on the second minimum required reception level information of the SUL; as well as When the terminal does not support SUL or when the system information does not include the second minimum required reception level information of the SUL of the NR neighboring cell, the cell reselection is performed using the second cell selection reception level value obtained based on the first minimum required reception level information.

2. The method according to claim 1, in, In case the base station corresponds to a Long Term Evolution (LTE) base station, the system information relates to inter-radio access technology (RAT) cell reselection, and Among them, the second minimum required reception level information related to SUL is used for inter-RAT cell reselection to NR cell.

3. The method according to claim 1, in: In the case where the base station corresponds to an NR base station and the NR neighbor cell is related to intra-frequency cell reselection, the system information corresponds to system information block 2 SIB 2; and In the case where the base station corresponds to a NR base station and the NR neighbor cell is related to inter-frequency cell reselection, the system information corresponds to SIB 4.

4. A terminal in a communication system, the terminal include: Transceiver; and The controller is configured as: Sending a request message for system information related to cell reselection of a new radio interface NR neighboring cell to a base station via a transceiver, receiving, via a transceiver, system information related to cell reselection of an NR neighboring cell from a base station, the system information comprising first minimum required reception level information for each NR frequency, wherein in a case where the NR neighboring cell supports a supplementary uplink (SUL), the system information further comprises second minimum required reception level information for the SUL, In a case where the terminal supports SUL and in a case where the system information includes second minimum required reception level information of the SUL of the NR neighboring cell, performing cell reselection using the first cell selection reception level value acquired based on the second minimum required reception level information of the SUL, and When the terminal does not support SUL or when the system information does not include the second minimum required reception level information of the SUL of the NR neighboring cell, the cell reselection is performed using the second cell selection reception level value obtained based on the first minimum required reception level information.

5. The terminal according to claim 4, in, In case the base station corresponds to a Long Term Evolution (LTE) base station, the system information relates to inter-radio access technology (RAT) cell reselection, and Among them, the second minimum required reception level information related to SUL is used for inter-RAT cell reselection to NR cell.

6. The terminal according to claim 4, in: In the case where the base station corresponds to an NR base station and the NR neighbor cell is related to intra-frequency cell reselection, the system information corresponds to system information block 2 SIB 2; and In the case where the base station corresponds to a NR base station and the NR neighbor cell is related to inter-frequency cell reselection, the system information corresponds to SIB 4.

7. A method performed by a base station in a communication system, the method include: receiving, from a terminal, a request message for system information related to cell reselection of a neighboring cell of a new radio interface NR; generating system information related to cell reselection to an NR neighbor cell, the system information comprising first minimum required reception level information for each NR frequency, wherein in the case where the NR neighbor cell supports a supplementary uplink (SUL), the system information further comprises second minimum required reception level information for the SUL; and Sending system information related to cell reselection of NR neighboring cells, Wherein, when the system information includes the second minimum required reception level information of the SUL of the NR neighboring cell, the second minimum required reception level information of the SUL enables the terminal supporting the SUL to obtain the first cell selection reception level value based on the second minimum required reception level information, Among them, when the system information does not include the second minimum required reception level information of the SUL of the NR neighboring cell or when the terminal does not support SUL, the first minimum required reception level information enables the terminal to obtain the second cell selection reception level value based on the first minimum required reception level information.

8. The method according to claim 7, in, In case the base station corresponds to a Long Term Evolution (LTE) base station, the system information relates to inter-radio access technology (RAT) cell reselection, and Among them, the second minimum required reception level information related to SUL is used for inter-RAT cell reselection to NR cell.

9. The method according to claim 7, in: In the case where the base station corresponds to an NR base station and the NR neighbor cell is related to intra-frequency cell reselection, the system information corresponds to system information block 2 SIB 2; and In the case where the base station corresponds to a NR base station and the NR neighbor cell is related to inter-frequency cell reselection, the system information corresponds to SIB 4.

10. A base station in a communication system, the base station include: Transceiver; and controller, and is configured as: Receiving, via the transceiver, from the terminal a request message for system information related to cell reselection of a new radio interface NR neighboring cell; generating system information related to cell reselection to an NR neighbor cell, the system information comprising first minimum required reception level information for each NR frequency, wherein in the case where the NR neighbor cell supports a supplementary uplink (SUL), the system information further comprises second minimum required reception level information for the SUL; and Sending system information related to cell reselection of NR neighboring cells via the transceiver, Wherein, when the system information includes the second minimum required reception level information of the SUL of the NR neighboring cell, the second minimum required reception level information of the SUL enables the terminal supporting the SUL to obtain the first cell selection reception level value based on the second minimum required reception level information, Among them, when the system information does not include the second minimum required reception level information of the SUL of the NR neighboring cell or when the terminal does not support SUL, the first minimum required reception level information enables the terminal to obtain the second cell selection reception level value based on the first minimum required reception level information.

11. The base station according to claim 10, in, In case the base station corresponds to a Long Term Evolution (LTE) base station, the system information relates to inter-radio access technology (RAT) cell reselection, and Among them, the second minimum required reception level information related to SUL is used for inter-RAT cell reselection to NR cell.

12. The base station according to claim 10, in, In case the base station corresponds to an NR base station and the NR neighbour cell is related to intra-frequency cell reselection, the system information corresponds to system information block 2 SIB 2, and Among them, when the base station corresponds to the NR base station and the NR neighbor cell is related to the inter-frequency cell reselection, the system information corresponds to SIB 4.

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